Reproduction in the male sub-Antarctic fur seal Arctocephalus tropicalis

摘要: The reproductive tracts of male sub-Antarctic fur seals Arctocephalus tropicalis (n= 123), taken at Gough Island (40° 20'S, 9° 54'W) between November 1977 and October 1978, were examined. presence spermatozoa in the epididymal tubules showed that all males ≥4 years old had reached puberty, marked slower increase mean testis weight baculum length suggested sexual (social) maturity was approached by 8-year-olds. Full adulthood attained 10–11 age based on peak prostate weights, length. Secondary characteristics only fully developed ≥9 old. A significant decline testosterone concentration, testis, epididymis weights adult reproductively quiescent during winter from May to July when seminiferous lowest diameters with no present. Both plasma concentration peaked twice austral summer. first coincided breeding season, second moulting period impotent. Photoperiodic cueing might explain this seasonal trend.