Red-collared widowbird

The red-collared widowbird (''Euplectes ardens'') is a species of bird in the family Ploceidae. Red-collared widowbirds are found in grasslands and bush clearings in Eastern and Southern Africa. They are known for their long tails and brilliant red badges, both which act as sexual ornaments. They are often associated with other widowbird and bishop species. They are polygynous, where males acquisition of territory is an important determinant in their access to mates. Red-collared widowbirds have a wide range and there is little concern in terms of conservation status.

Taxonomy

The red-collared widowbird was described by the French polymath Georges-Louis Leclerc, Comte de Buffon in 1779 in his '' Histoire Naturelle des Oiseaux'' from a specimen collected in the Cape of Good Hope region of South Africa. The bird was also illustrated in a hand-coloured plate engraved by François-Nicolas Martinet in the ''Planches Enluminées D'Histoire Naturelle'' which was produced under the supervision of Edme-Louis Daubenton to accompany Buffon's text. Neither the plate caption nor Buffon's description included a scientific name but in 1783 the Dutch naturalist Pieter Boddaert coined the binomial name ''Fringilla ardens'' in his catalogue of the ''Planches Enluminées''. The red-collared widowbird is now one of 17 species placed in the genus '' Euplectes'' that was introduced by the English naturalist William John Swainson in 1829. The genus name combines the Ancient Greek ''eu'' "fine" or "good" and the New Latin ''plectes'' "weaver". The specific ''ardens'' is Latin for "burning" or "glowing".

Traditionally, ''Euplectes'' is thought to contain two clades, with the bishops in one clade and the widowbirds in another. However, molecular evidence suggests that the red-collared widowbird is actually a long-tailed bishop rather than a true widowbird. In captivity, they have been successfully bred with southern red bishop, yellow-mantled widowbird, fan-tailed widowbird, and black-winged red bishop.

Three subspecies are recognized:
* ''E. a. ardens'' (Boddaert, 1783) – Sierra Leone to Uganda, southwest Sudan, northwest and south Tanzania south to east South Africa
* ''E. a. laticauda'' ( Lichtenstein, MHK), 1823 – southeast Sudan, Eritrea and Ethiopia. Clemens separates this into a distinct species.
* ''E. a. suahelicus'' ( van Someren), 1921 – central Kenya to north Tanzania

The latter two taxa are treated as a separate species, the red-cowled widowbird (''Euplectes laticauda'') in the online edition of the '' Handbook of the Birds of the World''.

Description

Similar to other widowbirds, male red-collared widowbirds have both seasonal and sexual dimorphism. Males are about in length while females are only 13 centimeters. A similar trend is seen with weight, where males range from and females are only between 16 and 22 grams. During non-breeding seasons, the male plumage is brown, while in breeding season, October to April, they have black plumage with a long tail, approximately 22 cm, and crescent-shaped carotenoid based chest patch. There is significant variation in brightness, hue, and chroma of the carotenoid badges. In contrast, females and subadults, like nonbreeding males, are streaky dull brown with a short tail, approximately 4 cm. Nonbreeding males, however, retain their black tails, while females and subadults' tails are dark-brown.

Distribution and habitat

Red-collared widowbirds are found throughout Eastern and Southern Africa. While their habitats are varied, they are often found in open grasslands, agricultural areas, clearings in forests, and on slopes with limited tree coverage.

Behavior and ecology

Diet

Red-collared widowbirds feed on seeds of sorghum and other grass seeds. They also feed on nectar, small berries, and insects, specifically ants, caterpillars, and termites. They often form large roosts, with between 50 and 100 individuals, which feed together on the ground. These roosts included breeding males. They are often formed with association with other species, like red-billed quelea, fan-tailed widowbird, southern red bishop, white-winged widowbird, and yellow bishop.

Breeding and mating systems

Typical of polygynous species, male red-collared widowbirds do not provide parental care. In fact, the only resources males provide are potential nest sites in their territories. They are different from other Euplectes species in that the males use only a simple nest ring in courtship and the females build and position the actual nests. The nests are usually oval in shape and the females line the nests with grass. Females continue to add to the nest during the incubation. Old nests are often occupied by zebra waxbills. There are usually between 2 and 4 eggs in a clutch, each egg being greyish or blue-green, with brown speckles. The incubation period, done only by the female, is between 12 and 15 days. Females also do all of the feeding, primarily via regurgitation, during the nestling period for the offspring, which is between 14 and 17 days. The nests are commonly parasitized by Diederik cuckoos.

Because they are offering no other gifts, it is very important for the males to establish an exclusive territory at the beginning of the breeding season to ensure successful mating. Males aggressively defend their territories from intruders. There is no difference in costs or benefits between females who choose unmated males, monogamy, and females who settle with mated males, polygyny. Females may gain indirect benefits of picking higher quality males by producing higher-quality offspring, without suffering costs of shared territories.

Sexual ornaments

Tails

During prenuptial moulting, prior to the breeding season, the males replace their non-breeding feathers. Males that hold territory have shorter tails and carotenoid collars that are 40% larger than nonbreeding floating males . The red collar is for male-male competition, while female choice is based on tail length. Tail length is negatively correlated with carotenoid signal. Also, looking at body size and condition, this accounts for 55% of the variation in tail length. Body size may play a role in the variation of size and redness of both territorial and floater males.
Female preference for long tails was first observed in long-tailed widowbirds, and then subsequently observed in Jackson's widowbird and the red-collared widowbird. Tail length explains 47% of the male's reproductive success, indicating the strength of this sexual ornament. Tail symmetry, however, does not have an effect on mating success. In the red-collared widowbird there is a strong trade-off between carotenoid coloration, which is an agonistic signal and tail length, which is an epigamic signal, directly attracting females. These are both costly ornaments that are maintained through multiple receivers.

Plumage

The red-collared widowbird has one of the highest measured plumage carotenoid concentrations in birds. There is a high presence of lutein

HOME


Content is Copyleft
Website design, code, and AI is Copyrighted (c) 2014-2017 by Stephen Payne


Consider donating to Wikimedia



As an Amazon Associate I earn from qualifying purchases