The effects of site, supplemental food, and age on survivorship of Carolina Chickadees and implications for dispersal through- riparian corridors

Few studies have examined survivorship of animals in forest fragments differing in size, and none has used appropriate mark-recapture analysis techniques taking into account probability of recapture. Using Program MARK, a flexible mark-recapture software package, we estimated annual survival rates of Carolina Chickadees over a 5-yr period in a fragmented landscape in Ohio. The probability of survival was related to site (riparian woodland or woodlot area) and increased with the presence of supplemental food. While there was little evidence for an age difference in apparent survival in woodlots, young birds appeared to survive less well in forested river corridors. This last result was quite likely due, at least in part, to age-specific dispersal, suggesting that river corridors function as important dispersal routes for young birds.