Abstract
Food limitation is traditionally though to be a major influence both in regulating contemporary bird populations and in determining avian life history variation between species. However, nest predation is a significant source of early mortality in life and changes in predation rates should potentially exert a strong influence on bird numbers and avian life history evolution. Rapid changes of predation rates through human disturbance of natural environments could disrupt the fecundity-mortality balance of many species and may thus lead to the long-term decline of common species currently observed in Swedish populations of Willow- Parus montanus and crested tits Parus cristatus. In general, however, the interactive mechanisms linking predation and habitat change to population dynamics remain to be understood. In this project I will focus on the role of human-induced reductions in the quality and quantity of natural nest sites, predator protective cover and food supply through forest thinning for reproductive success and annual survival in Parus species. In this context, I will explore the effect of life history traits on the ability of individuals among woodland species (e.g. Paridae, Sylvidae, Turdidae) to behaviourally influence the risk of predation, a question that has received little attention yet.
Sweden