NOAA Fisheries has declared the elevated rate of gray whale strandings on the West Coast in 2019 an Unusual Mortality Event (UME), triggering a scientific investigation into the cause.

Stranded dead gray whale at Leadbetter Point State Park, Washington, in early April. A necropsy by Portland State University’s Northern Oregon/Southern Washington Marine Mammal Stranding Program and Cascadia Research Collective found that it was unusually thin. (Image credit: John Weldon, Northern Oregon/Southern Washington Marine Mammal Stranding Program under NOAA Fisheries Marine Mammal Health and Stranding Response Program permit)