Mysterious Sea Lion Stranding Continues

Scientists are stumped as to why hundreds of starved pups have been washing up on the California shore.

Written byBob Grant
| 1 min read

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A California sea lion pupWIKIMEDIA, ORBITGALAs of late last week there appears to be no end in sight to a steady stream of sea lion pups that have been washing up on the coast of California, suffering from starvation. And researchers are struggling to determine what’s causing the mass strandings. More than 1,000 pups had already been taken to marine mammal rehabilitation facilities in the state by Thursday (April 4), according to Wired Science.

The National Oceanic and Atmospheric Administration (NOAA) has declared it an “Unusual Mortality Event,” and teams of investigators are preparing to study the problem. Already, the event has produced more stranded sea lion pups than the yearly average.

Researchers will try to determine what exactly is causing the animals to starve, with the likely suspect being some environmental perturbation that is disturbing the sea lions’ food source, small fish that normally congregate offshore. Typically, warmer coastal waters will cause populations of anchovies and sardines to move or die off, but California waters have been cooler than average for a few years. But fish numbers have declined in recent years, and some scientists think that shifting ocean currents or other longer-term variations in atmospheric conditions could ...

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Meet the Author

  • From 2017 to 2022, Bob Grant was Editor in Chief of The Scientist, where he started in 2007 as a Staff Writer. Before joining the team, he worked as a reporter at Audubon and earned a master’s degree in science journalism from New York University. In his previous life, he pursued a career in science, getting a bachelor’s degree in wildlife biology from Montana State University and a master’s degree in marine biology from the College of Charleston in South Carolina. Bob edited Reading Frames and other sections of the magazine.

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