DOMINANCE AND SURVIVAL OF DIPPERS CINCLUS-CINCLUS

Survival of dippers Cinclus cinclus in the wild was studied in relatio n to their dominance. Dominance was assessed amongst groups of tempora ry captives in a laboratory arena. Adults tended to be more dominant t han juveniles, and within age classes males generally dominated female s. Dominant individuals also sang more. Logistic regression was used t o examine survival in the wild in relation to dominance and other fact ors. Annual survival of juvenile males was negatively related to domin ance during the previous autumn. No significant effects of dominance o n winter or annual survival were found amongst females or adult males. Dominance effects on overwinter survival approached significance for adult females, however, and were significant for both winter and annua l survival when the data from adult females and juvenile males were co mbined. None of the other factors considered, which included body size , song frequency and year, had a significant effect on overwinter or a nnual survival. We concluded that dominance either had no influence on survival, or had a negative effect particularly on dippers of interme diate status. We were unable to show if dominance had a direct effect, however, or acted indirectly on survival via an unidentified factor w e did not examine.