OBSERVATION OF COPULATION BETWEEN A NON- NESTING ADULT AND SUBADULT BALD EAGLE IN CALIFORNIA

Abstract

Bald Eagle (Haliaeetus leucocephalus) copulatory behavior has been described for wild and captive adult birds (Herrick 1932, 1934; Broley 1952; Gerrard et al. 1979; Wiemeyer 1981), but not, as far as I know, between adults and subadults. Gerrard et al. (1980) observed a marked 4-year-old female in subadult plumage adopt a copulation-solicitation posture with an adult male, but no copulation was observed. Breeding of subadults has been rarely recorded (Hoxie 1910; Bent 1937). A 3½-year-old male in adult plumage nested with an adult female and successfully fledged one young (D.A. Hammer, unpubl. data).