Great Grey Shrike
Encyclopedia
The Great Grey Shrike or Northern Grey Shrike (Lanius excubitor) is a large songbird
species
in the shrike
family
(Laniidae). It forms a superspecies
with its parapatric southern relatives, the Southern Grey Shrike
(L. meridionalis), the Chinese Grey Shrike
(L. sphenocerus) and the Loggerhead Shrike
(L. ludovicianus). Within the Great Grey Shrike species itself, there are nine subspecies. Males and females are similar in plumage, pearly grey above with a black eye-mask and white underparts.
Breeding takes place generally north of 50° northern latitude in northern Europe and Asia, and in North America (where it known as the Northern Shrike) north of 55° northern latitude in Canada and Alaska
. Most populations migrate
south in winter to temperate
regions. The Great Grey Shrike is carnivorous, with rodent
s making up over half its diet.
established the quasi-scientific term lanius for the shrikes. Linnaeus chose his specific name because the species "observes approaching hawk
s and announces [the presence] of songbirds" as he put it. This habit was also put to use in falconry
, as fancifully recorded by William Yarrell
later.
The species was first scientifically described by Carl Linnaeus in his 1758 edition of Systema Naturae
under the current scientific name. His description is L[anius] cauda cuneiformi lateribus alba, dorso cano, alis nigris macula alba – "a shrike with a wedge-shaped white-bordered tail, back grey, wings black with white spot". At that time, none of the other grey shrikes – including the Lesser Grey Shrike
(L. minor), for which the description of the tail pattern is incorrect and which some authors already recognized as distinct – were considered separate species by Linnaeus, but that was to change soon. Linnaeus' binomial name replaced the cumbersome and confusing descriptive names of the earlier naturalist
books he gives as his sources: in his own Fauna Svecica he named it ampelis caerulescens, alis caudaque nigricantibus ("light-blue waxwing
, wings and tail blackish"), while it is called pica cinerea sive lanius major ("ash-grey magpie
or greater shrike") by Johann Leonhard Frisch, who in his splendid colour plate confused male and female. But most authors cited by Linnaeus – Eleazar Albin
, Ulisse Aldrovandi
, John Ray
and Francis Willughby
– called it lanius cinereus major or similar, which is a near-literal equivalent of the common name "Great Grey Shrike". The type locality of Linnaeus is simply given as Europa ("Europe").
, Conrad Gessner
, John Ray
and Francis Willughby
also reported old folk names
, mainly from Germanic languages
: Wereangel or Wierangel from the Pennines
of England (where it was noted as a vagrant) as well as Warkangel, Werkengel or Wurchangel in various German dialects (e.g. around Frankfurt/Main and Strasbourg
) probably mean "choking angel
" (cf. Standard German
Würgeengel). These names are unlikely to significantly pre-date the times of Saint Boniface
(c.700 AD) because of their Christian
connotation; the related Werkenvogel ("choking bird") might, however, do so. The English version, having become Wariangle or Weirangle, was eventually transferred to the native Red-backed Shrike
(L. collurio) and lingered on into modern times in Yorkshire
. Along the Upper Rhine
between Strasbourg and Heidelberg
for example, Linkenom is attested; its origin is unclear. Low German
Neghen-doer and Middle German
Nünmörder were also used; this has today evolved into Neuntöter and specifically means the Red-backed Shrike, but could in earlier times refer to any native Lanius
. It literally means "killer of nine [prey animals]" and refers to the food caches. A falconer
's name for the Great Grey Shrike was Mattages(s)(e), which is related to Mat'agasse from the western Alps
. These terms may mean "magpie
killer", due to their use for luring carnivorous birds to hunters – but perhaps more likely "killer magpie", considering that the bird was believed to be a peculiar sort of magpie by Johann Leonhard Frisch and others, and that another vernacular English name was "murdering pie". "Shrike", meanwhile, is of Germanic origin also and dates back at least to Middle
or Early Modern English
schricum. This is related to such words as Norwegian and Swedish skrika ("shriek, skrike"), German Schrei ("scream") or Icelandic shrikja ("shrieker"). But it seems to have become the dominant term only in rather recent times, for as late as the 18th century, the species was still widely known as "greater butcher-bird" in English, just like it was known as the boucher ("butcher") in the French Jura. A whimsical name – presumably from Scotland
or nearby England – was "white wisky
John" in reference to its wavy and somewhat unelegant flight, during which its large areas of light plumage
are conspicuous.
(Laniidae) is a member of the Corvoidea, the most ancient of the four large songbird superfamilies. Among its superfamily, the closest relatives of the Laniidae are probably the Corvidae
(crows and allies). Little reliable data exists on its evolution
; certainly (even though the supposed ancestral shrike "Lanius" miocaenus might not belong in the Laniidae, and probably does not belong in the same genus as L. excubitor) the genus dates back to Miocene
times. A Lanius fossil
from the Late Miocene
Turolian
age, c.6 Ma (million years ago), has been found at Polgárdi
(Hungary). Its relationship to the modern species is unclear. However, all things considered, the grey shrike lineage probably represents the Holarctic
sister to the African radiation of fiscal shrikes. These two seem to have originated in a west- or southwestward expansion from the genus' origin, which (considering the biogeography
of living Lanius lineages) was probably somewhere between Asia Minor
and Central Asia. At the time of the Polgárdi fossil, it is rather likely that the grey shrikes were a distinct lineage already; given that they and the fiscals generally follow Bergmann's Rule
, the smallish fossil makes an unlikely ancestor to the large grey shrikes even when taking into account the somewhat warmer Miocene climate
.
The grey shrike superspecies
consists of L. excubitor and its parapatric southern relatives. As mentioned above, the other members of this group are the Southern Grey Shrike
(L. meridionalis), the Chinese Grey Shrike
(L. sphenocerus) and the Loggerhead Shrike
(L. ludovicianus). The center of this group's radiation is probably in the eastern Mediterranean region, and the Southern Grey Shrike represents the basalmost form. The other three only diverged during the expansion into temperate regions. This must have happened fairly recently, because lineage sorting is not complete in the grey shrikes, and most of the present-day habitat
of L. excubitor was uninhabitable during much of the Quaternary glaciation
. Because of the phylogenetic uncertainties surrounding this close-knit group in the absence of a good fossil record, some refrain from splitting them up into distinct species; most modern authors do so however.
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Within the Great Grey Shrike, 9 subspecies
can be recognized. They can be divided into three groups, occurring in western Eurasia, eastern Eurasia and North America, respectively:
W Eurasian group
E Eurasian group
North American group
—and weighs around 60 to 70 g (2.1 to 2.5 oz), although some subspecies
are noticeably smaller or larger, and even in the nominate subspecies adult weights between 48 and 81 g (1.7 to 3 oz) are recorded. The wings are around 11.4 cm (4.5 in) and the tail around 10.9 cm (4.3 in) long in the nominate subspecies, its bill measures about 23 mm (0.9 in) from tip to skull, and the tarsometatarsus
part of its "legs" (actually feet) is around 27.4 mm (1.1 in) long.
The general colour of the upperparts is pearl grey, tinged brownish towards the east of its Eurasian range. The cheeks and chin as well as a thin and often hard-to-see stripe above the eye are white, and a deep black mask extends from the beak
through the eye to the ear coverts; the area immediately above the beak is grey. The scapulars (shoulder feathers) are white, and the wings are black with a white bar made up by the bases of the primary remiges, continuing slightly offset onto the bases of the secondary remiges in some regions. The tail is black, long, and pointed at the tip; the outer rectrices have white outer vane
s. The underparts are white, slightly tinged with grey in most subspecies
. In particular the breast is usually darker and sometimes browner than the rest of the light underside, and may appear as an indistinct band between the lighter belly and white throat. In the subspecies around the North Pacific in particular and in females elsewhere too, there may be faint brownish bars on the breast. The bill is large and hooked at the tip and coloured nearly black, but pale at the base of the under mandible
(though the extent varies season
ally). The legs and feet are blackish.
Males and females are about the same size, and do not differ conspicuously in appearance except by direct comparison. In the female the underparts are greyer and are usually visibly barred greyish-brown, and the white wing and tail markings are characteristically less in extent (though this is rarely clearly visible except in flight). Fledge
d young birds are heavily tinged greyish-brown all over, with barring on the upperside and indistinct buff
y-white markings. The tips of the tertiary remiges and the wing coverts are also buffy, with a black band in the latter. In the North American subspecies borealis, the fledglings are tinged quite brown indeed on upperside and wings, and have sharp and dark underside bars. In Eurasia, fledglings moult
into a female-like plumage with the tertiary bars usually remaining in autumn. Across its range, the young acquire the adult plumage in their first spring.
consists of short pleasant warbling strophes, interspersed with fluid whistles. The individual phrases may go like tu-tu-krr-pree-pree or trr-turit trr-turit.... To announce that it has become aware of someone straying into its territory – be it a female or male of its species or a large mammal
– it gives long shrill raspy whistles like trrii(u) or (t')kwiiet. To announce to females, it often mixes these whistles with a strophe of song. A softer whistle goes like trüü(t). These whistles are also used in duets between mates in winter and neighbors in the breeding season. Various contact calls have been described as chlie(p), gihrrr, kwä or wuut. These are frequently heard during courtship, interspersed with song phrases as the harsh whistles are in pre-courtship. The song becomes softer and more warbling as the male shows the female around his territory, and at potential nest sites the male gives a lively chatter containing fluting tli-tli, prrr trills and kwiw...püh calls.
When disturbed its alarm note is a harsh jay
-like k(w)eee, greee or jaaa, often repeated twice. The more excited the birds become, the higher and faster the calls get, via chek-chek-chek to a rattle trr-trr-trr or an explosive aak-aak-aak. Bird of prey
alert is given with a whistle breezeek. Knuk calls are given with adults confronted with a potential threat to their young. To beg for food – young to adults or pairmembers to each other –, rows of waik calls are given. This species sometimes tries to attract small songbirds by mimicking
their calls, so it may attempt to catch them for food.
The Southern Grey Shrike
(L. meridionalis) was formerly included in the Great Grey Shrike as subspecies
. It occurs in SW Europe (Iberian Peninsula
and France) southwards to Africa around the Sahara
, and also in Central Asia. It prefers different habitat
– lightly wooded grassland in the Great, more arid
shrubland
in the Southern Grey Shrike – and where the species' ranges overlap, they do not hybridize at present (though they may have done so in past millennia).
Elsewhere, the southern parapatric relatives of the L. excubitor are the Chinese Grey Shrike
(L. sphenocerus) from East Asia
and the Loggerhead Shrike
(L. ludovicianus) from North America. The Northern Grey Shrike is sympatric in winter quarters with each of its three close relatives at the north of their range. Their overall coloration is – apparently plesiomorphically – shared in sub-Saharan Africa
by the somewhat more distantly related Grey-backed Fiscal
(L. excubitoroides) which is found from the Sahel
eastwards, and Mackinnon's Fiscal (L. mackinnoni) of the Congo Basin
region. The Lesser Grey Shrike
(L. minor, Balkans
to Central Asia) seems to be quite distinct indeed and is sympatric with the Grey Shrike superspecies
between Eastern Europe and Central Asia; it may be more closely related to the small brown shrikes and resemble the bold, aggressive and hard-to-catch grey shrikes because of Batesian mimicry
.
The Southern Grey Shrike is clearer and usually darker grey above, and not tinged grey but often decidedly pinkish on the belly and particular breast; the white "eyebrow" extends to over the beak, which has typically a larger pale base. The barring pattern is less developed at all ages, hardly ever present even in females, and slighter in the otherwise very similar fledgling
s.
East Asian L. excubitor are barely sympatric with the Chinese Grey Shrike. The latter is larger and generally differs from the Northern species as the Southern does, and in addition has much larger white areas in wings and tail.
The Loggerhead Shrike is hard to distinguish, but the proportion of the head to the beak (which seems stubby in L. ludovicianus by comparison and is all-dark) is usually reliable. Indeed, the term "loggerhead
" refers to the relatively larger head of the southern species.
The Lesser Grey Shrike is a smaller and comparatively short-tailed bird. It can best recognized by its rather large black area above the bill, almost reaching to the forehead and without a white stripe above it. In flight, the wide instead of pointed black tail end of L. minor is characteristic. The African species are completely allopatric with L. excubitor; they lack white scapulars (Grey-backed Fiscal) or wingspots (Mackinnon's Fiscal) and differ in some other details, particularly the tail pattern.
regions of the Northern Hemisphere. Generally, its breeding range is limited to areas north of 50° northern latitude in Eurasia, and north of 55° northern latitude in North America. In the high mountains of the Altai-Tian Shan
region, it ranges south perhaps as far as 42° northern latitude. Its northern limit is generally 70° northern latitude, except in eastern Canada (Quebec
) where it only reaches up to about 60° northern latitude. It is only found as a vagrant in Iceland
, the British Isles
, the Mediterranean region (excluding the Iberian Peninsula
and perhaps Romania
but including Cyprus
), and Korea
. There do not appear to be breeding records from the entire Kamchatka Peninsula
; in Switzerland, Czechia and southern Germany small populations were found in the mid-20th century but have declined or even disappeared since then.
Except for the subspecies
bianchii which is largely all-year resident, and subspecies excubitor in the temperate European parts of its range with their mild maritime climate, the species is a short-distance migrant
. The migrations are triggered by scarcity of food and therefore, according to prey population levels, the winter range might little extend south beyond the breeding range, or be entirely parapatric to it. The populations of the Central Asian mountains mostly migrate downslope rather than southwards. Females are more prone to migration than males; they do not appear to migrate, on average, longer or shorter distances than males, and consequently are the dominant sex in many parts of the winter range. Birds leave for winter quarters a more or less short time after breeding – July to October, with most birds staying to September – and return to nest mainly in March/April, but some only arrive in May. In recent decades, the number of birds remaining on the breeding grounds all year has been noted to increase e.g. in Fennoscandia
, whereas for example borealis seems to be as rare a winter visitor in northern Ohio
as it was a century ago.
