The San Francisco Bay has been hosting an influx of gray whales over the past couple weeks or so. One was found east of Angel Island State Park on April 2 and another was found off Fort Point Rock Beach close to the San Francisco end of the Golden Gate Bridge on April 4. On March 29, another dead whale was found floating dead near Alcatraz Island.
Since the whales started hanging out in the Bay, there have been multiple sightings and experts from the Marin Headlands-based Marine Mammal Center are advising boaters to be careful while out on the water because, while famously large, the animals are sometimes difficult to spot.
“There continues to be a significant number of gray whale sightings in San Francisco Bay as this species continues their northern migration to their Arctic feeding grounds,” said Kathi George, director of cetacean conservation biology at the center.
“With the bay serving as a shared space for commerce and increasing whale activity, it’s vital that all boaters, from large commercial vessels to sailboats, be whale-aware and if you see a blow, go slow,” George said.
“While this number of gray whales in San Francisco Bay is exciting to see, it does raise concerns for both human and whale safety,” said George after the body of the first whale was found. “Gray whales are difficult to see due to their low profile and coloration patterns that naturally blend into the bay. It’s important for all boaters to be extra vigilant and whale aware.”
It’s unclear what killed the whales. The adult male found near Angel Island was towed ashore with the help of the U.S. Army Corps of Engineers. A team of scientists from the Marine Mammal Center and the California Academy of Sciences were scheduled to perform a necropsy Friday to determine the cause of death.
The whale near Fort Point is stranded on a shallow rocky area that is currently inaccessible to boats, so scientists haven’t been able to determine its gender or collect tissue samples.
As for the dead whale first spotted on the morning of March 29, personnel from the center and the California Academy of Sciences boated out to take tissue samples, photos and tag it with a buoy.
By the next day, the whale had drifted under the Golden Gate Bridge, out of the bay and onto Black Sands Beach in the Golden Gate National Recreation Area on the Marin Headlands.
That’s where a team of scientists was able to conduct a necropsy on the 36-foot whale Monday, according to Marine Mammal Center officials.
There was no initial evidence of blunt force trauma from being hit by a boat, one of the top threats to gray whale safety.
Tests on the dead whale’s tissue samples to determine its cause of death can take several weeks to conduct.
People can report dead, injured or stranded marine mammals in the San Francisco Bay Area by calling the California Academy of Sciences at (415) 379-5381 for dead animals or the Marine Mammal Center at (415) 289-7325 for live animals.
People can also download a whale alert app at https://conserve.io/new-page.
This article was originally written by Kiley Russell for Bay City News.
