The Ocean

Update: Sea Otter Census Numbers Rise

July 1, 2003

Since our story went to press, there’s been some good news for the Southern Sea Otter: census numbers for the California population soared by 17 percent since last year. More than 2,500 otters were counted off our coast this spring, the highest number recorded since current census methods were implemented in 1983.

While the dramatic increase is encouraging, scientists caution that it does not necessarily mean that the sea otter population is on the rebound. Census numbers have been highly variable the past few years, and factors such as viewing conditions and the experience level of the observers can influence the tally.

Monterey Bay accounted for most of the spike in otter numbers, with a smaller increase seen in Estero Bay (near Morro Bay) in southern California. Scientists speculate that temporary conditions, such as harsh winter weather along the open coast, or a bumper crop of Dungeness crabs in Monterey Bay, may have driven otters into the bays.

The observed increase is very surprising because a record number of of otter strandings were also observed in 2003. One possible explanation, according to Fish and Wildlife Service biologist Greg Sanders, could be that more otters living in the bays meant more dead otters washing up on beaches, where they are more likely to be found and reported.

The sea otter count is a joint project between the U.S. Geological Survey, the California Department of Fish and Game, the U.S. Fish and Wildlife Service, the Monterey Bay Aquarium, and other agencies. Census data and other info on the otters can be found at

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