The impact sea otters have on commercially-harvested sea cucumbers in Southeast Alaska is the subject of a newly-published research paper. The study found that sea cucumber populations have declined in areas with and without the presence of otters. However, areas with otters have seen a much greater decline, as much as 100 percent in some areas. That compares with up to a 19 percent decline in places without otters.

Sea otter predation on commercially-harvested shellfish has long been a concern for fishermen and fishery managers, but this is the first paper of its kind to document the issue in detail.

The fur trade wiped out otters by the early 20th century, but the state re-introduced the animals to the region in the 1960’s and the population has grown exponentially.

The Canadian Journal of Fisheries and Aquatic Sciences published the new paper in October. The lead author is biologist Sean Larson, who grew up in Petersburg. He completed the work for his Master’s Thesis at the University of Alaska Fairbanks last year. Matt Lichtenstein spoke with Larson by phone this week:

For mobile-friendly, downloadable audio, click here.

Sea cucumber


Larson’s co-authors included Zach Hoyt and Ginny L. Eckert with UAF as well as Verena Gill from the US Fish and Wildlife Service. Larson now works for the Alaska Department of Fish and Game as a research biologist for Yukon River Salmon.