Balaenoptera borealis (Sei Whale)  

A predominantly offshore species; Sei whales are rare in Hebridean waters. A record of a stranding in 1990 at Vacsay, West Loch Roag, Isle of Lewis is the only record on NBN Gateway for this species for the Outer Hebrides.

Additional Information
Hebridean Whale and Dolphin Trust
Cetacean Research & Rescue Unit