Harbor seal (Phoca vitulina): 9-11 months
Gray seal (Halichoerus grypus): 11-12 months
Harp seal (Pagophilus groenlandicus): 11-12 months
Hooded seal (Cystophora cristata): 11-12 months
Spotted seal (Phoca largha): 9-10 months
Ringed seal (Pusa hispida): 10-11 months
Bearded seal (Erignathus barbatus): 11-12 months
The gestation period begins when the fertilized egg implants in the female's uterus and ends when the pup is born. During gestation, the developing pup receives nutrients from the mother through the placenta.