Watsonville | Juvenile humpback whale found dead on Sunset State Beach
WATSONVILLE - A dead juvenile humpback whale was spotted on Sunset State Beach Friday. California State Parks buried the whale on the beach Sunday morning.
The whale was spotted on a stretch of beach known as Upper Sunset Beach. Staff from California State Parks contacted the Long Marine Lab Marine Mammal Stranding Network to report the stranding, said Scott Sipes, superintendent of park operations for the Santa Cruz district of California State Parks.
Members of the Long Marine Lab arrived at Sunset State Beach Saturday morning to examine the whale carcass and perform a necropsy, or animal autopsy. While the animal's cause of death is still under investigation, the lab was able to rule out a few causes, said Robin Dunkin, director of the Long Marine Lab Stranding Program. The whale seemed to be in good nutritional condition and didn't show any clear signs of fishing line entanglement or boat strikes.
Dunkin said that one of her top concerns is that the whale died of domoic acid poisoning. Domoic acid is a neurotoxin that can be produced in large amounts by harmful algal blooms. Dunkin said that the Monterey Bay has seen such blooms four years in a row.
As scientists continue to analyze the samples obtained during the necropsy this week, they will get a better idea of the whale's cause of death, and whether domoic acid could be the culprit.
Dunkin noted that whale deaths are a natural part of the ecosystem. Marine ecologists, including researchers at the Monterey Bay Aquarium Research Institute, have found flourishing ecosystems that develop around whale carcasses that fall to the sea floor.
"While we have concern around increasing numbers of whale deaths, the death itself is actually a really important part of the ecosystem," Dunkin said.
For that reason, Dunkin and the Long Marine Lab encourage towing whale carcasses off the beach into the ocean or letting the animals decompose on the beach. Sipes acknowledged that this is generally the preferred path, but said that safety considerations came first.
Concerned about increased shark activity due to the whale stranding, California State Parks moved to bury the whale on Sunset State Beach in the interest of public safety. Sunday morning, State Parks used heavy machinery to dig a deep hole on the beach and bury the whale, Sipes said.
The whale death at Sunset State Beach came just days after another juvenile humpback whale was found dead in Pacific Grove on Hopkins Marine Station beach, near Lovers Point. While whale strandings, especially for gray and humpback whales, are expected, Dunkin said, seeing two strandings within 10 miles in a short time frame is unusual.
Like the Sunset State Beach whale, the whale found in Pacific Grove showed no signs of vessel strikes and seemed to be in good nutritional condition.
The Long Marine Lab and other partners are hoping to tow the whale carcass in Pacific Grove, but oceanographic conditions have not yet allowed for such an operation. The whale is located on a sensitive beach that is often home to pupping harbor seals. Lovers Point is also a popular and well-known public beach, so it would be beneficial to get the carcass out of the way, Dunkin said.
The two Monterey Bay strandings come in the midst of a year of elevated whale mortality, according to a press release from the Long Marine Lab. Before the Pacific Grove and Sunset Beach sightings, 60 whales had been found stranded along the United States West Coast. These two findings bring the number up to 62.
Of the 62 whales stranded, 52 have been gray whales. Most of those have been in poor nutritional condition, according to the press release. Food availability has been scarce in the Arctic as climate conditions change. Some other whale deaths were caused by vessel strikes.
Sunset State Beach remains open to visitors and never closed as a result of the whale stranding. At this time, Lovers Point has been reopened with a beach advisory in effect. Dunkin said that people and pets are recommended to stay away from stranded whale carcasses, as they can carry disease. The heavy whales can also be unstable in the surf.
Responses to the stranded whales have been carried out by the Marine Mammal Stranding Networks at UC Santa Cruz's Long Marine laboratory and San Jose State's Moss Landing Marine Laboratory, in collaboration with partners including the city of Pacific Grove, Stanford University's Hopkins Marine Station and NOAA Fisheries.
The Long Marine Lab plans to study samples from both whales beyond simply finding their causes of death, Dunkin said.
"We've collected a lot of samples for other kinds of research projects," she said. "They're both contributing to greater knowledge about humpback whales, about whales in general."
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