Behavioral Reproductive Effort of Nursing Harp Seals, Phoca groenlandica

The behavior of harp seal mother-pup pairs was examined during the nursing periods from 1976 to 1982. Quantitative behavioral data (1978–1982) indicated that behavioral reproductive effort did not vary with maternal age. In all maternal age groups, most births occurred on 2 days in early March. Females tended to be on the ice with their pups most from mid-morning to late afternoon, and they spent less time on the ice on overcast and rainy days. Pups spent 70 to 90% of observation time alone. Most of this time was spent idling. Pups nursed about 5% of observation time regardless of their age. Nursing bouts lasted 6–8 min and occurred, on average, 2 to 3 h apart. The outcome of female-female agonistic encounters depended on the relative proximity of the associated pups.