Most seal species have enough stored energy to be able to fast during nursing periods, staying out of the water for up to 6 weeks without food. Harbor seal (Phoca vitulina) moms, on the other hand, will take their pups on foraging trips while the pups are still nursing- sometimes even hours after birth!
[Photo and caption by Karli Chudeau]
Bowen, W. D., Boness, D. J., & Iverson, S. J. (1999). Diving behaviour of lactating harbour seals and their pups during maternal foraging trips. Canadian Journal of Zoology, 77, 978–988.
[Edited by Maggie Creamer]