A humpback whale seen diving and spouting in Southeast Alaska for nearly four decades was found floating dead in the ocean earlier this month, felled by an apparent ship strike, scientists said.
Known as Max, Aequorea or simply No. 539, the whale was known for frequenting Icy Strait as well as Glacier Bay, where she was first documented in 1975. She gave birth to five calves between 1982 and 2002, and has at least three grand-calves, according to a database of Southeast Alaska humpback whales.
On July 1, a charter operator spotted the whale's carcass floating in the ocean and reported it to the National Oceanic and Atmospheric Administration. NOAA officials located the carcass, the condition of which indicated the whale had only been dead a few days, and towed it to a shore in the upper Chatham Strait.
On Thursday, a team of nine people including a veterinary pathologist and marine mammal specialists reached the carcass for a necropsy.
"They saw an exposed jawbone and the fracture was immediately apparent," NOAA said in a news release.
The lead veterinarian, Kathy Burek of Alaska Veterinary Pathology Services, said in the release that the left mandible was fractured and the right mandible was "traumatically dislocated" from the whale's brain. The cause of death was determined to be a ship strike.
The scientists collected tissue and organ samples, including the contents of the whale's stomach. An analysis of the eye and ear plug will help determine her age, the release said.
"We appreciate everyone's involvement to make this necropsy happen," Aleria Jensen, NOAA Fisheries Alaska Region marine mammal stranding coordinator, said in the release. "It is a tragic event, but important to have such a clear cause of death to understand the factors impacting humpback whales."
With the humpback whale population recovering, the scientists said the death should serve as a reminder to ship captains to be watchful on the water and slow down when whales are in the area. Studies have shown slower speeds significantly reduce the chance of a lethal injury to whales.
NOAA's Office of Law Enforcement is in the process of investigating the death of No. 539. Anyone with information about the incident can call the office's hotline at (800) 853-1964.