The preferred habitat
is generally open grassland
, perhaps with shrub
s interspersed, and adjacent lookout points. These are normally trees – at forest edges in much of the habitat, but single trees or small stands at the taiga
-tundra
border. In steppe
, it will utilize any isolated perch, be it fence posts, power line
s or rocks. In general, some 5–15 perching sites per hectar habitat seem to be required. It avoids low grassland with no lookouts and nesting opportunities (trees or large shrubs), as well as dense forest with no hunting ground. Apart from grassland, the birds will utilize a variety of hunting habitats, including bog
s, clearing
s or non-industrially farmed fields
. Breeding birds appear to have different microhabitat desires, but little detail is known yet.
s" hold territories more ephemeral
ly. This leads to shifts in population density
between regions, as "floaters" move between groups of territorial birds in search of a bountiful unclaimed territory to settle down and/or a partner to mate with. On the wintering grounds, pairs separate to account for the lower amount of food available at that time, but if both members migrate they tend to have their wintering grounds not far apart. As it seems, once an individual Great Grey Shrike has found a wintering territory it likes, it will return there subsequently and perhaps even try to defend it against competitors just like a summer territory. Throughout the year, the birds regularly but briefly move through a range up to three times larger than their territory; this is tolerated by territory owners in winter more easily than in summer, and the parts of Europe where all-year residents and winter visitors co-occur typically have population densities around 8 birds/km2 (about 30 per square mile) and occasionally more in winter.
Before and after the nesting season, groups of breeding birds will sometimes initiate gatherings; these seem to occur at the boundary of the group's combined range or in the unclaimed land separating it from neighboring groups. The initiation signal is a conspicuous display flight given by a bird surveying its territory: it spirals tens of meters/yards high into the air, usually briefly does a fluttering hover at the top of the spiral, and then glides down. Group neighbors will respond by performing the same type of flight, and eventually about half the group's members will depart to the meeting location where they will spend several tens of minutes – sometimes more than one hour – chattering, calling, duetting, and excitedly moving about the meeting site (which typically is some small tree or shrubbery). In winter, birds will often assemble in small groups and roost together, particularly to keep warm during the night; this is apparently not initiated with a specific assembly display however.
The flight of the Great Grey Shrike is undulating and rather heavy, but its dash is straight and determined. It is, as noted above, also capable of hover
flights, which last briefly but may be repeated time after time because of the birds' considerable stamina. It will usually stay low above the ground in flight, approaching perches from below and landing in an upward swoop. In social interactions, birds signal an aggressive stance by a bold upright posture, fanning and then flicking the tail and eventually the wings also as the bird gets more excited. It signals its readiness to strike at an intruder by shifting to a horizontal
pose and fluffing its feathers, raising them into a small crest along the top of the head. Birds appease conspecifics by head-turns away from them (if close by), or by imitating the crouching fluttering pose and calls given by fledgling
s begging for food (if sitting father apart). The submission
gesture to prevent an imminent attack by a conspecific is pointing the beak
straight up.
North American fledgling
s apparently have one moult
in their first spring only, in which they acquire adult plumage. Eurasian ones moult part of their juvenile plumage before their first winter, and the rest in spring. Adults moult on their breeding grounds before going on migration, or before the depth of winter if they are resident. Sometimes adults also seem to moult some feathers before attempting to breed. As moult requires a considerable investment of energy, some significant evolution
ary benefits to offset this are likely. Reducing feather wear and parasite load, moulting can make a bird more physically attractive and healthy, and may thus increase its chance of successful reproduction. The phenomenon is not well understood, however.
The Great Grey Shrike eats small vertebrate
s and large invertebrate
s. To hunt, this bird perches on the topmost branch of a tree, telegraph pole or similar elevated spot in a characteristic upright stance some meters/yards (at least one and up to 18 m/20 yd) above ground. Alternatively, it may scan the grassland below from flight, essentially staying in one place during prolonged bouts of mainly hovering flight that may last up to 20 minutes. The keen eye of the watchful "sentinel" misses nothing that moves. It will drop down in a light glide for terrestrial
prey or swoop hawk
-like on a flying insect
. Small birds are sometimes caught in flight too, usually by approaching them from below and behind and seizing their feet with the beak. If no prey ventures out in the open, Great Grey Shrikes will rummage through the undergrowth or sit near to hiding places and flash their white wing and tail markings to scare small animals into coming out. As noted above, it will sometimes mimic
songbirds to entice them to come within striking distance.
Typically, at least half the prey biomass
is made up from small rodent
s from the Cricetidae
(vole
s, American mice
and sometimes lemming
s) and Murinae
(Eurasian mice and sometimes young Eurasian rat
s). Shrew
s, songbird, lizard
s, and frog
s and toad
s (typically as tadpole
s) make up most of the remaining vertebrate prey. Birds are generally of little importance however, except in spring when male songbirds are engaged in courtship display
and often rather oblivious of their surroundings, in late summer when inexperienced fledgling
s abound, and in winter when most small mammals hibernate. Occasionally bat
s, newt
s and salamander
s, and even fish
are eaten. Prey animals may exceptionally be almost as large as the birds themselves, for example chicks of the Willow Grouse
(Lagopus lagopus) or a young Ermine
(Mustela nivalis). Large arthropod
s are the secondmost important prey by quantity, though not by biomass; in the latter respect they are only a bit more important than birds, except as food for nestlings where they usually form a substantial part of the diet. Most important among invertebrate prey are insect
s, especially beetle
s (Coleoptera), cricket
s and grasshoppers
(Orthoptera
), and bumblebee
s and wasp
s (Hymenoptera
). Invertebrate prey of minor importance are spider
s and scorpion
s (Arachnida), crayfish
and isopods (Crustacea), snail
s, and oligochaete worms. Carrion
and berries are rarely if ever eaten; though it might occasionally plunder songbird nests this is not well documented and it is not known to eat egg
s.
Prey is killed by hitting it with the hooked beak, aiming for the skull in vertebrates. If too large to swallow in one or a few chunks, it is transported to a feeding site by carrying it in the beak or (if too large) in the feet. The feet are not suited for tearing up prey, however. It is rather impaled upon a sharp point – thorn
s or the barbs of barbed wire
– or wedged firmly between forking branch
es. Thus secured, the food can be ripped into bite-sized pieces with the beak. Orthoptera that the birds have recognized as containing noxious chemicals are left impaled in the larder for several days, until the chemicals that usually deter predators have been degraded. Great Grey Shrikes have also been observed to impale Common Toad
s (Bufo bufo) and skin
them – by ripping open the back skin and pulling it over the head – to avoid contamination of the meat by the toxic skin secretions. Large bones and similar inedible parts of prey animals are usually not ingested, but smaller ones such as tiny bones or the elytra of beetles are eaten and later regurgitate
d as pellet
s.
The basic metabolic rate of the Great Grey Shrike is around 800 milliwatts, or somewhat more than 11 milliwatts per gram of body mass. An adult of this species needs about 50 g (1.8 oz) of prey a day, probably somewhat more in winter. Under most circumstances, this would thus translate to one or two rodent
s, one or two additional vertebrate prey animals (including rodents), and up to a single vertebrate prey item's worth of invertebrates. Surplus food may be impaled for storage. These "larder
s" are typically around 1 meter above ground and can be found anywhere within the birds' territory, but tend to be rather in the general vicinity of nest sites than far away from them.
is destroyed before hatching they are usually able to produce a second one. Their monogamous pair bond
is strong during the breeding season and loosens over winter; birds often choose a different mate than the year before. To seek out potential mates, males will venture outside their breeding territories. If a female thus encountered finds a male to her liking, she will visit to see whether they get along well and inspect the nesting sites he can offer. The courtship period is generally longer than in the Southern Grey Shrike
(L. meridionalis), usually starting about March and lasting to April/May. At first, the female rebuffs the male, only allowing him to feed her. Males give increasingly vocal displays and show off the white markings of the wings in flight and of the tail by fanning it and turning away from the female. He also occasionally turns to sit at a right angle to her. Eventually, the female will join in the male's displays, and the songs will become duets. To feed females and to show off their hunting prowess, males will make their food caches in conspicuous places during this time. When presenting nesting sites, males give the variety of calls described above and jerk their head and fanned tail.
Copulation is typically initiated by the male bringing an attractive prey item to the female. With both giving begging calls, they approach until they are side by side. The male then raises and swings his body left and right a few times, and passes the prey to the female, followed by the actual copulation. The gatherings of neighbor groups (see above) cease when nesting is underway, and when the eggs are nearly ready to lay, the male guards his partner closely, perching higher than her to watch for threats and frequently feeding her. This apparently ensures her physical well-being rather than preventing extra-pair copulations, as neighboring males will stray through each other's territory to snatch a quick fling with the resident females. In this, they have almost a one-in-three chance of success, and consequently the average Grey Shrike nest is very likely to contain offspring of more than one male. Females may deposit their eggs in neighbors' nests, but this seems to occur more rarely; in general, mated females are fairly reclusive after their eggs have started developing. A full clutch
of eggs can be produced by a female in about 10–15 days.
Nest
s are built in April or May more than 1 meter (1 yard) above ground in trees. This height varies according to habitat, but while nests have been found almost 40 m (44 yards) up, most are 2–16 m above ground. Presence of mistletoe
s or vine
s like Common Ivy (Hedera helix) on side branches near the trunk (where nests are preferentially built) will make a tree markedly more attractive. Fieldfare
s (Turdus pilaris) nesting in the vicinity will also increase the desirability of nest sites to Great Grey Shrikes, which moreover often refuse to prey upon these thrush
es' nestlings though the opportunity is there. Apparently, the two species are more efficient in spotting potential nest predators – in particular corvids – early on and mobbing them off cooperatively than either is on its own. Otherwise, there is no clear preference for particular taxa of nesting trees, provided they are sufficiently dense. Conifers seem to have become more popular with European L. excubitor in recent decades, but a diversity of deciduous trees is used just as well. Far more rarely, large and especially thorn
y shrubs are used for nesting. The actual nesting site is chosen by the male; the courtship visits of the female are mainly to form and strengthen the pair bond. Also, though the partners build the nest together, the male collects most of the nesting material. The cup nest is quite sizable, measuring 20–28 cm (8–11 in) in outer diameter. Its body is constructed of coarse vegetable material – mainly large twigs and chunks of moss
, though bits of fabric and rubbish may be added. The interior cup is 8–12 cm (3-4.7 in) in diameter and 10–15 cm (4–6 in) deep; it is lined with fine twigs and roots, lichen
, hair and feathers. Building a nest from scratch takes a pair one to two weeks, but if nests of the previous year in good locations remain usable, they are repaired rather than discarded.
Laying usually takes place in May. The clutch numbers 3–9 eggs, typically around 7, with North American clutches tending to be larger on average than European ones. If a second clutch is produced in one breeding season, it is smaller than the first one. The eggs have a white background color, usually with a grey hue and sometimes with a blue one; they are patterned with blotches of yellowish- to reddish-brown and purplish-grey, often denser around the blunt end. They measure around 26 mm (1 inch) in length and 19.5 mm (0.767716535433071 in) in width. Incubation
takes around 16 days but may be closer to three weeks for large clutches; it is generally done only by the female. While the male may briefly take over incubating, his task during this time is to provide food. The altricial
nestlings hatch naked, blind and pink-skinned, weighing c.4 g (0.141095848420448 oz); their skin turns darker after a few days. The inside of their beak is pink and they probably lack spots or other prominent marks; the wattles at the corners of the mouth are yellow as in many passerine
s. As the nestlings grow, the female broods them, and later on assists in providing food. The young fledge
after 2–3 weeks, typically in late June or early July; they become independent of their parents about 3–6 weeks later. Sometimes, a parent will single out particular fledglings (possibly the weakest ones) and focus their care and feeding on these during this time. Other adults have occasionally been recorded assisting in feeding a pair's offspring; it is not clear whether these helpers at the nest
are offspring of previous years, or unrelated non-breeding "floaters" or breeding neighbors.
Common Cuckoo
s (Cuculus canorus) have been noted as regular brood parasite
s of L. e. excubitor in the past; for reasons unknown this has ceased since the late 1970s or so. It may well be that the cuckoo's gens
laying eggs similar to those of the Great Grey Shrike has become extinct. Among predators of eggs and nestlings, corvids (Corvidae) – extremely close relatives of the shrikes (Laniidae) as it happens – are most significant.
Usually more than half of all nests manage to hatch at least one young, and around three-quarters of all eggs laid hatch, suggesting that if eggs are lost before hatching, it usually is the entire clutch. Half to three-quarters of the hatched young successfully fledge under most circumstances. They will become sexually mature in their first spring and often attempt to breed right away. On average, Great Grey Shrikes get a chance at four breeding attempts during their life, with most birds in the wild getting eaten by a large bird of prey
or carnivorous mammal
or dying of other causes before the end of their fifth winter. The maximum documented lifespan, however, is 12 years.
. Overall, its stocks seem to be declining in the European part of its range since the 1970s. In North America, the populations seem to have been stable by contrast, except in the east. The roughly 11-year sunspot cycle does not seem to be closely linked to these fluctuations, and probably neither to the eight-year cycle recorded in subspecies
borealis (and perhaps present in others). Rather, the increase and decline seem to be reactions to changing land use, with an increase as the number of agricultural workers declined after World War II and land fell fallow, declining again when land consolidation (see e.g. Flurbereinigung
) had seriously depleted the number of hedgerows and similar elevated growth formerly common amidst the agricultural landscape. For such a predatory bird, the indiscriminate use of pesticide
s (which will accumulate in adult carnivores and inhibit breeding success) around the 1960s probably had a detrimental influence on stocks too.
