Scientific papers published using RAS data
About the seasonal survival of suburban blackbirds
Summary: Survival is a key demographic parameter in bird populations yet remarkably little is known about the seasonal pattern of survival. Mortality may increase as a result of breeding behaviour, harsh environmental conditions, resource limitation or any combination of these; knowing which is important for understanding the ecology of population change. We analyse an intensive ten-year colour marking programme of European blackbirds Turdus merula to estimate seasonal and sex-specific survival rates. The annual survival rate (0.67) was similar to that produced from analyses of dead recoveries across Britain, but within year variation was significant. Survival rates were lowest during the early part of the breeding period and highest in the autumn, but there was little difference between the sexes. Understanding this pattern of variation is important in interpreting both life-history variation and the mechanisms of population change.
How African rain affects the survival of Swallow, House Martin and Sand Martin
rainfall in Britain, suggesting that overwinter food resources may be more limiting.
Robinson, R.A., Balmer, D.E. & Marchant, J.H. 2008. Survival rates of hirundines in relation to British and African rainfall.Ringing & Migration24:1–6
BTO Data Reports
Our reports provide rigorous scientific information to inform Environmental Impact Assessments in the UK.
One bird, twelve journeys, 60 000 miles and invaluable scientific data: PJ the Cuckoo has left an incredible legacy.