Harp seals (Pagophilus
groenlandicus) are famous for being white and fluffy, which makes them
adorable; but did you know that the white harp seals we see are pups? Adults on
the other hand are black-faced with silver-gray body [1].
(Young harp seal suckling, photo by M. Watson posted www.arkive.org) |
Like any other mammal, there is a special
bond formed between the mother and her young. In the case of harp seals, the
mother “noses” its offspring immediately after its birth not only to recognize
its scent but also for her to be able to find her pup after foraging [2, 5]. Foraging
takes a few hours a day and the mothers need to eat more during the nursing
phase (which lasts about 12 days) to provide milk to their pups [3, 4, 5]. They
also use their sense of smell to protect their young by detecting predators on
ice [1], and to get back to their pups in case there is a need to relocate them
due to the unstable ice floe where they gave birth on. [6]
Newborns are sedentary and weigh around 20
lbs which is almost nothing compared to a well fed adult at around 300 lbs. [2,
6] The pups can gain an average of 5.5 lbs per day, because their mother’s milk
contains 25 to 40% fat in comparison to a cow’s milk that only contains 5% fat [2].
As soon as the pup fattens up and the nursing period ends, they are then ready
to live on their own. The mothers swim off leaving them on the ice in search of
a new mate.
Quite a short time to start becoming
independent, huh?
To know more about harp seals, visit SeaLifeBase.
__________________________
[1] Lavigne, D.M. (2009) Harp seal Phoca groenlandica. In pp. 542-546, Perrin,
W.F., Wursig, B., Thewissen, J.G.M. (2009) Encyclopedia of Marine Mammals,
Second Edition. Academic Press: London .
1316pp.
[2] Dougan,
J.L., & Roland, K. (1982). The Ice Lover: Biology of the Harp Seal (Phoca groenlandica). Science, New Series 215(4535):928-933.
[3] Ellis, R. (2003). The Empty Ocean .
Island Press, 367p.
[4] Innes, S., Lightfoot, N., &
Stewart, R. E. A. (1981). Parturition in Harp Seals. Journal of Mammology
62(4):845-850.
[5] Lydersen, C. & Kovacs, K. M. (1999). Behaviour and energetics of
icebreeding,
[6] Van Opzeeland, & I.C., Van Parijs,
S.M. (2004) Individuality in harp seal, Phoca
groenlandica, pup vocalizations. Animal
Behaviour 68:1115-1123.
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