Females are sexually mature at about 5-6 years old. Mating takes place in the late fall and early winter. Exact gestation period is not known, but it is somewhere around 10.5-12.5 months, and the calf nurses for 5-9 months. Calves are 4.5-4.8 m long at birth.
IUCN Red Book, NMFS/NOAA Technical Memo