Ruff
Encyclopedia
The Ruff is a medium-sized wading bird
that breeds in marsh
es and wet meadow
s across northern Eurasia
. This highly gregarious sandpiper
is migratory
and sometimes forms huge flocks in its winter grounds, which include southern and western Europe, Africa, southern Asia and Australia. It is usually considered to be the only member of its genus
, and the Broad-billed
and Sharp-tailed Sandpiper
s are its closest relatives.
The Ruff is a long-necked, pot-bellied bird. This species shows marked sexual dimorphism
; the male is much larger than the female (the reeve), and has a breeding plumage
that includes brightly coloured head tufts, bare orange facial skin, extensive black on the breast, and the large collar of ornamental feathers that inspired this bird's English name. The female and the non-breeding male have grey-brown upperparts and mainly white underparts. Three differently plumaged types of male, including a rare form that mimics the female, use a variety of strategies to obtain mating opportunities at a lek, and the colourful head and neck feathers are erected as part of the elaborate main courting display. The female has one brood per year and lays four eggs
in a well-hidden ground nest
, incubating the eggs and rearing the chicks, which are mobile soon after hatching, on her own. Predators of wader chicks and eggs include mammals such as fox
es, feral cat
s and stoat
s, and birds such as large gull
s, corvids
and skua
s.
The Ruff forage
s in wet grassland and soft mud, probing or searching by sight for edible items. It primarily feeds on insects, especially in the breeding season, but it will consume plant material, including rice
and maize, on migration and in winter. Classified as "least concern
" on the IUCN Red List
criteria, the global conservation
concerns are relatively low because of the large numbers that breed in Scandinavia and the Arctic. However, the range in much of Europe is contracting because of land drainage, increased fertiliser use, the loss of mown or grazed breeding sites, and over-hunting. This decline has seen it listed in the Agreement on the Conservation of African-Eurasian Migratory Waterbirds (AEWA).
The Ruff is a wader
in the large family Scolopacidae
, the typical shorebirds. It is the sole member of the genus Philomachus, and recent research suggests that its closest relatives are the Broad-billed Sandpiper Limicola falcinellus and the Sharp-tailed Sandpiper Calidris acuminata. It has no recognised subspecies or geographical variants.
This species was first described by Carl Linnaeus in his Systema Naturae
in 1758 as Tringa pugnax. It was moved into its current genus by German
naturalist
Blasius Merrem
in 1804. Both parts of the binomial name refer to the aggressive behaviour of the bird at its mating arenas; Philomachus is derived from Ancient Greek
philo- "loving" and machē "battle", and pugnax from the Latin
term for "combative".
The original English name for this bird, dating back to at least 1465, is the ree, perhaps derived from a dialectical term meaning "frenzied"; a later name reeve, which is still used for the female, is of unknown origin, but may be derived from the shire-reeve
, a feudal officer, likening the male's flamboyant plumage to the official's robes. The current name was first recorded in 1634, and is derived from the ruff
, an exaggerated collar fashionable from the mid-sixteenth century to the mid-seventeenth century, since the male bird's neck ornamental feathers resemble the neck-wear.
appearance, with a small head, medium-length bill, longish neck and pot-bellied body. It has long legs that are variable in colour but usually yellow or orange. In flight, it has a deeper, slower wing stroke than other waders of a similar size, and displays a thin, indistinct white bar on the wing, and white ovals on the sides of the tail .
This species shows sexual dimorphism
. Although a small percentage of males resemble females, the typical male is much larger than the female and has an elaborate breeding plumage. He is 29–32 cm (11.4–12.6 in) long with a 54–60 cm (21.25–23.6 in) wingspan, and weighs about 180 g (6.4 oz). In the May-to-June breeding season, the typical male's legs, bill and warty bare facial skin are orange, and he has distinctive head tufts and a neck ruff. These ornaments vary on individual birds, being black, chestnut or white, with the colouring solid, barred or irregular. The grey-brown back has a scale-like pattern, often with black or chestnut feathers, and the underparts are white with extensive black on the breast. The extreme variability of the main breeding plumage is thought to have developed to aid individual recognition in a species that has communal breeding displays, but is usually mute.
Outside the breeding season, the typical male's head and neck decorations and the bare facial skin are lost and the legs and bill become duller. The upperparts are grey-brown, and the underparts are white with grey mottling on the breast and flanks.
The female, or "reeve", is 22–26 cm (8.7–10.2 in) long with a 46–49 cm (18.1–19.32 in) wingspan, and weighs about 110 g (3.9 oz). In breeding plumage, she has grey-brown upperparts with white-fringed, dark-centred feathers. The breast and flanks are variably blotched with black. In winter, her plumage is similar to that of the male, but the sexes are distinguishable on size. The plumage of the juvenile Ruff resembles the non-breeding adult, but has upperparts with a neat, scale-like pattern with dark feather centres, and a strong buff tinge to the underparts.
Typical adult male Ruffs start to moult
into the main display plumage before their return to the breeding areas, and the proportion of birds with head and neck decorations gradually increases through the spring. Second-year birds lag behind full adults in developing breeding plumage. They have a lower body mass and a slower weight increase than full adults, and perhaps the demands made on their energy reserves during the migration flight are the main reason of the delayed moult.
Ruffs of both sexes have an additional moult stage between the winter and final summer plumages, a phenomenon also seen in the Bar-tailed Godwit
. Before developing the full display finery with coloured ruff and tufts, the males replace part of their winter plumage with striped feathers. Females also develop a mix of winter and striped feathers before reaching their summer appearance. The final male breeding plumage results from the replacement of both winter and striped feathers, but the female retains the striped feathers and replaces only the winter feathers to reach her summer plumage. The striped prenuptial plumages may represent the original breeding appearance of this species, the male's showy nuptial feathers evolving later under strong sexual selection
pressures.
Adult males and most adult females start their pre-winter moult before returning south, but complete most feather replacement on the wintering grounds. In Kenya
, males moult 3–4 weeks ahead of the females, finishing before December, whereas females typically complete feather replacement during December and early January. Juveniles moult from their first summer body plumage into winter plumage during late September to November, and later undergo a pre-breeding moult similar in timing and duration to that of the adults, and often producing as brightly coloured an appearance.
Two other waders can be confused with the Ruff. The juvenile Sharp-tailed Sandpiper
is a little smaller than a juvenile female Ruff and has a similar rich orange-buff breast, but the Ruff is slimmer with a longer neck and legs, a rounder head, and a much plainer face. The Buff-breasted Sandpiper
also resembles a small juvenile Ruff, but even the female Ruff is noticeably larger than the sandpiper, with a longer bill, more rotund body and scaly-patterned upperparts.