Altogether, the Great Grey Shrike is common and widespread and not considered a threatened species
by the IUCN (though they still include L. meridionalis in L. excubitor). Wherever it occurs, its numbers are usually many hundreds or even thousands per country. Its stronghold is the region around Sweden, where at least almost 20,000, perhaps as many as 50,000 were believed to live in the late 20th century. However, in some countries it is not robustly established; in Estonia
only a few hundred are found, with less than 200 in Belgium and some more or less than 100 in Latvia
and Lithuania
, respectively. The few dozen in the Netherlands and the 10 birds or so in Denmark might disappear because of a few years of adverse circumstances. By contrast, in Luxembourg
plentiful high-quality habitat is found; though the number of Great Grey Shrikes in this tiny country is necessarily limited, the average population density
there is 25 times as high as in Lithuania.
Songbird
A songbird is a bird belonging to the suborder Passeri of the perching birds . Another name that is sometimes seen as scientific or vernacular name is Oscines, from Latin oscen, "a songbird"...
species
Species
In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...
in the shrike
Shrike
Shrikes are passerine birds of the family Laniidae. The family is composed of thirty-one species in three genera. The family name, and that of the largest genus, Lanius, is derived from the Latin word for "butcher", and some shrikes were also known as "butcher birds" because of their feeding habits...
family
Family (biology)
In biological classification, family is* a taxonomic rank. Other well-known ranks are life, domain, kingdom, phylum, class, order, genus, and species, with family fitting between order and genus. As for the other well-known ranks, there is the option of an immediately lower rank, indicated by the...
(Laniidae). It forms a superspecies
Superspecies
A superspecies is a group of at least two more or less distinctive species with approximately parapatric distributions. Not all species complexes, whether cryptices or ring species are superspecies, and vice versa, but many are...
with its parapatric southern relatives, the Southern Grey Shrike
Southern Grey Shrike
The Southern Grey Shrike, Lanius meridionalis, is a member of the shrike family.It is closely related to the Great Grey Shrike, Lanius excubitor, with which it used to be considered conspecific; where they co-occur, they do not interbreed and are separated by choice of habitat.The race L. m....
(L. meridionalis), the Chinese Grey Shrike
Chinese Grey Shrike
The Chinese Grey Shrike is a species of bird in the Laniidae family.It is found in China, Japan, North Korea, South Korea, Mongolia, and Russia.Its natural habitat is temperate forests.-External links:*...
(L. sphenocerus) and the Loggerhead Shrike
Loggerhead Shrike
The Loggerhead Shrike is a passerine bird. It is the only member of the shrike family endemic to North America; the related Northern Shrike occurs north of its range but also in the Palearctic....
(L. ludovicianus). Within the Great Grey Shrike species itself, there are nine subspecies. Males and females are similar in plumage, pearly grey above with a black eye-mask and white underparts.
Breeding takes place generally north of 50° northern latitude in northern Europe and Asia, and in North America (where it known as the Northern Shrike) north of 55° northern latitude in Canada and Alaska
Alaska
Alaska is the largest state in the United States by area. It is situated in the northwest extremity of the North American continent, with Canada to the east, the Arctic Ocean to the north, and the Pacific Ocean to the west and south, with Russia further west across the Bering Strait...
. Most populations migrate
Bird migration
Bird migration is the regular seasonal journey undertaken by many species of birds. Bird movements include those made in response to changes in food availability, habitat or weather. Sometimes, journeys are not termed "true migration" because they are irregular or in only one direction...
south in winter to temperate
Temperate
In geography, temperate or tepid latitudes of the globe lie between the tropics and the polar circles. The changes in these regions between summer and winter are generally relatively moderate, rather than extreme hot or cold...
regions. The Great Grey Shrike is carnivorous, with rodent
Rodent
Rodentia is an order of mammals also known as rodents, characterised by two continuously growing incisors in the upper and lower jaws which must be kept short by gnawing....
s making up over half its diet.
Taxonomy and systematics
The scientific name of the Great Grey Shrike literally means "sentinel butcher": Lanius is the Latin term for a butcher, while excubitor is Latin for a watchman or sentinel. This refers to the birds' two most conspicuous behaviours – storing food animals by impaling them on thorns, and using exposed tree-tops or poles to watch the surrounding area for possible prey. Use of the former by Conrad GessnerConrad Gessner
Conrad Gessner was a Swiss naturalist and bibliographer. His five-volume Historiae animalium is considered the beginning of modern zoology, and the flowering plant genus Gesneria is named after him...
established the quasi-scientific term lanius for the shrikes. Linnaeus chose his specific name because the species "observes approaching hawk
Hawk
The term hawk can be used in several ways:* In strict usage in Australia and Africa, to mean any of the species in the subfamily Accipitrinae, which comprises the genera Accipiter, Micronisus, Melierax, Urotriorchis and Megatriorchis. The large and widespread Accipiter genus includes goshawks,...
s and announces [the presence] of songbirds" as he put it. This habit was also put to use in falconry
Falconry
Falconry is "the taking of wild quarry in its natural state and habitat by means of a trained raptor". There are two traditional terms used to describe a person involved in falconry: a falconer flies a falcon; an austringer flies a hawk or an eagle...
, as fancifully recorded by William Yarrell
William Yarrell
William Yarrell was an English bookseller and naturalist.Yarrell is best known as the author of The History of British Fishes and The History of British Birds . The latter went into several editions and was the standard reference work for a generation of British ornithologists...
later.
The species was first scientifically described by Carl Linnaeus in his 1758 edition of Systema Naturae
Systema Naturae
The book was one of the major works of the Swedish botanist, zoologist and physician Carolus Linnaeus. The first edition was published in 1735...
under the current scientific name. His description is L[anius] cauda cuneiformi lateribus alba, dorso cano, alis nigris macula alba – "a shrike with a wedge-shaped white-bordered tail, back grey, wings black with white spot". At that time, none of the other grey shrikes – including the Lesser Grey Shrike
Lesser Grey Shrike
The Lesser Grey Shrike is a member of the shrike family Laniidae.It is similar in appearance to the Great Grey Shrike Lanius excubitor and the Southern Grey Shrike L. meridionalis...
(L. minor), for which the description of the tail pattern is incorrect and which some authors already recognized as distinct – were considered separate species by Linnaeus, but that was to change soon. Linnaeus' binomial name replaced the cumbersome and confusing descriptive names of the earlier naturalist
Naturalist
Naturalist may refer to:* Practitioner of natural history* Conservationist* Advocate of naturalism * Naturalist , autobiography-See also:* The American Naturalist, periodical* Naturalism...
books he gives as his sources: in his own Fauna Svecica he named it ampelis caerulescens, alis caudaque nigricantibus ("light-blue waxwing
Waxwing
The waxwings form the genus Bombycilla of passerine birds. According to most authorities, this is the only genus placed in the family Bombycillidae.-Description:Waxwings are characterised by soft silky plumage...
, wings and tail blackish"), while it is called pica cinerea sive lanius major ("ash-grey magpie
Magpie
Magpies are passerine birds of the crow family, Corvidae.In Europe, "magpie" is often used by English speakers as a synonym for the European Magpie, as there are no other magpies in Europe outside Iberia...
or greater shrike") by Johann Leonhard Frisch, who in his splendid colour plate confused male and female. But most authors cited by Linnaeus – Eleazar Albin
Eleazar Albin
Eleazar Albin was an English naturalist and watercolourist illustrator who wrote and illustrated a number of books including A Natural History of English Insects , A Natural History of Birds and The Natural History of Spiders and other Curious Insects...
, Ulisse Aldrovandi
Ulisse Aldrovandi
Ulisse Aldrovandi was an Italian naturalist, the moving force behind Bologna's botanical garden, one of the first in Europe. Carolus Linnaeus and the comte de Buffon reckoned him the father of natural history studies...
, John Ray
John Ray
John Ray was an English naturalist, sometimes referred to as the father of English natural history. Until 1670, he wrote his name as John Wray. From then on, he used 'Ray', after "having ascertained that such had been the practice of his family before him".He published important works on botany,...
and Francis Willughby
Francis Willughby
thumbnail|200px|right|A page from the Ornithologia, showing [[Jackdaw]], [[Chough]], [[European Magpie|Magpie]] and [[Eurasian Jay|Jay]], all [[Corvidae|crows]]....
– called it lanius cinereus major or similar, which is a near-literal equivalent of the common name "Great Grey Shrike". The type locality of Linnaeus is simply given as Europa ("Europe").
Vernacular names
Ulisse AldrovandiUlisse Aldrovandi
Ulisse Aldrovandi was an Italian naturalist, the moving force behind Bologna's botanical garden, one of the first in Europe. Carolus Linnaeus and the comte de Buffon reckoned him the father of natural history studies...
, Conrad Gessner
Conrad Gessner
Conrad Gessner was a Swiss naturalist and bibliographer. His five-volume Historiae animalium is considered the beginning of modern zoology, and the flowering plant genus Gesneria is named after him...
, John Ray
John Ray
John Ray was an English naturalist, sometimes referred to as the father of English natural history. Until 1670, he wrote his name as John Wray. From then on, he used 'Ray', after "having ascertained that such had been the practice of his family before him".He published important works on botany,...
and Francis Willughby
Francis Willughby
thumbnail|200px|right|A page from the Ornithologia, showing [[Jackdaw]], [[Chough]], [[European Magpie|Magpie]] and [[Eurasian Jay|Jay]], all [[Corvidae|crows]]....
also reported old folk names
Folk taxonomy
A folk taxonomy is a vernacular naming system, and can be contrasted with scientific taxonomy. Folk biological classification is the way peoples describe and organize their natural surroundings/the world around them, typically making generous use of form taxa like "shrubs", "bugs", "ducks",...
, mainly from Germanic languages
Germanic languages
The Germanic languages constitute a sub-branch of the Indo-European language family. The common ancestor of all of the languages in this branch is called Proto-Germanic , which was spoken in approximately the mid-1st millennium BC in Iron Age northern Europe...
: Wereangel or Wierangel from the Pennines
Pennines
The Pennines are a low-rising mountain range, separating the North West of England from Yorkshire and the North East.Often described as the "backbone of England", they form a more-or-less continuous range stretching from the Peak District in Derbyshire, around the northern and eastern edges of...
of England (where it was noted as a vagrant) as well as Warkangel, Werkengel or Wurchangel in various German dialects (e.g. around Frankfurt/Main and Strasbourg
Strasbourg
Strasbourg is the capital and principal city of the Alsace region in eastern France and is the official seat of the European Parliament. Located close to the border with Germany, it is the capital of the Bas-Rhin département. The city and the region of Alsace are historically German-speaking,...
) probably mean "choking angel
Angel
Angels are mythical beings often depicted as messengers of God in the Hebrew and Christian Bibles along with the Quran. The English word angel is derived from the Greek ἄγγελος, a translation of in the Hebrew Bible ; a similar term, ملائكة , is used in the Qur'an...
" (cf. Standard German
Standard German
Standard German is the standard variety of the German language used as a written language, in formal contexts, and for communication between different dialect areas...
Würgeengel). These names are unlikely to significantly pre-date the times of Saint Boniface
Saint Boniface
Saint Boniface , the Apostle of the Germans, born Winfrid, Wynfrith, or Wynfryth in the kingdom of Wessex, probably at Crediton , was a missionary who propagated Christianity in the Frankish Empire during the 8th century. He is the patron saint of Germany and the first archbishop of Mainz...
(c.700 AD) because of their Christian
Christianity
Christianity is a monotheistic religion based on the life and teachings of Jesus as presented in canonical gospels and other New Testament writings...
connotation; the related Werkenvogel ("choking bird") might, however, do so. The English version, having become Wariangle or Weirangle, was eventually transferred to the native Red-backed Shrike
Red-backed Shrike
The Red-backed Shrike is a carnivorous passerine bird and member of the shrike family Laniidae.English common names include 'Wariangle' and 'worrier'.-Description:...
(L. collurio) and lingered on into modern times in Yorkshire
Yorkshire
Yorkshire is a historic county of northern England and the largest in the United Kingdom. Because of its great size in comparison to other English counties, functions have been increasingly undertaken over time by its subdivisions, which have also been subject to periodic reform...
. Along the Upper Rhine
Upper Rhine
The Upper Rhine is the section of the Rhine in the Upper Rhine Plain between Basel, Switzerland and Bingen, Germany. The river is marked by Rhine-kilometers 170 to 529 ....
between Strasbourg and Heidelberg
Heidelberg
-Early history:Between 600,000 and 200,000 years ago, "Heidelberg Man" died at nearby Mauer. His jaw bone was discovered in 1907; with scientific dating, his remains were determined to be the earliest evidence of human life in Europe. In the 5th century BC, a Celtic fortress of refuge and place of...
for example, Linkenom is attested; its origin is unclear. Low German
Low German
Low German or Low Saxon is an Ingvaeonic West Germanic language spoken mainly in northern Germany and the eastern part of the Netherlands...
Neghen-doer and Middle German
Middle German
In linguistics, Middle German can refer to a few variants of the German language:* Middle Low German , the northern dialects in the 11th-15th centuries...
Nünmörder were also used; this has today evolved into Neuntöter and specifically means the Red-backed Shrike, but could in earlier times refer to any native Lanius
Lanius
Lanius, the typical shrikes, are a genus of passerine birds in the shrike family. The majority of the family's species are placed in this genus. African species are known as fiscals...
. It literally means "killer of nine [prey animals]" and refers to the food caches. A falconer
Falconer
Falconer or The Falconer may refer to:*A person skilled in the art of falconry*Falconer , a family name*Falconer, New York, United StatesIn media:*Falconer , a power metal band from Sweden...
's name for the Great Grey Shrike was Mattages(s)(e), which is related to Mat'agasse from the western Alps
Alps
The Alps is one of the great mountain range systems of Europe, stretching from Austria and Slovenia in the east through Italy, Switzerland, Liechtenstein and Germany to France in the west....
