Predation on Birds by the Cattle Egret
1965; Oxford University Press; Volume: 82; Issue: 3 Linguagem: Inglês
10.2307/4083130
ISSN1938-4254
Autores Tópico(s)Avian ecology and behavior
ResumoVariations in plumage of male and female Pipra aureola.--Snow(Zoologica, 47: 195, 1962) states that female Golden-headed Manakins (Pipra erythrocephala) on Trinidad, West Indies, regularly have a few feathers characteristic of the male in the plumage of the head and body, and that, in birds trapped more than once, the number and distribution of these feathers remained much the same from year to year.Immature males may also have a few adult male feathers on the head and body; thus, immature males cannot be separated from adult females on the basis of plumage.I found this to apply also to Crimson-hooded Manakins (Pipra aureola) that I collected in Surinam.The adult male of this species is black, except for the head, breast, and abdomen, which are bright red shading to orange anteriorly; the female is olive green above and yellowish green below.I collected six females having red male-type feathers in their plumage: December 25, 1958.--Twobirds, each having a single red feather in the crown; ovary in both specimens undeveloped.March 27, 1960.--0nebird with numerous red feathers on the lower part of the crown and on the breast; ovary slightly enlarged.The plumage of this female is the most extreme that I have encountered.The bird was collected at the moment it alighted near two males which were sitting together on a branch.August 28, 1960.--0nebird with a single red feather in the crown; ovary undeveloped.March 15, 1962.--Twobirds, each having a single red feather in the crown; ovary in both specimens slightly enlarged.
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