The Ruff is a migratory species, breeding in wetlands in colder regions of northern Eurasia, and spends the northern winter in the tropics
, mainly in Africa. Some Siberian breeders undertake an annual round trip of up to 30,000 km (18,500 mi) to the West African wintering grounds. There is a limited overlap of the summer and winter ranges in western Europe. The Ruff breeds in extensive lowland freshwater marshes and damp grasslands. It avoids barren tundra
and areas badly affected by severe weather, preferring hummocky marshes and deltas with shallow water. The wetter areas provide a source of food, the mounds and slopes may be used for leks, and dry areas with sedge
or low scrub offer nesting sites. A Hungarian study showed that moderately intensive grazing of grassland, with more than one cow per hectare (2.5 acres), was found to attract more nesting pairs. When not breeding, the birds use a wider range of shallow wetlands, such as irrigated fields
, lake margins, and mining subsidence
and other floodlands. Dry grassland, tidal mudflats and the seashore are less frequently used. The density can reach 129 individuals per square kilometre (334 per square mile), but is usually much lower.
The Ruff breeds in Europe and Asia from Scandinavia and Great Britain almost to the Pacific. In Europe it is found in cool temperate areas, but over its Russian range it is an Arctic species, occurring mainly north of about 65°N. The largest numbers breed in Russia (more than 1 million pairs), Sweden (61,000 pairs), Finland (39,000 pairs) and Norway (14,000 pairs). Although it also breeds from Britain east through the Low Countries to Poland, Germany and Denmark, there are fewer than 2,000 pairs in these more southerly areas.
_w_img_6570.jpg)
It is highly gregarious on migration, travelling in large flocks that can contain hundreds or thousands of individuals. Huge dense groups form on the wintering grounds; one flock in Senegal
contained a million birds. A minority winter further east to Burma, south China, New Guinea and scattered parts of southern Australia, or on the Atlantic and Mediterranean coasts of Europe. In Great Britain and parts of coastal western Europe, where the breeding and wintering ranges overlap, birds may be present throughout the year. Non-breeding birds may also remain year round in the tropical wintering quarters. The Ruff is an uncommon visitor to Alaska (where it has occasionally bred), Canada and the contiguous states of the US, and has wandered to Iceland, Central America, northern South America, Madagascar and New Zealand. It has been recorded as breeding well south of its main range in northern Kazakhstan
, a major migration stopover area.
The male, which plays no part in nesting or chick care, leaves the breeding grounds in late June or early July, followed later in July by the female and juveniles. Males typically make shorter flights and winter further north than females; for example, virtually all wintering Ruffs in Britain are males, whereas in Kenya most are females. Many migratory species use this differential wintering strategy, since it reduces feeding competition between the sexes and enables territorial males to reach the breeding grounds as early as possible, improving their chances of successful mating. Male Ruffs may also be able to tolerate colder winter conditions because they are larger than females.
Birds returning north in spring across the central Mediterranean appear to follow a well-defined route. Large concentrations of Ruffs form every year at particular stopover
sites to feed, and individuals marked with rings
or dye reappear in subsequent years. The refuelling sites are closer together than the theoretical maximum travel distance calculated from the mean body mass, and provide evidence of a migration strategy using favoured intermediate sites. The Ruff stores fat as a fuel, but unlike mammals, uses lipid
s as the main energy source for exercise (including migration) and, when necessary, keeps warm by shivering; however, little research has been conducted on the mechanisms by which they oxidise lipids.
Males display during the breeding season at a lek in a traditional open grassy arena. The Ruff is one of the few lekking species in which the display is primarily directed at other males rather than to the females, and it is among the small percentage of birds in which the males have well-marked and inherited
variations in plumage and mating behaviour. There are three male forms: the typical territorial males, satellite males which have a white neck ruff, and a very rare, recently discovered variant with female-like plumage. The territorial males, about 84% of the total, have strongly coloured black or chestnut ruffs and stake out and occupy small mating territories in the lek. They actively court females and display a high degree of aggression towards other resident males; 5–20 territorial males each hold an area of the lek about 1 m (1 yd) across, usually with bare soil in the centre. They perform an elaborate display that includes wing fluttering, jumping, standing upright, crouching with ruff erect, or lunging at rivals. They are typically silent even when displaying, although a soft gue-gue-gue may occasionally be given.
Territorial
males are very site-faithful; 90% return to the same lekking sites in subsequent seasons, the most dominant males being the most likely to reappear. Site-faithful males can acquire accurate information about the competitive abilities of other males, leading to well-developed dominance relationships. Such stable relationships reduce conflict and the risk of injury, and the consequent lower levels of male aggression are less likely to scare off females. Lower-ranked territorial males also benefit from site fidelity since they can remain on the leks while waiting for the top males eventually to drop out.
Satellite males, about 16% of the total number, have white or mottled ruffs and do not occupy territories; they enter leks and attempt to mate with the females visiting the territories occupied by the resident males. Resident males tolerate the satellite birds because, although they are competitors for mating with the females, the presence of both types of male on a territory attracts additional females. Females also prefer larger leks, and leks surrounded by taller plants, which give better nesting habitat.
The behaviour and appearance for an individual male remain constant through its adult life, and are determined by a simple genetic polymorphism
. It was originally thought that the difference between the two types of males was due to a sex-linked genetic factor, but in fact the genetic locus
relevant for the mating strategy is located on an autosome
, or non-sex chromosome
. That means that both sexes can carry the two different forms of the gene, not just males. The non-territorial female does not normally show evidence of its genetic type, but when females are given testosterone
implants, they display the male territorial behaviour corresponding to their genotype
. Territorial plumage and behaviour are inherited as recessive characteristics.
Although satellite males are on average slightly smaller and lighter than residents, the nutrition of the chicks does not, as previously thought, influence mating strategy; rather, the inherited mating strategy influences body size. Resident-type chicks will, if provided with the same amount of food, grow heavier than satellite-type chicks. Satellite males do not have to expend energy to defend a territory, and can spend more time foraging, so they do not need to be as bulky as the residents; indeed, since they fly more, there would be a physiological cost to additional weight.
A third type of male was first described in 2006; this is a permanent female mimic, the first such reported for a bird. About 1% of males are small, intermediate in size between males and females, and do not grow the elaborate breeding plumage of the territorial and satellite males, although they have much larger internal testes
than the ruffed males. This cryptic male, or "faeder" (Old English "father") obtains access to mating territories together with the females, and "steals" matings when the females crouch to solicit copulation. The faeder moults into the prenuptial male plumage with striped feathers, but does not go on to develop the ornamental feathers of the normal male. As described above, this stage is thought to show the original male breeding plumage, before other male types evolved. A faeder can be distinguished in the hand by its wing length, which is intermediate between those of displaying males and females. Despite their feminine appearance, the faeders migrate with the larger 'normal' lekking males and spend the winter with them.
The faeders are sometimes mounted by independent or satellite males, but are as often "on top" in homosexual mountings as the ruffed males, suggesting that their true identity is known by the other males. Females never mount males. Preliminary research results suggest that the faeder characteristics are genetically controlled by a single dominant gene. Females often seem to prefer mating with faeders to copulation with normal males, and normal males also copulate with faeders (and vice versa) relatively more often than with females. The homosexual copulations may attract females to the lek, like the presence of satellite males.