. These terms may mean "magpie
Magpie
Magpies are passerine birds of the crow family, Corvidae.In Europe, "magpie" is often used by English speakers as a synonym for the European Magpie, as there are no other magpies in Europe outside Iberia...
killer", due to their use for luring carnivorous birds to hunters – but perhaps more likely "killer magpie", considering that the bird was believed to be a peculiar sort of magpie by Johann Leonhard Frisch and others, and that another vernacular English name was "murdering pie". "Shrike", meanwhile, is of Germanic origin also and dates back at least to Middle
Middle English
Middle English is the stage in the history of the English language during the High and Late Middle Ages, or roughly during the four centuries between the late 11th and the late 15th century....
or Early Modern English
Early Modern English
Early Modern English is the stage of the English language used from about the end of the Middle English period to 1650. Thus, the first edition of the King James Bible and the works of William Shakespeare both belong to the late phase of Early Modern English...
schricum. This is related to such words as Norwegian and Swedish skrika ("shriek, skrike"), German Schrei ("scream") or Icelandic shrikja ("shrieker"). But it seems to have become the dominant term only in rather recent times, for as late as the 18th century, the species was still widely known as "greater butcher-bird" in English, just like it was known as the boucher ("butcher") in the French Jura. A whimsical name – presumably from Scotland
Scotland
Scotland is a country that is part of the United Kingdom. Occupying the northern third of the island of Great Britain, it shares a border with England to the south and is bounded by the North Sea to the east, the Atlantic Ocean to the north and west, and the North Channel and Irish Sea to the...
or nearby England – was "white wisky
Whisky
Whisky or whiskey is a type of distilled alcoholic beverage made from fermented grain mash. Different grains are used for different varieties, including barley, malted barley, rye, malted rye, wheat, and corn...
John" in reference to its wavy and somewhat unelegant flight, during which its large areas of light plumage
Plumage
Plumage refers both to the layer of feathers that cover a bird and the pattern, colour, and arrangement of those feathers. The pattern and colours of plumage vary between species and subspecies and can also vary between different age classes, sexes, and season. Within species there can also be a...
are conspicuous.
Relationships and evolution
The shrike familyFamily (biology)
In biological classification, family is* a taxonomic rank. Other well-known ranks are life, domain, kingdom, phylum, class, order, genus, and species, with family fitting between order and genus. As for the other well-known ranks, there is the option of an immediately lower rank, indicated by the...
(Laniidae) is a member of the Corvoidea, the most ancient of the four large songbird superfamilies. Among its superfamily, the closest relatives of the Laniidae are probably the Corvidae
Corvidae
Corvidae is a cosmopolitan family of oscine passerine birds that contains the crows, ravens, rooks, jackdaws, jays, magpies, treepies, choughs and nutcrackers. The common English names used are corvids or the crow family , and there are over 120 species...
(crows and allies). Little reliable data exists on its evolution
Evolution
Evolution is any change across successive generations in the heritable characteristics of biological populations. Evolutionary processes give rise to diversity at every level of biological organisation, including species, individual organisms and molecules such as DNA and proteins.Life on Earth...
; certainly (even though the supposed ancestral shrike "Lanius" miocaenus might not belong in the Laniidae, and probably does not belong in the same genus as L. excubitor) the genus dates back to Miocene
Miocene
The Miocene is a geological epoch of the Neogene Period and extends from about . The Miocene was named by Sir Charles Lyell. Its name comes from the Greek words and and means "less recent" because it has 18% fewer modern sea invertebrates than the Pliocene. The Miocene follows the Oligocene...
times. A Lanius fossil
Fossil
Fossils are the preserved remains or traces of animals , plants, and other organisms from the remote past...
from the Late Miocene
Late Miocene
The Late Miocene is a sub-epoch of the Miocene Epoch made up of two stages. The Tortonian and Messinian stages comprise the Late Miocene sub-epoch....
Turolian
Turolian
The Turolian age is a period of geologic time within the Miocene used more specifically with European Land Mammal Ages. It precedes the Ruscinian age and follows the Vallesian age. The Turolian overlaps the Tortonian and Messinian ages....
age, c.6 Ma (million years ago), has been found at Polgárdi
Polgárdi
Polgárdi is a town in Fejér county, Hungary....
(Hungary). Its relationship to the modern species is unclear. However, all things considered, the grey shrike lineage probably represents the Holarctic
Holarctic
The Holarctic ecozone refers to the habitats found throughout the northern continents of the world as a whole. This region is divided into the Palearctic, consisting of Northern Africa and all of Eurasia, with the exception of Southeast Asia and the Indian subcontinent, and the Nearctic,...
sister to the African radiation of fiscal shrikes. These two seem to have originated in a west- or southwestward expansion from the genus' origin, which (considering the biogeography
Biogeography
Biogeography is the study of the distribution of species , organisms, and ecosystems in space and through geological time. Organisms and biological communities vary in a highly regular fashion along geographic gradients of latitude, elevation, isolation and habitat area...
of living Lanius lineages) was probably somewhere between Asia Minor
Asia Minor
Asia Minor is a geographical location at the westernmost protrusion of Asia, also called Anatolia, and corresponds to the western two thirds of the Asian part of Turkey...
and Central Asia. At the time of the Polgárdi fossil, it is rather likely that the grey shrikes were a distinct lineage already; given that they and the fiscals generally follow Bergmann's Rule
Bergmann's Rule
Bergmann's rule is an ecogeographic principle that states that within a broadly distributed genus, species of larger size are found in colder environments, and species of smaller size are found in warmer regions. Although originally formulated in terms of species within a genus, it has often been...
, the smallish fossil makes an unlikely ancestor to the large grey shrikes even when taking into account the somewhat warmer Miocene climate
Climate
Climate encompasses the statistics of temperature, humidity, atmospheric pressure, wind, rainfall, atmospheric particle count and other meteorological elemental measurements in a given region over long periods...
.
The grey shrike superspecies
Superspecies
A superspecies is a group of at least two more or less distinctive species with approximately parapatric distributions. Not all species complexes, whether cryptices or ring species are superspecies, and vice versa, but many are...
consists of L. excubitor and its parapatric southern relatives. As mentioned above, the other members of this group are the Southern Grey Shrike
Southern Grey Shrike
The Southern Grey Shrike, Lanius meridionalis, is a member of the shrike family.It is closely related to the Great Grey Shrike, Lanius excubitor, with which it used to be considered conspecific; where they co-occur, they do not interbreed and are separated by choice of habitat.The race L. m....
(L. meridionalis), the Chinese Grey Shrike
Chinese Grey Shrike
The Chinese Grey Shrike is a species of bird in the Laniidae family.It is found in China, Japan, North Korea, South Korea, Mongolia, and Russia.Its natural habitat is temperate forests.-External links:*...
(L. sphenocerus) and the Loggerhead Shrike
Loggerhead Shrike
The Loggerhead Shrike is a passerine bird. It is the only member of the shrike family endemic to North America; the related Northern Shrike occurs north of its range but also in the Palearctic....
(L. ludovicianus). The center of this group's radiation is probably in the eastern Mediterranean region, and the Southern Grey Shrike represents the basalmost form. The other three only diverged during the expansion into temperate regions. This must have happened fairly recently, because lineage sorting is not complete in the grey shrikes, and most of the present-day habitat
Habitat (ecology)
A habitat is an ecological or environmental area that is inhabited by a particular species of animal, plant or other type of organism...
of L. excubitor was uninhabitable during much of the Quaternary glaciation
Quaternary glaciation
Quaternary glaciation, also known as the Pleistocene glaciation, the current ice age or simply the ice age, refers to the period of the last few million years in which permanent ice sheets were established in Antarctica and perhaps Greenland, and fluctuating ice sheets have occurred elsewhere...
. Because of the phylogenetic uncertainties surrounding this close-knit group in the absence of a good fossil record, some refrain from splitting them up into distinct species; most modern authors do so however.
Subspecies
Subspecies
Subspecies in biological classification, is either a taxonomic rank subordinate to species, ora taxonomic unit in that rank . A subspecies cannot be recognized in isolation: a species will either be recognized as having no subspecies at all or two or more, never just one...
can be recognized. They can be divided into three groups, occurring in western Eurasia, eastern Eurasia and North America, respectively:
W Eurasian group
- Lanius excubitor excubitor (including melanopterus – which may be intergrades with sibiricus – and galliae) – temperate to subarcticSubarcticThe Subarctic is a region in the Northern Hemisphere immediately south of the true Arctic and covering much of Alaska, Canada, the north of Scandinavia, Siberia, and northern Mongolia...
continental EuropeContinental EuropeContinental Europe, also referred to as mainland Europe or simply the Continent, is the continent of Europe, explicitly excluding European islands....
E to W SiberiaSiberiaSiberia is an extensive region constituting almost all of Northern Asia. Comprising the central and eastern portion of the Russian Federation, it was part of the Soviet Union from its beginning, as its predecessor states, the Tsardom of Russia and the Russian Empire, conquered it during the 16th...
.
- Medium grey above, pale grey hue below. Some white on primaries and sometimes secondaries.
- Lanius excubitor homeyeri – temperate Black SeaBlack SeaThe Black Sea is bounded by Europe, Anatolia and the Caucasus and is ultimately connected to the Atlantic Ocean via the Mediterranean and the Aegean seas and various straits. The Bosphorus strait connects it to the Sea of Marmara, and the strait of the Dardanelles connects that sea to the Aegean...
coast E via Transcaucasia to W Siberia
- Lanius excubitor homeyeri – temperate Black Sea
- Lighter grey than excubitor above, dull white below. More white on primaries and secondaries.
- Lanius excubitor leucopterus – SW Russia along border to KazakhstanKazakhstanKazakhstan , officially the Republic of Kazakhstan, is a transcontinental country in Central Asia and Eastern Europe. Ranked as the ninth largest country in the world, it is also the world's largest landlocked country; its territory of is greater than Western Europe...
to SW Siberia
- Lanius excubitor leucopterus – SW Russia along border to Kazakhstan
- Light grey above, white below. Considerable white on primaries and secondaries.
E Eurasian group
- Lanius excubitor sibiricus – E Siberia to N MongoliaMongoliaMongolia is a landlocked country in East and Central Asia. It is bordered by Russia to the north and China to the south, east and west. Although Mongolia does not share a border with Kazakhstan, its western-most point is only from Kazakhstan's eastern tip. Ulan Bator, the capital and largest...
- Browner above than excubitor, distinct but delicate banding below. Some white on primary bases only.
- Lanius excubitor bianchii – SakhalinSakhalinSakhalin or Saghalien, is a large island in the North Pacific, lying between 45°50' and 54°24' N.It is part of Russia, and is Russia's largest island, and is administered as part of Sakhalin Oblast...
and possibly S Kuril IslandsKuril IslandsThe Kuril Islands , in Russia's Sakhalin Oblast region, form a volcanic archipelago that stretches approximately northeast from Hokkaidō, Japan, to Kamchatka, Russia, separating the Sea of Okhotsk from the North Pacific Ocean. There are 56 islands and many more minor rocks. It consists of Greater...
- Lanius excubitor bianchii – Sakhalin
- Smaller and paler than sibiricus, banding below pale and indistinct. Some white on primary bases only.
- Lanius excubitor mollis – Russian Altai Mountains, NW Mongolia
- Browner than sibiricus above, banding below well-developed. Little white on primary bases.
- Lanius excubitor funereus – Tian ShanTian ShanThe Tian Shan , also spelled Tien Shan, is a large mountain system located in Central Asia. The highest peak in the Tian Shan is Victory Peak , ....
and W China
- Lanius excubitor funereus – Tian Shan
- Large; quite dark and brownish, below bluish-grey with almost black banding. Little white on primary bases.
North American group
- Lanius excubitor borealis – Hudson BayHudson BayHudson Bay , sometimes called Hudson's Bay, is a large body of saltwater in northeastern Canada. It drains a very large area, about , that includes parts of Ontario, Quebec, Saskatchewan, Alberta, most of Manitoba, southeastern Nunavut, as well as parts of North Dakota, South Dakota, Minnesota,...
region of OntarioOntarioOntario is a province of Canada, located in east-central Canada. It is Canada's most populous province and second largest in total area. It is home to the nation's most populous city, Toronto, and the nation's capital, Ottawa....
and QuebecQuebecQuebec or is a province in east-central Canada. It is the only Canadian province with a predominantly French-speaking population and the only one whose sole official language is French at the provincial level....
- Similar to excubitor, but darker with faint barring below. John James AudubonJohn James AudubonJohn James Audubon was a French-American ornithologist, naturalist, and painter. He was notable for his expansive studies to document all types of American birds and for his detailed illustrations that depicted the birds in their natural habitats...
called this subspecies the Great American Shrike in his book Birds of AmericaBirds of America (book)The Birds of America is a book by naturalist and painter John James Audubon, containing illustrations of a wide variety of birds of the United States. It was first published as a series of sections between 1827 and 1838, in Edinburgh and London....
.- Lanius excubitor invictus – N AlbertaAlbertaAlberta is a province of Canada. It had an estimated population of 3.7 million in 2010 making it the most populous of Canada's three prairie provinces...
W to N AlaskaAlaskaAlaska is the largest state in the United States by area. It is situated in the northwest extremity of the North American continent, with Canada to the east, the Arctic Ocean to the north, and the Pacific Ocean to the west and south, with Russia further west across the Bering Strait...
