Seals...

One of the joys of Tomales Bay is the frequent sightings of harbor seals. This marine mammal hauls out along the Pacific coast from the Bering Sea to Baja California, sometimes in large numbers. Harbor seals are curious animals and often lift their heads from water to look around. They do not migrate and may be sighted year round on land or in the bay waters. Their curiosity and habit of hauling out onto land to warm themselves in the sun provides nature enthusiasts a chance for excellent wildlife sightings but also expose them to human disturbance. Harbor seals are shy animals whose habits necessary for their survival, can be easily disrupted by the presence of human activity. In Tomales Bay, favorite haul out areas are the east side of Hog Island and south Blue Gum Beach. The bay is also a major nursery for harbor seals, March through June each year brings pregnant females to the beaches to birth their pups.

Harbor seals have distinctive round heads and typically are silver, white or gray with spots but sometimes can be black or brown. They appear smaller than sea lions and lack any external ear flaps.

Harbor seals haul out daily to absorb the heat from the sun. They cannot maintain their body temperature if they stay in cold water (average Tomales Bay Temperature is 65 Fahrenheit) all the time. They also haul out to give birth. The mother seal frequently goes out to sea to feed, leaving her newborn pup alone on the beach. After the mother is fed she returns to her offspring to lavish attention on it by grooming, nuzzling, and caressing the pup. Her milk is 48% fat which helps the pup gain weight rapidly. The thick fur of the newborn pup protects it from the cold waters of the ocean enabling it to survive alone while the mother is feeding. Pups are born with the ability to swim but do not spend much time in the water until they have gained weight and learned to swim quickly.

Hauling out each day to warm up or during the year to care for their young leave harbor seals vulnerable to disturbance. The presence of humans or dogs can frighten a mother away from the pup leaving it to fend for itself and possibly starve. If a seal is not able to warm up each day, it becomes susceptible to illness and predators. If disturbed, seals may even abandon traditional haul out sites permanently as they did historic sites in San Francisco Bay.

Paddling etiquette as well as federal law prohibit approaching marine mammals and or startling or flushing them from haul out sites. A sick or injured marine mammal will interpret and approach by a person or dog as a threat, and do its best to defend itself. Never attempt to remove an animal or return it to the water. Do not wrap the animal in blankets or clothing. If you are concerned about an injured animal, telephone park visitor centers:

Tomales Bay State Park (415) 464-5137
Point Reyes National Seashore (415) 464-5100

Volunteers are needed to monitor seal populations on Tomales Bay. For information and training schedules, call the Farallones Marine Sanctuary Association at (415) 464-5137. (www.farallones.org) Seal protection measures on Tomales Bay are March 1 - June 30 when South Blue Gums Beach is closed.

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