Thursday, September 25, 2014

Harbor Seals

Harbor Seal | Poulsbo, WA

Harbor Seals (Phoca vitulina) are found all over temerate and arctic marine coastlines of the northern Atlantic and Pacific Oceans, and the Baltic and North Seas. You can often see the laying out on the shore or docks basking in the sun to help regulate their body temperature.

Harbor seals are known to spend several days at sea finding prey fish such as anchovy, sea bass, herring, and menhaden, among other species. They will even eat the occasional crab, mollusk or squid, if needed. These seals can also be found traveling up large coastal rivers in search of food, but rarely spend ample time in fresh water.

In summer, Harbor seal mothers usually give birth to a single pup at a relatively remote haul-out site. This “pupping” occurs from July through September in southern Puget Sound, and in June and July along the Strait of Juan de Fuca and the San Juan Islands. Mother seals nurse their pup, which can be born weighing as little as 15 pounds, for three to six weeks. Their mother often leaves the pup alone on the beach while she heads back to the water for a meal, returning when she has finished catching and consuming her meal to nurse her pup with rich milk.



Harbor seal basking in the son | Poulsbo, WA


While the mother is out finding a meal, you may find the pup on the beach looking like it’s abandoned, looking at you with big, sad eyes and often crying for its mother with a sheep-like “ma-a-a”. People may assume it’s crying to them, and come close to see if the pup is in danger. In the majority of cases, the pup is far from helpless. However, since seals are largely defenseless when on land, the shy mother may not return to the beach if she sees people or dogs hanging around her baby and thinks it might be unsafe to do so.  She may also nurse the pup at night if there is human interference during the day.

Harbor seals have a very high mortality rate in their first few months of life, and up to half of all harbor seals do not survive their first year after birth. Their population in Puget Sound is very healthy, estimated at up to 14,000 seals, and the Oregon/Washington outer coast stock is estimated to be 25,000 individuals. There are 3,000 – 5,000 harbor seal pups born in Washington inland waters each year.