, perhaps also Chukchi PeninsulaChukchi PeninsulaThe Chukchi Peninsula, Chukotka Peninsula or Chukotski Peninsula , at about 66° N 172° W, is the northeastern extremity of Asia. Its eastern end is at Cape Dezhnev near the village of Uelen. It is bordered by the Chukchi Sea to the north, the Bering Sea to the south, and the Bering Strait to the...
region in extreme NE SiberiaSiberiaSiberia is an extensive region constituting almost all of Northern Asia. Comprising the central and eastern portion of the Russian Federation, it was part of the Soviet Union from its beginning, as its predecessor states, the Tsardom of Russia and the Russian Empire, conquered it during the 16th...
- Lanius excubitor invictus – N Alberta
- Larger and paler than borealis, paralleling homeyeri compared to excubitor.
Description
An adult Great Grey Shrike is usually around 24 to 25 cm (9.4 to 9.8 in) long—about as large as a big thrushThrush (bird)
The thrushes, family Turdidae, are a group of passerine birds that occur worldwide.-Characteristics:Thrushes are plump, soft-plumaged, small to medium-sized birds, inhabiting wooded areas, and often feed on the ground or eat small fruit. The smallest thrush may be the Forest Rock-thrush, at and...
—and weighs around 60 to 70 g (2.1 to 2.5 oz), although some subspecies
Subspecies
Subspecies in biological classification, is either a taxonomic rank subordinate to species, ora taxonomic unit in that rank . A subspecies cannot be recognized in isolation: a species will either be recognized as having no subspecies at all or two or more, never just one...
are noticeably smaller or larger, and even in the nominate subspecies adult weights between 48 and 81 g (1.7 to 3 oz) are recorded. The wings are around 11.4 cm (4.5 in) and the tail around 10.9 cm (4.3 in) long in the nominate subspecies, its bill measures about 23 mm (0.9 in) from tip to skull, and the tarsometatarsus
Tarsometatarsus
The tarsometatarsus is a bone that is found in the lower leg of certain tetrapods, namely birds.It is formed from the fusion of several bones found in other types of animals, and homologous to the mammalian tarsal and metatarsal bones...
part of its "legs" (actually feet) is around 27.4 mm (1.1 in) long.
Beak
The beak, bill or rostrum is an external anatomical structure of birds which is used for eating and for grooming, manipulating objects, killing prey, fighting, probing for food, courtship and feeding young...
through the eye to the ear coverts; the area immediately above the beak is grey. The scapulars (shoulder feathers) are white, and the wings are black with a white bar made up by the bases of the primary remiges, continuing slightly offset onto the bases of the secondary remiges in some regions. The tail is black, long, and pointed at the tip; the outer rectrices have white outer vane
Vane
Vane may refer to:* Cooper vane* Vane anemometer* Weather vaneA vane is also each of the parts besides the shaft in a pennaceous feather...
s. The underparts are white, slightly tinged with grey in most subspecies
Subspecies
Subspecies in biological classification, is either a taxonomic rank subordinate to species, ora taxonomic unit in that rank . A subspecies cannot be recognized in isolation: a species will either be recognized as having no subspecies at all or two or more, never just one...
. In particular the breast is usually darker and sometimes browner than the rest of the light underside, and may appear as an indistinct band between the lighter belly and white throat. In the subspecies around the North Pacific in particular and in females elsewhere too, there may be faint brownish bars on the breast. The bill is large and hooked at the tip and coloured nearly black, but pale at the base of the under mandible
Mandible
The mandible pronunciation or inferior maxillary bone forms the lower jaw and holds the lower teeth in place...
(though the extent varies season
Season
A season is a division of the year, marked by changes in weather, ecology, and hours of daylight.Seasons result from the yearly revolution of the Earth around the Sun and the tilt of the Earth's axis relative to the plane of revolution...
ally). The legs and feet are blackish.
Males and females are about the same size, and do not differ conspicuously in appearance except by direct comparison. In the female the underparts are greyer and are usually visibly barred greyish-brown, and the white wing and tail markings are characteristically less in extent (though this is rarely clearly visible except in flight). Fledge
Fledge
Fledge is the stage in a young bird's life when the feathers and wing muscles are sufficiently developed for flight. It also describes the act of a chick's parents raising it to a fully grown state...
d young birds are heavily tinged greyish-brown all over, with barring on the upperside and indistinct buff
Buff (colour)
Buff is a pale yellow-brown colour that got its name from the colour of buff leather.Displayed on the right is the colour buff.EtymologyAccording to the Oxford English Dictionary, buff as a descriptor of a colour was first used in the London Gazette of 1686, describing a uniform to be "A Red Coat...
y-white markings. The tips of the tertiary remiges and the wing coverts are also buffy, with a black band in the latter. In the North American subspecies borealis, the fledglings are tinged quite brown indeed on upperside and wings, and have sharp and dark underside bars. In Eurasia, fledglings moult
Moult
In biology, moulting or molting , also known as sloughing, shedding, or for some species, ecdysis, is the manner in which an animal routinely casts off a part of its body , either at specific times of year, or at specific points in its life cycle.Moulting can involve the epidermis , pelage...
into a female-like plumage with the tertiary bars usually remaining in autumn. Across its range, the young acquire the adult plumage in their first spring.
Vocalisations
The male's songBird song
Bird vocalization includes both bird calls and bird songs. In non-technical use, bird songs are the bird sounds that are melodious to the human ear. In ornithology and birding, songs are distinguished by function from calls.-Definition:The distinction between songs and calls is based upon...
consists of short pleasant warbling strophes, interspersed with fluid whistles. The individual phrases may go like tu-tu-krr-pree-pree or trr-turit trr-turit.... To announce that it has become aware of someone straying into its territory – be it a female or male of its species or a large mammal
Mammal
Mammals are members of a class of air-breathing vertebrate animals characterised by the possession of endothermy, hair, three middle ear bones, and mammary glands functional in mothers with young...
– it gives long shrill raspy whistles like trrii(u) or (t')kwiiet. To announce to females, it often mixes these whistles with a strophe of song. A softer whistle goes like trüü(t). These whistles are also used in duets between mates in winter and neighbors in the breeding season. Various contact calls have been described as chlie(p), gihrrr, kwä or wuut. These are frequently heard during courtship, interspersed with song phrases as the harsh whistles are in pre-courtship. The song becomes softer and more warbling as the male shows the female around his territory, and at potential nest sites the male gives a lively chatter containing fluting tli-tli, prrr trills and kwiw...püh calls.
When disturbed its alarm note is a harsh jay
Jay
The jays are several species of medium-sized, usually colorful and noisy, passerine birds in the crow family Corvidae. The names jay and magpie are somewhat interchangeable, and the evolutionary relationships are rather complex...
-like k(w)eee, greee or jaaa, often repeated twice. The more excited the birds become, the higher and faster the calls get, via chek-chek-chek to a rattle trr-trr-trr or an explosive aak-aak-aak. Bird of prey
Bird of prey
Birds of prey are birds that hunt for food primarily on the wing, using their keen senses, especially vision. They are defined as birds that primarily hunt vertebrates, including other birds. Their talons and beaks tend to be relatively large, powerful and adapted for tearing and/or piercing flesh....
alert is given with a whistle breezeek. Knuk calls are given with adults confronted with a potential threat to their young. To beg for food – young to adults or pairmembers to each other –, rows of waik calls are given. This species sometimes tries to attract small songbirds by mimicking
Aggressive mimicry
Aggressive mimicry is a form of mimicry where predators, parasites or parasitoids share similar signals with a harmless model, allowing them to avoid being correctly identified by their prey or host...
their calls, so it may attempt to catch them for food.
Similar species
Southern Grey Shrike
The Southern Grey Shrike, Lanius meridionalis, is a member of the shrike family.It is closely related to the Great Grey Shrike, Lanius excubitor, with which it used to be considered conspecific; where they co-occur, they do not interbreed and are separated by choice of habitat.The race L. m....
(L. meridionalis) was formerly included in the Great Grey Shrike as subspecies
Subspecies
Subspecies in biological classification, is either a taxonomic rank subordinate to species, ora taxonomic unit in that rank . A subspecies cannot be recognized in isolation: a species will either be recognized as having no subspecies at all or two or more, never just one...
. It occurs in SW Europe (Iberian Peninsula
Iberian Peninsula
The Iberian Peninsula , sometimes called Iberia, is located in the extreme southwest of Europe and includes the modern-day sovereign states of Spain, Portugal and Andorra, as well as the British Overseas Territory of Gibraltar...
and France) southwards to Africa around the Sahara
Sahara
The Sahara is the world's second largest desert, after Antarctica. At over , it covers most of Northern Africa, making it almost as large as Europe or the United States. The Sahara stretches from the Red Sea, including parts of the Mediterranean coasts, to the outskirts of the Atlantic Ocean...
, and also in Central Asia. It prefers different habitat
Habitat (ecology)
A habitat is an ecological or environmental area that is inhabited by a particular species of animal, plant or other type of organism...
– lightly wooded grassland in the Great, more arid
Arid
A region is said to be arid when it is characterized by a severe lack of available water, to the extent of hindering or even preventing the growth and development of plant and animal life...
shrubland
Shrubland
Shrubland, scrubland, scrub or brush is a plant community characterized by vegetation dominated by shrubs, often also including grasses, herbs, and geophytes. Shrubland may either occur naturally or be the result of human activity...
in the Southern Grey Shrike – and where the species' ranges overlap, they do not hybridize at present (though they may have done so in past millennia).
Chinese Grey Shrike
The Chinese Grey Shrike is a species of bird in the Laniidae family.It is found in China, Japan, North Korea, South Korea, Mongolia, and Russia.Its natural habitat is temperate forests.-External links:*...
(L. sphenocerus) from East Asia
East Asia
East Asia or Eastern Asia is a subregion of Asia that can be defined in either geographical or cultural terms...
and the Loggerhead Shrike
Loggerhead Shrike
The Loggerhead Shrike is a passerine bird. It is the only member of the shrike family endemic to North America; the related Northern Shrike occurs north of its range but also in the Palearctic....
(L. ludovicianus) from North America. The Northern Grey Shrike is sympatric in winter quarters with each of its three close relatives at the north of their range. Their overall coloration is – apparently plesiomorphically – shared in sub-Saharan Africa
Sub-Saharan Africa
Sub-Saharan Africa as a geographical term refers to the area of the African continent which lies south of the Sahara. A political definition of Sub-Saharan Africa, instead, covers all African countries which are fully or partially located south of the Sahara...
by the somewhat more distantly related Grey-backed Fiscal
Grey-backed Fiscal
The Grey-backed Fiscal is a species of bird in the Laniidae family.It is found in Burundi, Cameroon, Central African Republic, Chad, Democratic Republic of the Congo, Ethiopia, Kenya, Mali, Mauritania, Nigeria, Rwanda, Sudan, Tanzania, and Uganda.Its natural habitats are dry savanna and...
(L. excubitoroides) which is found from the Sahel
Sahel
The Sahel is the ecoclimatic and biogeographic zone of transition between the Sahara desert in the North and the Sudanian Savannas in the south.It stretches across the North African continent between the Atlantic Ocean and the Red Sea....
eastwards, and Mackinnon's Fiscal (L. mackinnoni) of the Congo Basin
Congo Basin
The Congo Basin is the sedimentary basin that is the drainage of the Congo River of west equatorial Africa. The basin begins in the highlands of the East African Rift system with input from the Chambeshi River, the Uele and Ubangi Rivers in the upper reaches and the Lualaba River draining wetlands...
region. The Lesser Grey Shrike
Lesser Grey Shrike
The Lesser Grey Shrike is a member of the shrike family Laniidae.It is similar in appearance to the Great Grey Shrike Lanius excubitor and the Southern Grey Shrike L. meridionalis...
(L. minor, Balkans
Balkans
The Balkans is a geopolitical and cultural region of southeastern Europe...
to Central Asia) seems to be quite distinct indeed and is sympatric with the Grey Shrike superspecies
Superspecies
A superspecies is a group of at least two more or less distinctive species with approximately parapatric distributions. Not all species complexes, whether cryptices or ring species are superspecies, and vice versa, but many are...
between Eastern Europe and Central Asia; it may be more closely related to the small brown shrikes and resemble the bold, aggressive and hard-to-catch grey shrikes because of Batesian mimicry
Batesian mimicry
Batesian mimicry is a form of mimicry typified by a situation where a harmless species has evolved to imitate the warning signals of a harmful species directed at a common predator...
.
The Southern Grey Shrike is clearer and usually darker grey above, and not tinged grey but often decidedly pinkish on the belly and particular breast; the white "eyebrow" extends to over the beak, which has typically a larger pale base. The barring pattern is less developed at all ages, hardly ever present even in females, and slighter in the otherwise very similar fledgling
Fledgling
Fledgling or Fledglings may refer to:* Curtiss Fledgling, a trainer aircraft* Fergie's Fledglings, a group of Manchester United players recruited under the management of Alex Ferguson...
s.
East Asian L. excubitor are barely sympatric with the Chinese Grey Shrike. The latter is larger and generally differs from the Northern species as the Southern does, and in addition has much larger white areas in wings and tail.
The Loggerhead Shrike is hard to distinguish, but the proportion of the head to the beak (which seems stubby in L. ludovicianus by comparison and is all-dark) is usually reliable. Indeed, the term "loggerhead
Loggerhead
-Locations:* Loggerhead Key, the largest islet in the Dry Tortugas, Florida* Loggerheads, Denbighshire, a village in Denbighshire, Wales* Loggerheads, Staffordshire, a small village in north Staffordshire, England...
" refers to the relatively larger head of the southern species.
The Lesser Grey Shrike is a smaller and comparatively short-tailed bird. It can best recognized by its rather large black area above the bill, almost reaching to the forehead and without a white stripe above it. In flight, the wide instead of pointed black tail end of L. minor is characteristic. The African species are completely allopatric with L. excubitor; they lack white scapulars (Grey-backed Fiscal) or wingspots (Mackinnon's Fiscal) and differ in some other details, particularly the tail pattern.
