Just as people have been reveling in the growing number of sea lions at Pier 39 in San Francisco, a different story is unfolding on the Central Coast, where a large number of dead sea lion pups are washing ashore.
Pupping season starts next month, but hundreds of sea lion pups washed up on an island on the Central Coast, appearing to have been miscarried.
Drone video footage taken over Ano Nuevo Island shows the dead sea lion pups. Researchers estimate there are nearly 300. In an average year, scientists count about 700 pups born with only one or two miscarried.
Researchers from UC Santa Cruz are studying the carcasses to determine a cause. One possibility is there’s just not enough food for a booming population. The scientists track the sea lions via satellite and find they’re going as far south as Baja California to feed.
"My best guess is that we're coming off of an El Niño event. That means that food links are down," said Daniel Costa, a UC Santa Cruz researcher. "There's less food, there's less fish in general. My best guess, and it's a guess, is that food availability is down. California sea population is at an extreme high, so they're already at a point where they're pretty much maxed out."
Meanwhile, since early May, there's been a spike in sea lions at Pier 39 in San Francisco, and biologists told NBC Bay Area it's due to the anchovies. There were more than 1,000 sea lions at the pier, the most seen in 15 years.
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