Many gray whales returning south from feeding grounds off Alaska have been passing observation posts in California and Mexico underweight, according to some scientists.
In some cases, the large bottom-feeding cetaceans were skinny enough that bones were showing, raising concerns that food stressed whales could be poised for another die off.
The eastern North Pacific stock of gray whales is one of the world’s great recovery success stories, rebounding from near extinction to get removed from the federal endangered species list. But now the fast-warming ocean off Alaska might be making food much harder to find. Or is something else at work?
So far, scientists only know that trained observers say many whales appear far too skinny for the season.
An Associated Press story this week outlined the most recent concerns by biologists, and has been picked up around the world. But a more comprehensive story appeared about two months ago in the LA Times, when the observers first began raising the alarm.
Published July 6, A Giant of the Sea Finds Slimmer Pickings reported one biologist noticing a scapula sticking out of a particularly scrawny female off San Simeon. It adds:
Scientists from Mexico to the Pacific Northwest are reporting an unusually high number of scrawny whales this year for the first time since malnourishment and disease claimed a third of the gray whale population in 1999 and 2000.
So far this year, scientists haven’t seen a decline in numbers, and they are not sure what’s causing the whales to be so thin. But they suspect it may be the same thing that triggered the die-off eight years ago: rapid warming of Arctic waters where the whales feed.