Distribution and habitat
The Great Grey Shrike occurs throughout most temperate and subarcticSubarctic
The Subarctic is a region in the Northern Hemisphere immediately south of the true Arctic and covering much of Alaska, Canada, the north of Scandinavia, Siberia, and northern Mongolia...
regions of the Northern Hemisphere. Generally, its breeding range is limited to areas north of 50° northern latitude in Eurasia, and north of 55° northern latitude in North America. In the high mountains of the Altai-Tian Shan
Tian Shan
The Tian Shan , also spelled Tien Shan, is a large mountain system located in Central Asia. The highest peak in the Tian Shan is Victory Peak , ....
region, it ranges south perhaps as far as 42° northern latitude. Its northern limit is generally 70° northern latitude, except in eastern Canada (Quebec
Quebec
Quebec or is a province in east-central Canada. It is the only Canadian province with a predominantly French-speaking population and the only one whose sole official language is French at the provincial level....
) where it only reaches up to about 60° northern latitude. It is only found as a vagrant in Iceland
Iceland
Iceland , described as the Republic of Iceland, is a Nordic and European island country in the North Atlantic Ocean, on the Mid-Atlantic Ridge. Iceland also refers to the main island of the country, which contains almost all the population and almost all the land area. The country has a population...
, the British Isles
British Isles
The British Isles are a group of islands off the northwest coast of continental Europe that include the islands of Great Britain and Ireland and over six thousand smaller isles. There are two sovereign states located on the islands: the United Kingdom of Great Britain and Northern Ireland and...
, the Mediterranean region (excluding the Iberian Peninsula
Iberian Peninsula
The Iberian Peninsula , sometimes called Iberia, is located in the extreme southwest of Europe and includes the modern-day sovereign states of Spain, Portugal and Andorra, as well as the British Overseas Territory of Gibraltar...
and perhaps Romania
Romania
Romania is a country located at the crossroads of Central and Southeastern Europe, on the Lower Danube, within and outside the Carpathian arch, bordering on the Black Sea...
but including Cyprus
Cyprus
Cyprus , officially the Republic of Cyprus , is a Eurasian island country, member of the European Union, in the Eastern Mediterranean, east of Greece, south of Turkey, west of Syria and north of Egypt. It is the third largest island in the Mediterranean Sea.The earliest known human activity on the...
), and Korea
Korea
Korea ) is an East Asian geographic region that is currently divided into two separate sovereign states — North Korea and South Korea. Located on the Korean Peninsula, Korea is bordered by the People's Republic of China to the northwest, Russia to the northeast, and is separated from Japan to the...
. There do not appear to be breeding records from the entire Kamchatka Peninsula
Kamchatka Peninsula
The Kamchatka Peninsula is a peninsula in the Russian Far East, with an area of . It lies between the Pacific Ocean to the east and the Sea of Okhotsk to the west...
; in Switzerland, Czechia and southern Germany small populations were found in the mid-20th century but have declined or even disappeared since then.
Except for the subspecies
Subspecies
Subspecies in biological classification, is either a taxonomic rank subordinate to species, ora taxonomic unit in that rank . A subspecies cannot be recognized in isolation: a species will either be recognized as having no subspecies at all or two or more, never just one...
bianchii which is largely all-year resident, and subspecies excubitor in the temperate European parts of its range with their mild maritime climate, the species is a short-distance migrant
Bird migration
Bird migration is the regular seasonal journey undertaken by many species of birds. Bird movements include those made in response to changes in food availability, habitat or weather. Sometimes, journeys are not termed "true migration" because they are irregular or in only one direction...
. The migrations are triggered by scarcity of food and therefore, according to prey population levels, the winter range might little extend south beyond the breeding range, or be entirely parapatric to it. The populations of the Central Asian mountains mostly migrate downslope rather than southwards. Females are more prone to migration than males; they do not appear to migrate, on average, longer or shorter distances than males, and consequently are the dominant sex in many parts of the winter range. Birds leave for winter quarters a more or less short time after breeding – July to October, with most birds staying to September – and return to nest mainly in March/April, but some only arrive in May. In recent decades, the number of birds remaining on the breeding grounds all year has been noted to increase e.g. in Fennoscandia
Fennoscandia
Fennoscandia and Fenno-Scandinavia are geographic and geological terms used to describe the Scandinavian Peninsula, the Kola Peninsula, Karelia and Finland...
, whereas for example borealis seems to be as rare a winter visitor in northern Ohio
Ohio
Ohio is a Midwestern state in the United States. The 34th largest state by area in the U.S.,it is the 7th‑most populous with over 11.5 million residents, containing several major American cities and seven metropolitan areas with populations of 500,000 or more.The state's capital is Columbus...
as it was a century ago.
The preferred habitat
Habitat (ecology)
A habitat is an ecological or environmental area that is inhabited by a particular species of animal, plant or other type of organism...
is generally open grassland
Grassland
Grasslands are areas where the vegetation is dominated by grasses and other herbaceous plants . However, sedge and rush families can also be found. Grasslands occur naturally on all continents except Antarctica...
, perhaps with shrub
Shrub
A shrub or bush is distinguished from a tree by its multiple stems and shorter height, usually under 5–6 m tall. A large number of plants may become either shrubs or trees, depending on the growing conditions they experience...
s interspersed, and adjacent lookout points. These are normally trees – at forest edges in much of the habitat, but single trees or small stands at the taiga
Taiga
Taiga , also known as the boreal forest, is a biome characterized by coniferous forests.Taiga is the world's largest terrestrial biome. In North America it covers most of inland Canada and Alaska as well as parts of the extreme northern continental United States and is known as the Northwoods...
-tundra
Tundra
In physical geography, tundra is a biome where the tree growth is hindered by low temperatures and short growing seasons. The term tundra comes through Russian тундра from the Kildin Sami word tūndâr "uplands," "treeless mountain tract." There are three types of tundra: Arctic tundra, alpine...
border. In steppe
Steppe
In physical geography, steppe is an ecoregion, in the montane grasslands and shrublands and temperate grasslands, savannas, and shrublands biomes, characterized by grassland plains without trees apart from those near rivers and lakes...
, it will utilize any isolated perch, be it fence posts, power line
Power Line
Power Line is an American political blog, providing news and commentary from a conservative point-of-view. It was originally written by three lawyers who attended Dartmouth College together: John H. Hinderaker, Scott W. Johnson, and Paul Mirengoff...
s or rocks. In general, some 5–15 perching sites per hectar habitat seem to be required. It avoids low grassland with no lookouts and nesting opportunities (trees or large shrubs), as well as dense forest with no hunting ground. Apart from grassland, the birds will utilize a variety of hunting habitats, including bog
Bog
A bog, quagmire or mire is a wetland that accumulates acidic peat, a deposit of dead plant material—often mosses or, in Arctic climates, lichens....
s, clearing
Clearing
Clearing may refer to:* Glade , a tract of land with few or no trees in the middle of a wooded area* Deforestation, the clearing away of trees to make farmland* Clearing , the process of settling a transaction after committing to it...
s or non-industrially farmed fields
Field (agriculture)
In agriculture, the word field refers generally to an area of land enclosed or otherwise and used for agricultural purposes such as:* Cultivating crops* Usage as a paddock or, generally, an enclosure of livestock...
. Breeding birds appear to have different microhabitat desires, but little detail is known yet.
Behaviour
This species is territorial, but likes to breed in dispersed groups of a good half-dozen adults. It is not known to what extent the birds in such groups are related. In the temperate parts of its range, groups are perhaps 5 km (3.1 mi) apart, while individual territories within each group may be as small as 20 ha (49.4 acre) but more typically are about twice that size. In less hospitable climes, territories may be more than 350 ha (1.4 sq mi) large. Throughout the breeding season, in prime habitat territories are held by mated pairs and single males looking for a partner. In less productive habitat, "floaterFloater (disambiguation)
A floater is a shadow-like shape that appears singly or together with several others in the field of vision of some individuals.Floater may also mean:*Floater , a band based in Portland, Oregon*The Floaters, an R&B singing group of the 1970s...
s" hold territories more ephemeral
Ephemeral
Ephemeral things are transitory, existing only briefly. Typically the term is used to describe objects found in nature, although it can describe a wide range of things....
ly. This leads to shifts in population density
Population density
Population density is a measurement of population per unit area or unit volume. It is frequently applied to living organisms, and particularly to humans...
between regions, as "floaters" move between groups of territorial birds in search of a bountiful unclaimed territory to settle down and/or a partner to mate with. On the wintering grounds, pairs separate to account for the lower amount of food available at that time, but if both members migrate they tend to have their wintering grounds not far apart. As it seems, once an individual Great Grey Shrike has found a wintering territory it likes, it will return there subsequently and perhaps even try to defend it against competitors just like a summer territory. Throughout the year, the birds regularly but briefly move through a range up to three times larger than their territory; this is tolerated by territory owners in winter more easily than in summer, and the parts of Europe where all-year residents and winter visitors co-occur typically have population densities around 8 birds/km2 (about 30 per square mile) and occasionally more in winter.
Before and after the nesting season, groups of breeding birds will sometimes initiate gatherings; these seem to occur at the boundary of the group's combined range or in the unclaimed land separating it from neighboring groups. The initiation signal is a conspicuous display flight given by a bird surveying its territory: it spirals tens of meters/yards high into the air, usually briefly does a fluttering hover at the top of the spiral, and then glides down. Group neighbors will respond by performing the same type of flight, and eventually about half the group's members will depart to the meeting location where they will spend several tens of minutes – sometimes more than one hour – chattering, calling, duetting, and excitedly moving about the meeting site (which typically is some small tree or shrubbery). In winter, birds will often assemble in small groups and roost together, particularly to keep warm during the night; this is apparently not initiated with a specific assembly display however.
The flight of the Great Grey Shrike is undulating and rather heavy, but its dash is straight and determined. It is, as noted above, also capable of hover
Hover
Hover may refer to:*Hovering , the process by which an object is suspended by a physical force against gravity, in a stable position without solid physical contactIn transport* Hover , nearly stationary flight in a helicopter...
flights, which last briefly but may be repeated time after time because of the birds' considerable stamina. It will usually stay low above the ground in flight, approaching perches from below and landing in an upward swoop. In social interactions, birds signal an aggressive stance by a bold upright posture, fanning and then flicking the tail and eventually the wings also as the bird gets more excited. It signals its readiness to strike at an intruder by shifting to a horizontal
Horizontal plane
In geometry, physics, astronomy, geography, and related sciences, a plane is said to be horizontal at a given point if it is perpendicular to the gradient of the gravity field at that point— in other words, if apparent gravity makes a plumb bob hang perpendicular to the plane at that point.In...
pose and fluffing its feathers, raising them into a small crest along the top of the head. Birds appease conspecifics by head-turns away from them (if close by), or by imitating the crouching fluttering pose and calls given by fledgling
Fledgling
Fledgling or Fledglings may refer to:* Curtiss Fledgling, a trainer aircraft* Fergie's Fledglings, a group of Manchester United players recruited under the management of Alex Ferguson...
s begging for food (if sitting father apart). The submission
Submission
Submission is the acknowledgement of the legitimacy of the power of one's superior or superiors.Submission may also refer to:* Submission/Submitter , an Islamic organisation...
gesture to prevent an imminent attack by a conspecific is pointing the beak
Beak
The beak, bill or rostrum is an external anatomical structure of birds which is used for eating and for grooming, manipulating objects, killing prey, fighting, probing for food, courtship and feeding young...
straight up.
North American fledgling
Fledgling
Fledgling or Fledglings may refer to:* Curtiss Fledgling, a trainer aircraft* Fergie's Fledglings, a group of Manchester United players recruited under the management of Alex Ferguson...
s apparently have one moult
Moult
In biology, moulting or molting , also known as sloughing, shedding, or for some species, ecdysis, is the manner in which an animal routinely casts off a part of its body , either at specific times of year, or at specific points in its life cycle.Moulting can involve the epidermis , pelage...
in their first spring only, in which they acquire adult plumage. Eurasian ones moult part of their juvenile plumage before their first winter, and the rest in spring. Adults moult on their breeding grounds before going on migration, or before the depth of winter if they are resident. Sometimes adults also seem to moult some feathers before attempting to breed. As moult requires a considerable investment of energy, some significant evolution
Evolution
Evolution is any change across successive generations in the heritable characteristics of biological populations. Evolutionary processes give rise to diversity at every level of biological organisation, including species, individual organisms and molecules such as DNA and proteins.Life on Earth...
ary benefits to offset this are likely. Reducing feather wear and parasite load, moulting can make a bird more physically attractive and healthy, and may thus increase its chance of successful reproduction. The phenomenon is not well understood, however.
Food and feeding
Vertebrate
Vertebrates are animals that are members of the subphylum Vertebrata . Vertebrates are the largest group of chordates, with currently about 58,000 species described. Vertebrates include the jawless fishes, bony fishes, sharks and rays, amphibians, reptiles, mammals, and birds...
s and large invertebrate
Invertebrate
An invertebrate is an animal without a backbone. The group includes 97% of all animal species – all animals except those in the chordate subphylum Vertebrata .Invertebrates form a paraphyletic group...
s. To hunt, this bird perches on the topmost branch of a tree, telegraph pole or similar elevated spot in a characteristic upright stance some meters/yards (at least one and up to 18 m/20 yd) above ground. Alternatively, it may scan the grassland below from flight, essentially staying in one place during prolonged bouts of mainly hovering flight that may last up to 20 minutes. The keen eye of the watchful "sentinel" misses nothing that moves. It will drop down in a light glide for terrestrial
Terrestrial animal
Terrestrial animals are animals that live predominantly or entirely on land , as compared with aquatic animals, which live predominantly or entirely in the water , or amphibians, which rely on a combination of aquatic and terrestrial habitats...
prey or swoop hawk
Hawk
The term hawk can be used in several ways:* In strict usage in Australia and Africa, to mean any of the species in the subfamily Accipitrinae, which comprises the genera Accipiter, Micronisus, Melierax, Urotriorchis and Megatriorchis. The large and widespread Accipiter genus includes goshawks,...
