Gray whales: more deaths off Bay Area

Gray whales are showing up in San Francisco Bay more often. A lot of them are not making it back out. That is the immediate Bay Area story. But the bigger story starts thousands of miles north, in Arctic feeding grounds that seem to be getting less reliable for a species that depends on arriving there fat and leaving there fatter. ### What changed this spring? The Marine Mammal Center’s running 2026 tally shows 10 gray whale strandings from March 17 through April 26 in the broader Bay Area response zone, including animals found in San Francisco Bay, Pacifica, Bodega Bay, and Moss Beach. Several causes remain undetermined because some carcasses were inaccessible or too decomposed, but at least one death is listed as a suspected vessel strike and multiple others are still being evaluated for strike injuries. (marinemammalcenter.org) ### Why are scientists so alarmed? Because this is not just a random cluster of bad luck. A new Bay-focused study tracked 114 individual gray whales seen entering San Francisco Bay between 2018 and 2025 and matched that with necropsy records. At least 21 of those whales were later found dead. That gives a minimum mortality rate of 18% — basically, nearly 1 in 5 identified whales entering the Bay died there. (marinemammalcenter.org) Only four were seen in more than one year. ### Why are whales entering the Bay at all? That is the strange part. Gray whales usually migrate between Baja calving lagoons and Arctic feeding grounds, not into a crowded estuary full of ferries, cargo ships, and fog. Researchers think some whales are diverting into San Francisco Bay to forage because food conditions elsewhere are getting worse or less predictable. The Bay may look like a refuge. The catch is that it is also a shipping corridor with one narrow entrance at the Golden Gate. (frontiersin.org) ### So where does climate change fit in? Mostly upstream of the Bay story. NOAA’s 2025 update said the eastern North Pacific gray whale population had fallen to about 13,000 — the lowest since the 1970s — and calf production stayed extremely weak, with only about 85 calves counted in 2025. NOAA tied the 2019-2023 unusual mortality event to ecosystem changes in Arctic and Subarctic feeding grounds that reduced prey, increased malnutrition, and cut reproduction. (fisheries.noaa.gov) The inference Bay scientists are making is straightforward — stressed whales may be more likely to take risks, feed in odd places, or arrive in poorer condition. ### Is this only a Bay Area problem? No — and that is part of why the Bay deaths matter. In Washington, Cascadia Research said 9 gray whales had already stranded by April 12, 2026, the highest number that early in the year in its records. Several examined whales were malnourished, and researchers there also described live whales in poor condition using unusual habitat. That suggests the Bay is one piece of a coastwide stress signal, not an isolated local event. (fisheries.noaa.gov) ### What is killing the whales in the Bay? Boat strikes look like one major answer, but not the only one. The Bay study says many deaths were linked to vessel strikes, while some others were tied to starvation. That combination makes grim sense. A weakened whale is more likely to linger in dangerous places, and gray whales are hard to spot because they ride low in the water — especially in Bay fog. (cascadiaresearch.org) ### What are researchers trying to figure out now? They are trying to connect local deaths to global causes without oversimplifying the chain. A whale that dies near Alcatraz may have started getting into trouble months earlier in the Arctic food web. Scientists still do not have a single clean explanation for why Bay entries spiked again after a quieter 2024 season. But they are testing the same broad idea from multiple angles — prey shifts, nutritional stress, migration changes, and collision risk in crowded water. (frontiersin.org) ### Bottom line? The Bay Area is seeing the visible end of a much larger problem. Gray whales are not just dying near San Francisco. They may be rerouting their lives around an ocean that is getting harder to read. (fisheries.noaa.gov) (abc7news.com)