Not all mating takes place at the lek, since only a minority of the males attend an active lek. As alternative strategies, males can also directly pursue females ("following") or wait for them as they approached good feeding sites ("intercepting"). Males switched between the three tactics, being more likely to attend a lek when the copulation rate the previous day was high or when fewer females were available after nesting had started. Lekking rates were low in cold weather early in the season when off-lek males spent most of their time feeding.
The level of polyandry
in the Ruff is the highest known for any avian lekking species and for any shorebird. More than half of female Ruffs mate with, and have clutches fertilised by, more than one male, and individual females mate with males of both main behavioural morphs more often than expected by chance. In lekking species, females can choose mates without risking the loss of support from males in nesting and rearing chicks, since the males take no part in raising the brood anyway. In the absence of this cost, if polyandry is advantageous, it would be expected to occur at a higher rate in lekking than among pair-bonded species.
The nest is a shallow ground scrape lined with grass leaves and stems, and concealed in marsh plants or tall grass up to 400 m (400 yd) from the lek. Nesting is solitary, although several females may lay in the general vicinity of a lek. The eggs are slightly glossy, green or olive, and marked with dark blotches; they are laid from mid-March to early June depending on latitude.
The typical clutch is four eggs, each egg measuring 44 x 31 mm (1.7 x 1.2 in) in size and weighing 21.0 g (0.75 oz) of which 5% is shell. Incubation is by the female alone, and the time to hatching is 20–23 days, with a further 25–28 days to fledging. The precocial
chicks have buff and chestnut down, streaked and barred with black, and frosted with white; they feed themselves on a variety of small invertebrates, but are brooded by the female. One brood is raised each year.
Predators of waders breeding in wet grasslands include birds such as large gulls, Common Raven
, Carrion
and Hooded Crow
s, and Great
and Arctic Skua
s; foxes occasionally take waders, and the impact of feral cats and stoats is unknown. Overgrazing can increase predation by making nests easier to find. In captivity, the main causes of chick mortality were stress-related sudden death and twisted neck syndrome
. Adults seem to show little evidence of external parasites
, but may have significant levels of disease on their tropical wintering grounds, including avian malaria
in their inland freshwater habitats, and so they might be expected to invest strongly in their immune system
s; however, a 2006 study that analysed the blood of migrating Ruffs intercepted in Friesland
showed that this bird actually has unexplained low levels of immune responses on at least one measure of resistance. The Ruff can breed from its second year, and the average lifespan
for birds that have passed the chick stage is about 4.4 years, although a Finnish bird lived to a record 13 years and 11 months.
, picking items off the surface. It will feed at night as well as during the day. When feeding, the Ruff frequently raises its back feathers, producing a loose pointed peak on the back; this habit is shared only by the Black-tailed Godwit.
During the breeding season, the Ruff’s diet consists almost exclusively of the adults and larva of terrestrial and aquatic insects such as beetles and flies. On migration and during the winter, the Ruff eats insects (including caddis flies
, water-beetles, mayflies
and grasshoppers), crustaceans, spiders, molluscs, worms, frogs, small fish, and also the seeds of rice and other cereals, sedges, grasses and aquatic plants. Migrating birds in Italy varied their diet according to what was available at each stopover site. Green aquatic plant material, spilt rice and maize, flies and beetles were found, along with varying amounts of grit. On the main wintering grounds in West Africa, rice is a favoured food during the later part of the season as the ricefields dry out.
Just before migration, the Ruff increases its body mass at a rate of about 1% a day, much slower than the Bar-tailed Godwits breeding in Alaska, which fatten at four times that rate. This is thought to be because the godwit cannot use refuelling areas to feed on its trans-Pacific flight, whereas the Ruff is able to make regular stops and take in food during overland migration. For the same reason, the Ruff does not physiologically shrink its digestive organs to reduce bodyweight before migrating, unlike the godwit.
Ruffs were formerly trapped for food in England in large numbers; on one occasion, 2,400 were served at Archbishop Neville's enthronement banquet in 1465. The birds were netted while lekking, sometimes being fattened with bread, milk and seed in holding pens before preparation for the table.
The heavy toll on breeding birds, together with loss of habitat through drainage and collection by nineteenth-century trophy hunters and egg collectors, meant that the species became almost extinct in England by the 1880s, although recolonisation in small numbers has occurred since 1963. The draining of wetlands from the 1800s onwards in southern Sweden has resulted in the Ruff's disappearance from many areas there, although it remains common in the north of the country. The use of insecticide
s and draining of wetlands has led to a decrease in the number of Ruff in Denmark since the early 1900s. There are still areas where the Ruff and other wetland birds are hunted legally or otherwise for food. A large-scale example is the capture of more than one million waterbirds (including Ruffs) in a single year from Lake Chilwa
in Malawi
.
Although this bird eats rice on the wintering grounds, where it can make up nearly 40% of its diet, it takes mainly waste and residues from cropping and threshing, not harvestable grain. It has sometimes been viewed as a pest, but the deeper water and presence of invertebrate prey in the economically important early winter period means that the wader has little effect on crop yield.
(that is, declining more than 30 percent in ten years or three generations). For these reasons, the Ruff is classified as "least concern
".
_near_hodal_w_img_6534.jpg)
The most important breeding populations in Europe, in Russia and Sweden are stable, and the breeding range in Norway has expanded to the south, but populations have more than halved in Finland, Poland, Latvia and The Netherlands. Although the small populations in these countries are of limited overall significance, the decline is a continuation of trend towards range contraction that has occurred over the last two centuries. The drop in numbers in Europe has been attributed to drainage, increased fertiliser use, the loss of formerly mown or grazed breeding sites and over-hunting.
Fossils from the Pleistocene
suggest that this species bred further south in Europe in the cool periods between glaciations than it does now. Its sensitivity to changing climate as well as to water table levels and the speed of vegetation growth has led to suggestions that its range is affected by global warming, and the Ruff might act as an indicator species for monitoring climate change. Potential threats to this species may also include outbreaks of diseases to which it is susceptible such as influenza, botulism
and avian malaria
.
The Ruff is one of the species to which the Agreement on the Conservation of African-Eurasian Migratory Waterbirds (AEWA) applies, where it is allocated to category 2c; that is, the populations in need of special attention as they are showing "significant long-term decline" in much of its range. This commits signatories to regulate the taking of listed species or their eggs, to establish protected areas to conserve habitats for the listed species, to regulate hunting and to monitor the populations of the birds concerned.
