Serin (Serinus serinus) Science Article 2 abstract Given that in many bird species females are subordinate to males and that, in general, subordinate individuals are more vigilant than dominants ones, we should predict foraging females to be more vigilant than males. This prediction is tested here in flocks of Serins Serinus serinus, where several males […]
Category: Passeriformes
THE RUFOUS-COLLARED SPARROW AS A HOST OF THE SHINY COWBIRD
Shiny Cowbird (Molothrus bonariensis) Science Article 5 abstract The Rufous-collared Sparrow or Chingolo (Zonotrichia cupensis) is one of the main hosts of the Shiny Cowbird (Molothrus bonariensis) through most of their overlapping range in South America. The most recent study on the interaction between these species was carried out by King (1973) in Horco Molle, […]
THE SHINY COWBIRD (MOLOTHRUS BONARIENSIS) IN CHILE:INTRODUCTION OR DISPERSION? ITS HOSTS AND PARASITICTRENDS
Shiny Cowbird (Molothrus bonariensis) Science Article 4 abstract I analyzed the origin, distribution, and hosts of the Shiny Cowbird (Molothrus bonairensis) in Chile, using specimen records and the literature. It is more likely that the species was introduced to Chile before natural dispersal could take place from Argentina. The earliest specimens are from mid-1865 and […]
SHINY COWBIRD PARASITISM IN CENTRAL BRAZIL
Shiny Cowbird (Molothrus bonariensis) Science Article 6 abstract Recent human settlement in Brasilia, Central Brazil, has greatly reduced the extent of native cerrado vegetation. This has favored the Shiny Cowbird, Molothrus bonariensis,which is common in farmland and certain urban sites. Between September and December of 1982 to 1984, we observed cowbird nestlings(n) or fledglings(f) attended […]
Survival rates of adult Reed Warblers Acrocephalus scirpaceus at a northern and southern site in England
Sedge Warbler (Acrocephalus schoenobaenus) Science Article 10 abstract Mark-recapture ringing data from Wicken Fen in Cambridgeshire and Gosforth Park in Newcastle upon Tyne were used to estimate adult survival rates in a southerly and a northerly population of Reed Warblers in England. The computer program MARK was used to estimate survival and recapture rates, adjusted […]
Movement patterns of European Reed Warblers Acrocephalus scirpaceus and Sedge Warblers A. schoenobaenus before and during autumn migration.
Sedge Warbler (Acrocephalus schoenobaenus) Science Article 9 abstract The foraging movements of European Reed Warblers Acrocephalus scirpaceus and Sedge Warblers Acrocephalus schoenobaenus at migratory stopover sites were studied by comparing the frequency distribution of distances between capture-recapture localities of individual birds with a simulation model of a random distribution of movements. The results indicate that […]
Stabilising selection on wing length in reed warblers Acrocephalus
Sedge Warbler (Acrocephalus schoenobaenus) Science Article 5 abstract The size of an animal is of utmost importance for its overall success and each species isthought to have its own optimal size. If this is true, size traits ought to be understabilising selection unless the animal is living in a highly unstable environment. Winglength is a […]
Song and the song control pathway in the brain can develop independently of exposure to song in the sedge warbler
Sedge Warbler (Acrocephalus schoenobaenus) Science Article 7 abstract Previous studies have shown that female sedge warblers choose to mate with males that have more complexsongs, and sexual selection has driven the evolution of both song complexity and the size of the majorsong control area (HVc) in the brain. In songbirds, learning from conspeci? cs plays […]
Fat and pectoral muscle in migrating Sedge Warblers Acrocephalus schoenob nus
Sedge Warbler (Acrocephalus schoenobaenus) Science Article 1 abstract Increases in fat and pectoral muscle mass are important physiological changes associated with migration, but the extent to which these are linked is uncertain. The relationship between fat and pectoral muscle in first-year Sedge Warblers Acrocephalus schoenob nus was investigated using the carcasses of 20 birds that […]
Dutch Sedge Warblers Acrocephalus schoenobaenus and West-African rainfall: Empirical data and simulation modelling show low population resilience in fragmented marshlands.
Sedge Warbler (Acrocephalus schoenobaenus) Science Article 8 abstract Sedge Warbler populations in The Netherlands have declined dramatically over the last 25 years, especially between 1973-75 and 1982-85. Population declines correlate with yearly rainfall in the western part of the Sahel-Soudan zone, the most probable wintering area of West-European birds (after removing effects of autocorrelation, rs […]