It typically would not be whale-watching season yet in San Francisco Bay, but a few gray whales, possibly due to changes in their feeding grounds up north, are making early stops in the Bay.

Last year saw a large number of gray whale deaths around the Bay Area, prompting concern that there could be another large die-off event on the horizon like one that occurred between 2019 and 2023. But nearly half of these deaths, at least locally, are caused by vessel strikes, which is why marine biologists are trying to keep track of the whales' behavior and where they tend to gather in and around the Bay.

On January 18, Marine Mammal Center field researcher Bill Keener heard of a gray whale sighting off the western edge of Richmond, via a ferry captain. Three days later, on January 21, Keener spotted the whale himself and photographed it, as he tells SFGate this week.

That was followed by two other whale sightings in other locations in the Bay during the month of January, and on Monday, Keener tells SFGate he spotted the same whale from mid-January — identified by a unique mottling pattern on its back — along with a second whale. And he now believes that both whales have likely been hanging around in the Bay the entire time, several weeks or more.

Keener says that he would usually not expect to see whales here until mid-February, as they may make pitstops to rest or feed in the Bay on their way north from their wintertime breeding grounds off Mexico to their summertime feeding grounds around Alaska.

Experts believe that the whales have been adapting to changing conditions in their habitats, and in the amount of available food where they usually migrate to in Alaskan waters. Some gray whales who have become familiar with the Bay may remember it as a place to feed, and word has gotten out, so to speak, to other whales in the process.

And hunger may be the thing that is driving the early migration. The die-off that was seen a few years ago was characterized by a number of sightings of malnurished whales — with their telltale scapulas showing on their backs.

Gray whales are known to be opportunistic eaters, and they are likely feeding on small crustaceans that can be found in the mud of the Bay and the Delta. And Keener tells SFGate that biologists at the Marine Mammal Center are working to figure out how much time the whales are spending in the Bay, and where they are spending time specifically — also, do they leave the Bay at night and come back? This information can then be relayed to ferry captains and ships coming into and out of port, in order to hopefully avoid more whale deaths from ship strikes.

The center is now working with the San Francisco Harbor Safety Committee’s Marine Mammal Subcommittee to develop Whale Smart, an education and training program for boat operators, with the aim of increasing whale safety.

Humpback whales, meanwhile, who dine on a more specific diet of plankton, anchovies, and small crustaceans, and this larger species of whale was a rare sight in the Bay up until the last decade — the reason likely being that they are chasing schools of anchovies, or seeking extra meals on their journeys north.

This is reportedly the earliest known set of sightings of gray whales in the Bay since the Marine Mammal Center began tracking them.

Previously: This Year Has Seen the Largest Number of Dead Gray Whales In the San Francisco Bay In 25 Years

Photo via Marine Mammal Center/Facebook