Wader
Waders, called shorebirds in North America , are members of the order Charadriiformes, excluding the more marine web-footed seabird groups. The latter are the skuas , gulls , terns , skimmers , and auks...
that breeds in marsh
Marsh
In geography, a marsh, or morass, is a type of wetland that is subject to frequent or continuous flood. Typically the water is shallow and features grasses, rushes, reeds, typhas, sedges, other herbaceous plants, and moss....
es and wet meadow
Meadow
A meadow is a field vegetated primarily by grass and other non-woody plants . The term is from Old English mædwe. In agriculture a meadow is grassland which is not grazed by domestic livestock but rather allowed to grow unchecked in order to make hay...
s across northern Eurasia
Eurasia
Eurasia is a continent or supercontinent comprising the traditional continents of Europe and Asia ; covering about 52,990,000 km2 or about 10.6% of the Earth's surface located primarily in the eastern and northern hemispheres...
. This highly gregarious sandpiper
Scolopacidae
The sandpipers are a large family, Scolopacidae, of waders or shorebirds. They include many species called sandpipers, as well as those called by names such as curlew and snipe. The majority of these species eat small invertebrates picked out of the mud or soil...
is migratory
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...
and sometimes forms huge flocks in its winter grounds, which include southern and western Europe, Africa, southern Asia and Australia. It is usually considered to be the only member of its genus
Genus
In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...
, and the Broad-billed
Broad-billed Sandpiper
The Broad-billed Sandpiper is a small wading bird. It is the only member of the genus Limicola; some have proposed that it should be placed in the genus Erolia with the "stint" sandpipers, but more recent research suggests that it is should rather go into the genus Philomachus with the ruff and...
and Sharp-tailed Sandpiper
Sharp-tailed Sandpiper
The Sharp-tailed Sandpiper, Calidris acuminata is a small wader.- Taxonomy :More recently, a review of new data has indicated that this bird should perhaps better be placed into the genus Philomachus- as P...
s are its closest relatives.
The Ruff is a long-necked, pot-bellied bird. This species shows marked sexual dimorphism
Sexual dimorphism
Sexual dimorphism is a phenotypic difference between males and females of the same species. Examples of such differences include differences in morphology, ornamentation, and behavior.-Examples:-Ornamentation / coloration:...
; the male is much larger than the female (the reeve), and has a breeding 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...
that includes brightly coloured head tufts, bare orange facial skin, extensive black on the breast, and the large collar of ornamental feathers that inspired this bird's English name. The female and the non-breeding male have grey-brown upperparts and mainly white underparts. Three differently plumaged types of male, including a rare form that mimics the female, use a variety of strategies to obtain mating opportunities at a lek, and the colourful head and neck feathers are erected as part of the elaborate main courting display. The female has one brood per year and lays four eggs
Bird egg
Bird eggs are laid by females and incubated for a time that varies according to the species; a single young hatches from each egg. Average clutch sizes range from one to about 17...
in a well-hidden ground nest
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...
, incubating the eggs and rearing the chicks, which are mobile soon after hatching, on her own. Predators of wader chicks and eggs include mammals such as fox
Fox
Fox is a common name for many species of omnivorous mammals belonging to the Canidae family. Foxes are small to medium-sized canids , characterized by possessing a long narrow snout, and a bushy tail .Members of about 37 species are referred to as foxes, of which only 12 species actually belong to...
es, feral cat
Feral cat
A feral cat is a descendant of a domesticated cat that has returned to the wild. It is distinguished from a stray cat, which is a pet cat that has been lost or abandoned, while feral cats are born in the wild; the offspring of a stray cat can be considered feral if born in the wild.In many parts of...
s and stoat
Stoat
The stoat , also known as the ermine or short-tailed weasel, is a species of Mustelid native to Eurasia and North America, distinguished from the least weasel by its larger size and longer tail with a prominent black tip...
s, and birds such as large gull
Gull
Gulls are birds in the family Laridae. They are most closely related to the terns and only distantly related to auks, skimmers, and more distantly to the waders...
s, corvids
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...
and skua
Skua
The skuas are a group of seabirds with about seven species forming the family Stercorariidae and the genus Stercorarius. The three smaller skuas are called jaegers in North America....
s.
The Ruff forage
Forage
Forage is plant material eaten by grazing livestock.Historically the term forage has meant only plants eaten by the animals directly as pasture, crop residue, or immature cereal crops, but it is also used more loosely to include similar plants cut for fodder and carried to the animals, especially...
s in wet grassland and soft mud, probing or searching by sight for edible items. It primarily feeds on insects, especially in the breeding season, but it will consume plant material, including rice
Rice
Rice is the seed of the monocot plants Oryza sativa or Oryza glaberrima . As a cereal grain, it is the most important staple food for a large part of the world's human population, especially in East Asia, Southeast Asia, South Asia, the Middle East, and the West Indies...
and maize, on migration and in winter. Classified as "least concern
Least Concern
Least Concern is an IUCN category assigned to extant taxon or lower taxa which have been evaluated but do not qualify for any other category. As such they do not qualify as threatened, Near Threatened, or Conservation Dependent...
" on the IUCN Red List
IUCN Red List
The IUCN Red List of Threatened Species , founded in 1963, is the world's most comprehensive inventory of the global conservation status of biological species. The International Union for Conservation of Nature is the world's main authority on the conservation status of species...
criteria, the global conservation
Bird conservation
Bird conservation is a field in the science of conservation biology related to threatened birds. Humans have had a profound effect on many bird species...
concerns are relatively low because of the large numbers that breed in Scandinavia and the Arctic. However, the range in much of Europe is contracting because of land drainage, increased fertiliser use, the loss of mown or grazed breeding sites, and over-hunting. This decline has seen it listed in the Agreement on the Conservation of African-Eurasian Migratory Waterbirds (AEWA).
Taxonomy and nomenclature
Wader
Waders, called shorebirds in North America , are members of the order Charadriiformes, excluding the more marine web-footed seabird groups. The latter are the skuas , gulls , terns , skimmers , and auks...
in the large family Scolopacidae
Scolopacidae
The sandpipers are a large family, Scolopacidae, of waders or shorebirds. They include many species called sandpipers, as well as those called by names such as curlew and snipe. The majority of these species eat small invertebrates picked out of the mud or soil...
, the typical shorebirds. It is the sole member of the genus Philomachus, and recent research suggests that its closest relatives are the Broad-billed Sandpiper Limicola falcinellus and the Sharp-tailed Sandpiper Calidris acuminata. It has no recognised subspecies or geographical variants.
This species was first described by Carl Linnaeus in his 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...
in 1758 as Tringa pugnax. It was moved into its current genus by German
Germany
Germany , officially the Federal Republic of Germany , is a federal parliamentary republic in Europe. The country consists of 16 states while the capital and largest city is Berlin. Germany covers an area of 357,021 km2 and has a largely temperate seasonal climate...
naturalist
Natural history
Natural history is the scientific research of plants or animals, leaning more towards observational rather than experimental methods of study, and encompasses more research published in magazines than in academic journals. Grouped among the natural sciences, natural history is the systematic study...