-like on a flying insect
Insect
Insects are a class of living creatures within the arthropods that have a chitinous exoskeleton, a three-part body , three pairs of jointed legs, compound eyes, and two antennae...
. Small birds are sometimes caught in flight too, usually by approaching them from below and behind and seizing their feet with the beak. If no prey ventures out in the open, Great Grey Shrikes will rummage through the undergrowth or sit near to hiding places and flash their white wing and tail markings to scare small animals into coming out. As noted above, it will sometimes mimic
Aggressive mimicry
Aggressive mimicry is a form of mimicry where predators, parasites or parasitoids share similar signals with a harmless model, allowing them to avoid being correctly identified by their prey or host...
songbirds to entice them to come within striking distance.
Typically, at least half the prey biomass
Biomass
Biomass, as a renewable energy source, is biological material from living, or recently living organisms. As an energy source, biomass can either be used directly, or converted into other energy products such as biofuel....
is made up from small rodent
Rodent
Rodentia is an order of mammals also known as rodents, characterised by two continuously growing incisors in the upper and lower jaws which must be kept short by gnawing....
s from the Cricetidae
Cricetidae
The Cricetidae are a family of rodents in the large and complex superfamily Muroidea. It includes true hamsters, voles, lemmings, and New World rats and mice...
(vole
Vole
A vole is a small rodent resembling a mouse but with a stouter body, a shorter hairy tail, a slightly rounder head, smaller ears and eyes, and differently formed molars . There are approximately 155 species of voles. They are sometimes known as meadow mice or field mice in North America...
s, American mice
MICE
-Fiction:*Mice , alien species in The Hitchhiker's Guide to the Galaxy*The Mice -Acronyms:* "Meetings, Incentives, Conferencing, Exhibitions", facilities terminology for events...
and sometimes lemming
Lemming
Lemmings are small rodents, usually found in or near the Arctic, in tundra biomes. They are subniveal animals, and together with voles and muskrats, they make up the subfamily Arvicolinae , which forms part of the largest mammal radiation by far, the superfamily Muroidea, which also includes rats,...
s) and Murinae
Murinae
The Old World rats and mice, part of the subfamily Murinae in the family Muridae, comprise at least 519 species. This subfamily is larger than all mammal families except the Cricetidae and Muridae, and is larger than all mammal orders except the bats and the remainder of the...
(Eurasian mice and sometimes young Eurasian rat
Rat
Rats are various medium-sized, long-tailed rodents of the superfamily Muroidea. "True rats" are members of the genus Rattus, the most important of which to humans are the black rat, Rattus rattus, and the brown rat, Rattus norvegicus...
s). Shrew
Shrew
A shrew or shrew mouse is a small molelike mammal classified in the order Soricomorpha. True shrews are also not to be confused with West Indies shrews, treeshrews, otter shrews, or elephant shrews, which belong to different families or orders.Although its external appearance is generally that of...
s, songbird, lizard
Lizard
Lizards are a widespread group of squamate reptiles, with nearly 3800 species, ranging across all continents except Antarctica as well as most oceanic island chains...
s, and frog
Frog
Frogs are amphibians in the order Anura , formerly referred to as Salientia . Most frogs are characterized by a short body, webbed digits , protruding eyes and the absence of a tail...
s and toad
Toad
A toad is any of a number of species of amphibians in the order Anura characterized by dry, leathery skin , short legs, and snoat-like parotoid glands...
s (typically as tadpole
Tadpole
A tadpole or polliwog is the wholly aquatic larval stage in the life cycle of an amphibian, particularly that of a frog or toad.- Appellation :...
s) make up most of the remaining vertebrate prey. Birds are generally of little importance however, except in spring when male songbirds are engaged in courtship display
Courtship display
Courtship display is a special, sometimes ritualised, set of behaviours which some animals perform as part of courtship. Courtship behaviours can include special calls, postures, and movements, and may involve special plumage, bright colours or other ornamentation. A good example is the 'dancing'...
and often rather oblivious of their surroundings, in late summer when inexperienced fledgling
Fledgling
Fledgling or Fledglings may refer to:* Curtiss Fledgling, a trainer aircraft* Fergie's Fledglings, a group of Manchester United players recruited under the management of Alex Ferguson...
s abound, and in winter when most small mammals hibernate. Occasionally bat
Bat
Bats are mammals of the order Chiroptera "hand" and pteron "wing") whose forelimbs form webbed wings, making them the only mammals naturally capable of true and sustained flight. By contrast, other mammals said to fly, such as flying squirrels, gliding possums, and colugos, glide rather than fly,...
s, newt
Newt
A newt is an aquatic amphibian of the family Salamandridae, although not all aquatic salamanders are considered newts. Newts are classified in the subfamily Pleurodelinae of the family Salamandridae, and are found in North America, Europe and Asia...
s and salamander
Salamander
Salamander is a common name of approximately 500 species of amphibians. They are typically characterized by a superficially lizard-like appearance, with their slender bodies, short noses, and long tails. All known fossils and extinct species fall under the order Caudata, while sometimes the extant...
s, and even fish
Fish
Fish are a paraphyletic group of organisms that consist of all gill-bearing aquatic vertebrate animals that lack limbs with digits. Included in this definition are the living hagfish, lampreys, and cartilaginous and bony fish, as well as various extinct related groups...
are eaten. Prey animals may exceptionally be almost as large as the birds themselves, for example chicks of the Willow Grouse
Willow Grouse
The Willow Ptarmigan , also known as the Willow Grouse, is a bird of the grouse subfamily. It is a sedentary species, breeding in birch and other forests and moorlands in the tundra of Scandinavia, Siberia, Alaska, northern Canada, in particular the province of Newfoundland and Labrador...
(Lagopus lagopus) or a young Ermine
Ermine
Ermine has several uses:* A common name for the stoat * The white fur and black tail end of this animal, which is historically worn by and associated with royalty and high officials...
(Mustela nivalis). Large arthropod
Arthropod
An arthropod is an invertebrate animal having an exoskeleton , a segmented body, and jointed appendages. Arthropods are members of the phylum Arthropoda , and include the insects, arachnids, crustaceans, and others...
s are the secondmost important prey by quantity, though not by biomass; in the latter respect they are only a bit more important than birds, except as food for nestlings where they usually form a substantial part of the diet. Most important among invertebrate prey are insect
Insect
Insects are a class of living creatures within the arthropods that have a chitinous exoskeleton, a three-part body , three pairs of jointed legs, compound eyes, and two antennae...
s, especially beetle
Beetle
Coleoptera is an order of insects commonly called beetles. The word "coleoptera" is from the Greek , koleos, "sheath"; and , pteron, "wing", thus "sheathed wing". Coleoptera contains more species than any other order, constituting almost 25% of all known life-forms...
s (Coleoptera), cricket
Cricket
Cricket is a bat-and-ball game played between two teams of 11 players on an oval-shaped field, at the centre of which is a rectangular 22-yard long pitch. One team bats, trying to score as many runs as possible while the other team bowls and fields, trying to dismiss the batsmen and thus limit the...
s and grasshoppers
Grasshoppers
Grasshoppers are insects of the suborder Caelifera.Grasshoppers may also refer to:* Grasshopper , a Hong Kong-based musical group* Grasshopper Club Zürich, a Swiss football club...
(Orthoptera
Orthoptera
Orthoptera is an order of insects with paurometabolous or incomplete metamorphosis, including the grasshoppers, crickets and locusts.Many insects in this order produce sound by rubbing their wings against each other or their legs, the wings or legs containing rows of corrugated bumps...
), and bumblebee
Bumblebee
A bumble bee is any member of the bee genus Bombus, in the family Apidae. There are over 250 known species, existing primarily in the Northern Hemisphere although they are common in New Zealand and in the Australian state of Tasmania.Bumble bees are social insects that are characterised by black...
s and wasp
Wasp
The term wasp is typically defined as any insect of the order Hymenoptera and suborder Apocrita that is neither a bee nor an ant. Almost every pest insect species has at least one wasp species that preys upon it or parasitizes it, making wasps critically important in natural control of their...
s (Hymenoptera
Hymenoptera
Hymenoptera is one of the largest orders of insects, comprising the sawflies, wasps, bees and ants. There are over 130,000 recognized species, with many more remaining to be described. The name refers to the heavy wings of the insects, and is derived from the Ancient Greek ὑμήν : membrane and...
). Invertebrate prey of minor importance are spider
Spider
Spiders are air-breathing arthropods that have eight legs, and chelicerae with fangs that inject venom. They are the largest order of arachnids and rank seventh in total species diversity among all other groups of organisms...
s and scorpion
Scorpion
Scorpions are predatory arthropod animals of the order Scorpiones within the class Arachnida. They have eight legs and are easily recognized by the pair of grasping claws and the narrow, segmented tail, often carried in a characteristic forward curve over the back, ending with a venomous stinger...
s (Arachnida), crayfish
Crayfish
Crayfish, crawfish, or crawdads – members of the superfamilies Astacoidea and Parastacoidea – are freshwater crustaceans resembling small lobsters, to which they are related...
and isopods (Crustacea), snail
Snail
Snail is a common name applied to most of the members of the molluscan class Gastropoda that have coiled shells in the adult stage. When the word is used in its most general sense, it includes sea snails, land snails and freshwater snails. The word snail without any qualifier is however more often...
s, and oligochaete worms. Carrion
Carrion
Carrion refers to the carcass of a dead animal. Carrion is an important food source for large carnivores and omnivores in most ecosystems. Examples of carrion-eaters include vultures, hawks, eagles, hyenas, Virginia Opossum, Tasmanian Devils, coyotes, Komodo dragons, and burying beetles...
and berries are rarely if ever eaten; though it might occasionally plunder songbird nests this is not well documented and it is not known to eat egg
Egg (biology)
An egg is an organic vessel in which an embryo first begins to develop. In most birds, reptiles, insects, molluscs, fish, and monotremes, an egg is the zygote, resulting from fertilization of the ovum, which is expelled from the body and permitted to develop outside the body until the developing...
s.
Prey is killed by hitting it with the hooked beak, aiming for the skull in vertebrates. If too large to swallow in one or a few chunks, it is transported to a feeding site by carrying it in the beak or (if too large) in the feet. The feet are not suited for tearing up prey, however. It is rather impaled upon a sharp point – thorn
Thorns, spines, and prickles
In botanical morphology, thorns, spines, and prickles are hard structures with sharp, or at least pointed, ends. In spite of this common feature, they differ in their growth and development on the plant; they are modified versions of different plant organs, stems, stipules, leaf veins, or hairs...
s or the barbs of barbed wire
Barbed wire
Barbed wire, also known as barb wire , is a type of fencing wire constructed with sharp edges or points arranged at intervals along the strand. It is used to construct inexpensive fences and is used atop walls surrounding secured property...
– or wedged firmly between forking branch
Branch
A branch or tree branch is a woody structural member connected to but not part of the central trunk of a tree...
es. Thus secured, the food can be ripped into bite-sized pieces with the beak. Orthoptera that the birds have recognized as containing noxious chemicals are left impaled in the larder for several days, until the chemicals that usually deter predators have been degraded. Great Grey Shrikes have also been observed to impale Common Toad
Common Toad
The common toad or European toad is an amphibian widespread throughout Europe, with the exception of Iceland, Ireland and some Mediterranean islands...
s (Bufo bufo) and skin
Skinning
Skinning, a gerund from the verb to skin, commonly refers to the act of skin removal.The process is usually done with animals, mainly as preparation of the meat beneath and/or use for the fur...
them – by ripping open the back skin and pulling it over the head – to avoid contamination of the meat by the toxic skin secretions. Large bones and similar inedible parts of prey animals are usually not ingested, but smaller ones such as tiny bones or the elytra of beetles are eaten and later regurgitate
Regurgitation (digestion)
Regurgitation is the expulsion of material from the mouth, pharynx, or esophagus, usually characterized by the presence of undigested food or blood.Regurgitation is used by a number of species to feed their young...
d as pellet
Pellet (ornithology)
A pellet, in ornithology, is the mass of undigested parts of a bird's food that some bird species occasionally regurgitate. The contents of a bird's pellet depend on its diet, but can include the exoskeletons of insects, indigestible plant matter, bones, fur, feathers, bills, claws, and teeth...
s.
The basic metabolic rate of the Great Grey Shrike is around 800 milliwatts, or somewhat more than 11 milliwatts per gram of body mass. An adult of this species needs about 50 g (1.8 oz) of prey a day, probably somewhat more in winter. Under most circumstances, this would thus translate to one or two rodent
Rodent
Rodentia is an order of mammals also known as rodents, characterised by two continuously growing incisors in the upper and lower jaws which must be kept short by gnawing....
s, one or two additional vertebrate prey animals (including rodents), and up to a single vertebrate prey item's worth of invertebrates. Surplus food may be impaled for storage. These "larder
Larder
A larder is a cool area for storing food prior to use.Larders were commonplace in houses before the widespread use of the refrigerator.Essential qualities of a larder are that it should be:*as cool as possible*close to food preparation areas...
s" are typically around 1 meter above ground and can be found anywhere within the birds' territory, but tend to be rather in the general vicinity of nest sites than far away from them.
