Boat collision likely killed humpback whale that washed up near Manzanita

An autopsy performed on a dead humpback whale that washed up earlier this week south of Manzanita indicates the animal likely died after being struck by a boat.

“The team noted bleeding, bruising and swelling along the right side of the whale's head and sides,” NOAA reported in a press release. “The injuries suggest blunt impact such as a ship strike.”

Ship strikes are one of the most common causes of death for stranded humpback whales on the West Coast, according to NOAA Fisheries' most recent estimate of whale population numbers. NOAA estimates that about 5,000 humpback whales live off the coasts of Oregon, Washington and California – and their numbers are growing.

The 34-foot juvenile humpback whale was first reported floating off the coast on Sunday, May 26, near Nehalem Bay State Park. The whale carcass washed ashore on Monday, when the first samples were taken. A full autopsy, led by Portland State University, was performed Thursday. Staff from Oregon State Parks, Oregon Department of Fish and Wildlife, U.S. Fish and Wildlife Service, Cascadia Research Collective and Seaside Aquarium also participated in the necropsy.

Dead whales are often left to rot on the beach, as their carcasses provide food for eagles and other scavengers.

The public is asked to avoid the area where the whale stranded to avoid further disturbing the endangered Western Snowy Plovers which nest nearby. Dogs and bicycles are prohibited in the area, which is a more remote part of the national park.

To report a dead, injured or stranded marine mammal along the West Coast, the public can call the West Coast Region Stranding Hotline at 1-866-767-6114.

–Samantha Swindler covers features for The Oregonian/OregonLive and This is Oregon. Contact her at [email protected].

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