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The southern sea otter population has grown from just 50 otters to about 3,000.

SUZI ESZTERHAS/NATUREPL

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We're Still Here!

How California sea otters are inching back from a brush with extinction

JIM MCMAHON/MAPMAN®

This past July, an urgent call came in to the Marine Mammal Center in Sausalito, California. A young southern sea otter had washed up on the beach at nearby Half Moon Bay, and he didn’t look good. When rescuers arrived, the otter was starving, weak, and disoriented. They rushed him to the Marine Mammal Center to try to save his life.

Rescuers nicknamed the otter Yankee Doodle. He’s just one of 350 otters the center has rescued since it opened in 1975. These efforts, along with laws that protect otters, are helping the animals come back from the brink of extinction. A century ago, just 50 of the otters were left in the wild. Today, there are about 3,000. Scientists hope that someday there will be thousands more. 

A call came in this past July to the Marine Mammal Center. It’s in Sausalito, California. A young southern sea otter had washed up on a beach nearby. The beach was at Half Moon Bay. The otter didn’t look good. Rescuers arrived. The otter was hungry, weak, and confused. The rescuers rushed the otter to the Marine Mammal Center. They were going to try to save his life.

Rescuers named the otter Yankee Doodle. The center opened in 1975. Yankee Doodle is just one of 350 otters the center has rescued since then. The animals had once nearly become extinct. Just 50 of the otters were left in the wild 100 years ago. But laws protecting otters helped save them. The center’s rescue efforts helped too. There are about 3,000 otters today. Scientists hope someday there will be thousands more.

Ocean Living

Southern sea otters live along the coast of California. They swim among kelp forests—clusters of tall seaweed that are home to many animals and plants. The otters gather invertebrates such as sea urchins, clams, and mussels from the seafloor. Then they float at the surface and balance their meals on their bellies, using rocks to smash open the shells.

Otters play an important role in the kelp forest ecosystem (see Kelp Helpers). By eating the urchins that graze on kelp, otters help the kelp grow. “Sometimes we call otters ‘ocean gardeners,’” says Shawn Johnson. He’s a veterinarian at the Marine Mammal Center.

Three hundred years ago, as many as 20,000 sea otters paddled along the California coast. But in the 1700s, people began hunting them for their soft coats. This devastated the otter population. By the 1900s, so few otters were left that scientists thought they were extinct. Then locals discovered a small group of survivors.

Southern sea otters live along California’s coast. They swim in kelp forests. Many animals and plants call these groups of tall seaweed home. Otters gather invertebrates from the seafloor. They include sea urchins, clams, and mussels. Then the otters float at the surface. They balance shells on their bellies. They use rocks to smash open the shells and get to their meals.

Otters play a big role in the kelp forest ecosystem (see Kelp Helpers). They help kelp grow. That’s because they eat the urchins that graze on it. “Sometimes we call otters ‘ocean gardeners,’” says Shawn Johnson. He’s a veterinarian. He works at the Marine Mammal Center.

As many as 20,000 sea otters swam along California’s coast 300 years ago. In the 1700s, people began hunting them for their soft coats. This caused otter numbers to drop. Few otters were left by the 1900s. So few were left, scientists thought the animals had become extinct. Then locals found a small group of otters. They were still alive.

Bouncing Back

Starting in 1911, people passed laws that made it illegal to hunt sea otters. They also protected some areas where otters live. Later, organizations like the Marine Mammal Center began to rescue stranded otters. They nurse the animals back to health and release them into the wild.

These efforts have helped the otter population start to recover. But the animals still face many challenges. People live along the coast and eat the shellfish the otters need. Ships can leak oil and other pollutants into the water. Fertilizer from nearby farms can wash into the ocean and make otters sick.  

People starting passed laws to help otters in 1911. The laws made it illegal to hunt sea otters. They also protected some areas where otters live. Later, groups like the Marine Mammal Center were created. They began to rescue hurt otters. These groups nurse them back to health. Then they release them into the wild.

These efforts have helped boost otter numbers. But the animals still face many threats. People along the coast eat the shellfish that otters need. Ships can leak oil into the water. They leak other pollutants too. Fertilizer from nearby farms can wash into the ocean. It can make otters sick.

©The Marine Mammal Center/USFWS

A veterinarian checks the eyes of Yankee Doodle, a rescued sea otter.

That’s what happened to Yankee Doodle. Fertilizer in the water had temporarily caused plant-like organisms called algae to grow out of control. The algae made a toxin called domoic (duh-MOH-ik) acid. As invertebrates ate the algae, the toxin built up in their bodies. The more toxic shellfish Yankee Doodle ate, the sicker he got.

Veterinarians knew the otter needed better food. “We put Yankee Doodle on a diet of restaurant-quality shrimp, clams, squid, and mussels,” says Johnson. Over the next few months, Yankee Doodle slowly regained his strength.

That’s what happened to Yankee Doodle. Fertilizer entered the water. It caused algae to grow out of control. Algae are plant-like creatures. They made a toxin called domoic (duh-MOH-ik) acid. Shellfish ate the algae. The toxin built up in the shellfish. Yankee Doodle ate the toxic shellfish. The more he ate, the sicker he got.

Veterinarians knew the otter needed better food. “We put Yankee Doodle on a diet of restaurant-quality shrimp, clams, squid, and mussels,” says Johnson. A few months passed. Yankee Doodle slowly got his strength back.

©The Marine Mammal Center/USFWS

Yankee Doodle plays with fake kelp at the Marine Mammal Center in California.

An Uncertain Future

Southern sea otters still live in only a small part of their former range. They swim along a stretch of the California coast just 483 kilometers (300 miles) long. On either end of this small area, great white sharks gather to hunt. Sharks don’t typically eat sea otters, but they sometimes mistake them for seals and attack. This keeps the otters from moving up or down the coast.

“If we can get otters outside of these hunting grounds, that could really help them,” says Karl Mayer. He’s a biologist who works with rescued otters at the Monterey Bay Aquarium in California. Scientists there want to start releasing otters in new areas beyond the shark feeding grounds. From there, they hope, the otters could spread farther along the coast.

For now, rescuers are sticking to safe spots. On October 24, scientists carried a crate to the beach at Half Moon Bay and opened the door. Yankee Doodle waddled out, then dove into the water. Before he swam away, the otter lifted a fuzzy paw toward the people on shore. To some, it almost looked like he was waving goodbye.

Southern sea otters still live in a small part of their former range. They swim along a small stretch of the California coast. It’s just 483 kilometers (300 miles) long. Great white sharks gather to hunt on either end of this area. Sharks don’t usually eat sea otters. But they sometimes mistake them for seals and attack. This keeps the otters from moving up or down the coast.

“If we can get otters outside of these hunting grounds, that could really help them,” says Karl Mayer. He’s a biologist. He works with rescued otters at the Monterey Bay Aquarium in California. Scientists there want to start releasing otters beyond shark feeding grounds. They hope the otters could spread farther along the coast from there.

Rescuers are sticking to safe spots for now. Scientists carried a crate to Half Moon Bay on October 24. They opened the door. Yankee Doodle waddled out. Then he dove into the water. The otter lifted a fuzzy paw toward the people on shore. It almost looked like he was waving goodbye to some. Then he swam away.

©The Marine Mammal Center/USFWS

Yankee Doodle was released on the same beach where he’d been found.

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