Seals, sea lions beach in record numbers

It is the height of the marine mammal stranding season and on Friday, a fairly typical day, Malibu’s Wildlife Emergency Response co-directors Rebecca Dmytryk and Aaron Frank respond to a call on Malibu Road for a shark that had beached itself.

When the volunteers arrived, it had returned to the sea but was swimming in circles just beyond the surf zone. Dmytryk is in contact with experts by cell phone. They say the shark has the best chance to survive if it stays in the sea, rather than being removed, and they don’t have a tank for it anyway. It is a thresher shark, about 6-8 feet long, with a long tail and red dorsal fin. If it beaches again and dies, Dmytryk says they would want to do a necropsy to find out what killed it.

A few hundred yards down the beach is an elephant seal pup basking quietly in the sun and flipping sand over its back. “It’s skinny, but for this year, it’s way better than most we see . . . maybe a little dehydrated,” says Frank, explaining that seals come up to rest on the beach naturally. “There was one two days ago that had a wound on its abdomen. It was about the same age and size as this one, but I can’t tell if it’s the same one unless it turns over.” He guesses its age at about 3 or 4 months.

“They are born in March or April, nurse for one month only, then are on their own,” he says. “El Nino has caused major changes in their food supply.”

Post-mortem studies are being done on sea lions this year because of the extraordinary numbers of deaths. “Marine mammals are sentinels for what’s happening. They’re our link to the ocean, at the top of the food chain,” Frank says.

Sea lions are opportunistic feeders, but seem to prefer squid and anchovies. “This year, it’s not clear what they’re feeding on,” Frank says. “Some are doing well, but we’re seeing at least two to three times as many dead as in ordinary years. Some are malnourished, but others appear well fed.”

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Some of the sea lions that beached in recent months had seizures, which Frank says could be caused by toxic pollution, mercury poisoning or algae blooms. “That’s why we’re studying tissue samples of their major organs. But we need some support for the studies. The necropsy lab results are sent to Maryland to the Armed Forces Institute for pathology and NMFS.” With some financial support, WER volunteers hope to be able to develop lab facilities here.

Residents are encouraged to call WER at 456-WILD to report beached marine mammals. By law, the animals cannot be moved or disturbed in any way before they have been observed for 48 hours. Some malnourished or injured pups are transported to facilities in San Pedro for treatment before they are released back into the sea. WER is also recruiting volunteers and providing training for rescue work.

13StarsManager
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The Malibu Times is the first newspaper in Malibu, serving the community since 1946.

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