GROWTH AND REPRODUCTIVE PATTERNS IN THE SOUTH-AMERICAN FUR-SEAL

We describe patterns of age-specific growth and reproductive rates for female South American fur seals, Arctocephalus australis, in Uruguay. Females achieve body weight of 41.7 kg at 10 years of age and adult l ength of 128.9 cm at 10 years of age. Pregnancy rates showed significa nt interannual differences, suggesting effects from environmental fact ors and demographic variability. Fetuses from lactating females were s maller than fetuses from nonlactating females. We suggest that simulta neous lactation and pregnancy affect the amount of energy devoted to e mbryonic growth.