Harbor Seals
Tracks adult harbor seal abundance in the San Francisco Bay during the breeding season
A Sentinel Species Revealing the Bay’s Ecological Health
Last Update: 2015
Harbor seals are top predators and the only year-round marine mammal resident in the Bay. They lead a dual existence in that they rest, molt, and nurse their pups on land at traditional haul out sites, but they forage at sea, often in close proximity to haul out sites. Their abundance reflects food availability and impacts from pollution and disturbance.
Harbor seals rest on a pier in San Francisco Bay while a kayaker passes by in the background, offering a glimpse of how people and wildlife can share the Bay’s dynamic waters. Ben Botkin, San Francisco Estuary Partnership.
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