The fluke of a humpback whale is seen as the whale swims in a lagoon on June 05, 2019 in Alameda. (Justin Sullivan/Getty Images)
A humpback whale that had been circling the waters near Alameda's shoreline for more than two weeks has apparently moved on in search of more expansive (and presumably affordable) real estate.
The adult female whale, which was affectionately named "Allie" by adoring onlookers who lined the shore for days to get a rare closeup glimpse of the animal breaching or spouting, was last seen on Saturday afternoon at the main opening of the breakwater closer to the open bay, said Bill Keener, a researcher with The Marine Mammal Center.
"We assume the whale is either in the bay or heading out towards the open ocean near the Golden Gate," Keener said. "But the whale’s location is unknown at this time. We don't know what prompted it to leave, but it's possible that it finally oriented itself, and had rested sufficiently in the protected waters of Alameda to attempt travel out into the bay and beyond."
The Marin Headlands-based center had been monitoring the whale since May 27, when it was first spotted in Alameda's protected Seaplane Lagoon in the shallow waters off the former Alameda Naval Air Station.
The baleen whale appeared to be noticeably underweight, with unhealthy skin, said Keener, who observed the animal closely by boat in the days after it was first spotted. He estimates that it's roughly 45 feet in length. It had no visible wounds or other indications of external injury or entanglement, he said.
Although humpback whales have been spotted at this time of year near the Golden Gate Bridge and Alcatraz, where they feed on anchovies, it's highly unusual for them to swim this far into shallow waters and remain for any length of time, Keener said. He speculated that the whale was in poor health and sought shelter in a calmer area to recover.
The whale then moved to an outer break wall close to where the USS Hornet is docked. Keener said it appeared more energetic there, increasingly breaching and tail slapping, even as it had not appeared to gain substantial weight.
"We don't know if was able to efficiently obtain food while in Alameda, but it had not appreciably gained weight judging from the thickness of its blubber layer," he said. "Its skin condition had not improved, either."
After the whale left the shallow waters near Alameda, Keener and his group searched the bay but found no signs of it. He's since alerted commercial vessels and the local boating community to be on the lookout. Mariners should be aware that a large whale may be moving around in the bay, and not come close to it, he said.
"Our hope is that we will be able to find the Alameda whale out in the ocean at some point in the future," he said.
A period of time spent in a sheltered area shouldn't compromise the whale's ability to return to the ocean, he added, as long as it's generally healthy enough to make the journey.
"We have seen other cetacean species spend a long time in the bay and successfully return to the ocean," he said.
In 1985, Humphrey, another humpback whale, remained in the bay and Sacramento River system for over 3 weeks, and was later found to be healthy in the ocean. And In 2015, a bottlenose dolphin spent a month in a quiet protected area of the bay near South San Francisco and later left on its own accord.
"We've had repeated sightings of that dolphin acting normally with groups of other bottlenose dolphins," Keener said.
It's unlikely that the whale’s distressed physical condition had any correlation to the slew of gray whale deaths that have been reported along the West Coast this year, prompting government officials last week to declare a wildlife emergency.
The two species of whales have completely different migration patterns, Keener said. While the gray whales' summer feeding grounds are in the Arctic, humpbacks typically migrate from Mexico to California, and as far north as Alaska, where food is abundant at this time of year.
"This is their feeding ground," Keener said. "There's plenty of food here. This is the feeding season when they're putting on weight."
The Marine Mammal Center is asking anyone who spots the whale to contact the US Coast Guard Vessel Traffic Service (marine radio channel 14) and center's hotline: 415-289-SEAL.
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