Blasius Merrem
Blasius Merrem
Blasius Merrem was a German naturalist.Merrem was born at Bremen, and studied at the university of Göttingen under Johann Friedrich Blumenbach. He developed an interest in zoology, particularly ornithology...
in 1804. Both parts of the binomial name refer to the aggressive behaviour of the bird at its mating arenas; Philomachus is derived from Ancient Greek
Ancient Greek
Ancient Greek is the stage of the Greek language in the periods spanning the times c. 9th–6th centuries BC, , c. 5th–4th centuries BC , and the c. 3rd century BC – 6th century AD of ancient Greece and the ancient world; being predated in the 2nd millennium BC by Mycenaean Greek...
philo- "loving" and machē "battle", and pugnax from the Latin
Latin
Latin is an Italic language originally spoken in Latium and Ancient Rome. It, along with most European languages, is a descendant of the ancient Proto-Indo-European language. Although it is considered a dead language, a number of scholars and members of the Christian clergy speak it fluently, and...
term for "combative".
The original English name for this bird, dating back to at least 1465, is the ree, perhaps derived from a dialectical term meaning "frenzied"; a later name reeve, which is still used for the female, is of unknown origin, but may be derived from the shire-reeve
Sheriff
A sheriff is in principle a legal official with responsibility for a county. In practice, the specific combination of legal, political, and ceremonial duties of a sheriff varies greatly from country to country....
, a feudal officer, likening the male's flamboyant plumage to the official's robes. The current name was first recorded in 1634, and is derived from the ruff
Ruff (clothing)
A ruff is an item of clothing worn in Western Europe from the mid-sixteenth century to the mid-seventeenth century.The ruff, which was worn by men, women and children, evolved from the small fabric ruffle at the drawstring neck of the shirt or chemise...
, an exaggerated collar fashionable from the mid-sixteenth century to the mid-seventeenth century, since the male bird's neck ornamental feathers resemble the neck-wear.
Description
The Ruff has a distinctive gravy boatSauce boat
A sauce boat, gravy boat or saucière is a boat-shaped pitcher in which sauce or gravy is served. It often sits on a matching plate, sometimes attached to the pitcher, to catch dripping sauce....
appearance, with a small head, medium-length bill, longish neck and pot-bellied body. It has long legs that are variable in colour but usually yellow or orange. In flight, it has a deeper, slower wing stroke than other waders of a similar size, and displays a thin, indistinct white bar on the wing, and white ovals on the sides of the tail .
This species shows sexual dimorphism
Sexual dimorphism
Sexual dimorphism is a phenotypic difference between males and females of the same species. Examples of such differences include differences in morphology, ornamentation, and behavior.-Examples:-Ornamentation / coloration:...
. Although a small percentage of males resemble females, the typical male is much larger than the female and has an elaborate breeding plumage. He is 29–32 cm (11.4–12.6 in) long with a 54–60 cm (21.25–23.6 in) wingspan, and weighs about 180 g (6.4 oz). In the May-to-June breeding season, the typical male's legs, bill and warty bare facial skin are orange, and he has distinctive head tufts and a neck ruff. These ornaments vary on individual birds, being black, chestnut or white, with the colouring solid, barred or irregular. The grey-brown back has a scale-like pattern, often with black or chestnut feathers, and the underparts are white with extensive black on the breast. The extreme variability of the main breeding plumage is thought to have developed to aid individual recognition in a species that has communal breeding displays, but is usually mute.
Outside the breeding season, the typical male's head and neck decorations and the bare facial skin are lost and the legs and bill become duller. The upperparts are grey-brown, and the underparts are white with grey mottling on the breast and flanks.
Typical adult male Ruffs start to 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 the main display plumage before their return to the breeding areas, and the proportion of birds with head and neck decorations gradually increases through the spring. Second-year birds lag behind full adults in developing breeding plumage. They have a lower body mass and a slower weight increase than full adults, and perhaps the demands made on their energy reserves during the migration flight are the main reason of the delayed moult.
Ruffs of both sexes have an additional moult stage between the winter and final summer plumages, a phenomenon also seen in the Bar-tailed Godwit
Bar-tailed Godwit
The Bar-tailed Godwit is a large wader in the family Scolopacidae, which breeds on Arctic coasts and tundra mainly in the Old World, and winters on coasts in temperate and tropical regions of the Old World...
. Before developing the full display finery with coloured ruff and tufts, the males replace part of their winter plumage with striped feathers. Females also develop a mix of winter and striped feathers before reaching their summer appearance. The final male breeding plumage results from the replacement of both winter and striped feathers, but the female retains the striped feathers and replaces only the winter feathers to reach her summer plumage. The striped prenuptial plumages may represent the original breeding appearance of this species, the male's showy nuptial feathers evolving later under strong sexual selection
Sexual selection
Sexual selection, a concept introduced by Charles Darwin in his 1859 book On the Origin of Species, is a significant element of his theory of natural selection...
pressures.
Adult males and most adult females start their pre-winter moult before returning south, but complete most feather replacement on the wintering grounds. In Kenya
Kenya
Kenya , officially known as the Republic of Kenya, is a country in East Africa that lies on the equator, with the Indian Ocean to its south-east...
, males moult 3–4 weeks ahead of the females, finishing before December, whereas females typically complete feather replacement during December and early January. Juveniles moult from their first summer body plumage into winter plumage during late September to November, and later undergo a pre-breeding moult similar in timing and duration to that of the adults, and often producing as brightly coloured an appearance.
Two other waders can be confused with the Ruff. The juvenile Sharp-tailed Sandpiper
Sharp-tailed Sandpiper
The Sharp-tailed Sandpiper, Calidris acuminata is a small wader.- Taxonomy :More recently, a review of new data has indicated that this bird should perhaps better be placed into the genus Philomachus- as P...
is a little smaller than a juvenile female Ruff and has a similar rich orange-buff breast, but the Ruff is slimmer with a longer neck and legs, a rounder head, and a much plainer face. The Buff-breasted Sandpiper
Buff-breasted Sandpiper
The Buff-breasted Sandpiper, Tryngites subruficollis, is a small shorebird. It is a calidrid sandpipers and currently considered to be the only member of the genus Tryngites. Indeed, it probably belongs in the genus Calidris itself, or more precisely with the small species thereof which should be...
also resembles a small juvenile Ruff, but even the female Ruff is noticeably larger than the sandpiper, with a longer bill, more rotund body and scaly-patterned upperparts.
Distribution and habitat
Tropics
The tropics is a region of the Earth surrounding the Equator. It is limited in latitude by the Tropic of Cancer in the northern hemisphere at approximately N and the Tropic of Capricorn in the southern hemisphere at S; these latitudes correspond to the axial tilt of the Earth...
