Rare whale strands in Puget Sound (January, 2010)

A highly unusual stranding of a tropical Bryde’s whale occurred in southern Puget Sound this week and an examination was conducted by Cascadia Research, WDFW, and NOAA. The whale was first reported floating dead on Saturday, 16 January 2010 and temporarily came ashore in a couple of locations in southern Puget Sound over the next couple of days. The whale was towed to a remote location (thanks to the help of Taylor Shellfish) and a detailed examination conducted on the afternoon of 19 January.

This species primarily uses warmer tropical waters and in the eastern North Pacific has not generally been seen north of southern California. It appears to have been in Puget Sound several weeks because there had been several puzzling sighting reports going back at least to the beginning of January of a live whale roughly meeting the description of this whale. This is the first confirmed sighting or stranding of this species in the Pacific Northwest that we are aware of.

The whale was just under 39 feet and appeared to be an immature whale. Examination showed it had what appeared to be some healed propeller scars on its back and a likely entanglement injury on its fluke but both these were not serious and did not appear to play a role in the whales death. The whale had no food in its stomach or intestines and so did not appear to have fed in a while. The blubber layer was very thin and did not have much oil in it suggesting starvation may have played a role and possible exposure to cold (due to the small blubber layer and colder waters than is typical habitat for this animal).

Because the whale had died very recently, the tissues were very fresh and allowed a very detailed examination and sample collection. This included samples for biotoxin analysis, disease screening, contaminant testing, genetics, and histo-pathology. These tests will be run over the coming months and may provide additional insight into what the animal was doing here and why it died.

Photos of examination of dead Bryde’s whale in southern Puget Sound, Washington, 19 January 2010.

Stranded Bryde's whale on beach in south Puget Sound

Measuring stranded Bryde's whale

Necropsy of Bryde's whale

Baleen of Bryde's whale