Species MammalsSei Whale

Sei Whale

Balaenoptera borealis

RareMammal
Illustration of Sei Whale (Balaenoptera borealis)

The Sei Whale is a large, streamlined rorqual that appears in North American waters primarily along the edge of continental shelves during summer feeding aggregations. It is one of the fastest whales, reaching 35 mph in short bursts. Sei whales were heavily targeted by 20th-century industrial whaling and have not recovered to pre-exploitation numbers.

Habitat
Offshore open-ocean waters and continental slope edges
Diet
Copepods, krill, and small schooling fish
How common
Rare

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