Robinson R.A.,Brit. Trust for Ornithol. |
Kew J.J.,9 Mackenzie Road |
Kew A.J.,9 Mackenzie Road
Journal of Avian Biology | Year: 2010
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. © 2010 The Authors. Journal compilation © 2010 Journal of Avian Biology.
Senar J.C.,Evolutionary Ecology Assoc Research Unit Csic |
Kew J.,9 Mackenzie Road |
Kew A.,9 Mackenzie Road
Bird Study | Year: 2015
Capsule We analysed ring recovery data of Siskins from the EURING database (N = 42,707 individuals) and found 18 groups of birds that moved together a median distance of 200km (range 51-1296km). The median time elapsed between capture and recovery was 21 days (range 4-1390 days). These data suggest that Siskins have stable social bonds and move in stable social units. © 2015 British Trust for Ornithology.