Harbor seals

Harbor seals are found throughout the nearshore waters of Washington including Hood Canal, Puget Sound, the San Juan Islands, and the Strait of Juan de Fuca out to Cape Flattery. Harbor seal numbers were severely reduced during the first half of the twentieth century by a state-financed population control program. This bounty program ceased in 1960, and in 1972, harbor seals became protected under the federal Marine Mammal Protection Act (MMPA) and by Washington State. Their populations in Washington State have recovered since the 1970s and population sizes may be near a stable equilibrium level, perhaps reflective of the current carrying capacity of the environment. 

—Source: Puget Sound Science Review

Harbor seal vocalizing on rock. Credit: G.E. Davis

OVERVIEW

Harbor seal species profile

Harbor seals (Phoca vitulina) are the most commonly seen marine mammals in the Salish Sea and can be found throughout the region year round. They have been intensively studied within the Salish Sea and this species profile provides an overview of what is known about them. It was produced for the Encyclopedia of Puget Sound by the SeaDoc Society. 

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FIGURE 2. Dorsoplanar computed tomography image of conjoined fetal twins in a harbor seal (Phoca vitulina) from San Juan County, Washington, USA. The arrow points to the fusion of the spines.
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Harbor seals

Harbor seal numbers were severely reduced in Puget Sound during the first half of the twentieth century by a state-financed population control program. This bounty program ceased in 1960, and in 1972, harbor seals became protected under the federal Marine Mammal Protection Act and by Washington State.