, mainly in Africa. Some Siberian breeders undertake an annual round trip of up to 30,000 km (18,500 mi) to the West African wintering grounds. There is a limited overlap of the summer and winter ranges in western Europe. The Ruff breeds in extensive lowland freshwater marshes and damp grasslands. It avoids barren 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...
and areas badly affected by severe weather, preferring hummocky marshes and deltas with shallow water. The wetter areas provide a source of food, the mounds and slopes may be used for leks, and dry areas with sedge
Cyperaceae
Cyperaceae are a family of monocotyledonous graminoid flowering plants known as sedges, which superficially resemble grasses or rushes. The family is large, with some 5,500 species described in about 109 genera. These species are widely distributed, with the centers of diversity for the group...
or low scrub offer nesting sites. A Hungarian study showed that moderately intensive grazing of grassland, with more than one cow per hectare (2.5 acres), was found to attract more nesting pairs. When not breeding, the birds use a wider range of shallow wetlands, such as irrigated fields
Irrigation
Irrigation may be defined as the science of artificial application of water to the land or soil. It is used to assist in the growing of agricultural crops, maintenance of landscapes, and revegetation of disturbed soils in dry areas and during periods of inadequate rainfall...
, lake margins, and mining subsidence
Subsidence
Subsidence is the motion of a surface as it shifts downward relative to a datum such as sea-level. The opposite of subsidence is uplift, which results in an increase in elevation...
and other floodlands. Dry grassland, tidal mudflats and the seashore are less frequently used. The density can reach 129 individuals per square kilometre (334 per square mile), but is usually much lower.
The Ruff breeds in Europe and Asia from Scandinavia and Great Britain almost to the Pacific. In Europe it is found in cool temperate areas, but over its Russian range it is an Arctic species, occurring mainly north of about 65°N. The largest numbers breed in Russia (more than 1 million pairs), Sweden (61,000 pairs), Finland (39,000 pairs) and Norway (14,000 pairs). Although it also breeds from Britain east through the Low Countries to Poland, Germany and Denmark, there are fewer than 2,000 pairs in these more southerly areas.
Senegal
Senegal , officially the Republic of Senegal , is a country in western Africa. It owes its name to the Sénégal River that borders it to the east and north...
contained a million birds. A minority winter further east to Burma, south China, New Guinea and scattered parts of southern Australia, or on the Atlantic and Mediterranean coasts of Europe. In Great Britain and parts of coastal western Europe, where the breeding and wintering ranges overlap, birds may be present throughout the year. Non-breeding birds may also remain year round in the tropical wintering quarters. The Ruff is an uncommon visitor to Alaska (where it has occasionally bred), Canada and the contiguous states of the US, and has wandered to Iceland, Central America, northern South America, Madagascar and New Zealand. It has been recorded as breeding well south of its main range in northern Kazakhstan
Kazakhstan
Kazakhstan , 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...
, a major migration stopover area.
The male, which plays no part in nesting or chick care, leaves the breeding grounds in late June or early July, followed later in July by the female and juveniles. Males typically make shorter flights and winter further north than females; for example, virtually all wintering Ruffs in Britain are males, whereas in Kenya most are females. Many migratory species use this differential wintering strategy, since it reduces feeding competition between the sexes and enables territorial males to reach the breeding grounds as early as possible, improving their chances of successful mating. Male Ruffs may also be able to tolerate colder winter conditions because they are larger than females.
Birds returning north in spring across the central Mediterranean appear to follow a well-defined route. Large concentrations of Ruffs form every year at particular stopover
Layover
In transportation, a layover, also known as lays over or stopover, is some form of a break between parts of a single trip.-In mass transit:...
sites to feed, and individuals marked with rings
Bird ringing
Bird ringing or bird banding is a technique used in the study of wild birds, by attaching a small, individually numbered, metal or plastic tag to their legs or wings, so that various aspects of the bird's life can be studied by the ability to re-find the same individual later...
or dye reappear in subsequent years. The refuelling sites are closer together than the theoretical maximum travel distance calculated from the mean body mass, and provide evidence of a migration strategy using favoured intermediate sites. The Ruff stores fat as a fuel, but unlike mammals, uses lipid
Lipid
Lipids constitute a broad group of naturally occurring molecules that include fats, waxes, sterols, fat-soluble vitamins , monoglycerides, diglycerides, triglycerides, phospholipids, and others...
s as the main energy source for exercise (including migration) and, when necessary, keeps warm by shivering; however, little research has been conducted on the mechanisms by which they oxidise lipids.
Mating
Mendelian inheritance
Mendelian inheritance is a scientific description of how hereditary characteristics are passed from parent organisms to their offspring; it underlies much of genetics...
variations in plumage and mating behaviour. There are three male forms: the typical territorial males, satellite males which have a white neck ruff, and a very rare, recently discovered variant with female-like plumage. The territorial males, about 84% of the total, have strongly coloured black or chestnut ruffs and stake out and occupy small mating territories in the lek. They actively court females and display a high degree of aggression towards other resident males; 5–20 territorial males each hold an area of the lek about 1 m (1 yd) across, usually with bare soil in the centre. They perform an elaborate display that includes wing fluttering, jumping, standing upright, crouching with ruff erect, or lunging at rivals. They are typically silent even when displaying, although a soft gue-gue-gue may occasionally be given.
Territorial
Territory (animal)
In ethology the term territory refers to any sociographical area that an animal of a particular species consistently defends against conspecifics...
males are very site-faithful; 90% return to the same lekking sites in subsequent seasons, the most dominant males being the most likely to reappear. Site-faithful males can acquire accurate information about the competitive abilities of other males, leading to well-developed dominance relationships. Such stable relationships reduce conflict and the risk of injury, and the consequent lower levels of male aggression are less likely to scare off females. Lower-ranked territorial males also benefit from site fidelity since they can remain on the leks while waiting for the top males eventually to drop out.
Satellite males, about 16% of the total number, have white or mottled ruffs and do not occupy territories; they enter leks and attempt to mate with the females visiting the territories occupied by the resident males. Resident males tolerate the satellite birds because, although they are competitors for mating with the females, the presence of both types of male on a territory attracts additional females. Females also prefer larger leks, and leks surrounded by taller plants, which give better nesting habitat.
The behaviour and appearance for an individual male remain constant through its adult life, and are determined by a simple genetic polymorphism
Polymorphism (biology)
Polymorphism in biology occurs when two or more clearly different phenotypes exist in the same population of a species — in other words, the occurrence of more than one form or morph...
. It was originally thought that the difference between the two types of males was due to a sex-linked genetic factor, but in fact the genetic locus
Locus (genetics)
In the fields of genetics and genetic computation, a locus is the specific location of a gene or DNA sequence on a chromosome. A variant of the DNA sequence at a given locus is called an allele. The ordered list of loci known for a particular genome is called a genetic map...
relevant for the mating strategy is located on an autosome
Autosome
An autosome is a chromosome that is not a sex chromosome, or allosome; that is to say, there is an equal number of copies of the chromosome in males and females. For example, in humans, there are 22 pairs of autosomes. In addition to autosomes, there are sex chromosomes, to be specific: X and Y...
, or non-sex chromosome
Chromosome
A chromosome is an organized structure of DNA and protein found in cells. It is a single piece of coiled DNA containing many genes, regulatory elements and other nucleotide sequences. Chromosomes also contain DNA-bound proteins, which serve to package the DNA and control its functions.Chromosomes...
