BOLINAS, California (KTVU/BCN) - By Bay City News Service
A fin whale found dead in Bolinas this week died of blunt force trauma from a vessel collision, according to The Marine Mammal Center.
14 scientists performed a necropsy on the carcass of the 58-foot female fin whale that washed ashore between Brighton and Agate beaches. It was reported to the center on Tuesday.
It was the third dead whale in the span of less than a week to have washed ashore in the Bay Area.
"To have a third whale wash ashore here in the San Francisco Bay Area as a result of negative human interaction is a really unfortunate event," says Barbie Halaska, a researcher at The Marine Mammal Center. "Detailing the extent of the injuries to the whale through a necropsy allows us to see the impact that human activity has on marine wildlife and help us find solutions to prevent these incidents in the future."
Early in the necropsy, scientists discovered multiple broken ribs and severe tissues hemorrhaging, according to the Center. Upon closer look they discovered its skull was fractured and she had a fractured cervical vertebrae.
The whale was stranded a half-mile from shore at the southern end of Duxberry Reef, and scientists from the Marine Mammal Center and California Academy of Sciences initially were on the scene Wednesday afternoon to make preliminary observations.
Extra precautions were taken in response to this latest stranding because of the Duxberry Reef State Marine Conservation Area's status as a highly protected resource area under state and federal law, according to center officials.
Dr. Shawn Johnson, director of veterinary science at the Marine Mammal Center, said the death of a second endangered fin whale in a week is incredibly unfortunate.
A fin whale found offshore of Alameda County last Friday died due to a vessel collision, center officials said. A necropsy revealed fractures and dislocated vertebrae surrounded by massive hemorrhaging on both sides of the 45-foot juvenile female whale.
A 36-foot adult female gray whale carcass that washed ashore at Tennessee Valley Beach in Marin County also last Friday died due to severe entanglement.
The necropsy revealed linear lesions looped around the back of the neck and along both front flippers.
The injuries are consistent with an entanglement.
Scientists also found two lacerations on the whale's right side with multiple skull fractures consistent with a shop's propeller. Those injuries likely were suffered after the whale's death, center officials said.
Ship strikes and entanglement in fishing gear are the leading causes of whale mortality. The number of ship strikes likely is underreported because the ship's crew may be unaware a strike occurred, Marine Mammal Center officials said.
The fin whale in Bolinas will be left at the site of the necropsy where it will decompose naturally.