The gray whales showing up in San Francisco Bay these days aren’t sightseeing. They’re hungry, stressed, and increasingly caught in one of the worst possible collision zones on the California coast—sandwiched between ferry routes, cargo ships, and shipping lanes that crisscross the choppy waters around Angel Island, Alcatraz, and Treasure Island.
And now, the bay has a technological answer: WhaleSpotter, an AI-powered detection network that launched this week to track whales around the clock using thermal cameras and computer vision. The system scans for whale blows and heat signatures up to 2 nautical miles away, feeding real-time alerts to ferries, vessel traffic controllers, and mariners through the Whale Safe website. It’s less“save the whales”and more“let’s stop killing them by accident.”
The urgency is real. Last year, 21 dead gray whales washed up in the Bay Area—the highest count in 25 years, according to The Marine Mammal Center. At least 40 percent were killed by ship strikes. This year, with just five months in the books, at least 10 more have died. And those numbers are almost certainly low; many carcasses sink or drift out to sea before anyone finds them. Researchers at the Benioff Ocean Science Laboratory, who spearheaded WhaleSpotter, reported that responders have literally run out of places to land dead whales.
So why are so many whales hanging out in the busiest shipping channel on the West Coast in the first place? Climate change, basically. Warming Arctic temperatures and shrinking sea ice are disrupting the food web that gray whales depend on during summer feeding months, according to a 2023 study published in Science. The result: malnourished whales starting a brutal 12,000-mile migration already at a disadvantage. Instead of pushing straight through to Arctic feeding grounds, more whales are now lingering in San Francisco Bay for days or even weeks, looking for food they’re not finding elsewhere.
The eastern North Pacific gray whale population has cratered from what used to be a conservation success story. Once removed from the Endangered Species Act in 1994 after rebounding from commercial whaling, the population has now halved in just 10 years. Roughly 13,000 remain. Thomas Hall, director of operations for San Francisco Bay Ferry, says the WhaleSpotter system will eventually allow his crews to adjust routes seasonally and avoid whale hotspots altogether. Rachel Rhodes, the project scientist who led the initiative at the Benioff lab, describes the new camera on Angel Island and an upcoming mobile unit aboard a ferry as a“moving data collection platform.”
The technology itself isn’t new—WhaleSpotter systems already operate on vessels and coastal towers in the U.S., Canada, and Australia. But San Francisco’s network is the first to directly link land-based and vessel-mounted detections with official mariner alerts, creating something close to real-time coordination between whales and the ships trying not to hit them. Douglas McCauley, director of the Benioff lab, said the first hours of testing produced so many detections that it“put me a little bit on edge.”But that flood of data is precisely the point. Unlike human observers, thermal cameras work through fog and darkness—both common conditions in the bay.
Meanwhile, humpback whales face a different threat along the coast: entanglement in Dungeness crab fishing gear. As warming ocean waters push krill, anchovies, and sardines closer to shore, humpbacks follow their prey directly into tens of thousands of vertical lines connecting traps to surface buoys. Curious by nature, humpbacks will scratch their backs on the gear; if a line wraps around their body, they breach and roll, tangling themselves further. Whales can drag heavy equipment for months, unable to feed or dive properly, which leads to starvation, infection, and drowning. Thirty-six whales were confirmed entangled off the West Coast in 2024—the highest number since 2018.
California just approved commercial use of ropeless pop-up crab fishing gear for the first time this spring. Instead of surface buoys, ropes and buoys sit on the seafloor until fishermen return and trigger an acoustic release to bring the gear up. It’s a compromise that lets fishermen keep harvesting while dramatically reducing whale risk. Caitlynn Birch, Pacific campaign manager for Oceana, says California has positioned itself as a national leader in whale-safe fishing tech—and hopes that model spreads to other fisheries along the West Coast and beyond.
The WhaleSpotter launch signals something bigger: California is betting on technology and adaptation to manage a crisis created by climate change. As warming oceans reshape migration patterns and push whales into human-dominated waters, the overlap between marine mammals, shipping, and fishing will only persist. Science-driven management and innovation aren’t just helpful anymore—they’re essential.
About the Author
Andrew Johnson
Andrew Johnson is a contributor to LocalBeat, covering local news and community stories.
