Thousands of emaciated seabirds are washing up on California beaches, killed by a marine heat wave that has disrupted the ocean food web. Scientists now warn that an approaching El Nino could push the die off to catastrophic levels.
A warming ocean starves the birds
The die off involves mostly common murres, black and white seabirds that resemble flying penguins. These birds rely on small fish like anchovies and sardines. When ocean temperatures rise, those fish move to deeper, cooler waters or become scarce. The murres cannot find enough food and starve.
Beach survey teams in San Diego found hundreds of dead or dying birds in May 2026. Many were severely underweight. The marine heat wave began in late 2025 and has persisted, creating a band of warm water along the California coast.
El Nino threatens to make things worse
Forecasters predict an El Nino pattern could develop in the Pacific later this year. El Nino typically brings even warmer ocean temperatures to the eastern Pacific. If that happens, the food shortage for seabirds could intensify.
Researchers from the California Current Ecosystem Monitoring Program have been tracking the event. They say the combination of an existing heat wave and a potential El Nino has no recent precedent. The last major seabird die off in California occurred during the 2014 2016 marine heat wave known as the Blob, which killed an estimated one million common murres.
Why local communities are paying attention
For people living along the California coast, seabirds are a visible sign of ocean health. When murres wash up dead on popular beaches like those near Scripps Pier, it draws public concern. Local wildlife rescue groups have been overwhelmed with calls about sick birds.
Fishermen also watch these events closely. The same warm water that pushes fish away from seabirds can shift commercially valuable species like squid and salmon. A prolonged heat wave affects both wildlife and livelihoods.
The die off is not just a California problem. Common murres range from Alaska to Baja California. What happens in one part of their range can signal broader changes in the Pacific Ocean.
A quiet warning from the sea
Marine heat waves are becoming more frequent and lasting longer. The current event off California is a reminder that ocean warming has immediate, visible consequences. Seabirds are dying because the water is too warm for their prey. If El Nino arrives as predicted, the death toll will almost certainly rise. No one knows how many birds the ocean can lose before the population cannot recover.
