So far in 2025, Mexico’s Pacific coast has seen a troubling rise in gray whale deaths. According to Milenio News Agency, 91 dead whales have been recorded as of mid-May, surpassing the previous record of 88 in 2020 during an “Unusual Mortality Event.”
This ongoing phenomenon, which began in 2019, has alarmed scientists and environmentalists due to its serious impact on both the gray whale population and the broader marine ecosystem.
Dr. Jorge Urban, head of PRIMMA (Marine Mammal Research Program at the University of Baja California Sur), attributes the crisis to food scarcity in the whales’ Arctic feeding grounds. Melting sea ice driven by climate change has reduced the availability of algae that support the whales’ prey.
As a result, many whales arrive in Mexico in poor health, making them more vulnerable to disease, ship strikes, and predators like orcas. The La Niña phenomenon has worsened the situation by cooling Pacific waters, forcing whales to travel farther for food and expending even more energy.
Many of these whales die at sea, with their bodies never reaching the shore, suggesting the true death toll may be higher. The crisis affects not only adult whales but also reproduction. Only 69 births have been recorded this year, the lowest on record. Females that mated last year likely lacked the energy or resources to carry pregnancies to term, further hindering population recovery.
The location of whale carcasses also shows troubling changes. While most have historically washed up in Ojo de Liebre Lagoon, the main congregation site, this year’s strandings have extended farther south to Magdalena Bay, San Felipe, Guaymas, Mazatlán, Loreto, and La Paz. This shift may reflect altered migration routes due to the ongoing food search.
The “Unusual Mortality Event” was first declared in 2019 when 83 deaths were documented. The number peaked at 88 in 2020, then declined, reaching just 29 in 2024. However, with 91 deaths already reported in 2025, scientists now question whether the crisis ever truly ended.
PRIMMA estimates that the gray whale population has dropped sharply from about 24,000 in 2016 to roughly 14,000 by 2022, a 30% decrease. Although the species isn’t currently at risk of extinction thanks to its resilience, Dr. Urban argues its protection status under SEMARNAT (Mexico’s federal environmental agency) should be elevated from “special protection” to “threatened.”
Despite past recoveries gray whales have historically faced high mortality every 15 years. Future survival depends on effective conservation and climate action. The growing death toll on the Mexican coast highlights an urgent environmental crisis with long-term consequences for this iconic species and the ocean habitats it depends on.