Understanding the factors that limit and regulate wildlife populations requires insight into demographic and environmental processes acting throughout the annual cycle. Here, we combine multi-year tracking data of individual birds with a 26-year demographic study of a migratory songbird to evaluate the relative effects of density and weather at the breeding and wintering grounds on population g...

Migrating long distances requires time and energy, and may interact with an individual's performance during breeding. These seasonal interactions in migratory animals are best described in populations with disjunct nonbreeding distributions. The black-tailed godwit (Limosa limosa limosa), which breeds in agricultural grasslands in Western Europe, has such a disjunct nonbreeding distribution: Th...

during a five years survey in markazi province, 136 species related to 42 bird's family have been identified, that include 27% of the birds' species and 58% of the birds families of iran. (iranian birds). 36% of birds were endemic and 64% were migrant. cosidering the species variety in markazi province, sylvidae family is number one. the population of corvidae family are more than oth...

The onset of migration in birds is assumed to be primarily under endogenous control in long-distance migrants. Recently, climate changes appear to have been driving a rapid change in breeding area arrival. However, little is known about the climatic factors affecting migratory birds during the migration cycle, or whether recently reported phenological changes are caused by plastic behavioural r...

We examined the seasonal movements of wing-tagged and radio-marked adult female Great Bustards Otis tarda in a population in northwestern Spain. Four different movement patterns were found: females that migrated between breeding and wintering areas (20%) females that only left their year-round home range area to mate (32%), females that migrated from a wintering-mating area to a nesting-summeri...

Long-lived migratory animals must balance the cost of current reproduction with their own condition ahead of a challenging migration and future reproduction. In these species, carry-over effects, which occur when events in one season affect the outcome of the subsequent season, may be particularly exacerbated. However, how carry-over effects influence future breeding outcomes and whether (and h...

The Purple Finch (Carpodacus purpureus (Gmelin)) is a migratory fringillid breeding across the northern coniferous forests of North America. Although irruptions occur, little information has been gathered on the movements of individual birds. We used the 19,893 re-encounters of banded birds in the Bird Banding Laboratory database to identify patterns of movements and to examine wintering and br...