Fox Sparrow (Passerella iliaca) Science Article 3 abstract Ontogeny of two morphologically differentiated populations of Fox Sparrows (PassereNail iaca) was compared to reveal the developmental bases of adult morphologicaldifferences. Growth of tarsus, wing, bill, and tail length relative to body mass was compared between the two populations to determine if geographic variation in adults results […]
Category: Passeriformes
Natural death of a Fox Sparrow
Fox Sparrow (Passerella iliaca) Science Article 4 abstract In ‘The Condor,’ September 1924, Laurence M. Huey describes the natural death of an Audubon’s Warbler (Dendroica auduboni) under the title ‘The Natural End of a Bird’s Life.’ Huey describes the bird as ‘ascending a vertical rose stem in a peculiar spiral manner’ and otherwise conducting itself […]
Environmental factors determine numbers of overwintering European Stonechats Saxicola rubicola: A long-term study.
European Stonechat (Saxicola rubicola) Science Article 3 abstract In this study the relationship between the number of European Stonechats Saxicola rubicola at a winter site in Israel and the local rainfall, air temperature, and arthropod abundance was examined. In some years population size declined to about one third of the initial size, while in others […]
Timing of molt as a buffer in the avian annual cycle
European Stonechat (Saxicola rubicola) Science Article 1 abstract Birds in seasonal environments must time stages in their annual life cycles precisely. While the fitness costs ofmistimed reproduction and migration are widely recognized, molt has been viewed as a more flexible element. Birds modify thetiming of molt in various ways to keep to overall timetables, but […]
Gonadal status upon spring arrival in long-distance and short-distancemigrating stonechats ( Saxicola torquata)
European Stonechat (Saxicola rubicola) Science Article 2 abstract Long-distance migration is often associated with relatively short breeding seasons and a start of reproductive activities shortly after arrival. The full activation of the reproductive system from the regressed state takes, however, several weeks and must, therefore, be initiated in the winter quarters or during spring migration. […]
Reduced take-off ability in robins (Erithacus rubecula)due to migratory fuel load
European Robin (Erithacus rubecula) Science Article 1 abstract Recent studies have shown that large fuelloads in small birds impair
Territoriality as a paternity guard in the European robin,Erithacus rubecula
European Robin (Erithacus rubecula) Science Article 5 abstract To investigate the relative importance of paternity defences in the European robin we used behaviouralobservations, simulated intrusions and temporary male removal experiments. Given that paired malesdid not increase their mate attendance, copulation rate or territory size during the female’s fertile period,the most frequently quoted paternity assurance strategies […]
Food availability as a determinant of pairing behaviour in the European robin.
European Robin (Erithacus rubecula) Science Article 4 abstract no abstract Tobias, J.A, Journal of Animal Ecology 66: 629-639 Download article download full text (pdf)
Distribution of Robins Erithacus rubecula in wintering grounds: Effects of conspecific density, migratory status and age.
European Robin (Erithacus rubecula) Science Article 2 abstract This paper studies how population density affects the dynamics of habitat occupation by Robins in a wintering area of southern Spain (Gibraltar area), and how the between-habitat distribution is influenced by the age and migratory behaviour of birds (whether they are year-round residents or wintering migrants). We […]
GENETIC DETERMINATION OF PARTIAL MIGRATION IN THE EUROPEAN ROBIN (ERITHACUS RUBECULA)
European Robin (Erithacus rubecula) Science Article 3 abstract Partially migratory behavior, the occurrence of resident and migratory individuals in a population, has been reported in free-living birds. I examined this behavior in the European Robin (Erithacus rubecula) under controlled experimental conditions. In an offspring group from a partially migratory field population, 36 (78%) individuals exhibited […]