Demography of Capercaillie Tetrao urogallus in North-East Scotland. III. Production and Recruitment of Young

Publisher Website
Google Scholar
Abstract
Changes in density of old Capercallie between winters t and t + 1 were related to the proportion of young birds in the population in winter t. These changes could be predicted from previously calculated rates of loss. It was inferred that the main factor affecting densities of old birds in winter t + 1 was the proportion of young ones recruited into the population in winter t. This proportion, however, bore no relation to breeding success in summer t. It seemed that varying rates of loss of young birds between summer and winter were important in determining densities, might involve much emigration, and are poorly understood.