Beached Whale Was Ill Prior To Encounter With Crab Gear

Veterinarians and other experts conduct a necropsy on the stranded humpback whale near Yachats, Oregon. Credit: Oregon State University Marine Mammal Institute/Craig Hayslip

The entangled humpback whale that stranded near Yachats, Oregon, in November 2025 had several chronic diseases that likely contributed to the stranding. These are the results from the final necropsy report by the Oregon Veterinary Diagnostic Laboratory at the Gary R. Carlson, MD, College of Veterinary Medicine at Oregon State University.

“Significant chronic disease processes in multiple organ systems likely contributed to the stranding independent of entanglement,” the report said. The whale’s empty stomach and intestine also indicated that it likely had not eaten for weeks. That also left the whale with minimal fat stores, the necropsy found.

The laboratory’s examination of the male humpback whale found evidence of spinal cord disease likely caused by an infection, according to the report from Dr. Kurt Williams, director of the Laboratory and lead pathologist on the case. The whale’s intestine and colon had signs of severe widespread inflammatory disease, likely the result of intestinal parasites.

The whale, 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.

Responders would not have been aware of these underlying conditions when attempting a rescue. “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,” he said. “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 said. The Oregon Marine Mammal Stranding Network, coordinated by Oregon State University’s Marine Mammal Institute in Newport, Oregon, 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.

Gary Ripka president of the Oregon Coast Crabbing Association said they are continuing to work with ODFW to minimize whale entaglements in crabbing gear. He said they have been attending meeting with ODFW and the crab commission to find solutions to these issues. He added that 10-years ago scientists with NOAA reported that they were seeing whale populations increaseby 8.2%

Thiis means that whales would be at ocean capacity. This increase they reported was going to lead to a lack of food sources for the whales as their population would outnumber the amount of resources the ocean could provide, causing malnutrition. When whales are ill or injured they can drift toward shore and that is where they can come into contact with crabbing gear.