Site tenacity and annual survival of a Willow WarblerPhylloscopus trochiluspopulation in Southern England

Abstract

Nine years of mark‐recapture date for Willow Warblers collected from a woodland breeding site in southern England were used to investigate site tenacity and survival. Nearly 30% of adult males and 17% of adult females were retrapped in years after ringing. Recaptures of adults, both within and between years, tended to occur in the same part of the study site, and often in the same mist net, as the first capture. Survival rates were estimated by modelling the mark‐recapture data as a product of capture probability and survival rate using program SURGE. The probability of capture differed between the sexes but not between years. There was no evidence that annual survival differed either between the sexes or between years. The average annual adult survival rate was estimated at 47.1%.