Nicaraguan Grackle
Encyclopedia
The Nicaraguan Grackle (Quiscalus nicaraguensis) is a species of passerine
bird
belonging to the genus
Quiscalus
, a genus of grackle
s in the New World blackbird family, Icterid
ae. It is found only in Nicaragua
and northernmost Costa Rica
.
and legs. The bill and legs are black and the eye is pale yellow. The male is about 31 cm long while the female is 25 cm. The adult male's plumage
is entirely black with an iridescent
gloss. The gloss is violet on the belly and tail, violet-green on the head, back and breast and blue-green on most of the wing. The tail of the male is V-shaped, rising from the centre to the outer feathers. Immature males are duller and less glossy than the adults with a brown belly and thighs. The female is brown above with a pale supercilium
(stripe over the eye), made more obvious by the dark lores and ear-coverts. The thighs, flanks and undertail-coverts
are dark brown while the rest of the underparts are buff, darkest on the upper breast and paler on the throat and belly.
The similar Great-tailed Grackle
(Quiscalus mexicanus) overlaps with it in range but is larger with a longer tail and larger bill. The male has a less green gloss than the Nicaraguan Grackle while the female is darker below and has a less obvious supercilium.
The Nicaraguan Grackle has a variety of calls including a frequent nasal call, various whistling notes and a sharp, rising whine. The song
is a series of whistles which increase in speed and frequency.
and northern Costa Rica
. It mainly occurs in the vicinity of Lake Nicaragua
and Lake Managua
but its range has expanded a little thanks to the clearance of forest and creation of pasture
s by man. It may be a fairly recent arrival in Costa Rica where it is found in the Caño Negro
area along the Río Frio. It is non-migratory
but makes some local movements in response to seasons and changes in water-level.
It nests only in marshland but will also forage in scrubland, wet pastures and along lakeshores and riverbanks.
.
It nests in small colonies
in bushes or trees or among marsh vegetation such as sedge
s. The well-hidden nest
is cup-shaped and made from grass and sedge leaves and roots. Two or three eggs
are laid; they are blue with dark markings concentrated at the larger end. Only the female incubates
the eggs but both sexes are involved in feeding the young.
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...
bird
Bird
Birds are feathered, winged, bipedal, endothermic , egg-laying, vertebrate animals. Around 10,000 living species and 188 families makes them the most speciose class of tetrapod vertebrates. They inhabit ecosystems across the globe, from the Arctic to the Antarctic. Extant birds range in size from...
belonging to the 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...
Quiscalus
Quiscalus
The avian genus Quiscalus contains six of the ten species of grackle, gregarious passerine birds in the Icterid family. They are native to North and South America...
, a genus of grackle
Grackle
Grackle can refer to any of eleven black passerine birds native to North and South America. All are members of the Icterid family but belong to multiple genera.* Genus Quiscalus** Boat-tailed Grackle, Quiscalus major...
s in the New World blackbird family, Icterid
Icterid
The Icterids are a group of small to medium-sized, often colorful passerine birds restricted to the New World. Most species have black as a predominant plumage color, often enlivened by yellow, orange or red. The family is extremely varied in size, shape, behavior and coloration...
ae. It is found only in Nicaragua
Nicaragua
Nicaragua is the largest country in the Central American American isthmus, bordered by Honduras to the north and Costa Rica to the south. The country is situated between 11 and 14 degrees north of the Equator in the Northern Hemisphere, which places it entirely within the tropics. The Pacific Ocean...
and northernmost Costa Rica
Costa Rica
Costa Rica , officially the Republic of Costa Rica is a multilingual, multiethnic and multicultural country in Central America, bordered by Nicaragua to the north, Panama to the southeast, the Pacific Ocean to the west and the Caribbean Sea to the east....
.
Description
It is a medium-sized bird with a long, graduated tail and fairly long billBeak
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...
and legs. The bill and legs are black and the eye is pale yellow. The male is about 31 cm long while the female is 25 cm. The adult male's 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...
is entirely black with an iridescent
Iridescence
Iridescence is generally known as the property of certain surfaces which appear to change color as the angle of view or the angle of illumination changes...
gloss. The gloss is violet on the belly and tail, violet-green on the head, back and breast and blue-green on most of the wing. The tail of the male is V-shaped, rising from the centre to the outer feathers. Immature males are duller and less glossy than the adults with a brown belly and thighs. The female is brown above with a pale supercilium
Supercilium
The supercilium is a plumage feature found on the heads of some bird species. It is a stripe which runs from the base of the bird's beak above its eye, finishing somewhere towards the rear of the bird's head. Also known as an "eyebrow", it is distinct from the eyestripe, which is a line which runs...
