The Pacific Northwest has many marine mammal species- Orca, whales, dolphins, porpoises, and several Pinnipeds, including seals and sea lions. One of the most common is the Harbor seal (Phoca vitulina). Harbor seals live year-round throughout Puget Sound, and can be seen swimming about near docks, beaches, ferries, or waterfront restaurants. They eat sole, flounder, sculpin, cod, herring, and even occasionally a Giant pacific octopus.
Starting in July each year, female harbor seals congregate in rookeries to give birth and rear their young. Harbor seal pups are born alert and can follow their mother into the water immediately after birth. Harbor seal mothers nurse their young for 4-6 weeks until they are weaned. Mother’s milk is rich and nutritious, containing 50% milk fat. Mothers will occasionally leave a pup on the beach while they forage for food. These pups are not abandoned and should never be approached or moved, as activity around the pup could cause the mother to abandon it.
The first year after weaning is a rough time for Harbor seal pups as they must learn to forage for food by themselves while relying on fat stores from nursing to keep their energy up. During this critical first year, Harbor seal pups need to rest on the beach and warm up (called hauling out) for up to 12 hours per day. They can be easily scared back into the water by human activity on the beach, causing them to waste energy instead of resting and warming up. Current guidelines are to stay away at least 100 feet from a marine mammal, including resting seal pups.
At Puget Sound dive sites, scuba divers should be alert for Harbor seal pups resting on the beach, keep their distance from the pup, and notify the local marine mammal stranding network so that volunteers can come out to watch the pup. For West Seattle dive sites and beaches, contact Seal Sitters at (206) 905-7325. For other locations, call the NOAA marine mammal hotline at (800) 853-1964.