Starting in 2018, gray whales began regularly stopping in California’s San Francisco Bay, where they are vulnerable to ship strikes in one of the busiest ports in the United States. In response, researchers have deployed a monitoring network of thermal cameras and AI software to alert ships when whales are present in the bay to help them avoid whale collisions.
Gray whales (Eschrichtius robustus) have one of the longest migrations of any mammal species, roughly 19,000 kilometers (12,000 miles) from their feeding grounds in Alaska to their breeding grounds in Mexico, and back again. Climate change is making their feeding grounds in Alaska less productive, leaving the whales hungry as they head south to breed. Scientists believe that’s why gray whales have started stopping in San Francisco Bay to eat along their migration route. But the new pit stop brings whales into busy shipping zones, where more than 20 were killed by ship collisions in 2025, according to a news release.
Whale biologists at the Benioff Ocean Science Lab, WhaleSpotter, and the Marine Mammal Center have developed thermal cameras that can detect the heat signature of whale spouts and bodies when the whales surface.
“Next a trained human confirms the detection and will help classify the species when possible,” Rachel Rhodes, a project scientist with the Benioff Ocean Science Lab told Mongabay in an email. Then the information is, “posted publicly on [the] Whale Safe website, which is accessed by mariners in the Bay Area including Vessel Traffic Service and ferry operators who can then use this information to slow down or alter course if they are near a recent whale detection,” Rhodes said.
The researchers currently have two thermal cameras set up in San Francisco Bay. One is mounted on a Coast Guard tower on Angel Island in the middle of the bay. The other is on a ferry with a route that passes through a known hotspot for gray whales.
Rhodes said that the researchers’ long-term vision is a network of thermal cameras mounted on bridges, ferries and other Bay Area infrastructure to monitor the entire bay. She said thermal cameras with AI detection systems run 24 hours a day, unlike human whale spotters.
Before scaling up the pilot project, the team plans to spend the next two seasons working with “Bay Area stakeholders to ensure the data from these systems is being shared in a way that meets their needs and is giving them all the insight they need to avoid collisions with whales,” Rhodes said.
The whale detection project is getting attention from the California State Legislature. State representative Sam Liccardo introduced a bill to create a “whale desk [that] will protect these magnificent creatures and help mariners avoid costly, harrowing collisions,” Liccardo said in a statement.
Banner image: A gray whale in San Francisco Bay. Image courtesy of Darrin Allen © The Marine Mammal Center, NOAA Permit #26532
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