Blue-headed Wagtail (Motacilla flava) Science Article 3 abstract Timing of pre-migratory fattening among Yellow Wagtails Motacilla flava wintering in Nigeria pre-1980 is compared with that in the period 2004-2006 to determine whether this has been affected by trends towards earlier spring phenology in Europe over the same period. Wagtails wintering in northern Nigeria showed later […]
Complex communication signals: the caseof the Blue-black Grassquit Volatinia jacarina(Aves, Emberizidae) song. Part I – A structural analysis
Blue-black Grassquit (Volatinia jacarina) Science Article 1 abstract The song of the Blue-black Grassquit Volatinia jacarina is different for every individual and the structuraldifferences between individuals are quite complex. Samples of songs from different Brazilian localities,as well as from Venezuela and Mexico, were studied through a comparative analysis of their sonograms.From the structural point of […]
The Blue-backed Tanager (Cyanicterus cyanicterus), a genus new to Venezuela, with notes on its plumages
Blue-backed Tanager (Cyanicterus cyanicterus) Science Article 1 abstract The little-known Blue-backed Tanager, Cyanicterus cyanlcterus (Vieillot), sole member of its genus, has been recorded primarily as an inhabitant of the Guianas, with an outlying record in Brazil on the lower Rio Negro near Manaus. It will undoubtedly be found eventually in the part of Brazil, ornithologically […]
SOCIALO RGANIZATIONO F THE BLUE-BACKEDMANAKIN
Blue-backed Manakin (Chiroxiphia pareola) Science Article 1 abstract The manakins of the genus Chiroxiphia are peculiar in that pairs of males (or in C. caudata several males) perform a coordinated courtship dance in which each bird appears to play an equal part. The displays take place on low perches in the undergrowth of secondary forest, […]
Molecular markers for population genetic analysesin the family Psittacidae (Psittaciformes, Aves)
Blue-and-yellow Macaw (Ara ararauna) Science Article 1 abstract The selection of molecular markers for population studies is an important tool for biodiversity conservation. The familyPsittacidae contains many endangered and vulnerable species and we tested three kinds of molecular markers fortheir potential use in population studies of five psitacid species: 43 hyacinth macaws (Anodorhynchus hyacinthinus),42 blue-and-yellow […]
LIFE HISTORY OF THE BLUE AND WHITE SWALLOW
Blue-and-white Swallow (Notiochelidon cyanoleuca) Science Article 1 abstract This Swallow has the upper plumage is dark, violaceous steel-blue; the under parts are pure white except for the blue-black under tail-coverts, the grayish-brown sides and flanks, and a few dusky spots in the center of the chest, which are lacking on some individuals. The tail is […]
FEMALE MATE CHOICE IN RELATION TO STRUCTURAL PLUMAGE COLORATION INBLUE GROSBEAKS
Blue Grosbeak (Passerina caerulea) Science Article 1 abstract Plumage blueness in Blue Grosbeaks (Passerina caerulea) is related to nutritional conditionduring molt, and bluer males hold larger territories with more food resources. We tested the hypothesis that females use male plumage brightness as a criterion in choosing mates. In a mate-choice aviary, we presented females with […]
Effects of breeding density and plumagecoloration on mate guarding and cuckoldry in bluegrosbeaks (Passerina caerulea)
Blue Grosbeak (Passerina caerulea) Science Article 3 abstract For species in which females mate outside of the pair bond, selection should favor male mate-guarding behaviors that minimize investment in genetically unrelated offspring. Mate guarding may impose costs by diverting time and energy from activities such as foraging and seeking extra-pair copulations, so males should adjust […]
Ecological relationships between feather mites (Acari) and wild birds ofEmberizidae (Aves) in a fragment of Atlantic Forest in northeastern Brazil
Blue Dacnis (Dacnis cayana) Science Article 1 abstract The objective of this study was to investigate feather mites on birds of the Family Emberizidae, tocollect data on the ecological ectoparasite-host relationship and infestation level. A sum of 94 birds of 9 specieswas captured at the Refugio Ecologico Charles Darwin, Igarassu, Pernambuco, Brazil, from August 1996 […]
Density estimates, microhabitat selection and foraging behaviour of the endemic Blue Chaffinch Fringilla teydea teydea on Tenerife (Canary Islands)
Blue Chaffinch (Fringilla teydea) Science Article 2 abstract Point counts were used for censusing birds. Data were analysed with the DISTANCE software programs using an average detectability function. Microhabitat structure was characterized by measuring 11 variables in a 25m radius at each point. We used Poisson regression models to predict counts for Blue Chaffinch from […]