The San Francisco Bay, known for the Golden Gate and its intense port activity, has become an unexpected meeting point for the Eastern North Pacific gray whales. Since 2018, these whales have started to stop in the bay during their annual migration to Baja California and the Arctic, a behavior that was not previously recorded.
In 2025, a record of 21 dead whales was counted in the bay, and so far in 2026, seven have already been recorded. The situation worries scientists and residents, who observe the animals thinner than normal and showing signs of malnutrition.
Migration and Lack of Food
Gray whales undertake the longest migration of any mammal, traveling between 15,000 and 20,000 km each year. However, the decrease in prey in the Arctic seems to be pushing them towards the bay in search of food. Many arrive without the necessary energy reserves to complete the journey.
According to researcher Josephine Slaathaug, author of a study published in Frontiers in Marine Science, “hunger may be driving them to the bay.” The problem is that this new habitat also exposes them to additional risks.
Mortality and Collisions with Vessels
Slaathaug’s study revealed that nearly one-fifth of the whales entering the bay die there, mainly due to collisions with ships. The congestion of the bay, with large container ships, ferries, and recreational boats, increases the likelihood of accidents.
The U.S. Coast Guard is working with researchers and shipping companies to reduce vessel speeds, train captains, and establish surveillance systems, including infrared cameras to detect whales in high-traffic areas.
Worrying Signs
Sightings and strandings began earlier than usual in 2026, with two cases in January, when the peak usually occurs in April. Additionally, scientists have recorded a very low number of calves, indicating a low birth rate and a population that is not recovering as in previous times.
The National Oceanic and Atmospheric Administration (NOAA) reported that the gray whale population decreased from 27,000 in 2016 to 12,500 in 2025, describing the situation as an “unusual mortality event”.
A Ray of Hope
Despite the crisis, researchers like Michelle Barbieri Lino remind us that gray whales already experienced a remarkable recovery when commercial whaling was banned in the 1970s. If protective measures are implemented in the San Francisco Bay, this space could become a new safe feeding stop, helping the whales complete their migration and thrive again.
The mortality of gray whales in the San Francisco Bay reflects the interaction between climate change, human pressure, and food loss. The situation is critical, but it also offers a unique opportunity: protecting this new habitat could be key to the survival of a species that symbolizes both the fragility and resilience of the oceans.
