The Arctic supports a diversity of breeding birds. Since the mid-twentieth century,
anthropogenic-source climate change, industrial activity and harvest have impacted this …

Circulating sex steroid concentrations vary dramatically across the year in seasonally
breeding animals. The ability of circulating sex steroids to effect muscle function can be …

Numerous studies of spring migration have discovered that environmental conditions
experienced on the wintering grounds and/or during vernal migration itself can have “carry …

Abstract Marsh Tits Poecile palustris were studied in primaeval fragments of Białowieża
National Park (Poland) between 1997 and 2020 to investigate how variation in spring …

Breeding success of birds depends on survival during two critical stages of the reproductive
period: First, egg laying and incubation, and then nestling and fledgling. This essential …

In the southern Kalahari Desert, cooperatively breeding Southern Pied Babblers Turdoides
bicolor frequently build their nests and forage in camelthorn trees Vachellia erioloba, a …

Climatic factors act on populations at multiple timescales leading to the separation of long-
term climate and shorter-term weather effects. We used passerine counts from 1995 to 2019 …

Climate warming can substantially impact embryonic development and juvenile growth in
oviparous species. Estimating the overall impacts of climate warming on oviparous …

Corticosterone affects physiology and behavior both during normal daily processes but also
in response to environmental challenges and is known to mediate life history trade-offs …

In many passerine birds, testosterone stimulates song and aggression but inhibits paternal
care, but few studies have explored whether such effects can be reversed with testosterone …