. That means that both sexes can carry the two different forms of the gene, not just males. The non-territorial female does not normally show evidence of its genetic type, but when females are given testosterone
Testosterone
Testosterone is a steroid hormone from the androgen group and is found in mammals, reptiles, birds, and other vertebrates. In mammals, testosterone is primarily secreted in the testes of males and the ovaries of females, although small amounts are also secreted by the adrenal glands...
implants, they display the male territorial behaviour corresponding to their genotype
Genotype
The genotype is the genetic makeup of a cell, an organism, or an individual usually with reference to a specific character under consideration...
. Territorial plumage and behaviour are inherited as recessive characteristics.
Although satellite males are on average slightly smaller and lighter than residents, the nutrition of the chicks does not, as previously thought, influence mating strategy; rather, the inherited mating strategy influences body size. Resident-type chicks will, if provided with the same amount of food, grow heavier than satellite-type chicks. Satellite males do not have to expend energy to defend a territory, and can spend more time foraging, so they do not need to be as bulky as the residents; indeed, since they fly more, there would be a physiological cost to additional weight.
A third type of male was first described in 2006; this is a permanent female mimic, the first such reported for a bird. About 1% of males are small, intermediate in size between males and females, and do not grow the elaborate breeding plumage of the territorial and satellite males, although they have much larger internal testes
Testicle
The testicle is the male gonad in animals. Like the ovaries to which they are homologous, testes are components of both the reproductive system and the endocrine system...
than the ruffed males. This cryptic male, or "faeder" (Old English "father") obtains access to mating territories together with the females, and "steals" matings when the females crouch to solicit copulation. The faeder moults into the prenuptial male plumage with striped feathers, but does not go on to develop the ornamental feathers of the normal male. As described above, this stage is thought to show the original male breeding plumage, before other male types evolved. A faeder can be distinguished in the hand by its wing length, which is intermediate between those of displaying males and females. Despite their feminine appearance, the faeders migrate with the larger 'normal' lekking males and spend the winter with them.
The faeders are sometimes mounted by independent or satellite males, but are as often "on top" in homosexual mountings as the ruffed males, suggesting that their true identity is known by the other males. Females never mount males. Preliminary research results suggest that the faeder characteristics are genetically controlled by a single dominant gene. Females often seem to prefer mating with faeders to copulation with normal males, and normal males also copulate with faeders (and vice versa) relatively more often than with females. The homosexual copulations may attract females to the lek, like the presence of satellite males.
Not all mating takes place at the lek, since only a minority of the males attend an active lek. As alternative strategies, males can also directly pursue females ("following") or wait for them as they approached good feeding sites ("intercepting"). Males switched between the three tactics, being more likely to attend a lek when the copulation rate the previous day was high or when fewer females were available after nesting had started. Lekking rates were low in cold weather early in the season when off-lek males spent most of their time feeding.
The level of polyandry
Polyandry
Polyandry refers to a form of marriage in which a woman has two or more husbands at the same time. The form of polyandry in which a woman is married to two or more brothers is known as "fraternal polyandry", and it is believed by many anthropologists to be the most frequently encountered...
in the Ruff is the highest known for any avian lekking species and for any shorebird. More than half of female Ruffs mate with, and have clutches fertilised by, more than one male, and individual females mate with males of both main behavioural morphs more often than expected by chance. In lekking species, females can choose mates without risking the loss of support from males in nesting and rearing chicks, since the males take no part in raising the brood anyway. In the absence of this cost, if polyandry is advantageous, it would be expected to occur at a higher rate in lekking than among pair-bonded species.
Nesting and survival
The typical clutch is four eggs, each egg measuring 44 x 31 mm (1.7 x 1.2 in) in size and weighing 21.0 g (0.75 oz) of which 5% is shell. Incubation is by the female alone, and the time to hatching is 20–23 days, with a further 25–28 days to fledging. The precocial
Precocial
In biology, the term precocial refers to species in which the young are relatively mature and mobile from the moment of birth or hatching. The opposite developmental strategy is called "altricial," where the young are born or hatched helpless. Extremely precocial species may be called...
chicks have buff and chestnut down, streaked and barred with black, and frosted with white; they feed themselves on a variety of small invertebrates, but are brooded by the female. One brood is raised each year.
Predators of waders breeding in wet grasslands include birds such as large gulls, Common Raven
Common Raven
The Common Raven , also known as the Northern Raven, is a large, all-black passerine bird. Found across the northern hemisphere, it is the most widely distributed of all corvids...
, Carrion
Carrion Crow
The Carrion Crow is a member of the passerine order of birds and the crow family which is native to western Europe and eastern Asia.-Taxonomy:...
and Hooded Crow
Hooded Crow
The Hooded Crow is a Eurasian bird species in the crow genus. Widely distributed, it is also known locally as Scotch Crow, Danish Crow, and Corbie or Grey Crow in Ireland, which is what its Welsh name, Brân Lwyd, translates as...
s, and Great
Great Skua
The Great Skua, Stercorarius skua, is a large seabird in the skua family Stercorariidae. In Britain, it is sometimes known by the name Bonxie, a Shetland name of unknown origin.-Description:...
and Arctic Skua
Arctic Skua
The Parasitic Jaeger, also known as the Arctic Skua or Parasitic Skua, is a seabird in the skua family Stercorariidae....
s; foxes occasionally take waders, and the impact of feral cats and stoats is unknown. Overgrazing can increase predation by making nests easier to find. In captivity, the main causes of chick mortality were stress-related sudden death and twisted neck syndrome
Torticollis
Torticollis, or wryneck, is a stiff neck associated with muscle spasm, classically causing lateral flexion contracture of the cervical spine musculature...
. Adults seem to show little evidence of external parasites
Parasitism
Parasitism is a type of symbiotic relationship between organisms of different species where one organism, the parasite, benefits at the expense of the other, the host. Traditionally parasite referred to organisms with lifestages that needed more than one host . These are now called macroparasites...
, but may have significant levels of disease on their tropical wintering grounds, including avian malaria
Avian malaria
Avian malaria is a parasitic disease of birds.-Etiology:Avian malaria is most notably caused by Plasmodium relictum, a protist that infects birds in tropical regions...
in their inland freshwater habitats, and so they might be expected to invest strongly in their immune system
Immune system
An immune system is a system of biological structures and processes within an organism that protects against disease by identifying and killing pathogens and tumor cells. It detects a wide variety of agents, from viruses to parasitic worms, and needs to distinguish them from the organism's own...
s; however, a 2006 study that analysed the blood of migrating Ruffs intercepted in Friesland
Friesland
Friesland is a province in the north of the Netherlands and part of the ancient region of Frisia.Until the end of 1996, the province bore Friesland as its official name. In 1997 this Dutch name lost its official status to the Frisian Fryslân...
showed that this bird actually has unexplained low levels of immune responses on at least one measure of resistance. The Ruff can breed from its second year, and the average lifespan
Life expectancy
Life expectancy is the expected number of years of life remaining at a given age. It is denoted by ex, which means the average number of subsequent years of life for someone now aged x, according to a particular mortality experience...
for birds that have passed the chick stage is about 4.4 years, although a Finnish bird lived to a record 13 years and 11 months.
