An entangled humpback whale that stranded near Yachats in November 2025 had chronic diseases in multiple organ systems that likely contributed to the stranding, a final necropsy report concluded.

The whale’s empty stomach and intestine also indicated that it had not eaten for weeks, leaving the whale with minimal fat stores, according to the report, by the Oregon Veterinary Diagnostic Laboratory at the Gary R. Carlson, MD, College of Veterinary Medicine at Oregon State University.

On Nov. 15, 2025, the young male whale was stranded on a beach north of Yachats, on the central Oregon Coast. It was euthanized Nov. 17 after attempts to return it to the ocean were unsuccessful.

The whale was entangled in fishing gear leftover from the 2023-24 commercial Dungeness crab season.

In February 2026, the Oregon Fish and Wildlife Commission voted to deny a petition to modify commercial crabbing rules to reduce the risk of whale entanglement, although it urged the state agency to continue its current efforts to reduce the number of whales getting caught in fishing lines.

The failed rescue attempt was heartbreaking for dozens of volunteers and the thousands of members of the public who spent a few days following along, hoping the whale would make it back to open water.

The laboratory’s examination found evidence of spinal cord disease, likely caused by an infection, according to the report.

The whale’s intestine and colon had signs of severe widespread inflammatory disease, likely the result of intestinal parasites.

The whale, which was about 1 to 2 years old, also had evidence of chronic congestive heart failure as well as acute heart failure resulting from the stress related to the stranding.

“When I look at all the results in the context of what we know about the whale, there are many signs it was having problems long before the stranding,” said Dr. Kurt Williams, director of the laboratory and lead pathologist on the case. “My interpretation of events is that the animal’s pre-existing disease challenges contributed to the whale’s entanglement and then to the live stranding.”

Williams reviewed the findings with marine mammal pathologists and scientists from around the world before finalizing the report.

“We hope the findings from this case expand our understanding of whale diseases and spur future investigations to understand and improve the health of whales and the oceans around the globe,” the report reads.

The Oregon Marine Mammal Stranding Network, coordinated by Oregon State University’s Marine Mammal Institute in Newport, responded to the stranding in coordination with other partners.

The Oregon program is part of the West Coast Marine Mammal Stranding Network and responds to strandings on the central and southern Oregon Coast.

Tracy Loew covers the environment at the Statesman Journal. Send comments, questions and tips: tloew@statesmanjournal.com or 503-399-6779. Follow her on X at @Tracy_Loew