Breeding and life history
Great Grey Shrikes breed during the summer, typically once per year. In exceptionally good conditions, they raise two broods a year, and if the first clutchClutch (eggs)
A clutch of eggs refers to all the eggs produced by birds or reptiles, often at a single time, particularly those laid in a nest.In birds, destruction of a clutch by predators, , results in double-clutching...
is destroyed before hatching they are usually able to produce a second one. Their monogamous pair bond
Pair bond
In biology, a pair bond is the strong affinity that develops in some species between the males and females in a pair, potentially leading to breeding. Pair-bonding is a term coined in the 1940s that is frequently used in sociobiology and evolutionary psychology circles...
is strong during the breeding season and loosens over winter; birds often choose a different mate than the year before. To seek out potential mates, males will venture outside their breeding territories. If a female thus encountered finds a male to her liking, she will visit to see whether they get along well and inspect the nesting sites he can offer. The courtship period is generally longer than in the Southern Grey Shrike
Southern Grey Shrike
The Southern Grey Shrike, Lanius meridionalis, is a member of the shrike family.It is closely related to the Great Grey Shrike, Lanius excubitor, with which it used to be considered conspecific; where they co-occur, they do not interbreed and are separated by choice of habitat.The race L. m....
(L. meridionalis), usually starting about March and lasting to April/May. At first, the female rebuffs the male, only allowing him to feed her. Males give increasingly vocal displays and show off the white markings of the wings in flight and of the tail by fanning it and turning away from the female. He also occasionally turns to sit at a right angle to her. Eventually, the female will join in the male's displays, and the songs will become duets. To feed females and to show off their hunting prowess, males will make their food caches in conspicuous places during this time. When presenting nesting sites, males give the variety of calls described above and jerk their head and fanned tail.
Copulation is typically initiated by the male bringing an attractive prey item to the female. With both giving begging calls, they approach until they are side by side. The male then raises and swings his body left and right a few times, and passes the prey to the female, followed by the actual copulation. The gatherings of neighbor groups (see above) cease when nesting is underway, and when the eggs are nearly ready to lay, the male guards his partner closely, perching higher than her to watch for threats and frequently feeding her. This apparently ensures her physical well-being rather than preventing extra-pair copulations, as neighboring males will stray through each other's territory to snatch a quick fling with the resident females. In this, they have almost a one-in-three chance of success, and consequently the average Grey Shrike nest is very likely to contain offspring of more than one male. Females may deposit their eggs in neighbors' nests, but this seems to occur more rarely; in general, mated females are fairly reclusive after their eggs have started developing. A full clutch
Clutch (eggs)
A clutch of eggs refers to all the eggs produced by birds or reptiles, often at a single time, particularly those laid in a nest.In birds, destruction of a clutch by predators, , results in double-clutching...
of eggs can be produced by a female in about 10–15 days.
Bird nest
A bird nest is the spot in which a bird lays and incubates its eggs and raises its young. Although the term popularly refers to a specific structure made by the bird itself—such as the grassy cup nest of the American Robin or Eurasian Blackbird, or the elaborately woven hanging nest of the...
s are built in April or May more than 1 meter (1 yard) above ground in trees. This height varies according to habitat, but while nests have been found almost 40 m (44 yards) up, most are 2–16 m above ground. Presence of mistletoe
Mistletoe
Mistletoe is the common name for obligate hemi-parasitic plants in several families in the order Santalales. The plants in question grow attached to and within the branches of a tree or shrub.-Mistletoe in the genus Viscum:...
s or vine
Vine
A vine in the narrowest sense is the grapevine , but more generally it can refer to any plant with a growth habit of trailing or scandent, that is to say climbing, stems or runners...
s like Common Ivy (Hedera helix) on side branches near the trunk (where nests are preferentially built) will make a tree markedly more attractive. Fieldfare
Fieldfare
The Fieldfare is a member of the thrush family Turdidae. It breeds in woodland and scrub in northern Europe and Asia. It is strongly migratory, with many northern birds moving south during the winter. It is a very rare breeder in Great Britain and Ireland, but winters in large numbers in these...
s (Turdus pilaris) nesting in the vicinity will also increase the desirability of nest sites to Great Grey Shrikes, which moreover often refuse to prey upon these thrush
Thrush (bird)
The thrushes, family Turdidae, are a group of passerine birds that occur worldwide.-Characteristics:Thrushes are plump, soft-plumaged, small to medium-sized birds, inhabiting wooded areas, and often feed on the ground or eat small fruit. The smallest thrush may be the Forest Rock-thrush, at and...
es' nestlings though the opportunity is there. Apparently, the two species are more efficient in spotting potential nest predators – in particular corvids – early on and mobbing them off cooperatively than either is on its own. Otherwise, there is no clear preference for particular taxa of nesting trees, provided they are sufficiently dense. Conifers seem to have become more popular with European L. excubitor in recent decades, but a diversity of deciduous trees is used just as well. Far more rarely, large and especially thorn
Thorns, spines, and prickles
In botanical morphology, thorns, spines, and prickles are hard structures with sharp, or at least pointed, ends. In spite of this common feature, they differ in their growth and development on the plant; they are modified versions of different plant organs, stems, stipules, leaf veins, or hairs...
y shrubs are used for nesting. The actual nesting site is chosen by the male; the courtship visits of the female are mainly to form and strengthen the pair bond. Also, though the partners build the nest together, the male collects most of the nesting material. The cup nest is quite sizable, measuring 20–28 cm (8–11 in) in outer diameter. Its body is constructed of coarse vegetable material – mainly large twigs and chunks of moss
Moss
Mosses are small, soft plants that are typically 1–10 cm tall, though some species are much larger. They commonly grow close together in clumps or mats in damp or shady locations. They do not have flowers or seeds, and their simple leaves cover the thin wiry stems...
, though bits of fabric and rubbish may be added. The interior cup is 8–12 cm (3-4.7 in) in diameter and 10–15 cm (4–6 in) deep; it is lined with fine twigs and roots, lichen
Lichen
Lichens are composite organisms consisting of a symbiotic organism composed of a fungus with a photosynthetic partner , usually either a green alga or cyanobacterium...
, hair and feathers. Building a nest from scratch takes a pair one to two weeks, but if nests of the previous year in good locations remain usable, they are repaired rather than discarded.
Avian incubation
Incubation refers to the process by which certain oviparous animals hatch their eggs, and to the development of the embryo within the egg. The most vital factor of incubation is the constant temperature required for its development over a specific period. Especially in domestic fowl, the act of...
takes around 16 days but may be closer to three weeks for large clutches; it is generally done only by the female. While the male may briefly take over incubating, his task during this time is to provide food. The altricial
Altricial
Altricial, meaning "requiring nourishment", refers to a pattern of growth and development in organisms which are incapable of moving around on their own soon after hatching or being born...
nestlings hatch naked, blind and pink-skinned, weighing c.4 g (0.141095848420448 oz); their skin turns darker after a few days. The inside of their beak is pink and they probably lack spots or other prominent marks; the wattles at the corners of the mouth are yellow as in many passerine
Passerine
A passerine is a bird of the order Passeriformes, which includes more than half of all bird species. Sometimes known as perching birds or, less accurately, as songbirds, the passerines form one of the most diverse terrestrial vertebrate orders: with over 5,000 identified species, it has roughly...
s. As the nestlings grow, the female broods them, and later on assists in providing food. The young fledge
Fledge
Fledge is the stage in a young bird's life when the feathers and wing muscles are sufficiently developed for flight. It also describes the act of a chick's parents raising it to a fully grown state...
after 2–3 weeks, typically in late June or early July; they become independent of their parents about 3–6 weeks later. Sometimes, a parent will single out particular fledglings (possibly the weakest ones) and focus their care and feeding on these during this time. Other adults have occasionally been recorded assisting in feeding a pair's offspring; it is not clear whether these helpers at the nest
Helpers at the nest
Helpers at the nest is a term used in behavioural ecology and evolutionary biology to describe a social structure in which juveniles and sexually mature adolescents of either one or both sexes, remain in association with their parents and help them raise subsequent broods or litters, instead of...
are offspring of previous years, or unrelated non-breeding "floaters" or breeding neighbors.
Common Cuckoo
Common Cuckoo
The Common Cuckoo is a member of the cuckoo order of birds, Cuculiformes, which includes the roadrunners, the anis and the coucals....
s (Cuculus canorus) have been noted as regular brood parasite
Brood parasite
Brood parasites are organisms that use the strategy of brood parasitism, a kind of kleptoparasitism found among birds, fish or insects, involving the manipulation and use of host individuals either of the same or different species to raise the young of the brood-parasite...
s of L. e. excubitor in the past; for reasons unknown this has ceased since the late 1970s or so. It may well be that the cuckoo's gens
Gens (behaviour)
In animal behaviour, a gens or host race is a host-specific lineage of a brood parasite species. Brood parasites such as cuckoos, which use multiple host species to raise their chicks, evolve different gentes, each one specific to its host species...
laying eggs similar to those of the Great Grey Shrike has become extinct. Among predators of eggs and nestlings, corvids (Corvidae) – extremely close relatives of the shrikes (Laniidae) as it happens – are most significant.
Usually more than half of all nests manage to hatch at least one young, and around three-quarters of all eggs laid hatch, suggesting that if eggs are lost before hatching, it usually is the entire clutch. Half to three-quarters of the hatched young successfully fledge under most circumstances. They will become sexually mature in their first spring and often attempt to breed right away. On average, Great Grey Shrikes get a chance at four breeding attempts during their life, with most birds in the wild getting eaten by a large bird of prey
Bird of prey
Birds of prey are birds that hunt for food primarily on the wing, using their keen senses, especially vision. They are defined as birds that primarily hunt vertebrates, including other birds. Their talons and beaks tend to be relatively large, powerful and adapted for tearing and/or piercing flesh....
or carnivorous mammal
Mammal
Mammals are members of a class of air-breathing vertebrate animals characterised by the possession of endothermy, hair, three middle ear bones, and mammary glands functional in mothers with young...
or dying of other causes before the end of their fifth winter. The maximum documented lifespan, however, is 12 years.
Conservation status
As remarked above, the Great Grey Shrike has apparently become extinct as a breeding bird in Switzerland and the Czech RepublicCzech Republic
The Czech Republic is a landlocked country in Central Europe. The country is bordered by Poland to the northeast, Slovakia to the east, Austria to the south, and Germany to the west and northwest....
. Overall, its stocks seem to be declining in the European part of its range since the 1970s. In North America, the populations seem to have been stable by contrast, except in the east. The roughly 11-year sunspot cycle does not seem to be closely linked to these fluctuations, and probably neither to the eight-year cycle recorded in subspecies
Subspecies
Subspecies in biological classification, is either a taxonomic rank subordinate to species, ora taxonomic unit in that rank . A subspecies cannot be recognized in isolation: a species will either be recognized as having no subspecies at all or two or more, never just one...
borealis (and perhaps present in others). Rather, the increase and decline seem to be reactions to changing land use, with an increase as the number of agricultural workers declined after World War II and land fell fallow, declining again when land consolidation (see e.g. Flurbereinigung
Flurbereinigung
Flurbereinigung is the German word used to describe land reforms in various countries, especially Germany and Austria. The term can best be translated as land consolidation. Another European country where those land reforms have been carried out is France...
) had seriously depleted the number of hedgerows and similar elevated growth formerly common amidst the agricultural landscape. For such a predatory bird, the indiscriminate use of pesticide
Pesticide
Pesticides are substances or mixture of substances intended for preventing, destroying, repelling or mitigating any pest.A pesticide may be a chemical unicycle, biological agent , antimicrobial, disinfectant or device used against any pest...
s (which will accumulate in adult carnivores and inhibit breeding success) around the 1960s probably had a detrimental influence on stocks too.
Altogether, the Great Grey Shrike is common and widespread and not considered a threatened species
Threatened species
Threatened species are any speciesg animals, plants, fungi, etc.) which are vulnerable to endangerment in the near future.The World Conservation Union is the foremost authority on threatened species, and treats threatened species not as a single category, but as a group of three categories,...
by the IUCN (though they still include L. meridionalis in L. excubitor). Wherever it occurs, its numbers are usually many hundreds or even thousands per country. Its stronghold is the region around Sweden, where at least almost 20,000, perhaps as many as 50,000 were believed to live in the late 20th century. However, in some countries it is not robustly established; in Estonia
Estonia
Estonia , officially the Republic of Estonia , is a state in the Baltic region of Northern Europe. It is bordered to the north by the Gulf of Finland, to the west by the Baltic Sea, to the south by Latvia , and to the east by Lake Peipsi and the Russian Federation . Across the Baltic Sea lies...
only a few hundred are found, with less than 200 in Belgium and some more or less than 100 in Latvia
Latvia
Latvia , officially the Republic of Latvia , is a country in the Baltic region of Northern Europe. It is bordered to the north by Estonia , to the south by Lithuania , to the east by the Russian Federation , to the southeast by Belarus and shares maritime borders to the west with Sweden...
and Lithuania
Lithuania
Lithuania , officially the Republic of Lithuania is a country in Northern Europe, the biggest of the three Baltic states. It is situated along the southeastern shore of the Baltic Sea, whereby to the west lie Sweden and Denmark...
, respectively. The few dozen in the Netherlands and the 10 birds or so in Denmark might disappear because of a few years of adverse circumstances. By contrast, in Luxembourg
Luxembourg
Luxembourg , officially the Grand Duchy of Luxembourg , is a landlocked country in western Europe, bordered by Belgium, France, and Germany. It has two principal regions: the Oesling in the North as part of the Ardennes massif, and the Gutland in the south...
plentiful high-quality habitat is found; though the number of Great Grey Shrikes in this tiny country is necessarily limited, the average population density
Population density
Population density is a measurement of population per unit area or unit volume. It is frequently applied to living organisms, and particularly to humans...
there is 25 times as high as in Lithuania.
External links
- Great Grey Shrike videos, photos & sounds on the Internet Bird Collection
- Northern Shrike stamps (for 7 countries) shows Circum-Polar/Equatorieal Range-Map
- Northern Shrike - Lanius Excubitor - USGS Patuxent Bird Identification InfoCenter
- Northern Shrike Species Account - Cornell Lab of Ornithology
- Northern Shrike Information - South Dakota Birds and Birding
- Oiseaux Pictures