(stripe over the eye), made more obvious by the dark lores and ear-coverts. The thighs, flanks and undertail-coverts
Covert (feather)
A covert feather on a bird is one of a set of feathers, called coverts, which as the name implies, cover other feathers. The coverts help to smooth airflow over the wings and tail.- Wing-coverts :...
are dark brown while the rest of the underparts are buff, darkest on the upper breast and paler on the throat and belly.
The similar Great-tailed Grackle
Great-tailed Grackle
The Great-tailed Grackle is a medium-sized, gregarious passerine bird native to North and South America. A member of the Icteridae family, it is of the ten extant species of grackle and is closely related to the Red-bellied Grackle and the Velvet-fronted Grackle...
(Quiscalus mexicanus) overlaps with it in range but is larger with a longer tail and larger bill. The male has a less green gloss than the Nicaraguan Grackle while the female is darker below and has a less obvious supercilium.
The Nicaraguan Grackle has a variety of calls including a frequent nasal call, various whistling notes and a sharp, rising whine. The song
Bird 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...
is a series of whistles which increase in speed and frequency.
Distribution and habitat
It is restricted to western NicaraguaNicaragua
Nicaragua is the largest country in the Central American American isthmus, bordered by Honduras to the north and Costa Rica to the south. The country is situated between 11 and 14 degrees north of the Equator in the Northern Hemisphere, which places it entirely within the tropics. The Pacific Ocean...
and northern Costa Rica
Costa Rica
Costa Rica , officially the Republic of Costa Rica is a multilingual, multiethnic and multicultural country in Central America, bordered by Nicaragua to the north, Panama to the southeast, the Pacific Ocean to the west and the Caribbean Sea to the east....
. It mainly occurs in the vicinity of Lake Nicaragua
Lake Nicaragua
Lake Nicaragua or Cocibolca or Granada or is a vast freshwater lake in Nicaragua of tectonic origin. With an area of , it is the largest lake in Central America, the 19th largest lake in the world and the 9th largest in the Americas. It is slightly smaller than Lake Titicaca. With an elevation...
and Lake Managua
Lake Managua
Lake Managua is a lake in Nicaragua. The Spanish name is Lago de Managua or Lago Xolotlán. At 1,042 km², it is approximately long and wide. Similarly to the name of Lake Nicaragua, its name was coined by the Spanish conquerors from "Mangue" and agua...
but its range has expanded a little thanks to the clearance of forest and creation of pasture
Pasture
Pasture is land used for grazing. Pasture lands in the narrow sense are enclosed tracts of farmland, grazed by domesticated livestock, such as horses, cattle, sheep or swine. The vegetation of tended pasture, forage, consists mainly of grasses, with an interspersion of legumes and other forbs...
s by man. It may be a fairly recent arrival in Costa Rica where it is found in the Caño Negro
Caño Negro Wildlife Refuge
Caño Negro Wildlife Refuge is a Wildlife refuge, part of the Arenal Huetar Norte Conservation Area, in the northern part of Costa Rica twenty kilometers south of Los Chiles near the border with Nicaragua in the Alajuela province...
area along the Río Frio. It is non-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...
but makes some local movements in response to seasons and changes in water-level.
It nests only in marshland but will also forage in scrubland, wet pastures and along lakeshores and riverbanks.
Behaviour
It feeds in small groups, foraging on the ground for seeds and insects. It will turn over stones or debris to look for food underneath and often forages on or around cattleCattle
Cattle are the most common type of large domesticated ungulates. They are a prominent modern member of the subfamily Bovinae, are the most widespread species of the genus Bos, and are most commonly classified collectively as Bos primigenius...
.
It nests in small colonies
Bird colony
A bird colony is a large congregation of individuals of one or more species of bird that nest or roost in close proximity at a particular location. Many kinds of birds are known to congregate in groups of varying size; a congregation of nesting birds is called a breeding colony...
in bushes or trees or among marsh vegetation such as 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...
s. The well-hidden 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...
is cup-shaped and made from grass and sedge leaves and roots. Two or three eggs
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...
are laid; they are blue with dark markings concentrated at the larger end. Only the female incubates
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...
the eggs but both sexes are involved in feeding the young.
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