The federally endangered fin whale that died this week on Stinson Beach in front of curious onlookers could turn out to be a boon for scientists looking to glean new information about the species.
The 10-ton, 42-foot-long male whale, believed to be less than a year old, was alive, and thrashing in the surf when it was first spotted Monday morning. But within a couple of hours it died.
A team from the Marine Mammal Center in the Marin Headlands and California Academy of Sciences in San Francisco quickly went to work on the massive animal, performing a necropsy.
"It offered a very rare opportunity," said Moe Flannery, collections manager at the academy, who was on hand for the work.
Specifically, histology work -- the study of cells -- was something researchers focused on. Tissue samples were taken for study from the whale's heart, liver, lymph nodes and other organs, which all were intact.
Large whales typically die at sea and their carcasses usually are scavenged and sink to the ocean floor. If they do wash in with the tide the bodies are so badly decomposed nothing can be learned from what is left.
But the young whale at Stinson was in excellent condition, deepening the mystery of how exactly it died and why it ended up so far away from where it should have been. Fin whales forage along the continental shelf break and the outer continental shelf but may venture near shore at land promontories such as Point Reyes.
"We will learn more not only about this whale, but the species in general," Flannery said.
Performing a postmortem on a 22,000-pound mammal was not an easy task.
With the whale dead in the surf, Marine Mammal Center workers stuck a stake into the soft sand and tied a rope around the animal's peduncle -- the area from its dorsal fin to its tail -- to keep it from drifting out to sea.
As the tide rose, a chain was attached to the whale and a backhoe attempted to drag it into place for the examination, but the chain snapped. The piece of machinery's front loader was then used to push the animal into the correct positions.
The team then used knives to slice through the blubber and then muscle tissue. By the contents of its stomach, researchers believe the whale had been weaned and was no longer relying on its mother. But it is possible the young whale -- at less than a year old -- may have lost its way and headed to the beach's shallows in error, Flannery said. The necropsy revealed the whale had trauma to the sternum area and internal hemorrhaging around the heart. In addition, air was present in the subcutaneous tissue -- the area between the muscle and fat -- an indication of trauma. But there were no broken bones. A killer whale attack or a ship strike have been mentioned as possibilities, but a definitive cause has not been determined. It also could have been a victim of its own weight once it rested on solid ground.
"It is a difficult case," Flannery said. "There was nothing obvious. Because it was found alive you want to know why it died."
Those who came upon the scene Monday morning had hoped the whale would survive, but that was an unlikely scenario, said Dr. Shawn Johnson, director of veterinary science at the Marine Mammal Center.
"It's very stressful ... to turn up on the beach alive," he said.
The whale's remains were buried beneath several feet of sand at the beach. The skeleton may be retrieved by the Academy of Sciences at a later date.
"The whale will decompose naturally in the sand," Johnson said.
Since 1979, the Marine Mammal Center has responded to 31 cetacean strandings at Stinson, Seadrift, Steep Ravine and Red Rock beaches. Marin's currents tend to push a lot of material onto beaches, Flannery noted.
"And it happens that the beaches are accessible too," she said.
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