A bluefin tuna Thunnus thynnus found washed ashore on the south beach in early April. This fish - 265 cm in length, a "giant" in tuna terminology - was at least 10 years old and was mature. Bluefin tuna are known to migrate into New England and Canadian waters in the early summer, remaining until late autumn (November and early December). Based on known distribution, this fish should not have been in the Sable Island area in March and April. Perhaps the animal failed to migrate when it should have and died from thermal shock - but we can't know why it didn't move out of the region. Also, little is known about natural mortality from old age or disease in tuna. Since we on Sable Island have little experience with, or knowledge about, tuna (except in sandwiches), we thank Greg Skomal for identifying the species and providing some background information. Greg noted that he knows of only one other giant bluefin found washed ashore, and that occurred on Martha's Vineyard over a decade ago.
(Greg Skomal, Marine Fisheries Biologist, Massachusetts Division of Marine Fisheries, Martha's Vineyard Research Station, Oak Bluffs, MA 02557)