What Sea Lions Reveal About Ocean Health | The Pew Charitable Trusts

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Meet Gary. He’s a California sea lion who ended up at the world’s largest marine mammal hospital after being exposed to harmful marine algae. Gary needs care and nourishment before he can make his way back home to the ocean.

In Sausalito, California, the “After the Fact” team visited The Marine Mammal Center to see how they care for animals like Gary that are affected by harmful algal blooms (or “red tides”).

Experts at the center share how marine mammals such as seals and sea lions can give advance warnings about the health of the environment. Because the health of the ocean, wildlife, and humans are all interconnected, when marine mammals become sick due to ecosystem changes, that has ripple effects for humans too.

A group of sea lions lounge on the rocky coastline of a beach as the waves crash on the shore. — This fall, The Marine Mammal Center has been receiving more than 500 calls and reports per day about animals needing assistance as they deal with a serious outbreak of domoic acid toxicosis, which is a dangerous condition caused by a neurotoxin that is created by harmful marine algae.

A sea lion in a tank of water holds a fish in its mouth as a person in a hat and overalls crouches nearby, holding a fish. — Neurotoxins from harmful algae accumulate in small fish that marine mammals such as sea lions eat in large quantities, and they don’t drink water to flush it out of their systems. At The Marine Mammal Center, they rehabilitate marine mammals with fish, fluid, and medicine with the goal of releasing them back to the ocean.

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