Feeding
The Ruff normally feeds using a steady walk and pecking action, selecting food items by sight, but it will also wade deeply and submerge its head. On saline lakes in East Africa it often swims like a phalaropePhalarope
A phalarope or wadepiper is any of three living species of slender-necked shorebirds in the genus Phalaropus of the bird family Scolopacidae. They are close relatives of the shanks and tattlers, the Actitis and Terek Sandpipers, and also of the turnstones and calidrids...
, picking items off the surface. It will feed at night as well as during the day. When feeding, the Ruff frequently raises its back feathers, producing a loose pointed peak on the back; this habit is shared only by the Black-tailed Godwit.
Trichoptera
The caddisflies are an order, Trichoptera, of insects with approximately 12,000 described species. Also called sedge-flies or rail-flies, they are small moth-like insects having two pairs of hairy membranous wings...
, water-beetles, mayflies
Mayfly
Mayflies are insects which belong to the Order Ephemeroptera . They have been placed into an ancient group of insects termed the Palaeoptera, which also contains dragonflies and damselflies...
and grasshoppers), crustaceans, spiders, molluscs, worms, frogs, small fish, and also the seeds of rice and other cereals, sedges, grasses and aquatic plants. Migrating birds in Italy varied their diet according to what was available at each stopover site. Green aquatic plant material, spilt rice and maize, flies and beetles were found, along with varying amounts of grit. On the main wintering grounds in West Africa, rice is a favoured food during the later part of the season as the ricefields dry out.
Just before migration, the Ruff increases its body mass at a rate of about 1% a day, much slower than the Bar-tailed Godwits breeding in Alaska, which fatten at four times that rate. This is thought to be because the godwit cannot use refuelling areas to feed on its trans-Pacific flight, whereas the Ruff is able to make regular stops and take in food during overland migration. For the same reason, the Ruff does not physiologically shrink its digestive organs to reduce bodyweight before migrating, unlike the godwit.
Relationship with humans
...if expedition is required, sugar is added, which will make them in a fortnight's
time a lump of fat: they then sell for two Shillings or half-a-crown a piece… The method of killing them is by cutting off their head with a pair of scissars, the quantity of blood that issues is very great, considering the size of the bird. They are dressed like the Woodcock, with their intestines; and, when killed at the critical time, say the Epicures, are reckoned the most delicious of all morsels.
The heavy toll on breeding birds, together with loss of habitat through drainage and collection by nineteenth-century trophy hunters and egg collectors, meant that the species became almost extinct in England by the 1880s, although recolonisation in small numbers has occurred since 1963. The draining of wetlands from the 1800s onwards in southern Sweden has resulted in the Ruff's disappearance from many areas there, although it remains common in the north of the country. The use of insecticide
Insecticide
An insecticide is a pesticide used against insects. They include ovicides and larvicides used against the eggs and larvae of insects respectively. Insecticides are used in agriculture, medicine, industry and the household. The use of insecticides is believed to be one of the major factors behind...
s and draining of wetlands has led to a decrease in the number of Ruff in Denmark since the early 1900s. There are still areas where the Ruff and other wetland birds are hunted legally or otherwise for food. A large-scale example is the capture of more than one million waterbirds (including Ruffs) in a single year from Lake Chilwa
Lake Chilwa
Lake Chilwa is the second-largest lake in Malawi after Lake Malawi. It is in eastern Zomba District, near the border with Mozambique. Approximately 60 km long and 40 km wide, the lake is surrounded by extensive wetlands....
in Malawi
Malawi
The Republic of Malawi is a landlocked country in southeast Africa that was formerly known as Nyasaland. It is bordered by Zambia to the northwest, Tanzania to the northeast, and Mozambique on the east, south and west. The country is separated from Tanzania and Mozambique by Lake Malawi. Its size...
.
Although this bird eats rice on the wintering grounds, where it can make up nearly 40% of its diet, it takes mainly waste and residues from cropping and threshing, not harvestable grain. It has sometimes been viewed as a pest, but the deeper water and presence of invertebrate prey in the economically important early winter period means that the wader has little effect on crop yield.
Conservation status
The Ruff has a large range, estimated at 1–10 million square kilometres (0.38–3.8 million square miles) and a population of at least 2,000,000 birds. The European population of 200,000–510,000 pairs, occupying more than half of the total breeding range, seems to have declined by up to 30% over ten years, but this may reflect geographical changes in breeding populations. Numbers in Asia do not appear to be declining, and more Ruffs are wintering in Africa. The species as a whole is therefore not believed to approach the thresholds for the population decline criterion of the IUCN Red ListIUCN Red List
The IUCN Red List of Threatened Species , founded in 1963, is the world's most comprehensive inventory of the global conservation status of biological species. The International Union for Conservation of Nature is the world's main authority on the conservation status of species...
(that is, declining more than 30 percent in ten years or three generations). For these reasons, the Ruff is classified as "least concern
Least Concern
Least Concern is an IUCN category assigned to extant taxon or lower taxa which have been evaluated but do not qualify for any other category. As such they do not qualify as threatened, Near Threatened, or Conservation Dependent...
".
Fossils from the Pleistocene
Pleistocene
The Pleistocene is the epoch from 2,588,000 to 11,700 years BP that spans the world's recent period of repeated glaciations. The name pleistocene is derived from the Greek and ....
suggest that this species bred further south in Europe in the cool periods between glaciations than it does now. Its sensitivity to changing climate as well as to water table levels and the speed of vegetation growth has led to suggestions that its range is affected by global warming, and the Ruff might act as an indicator species for monitoring climate change. Potential threats to this species may also include outbreaks of diseases to which it is susceptible such as influenza, botulism
Botulism
Botulism also known as botulinus intoxication is a rare but serious paralytic illness caused by botulinum toxin which is metabolic waste produced under anaerobic conditions by the bacterium Clostridium botulinum, and affecting a wide range of mammals, birds and fish...
and avian malaria
Avian malaria
Avian malaria is a parasitic disease of birds.-Etiology:Avian malaria is most notably caused by Plasmodium relictum, a protist that infects birds in tropical regions...
.
The Ruff is one of the species to which the Agreement on the Conservation of African-Eurasian Migratory Waterbirds (AEWA) applies, where it is allocated to category 2c; that is, the populations in need of special attention as they are showing "significant long-term decline" in much of its range. This commits signatories to regulate the taking of listed species or their eggs, to establish protected areas to conserve habitats for the listed species, to regulate hunting and to monitor the populations of the birds concerned.
External links
- Image documentation
- Mating strategy introduction and research
- Ruffs on postage stamps: www.birdtheme.org and www.bird-stamps.org