Apr 092017

Sea Lions at Pacific Marine Mammal Center, Orange County

This is the second part of a two-part series about the recent unusual mortality events of California sea lion (Zalophus californianus) pups. The first article investigated the reasons why thousands of emaciated pups have been stranded on California beaches. This article highlights the work of nonprofit organizations dedicated to rescuing and rehabilitating them.


A network of rehabilitation centers take in sick and injured marine mammals along California’s coast, and each center has their own jurisdiction: Sea World, serving the San Diego area; Marine Mammal Care Pacific Marine Mammal Center, Orange County; Marine Mammal Care Center Los Angeles, Los Angeles and Long Beach; California Wildlife Center, Malibu; Channel Islands Marine Wildlife Institute, Santa Barbara and Ventura Counties; The Marine Mammal Center, San Luis Obispo through Mendocino counties; and Northcoast Marine Mammal Center, Humboldt and Del Norte Counties.

All centers handles their own rescues except for Marine Mammal Care Center Los Angeles (MMCC). Along with local Animal Control agencies, MMCC relies on Peter Wallerstein, the director and founder of Marine Animal Rescue, which is an organization entirely devoted to the rescue of marine mammals. Their authorized territory extends as far south as Long Beach, west to Catalina Island, and north to Pacific Palisades. Of the 4500 marine mammals they’ve rescued since 1985, 90 to 95 percent are California sea lions. Why so many? One reason may be sheer numbers: Compared to the 300,000 sea lions in California, there are just 39,000 harbor seals— approximately the same ratio as the strandings. Wallerstein estimated that of the 395 rescues they’ve done this year, 30 to 40 were elephant seals, followed by a few harbor seals, fur seals, dolphins, and sea turtles.

The organization’s busiest time of the year is from January to June, when starving sea lion pups lose their fat and become stranded on the beach. In an ominous Facebook post on November 4, 2016, they showed two pups rescued within the last 24 hours and the caption: “Starting early this year.”

Because upper water fish are depleted due to the collapse of the food chain, nursing mothers are forced to dive much deeper than usual. While their pups are small and unhealthy, at least they are alive. The reasons being fat- and calorie-poor fish such as short belly rockfish are generally found deeper in the water column than the fat- and calorie-rich fish like anchovies, sardines, and mackerel.

Peter Wallerstein of Marine Animal Rescue

Since the public plays a big part in rescues of not just stranded sea lions but entangled or beached whales, dolphins, seals, and even sea birds, Peter Wallerstein offered some guidelines for beach-goers who spot a sea lion or any marine mammal in need of assistance.

The first thing to do, he said, is call the Marine Animal Rescue on their 24-hour, toll-free hotline at 1 (800) 39-WHALE anytime day or night, 365 days a year. I told Wallerstein that I had called the center in Malibu two different times, and each time they said they didn’t have enough room. The second time they came and posted signs warning the public to stay away, and then left.

“We try to bring them in even if they don’t have a place for them,” Wallerstein replied. “We’ll bring them to another quiet beach where they can be left alone, and then we’ll keep an eye on them. What’s helpful for that is when we do relocate it, we tag it, and if that animal comes back on the beach, that’s a re-strand and that gives us more power to try to force the center’s hand.”

I found out later that the California Wildlife Center can only take up to 25 sea lion pups, so the response you get depends on where you happen to be and of course, the number of stranded pups there are.

If you spot one and call the nearest center, Wallerstein asked that you stay in the area and maintain contact by phone with the rescuers. “It’s pretty difficult searching both sides of a crowded jetty a quarter mile long to find an animal,” he said.

But keep your distance. “Not only are they federally protected animals, they also bite ten times harder than a dog,” he said. “If they have domoic acid (a neurotoxin that causes amnesic shellfish poisoning), they might have seizures on the beach, or chase lifeguards and trucks.”

If they’re on land, don’t try to get them back to the water. “Once you bring it back into the water, it’s almost a one hundred percent chance they’re going to die,” he said. “If they’re on land, we’re going to come get them and we’re going to bring them to the rehab center. If they go back in the water, then they have absolutely no hope.”

On the other hand, “If they’re trying to get back to the water, never cut off their path. Do not pull it into the water. If it’s weak and emaciated, it won’t survive.”

Don’t feed them. “About a month and a half ago, we found one guy spoon feeding a sea lion,” he said. “Luckily the animal was hypothermic because as soon as it warmed up, it got extremely aggressive. And you don’t want to give sea lion pups that are starving food right away. They need to be hydrated first. You can tell if a sea lion is hydrated by their eyes – if they’re runny, they’re hydrated. You can’t tell if they malnourished because they may be bloated and look fine to you, but that might be a belly full of parasites.” Sea lions are like fish in that they get their fresh water from the food they eat, so the starving pups are also dehydrated. When they’re transporting a pup, they surprisingly give them a dog bowl filled with freshwater, which can determine if they live or die. But they don’t give them food.


Mitchell Fong of The Marine Mammal Center

Mitchell Fong, a volunteer with the Marine Mammal Center in Northern California for the past thirteen years, explained that some of the emaciated pups are missing half their normal weight or more. As with humans, when pups are that malnourished, their digestive system can shut down making it impossible for them to digest food. “We often don’t even offer fish initially,” Fong said. “What we’re doing is while we’re tube feeding them, we’re checking to make sure that the animal is truly digesting the food; so if liquid starts coming out of the tube and we see its undigested formula, we know that their stomach is not able to digest the last meal we gave them.”

When starving animals arrive at their facilities, they are often given electrolytes for their first few feedings to help hydrate them. The most severely emaciated sea lions can have the longest progression toward fish—which could include first electrolytes, then Emeraid, a formula containing amino acids, protein, vitamins, minerals, and water. The next step is fish smoothies without salmon oil, then fish smoothies with salmon oil, then whole fish. The fish they use is sustainably harvested herring.

Since I live in Southern California, I visited the Pacific Marine Mammal Center (PMMC) in Orange County in early September to take a look at their facility. Established in 1971, this was the first rehabilitation center for marine mammals in California. They’re also one of the smaller ones and hold up to 135 pups comfortably. They have just thirteen paid staff (some are part-time), but 188 volunteers.

As soon as the patients arrive, they’re weighed. That helps the animal care and veterinarian staff determine medication as well as food intake, since sea lions need to consume up to ten percent of their body weight each day. A physical exam follows. Critical care patients stay in one of two heated pens — where even the floors are heated and blankets are provided.

Michele Hunter & Wendy Leeds of PMMC with Mary Ann Wilson

“When these guys come in, they’re emaciated, they have no fat layer,” said Lead Rescue Coordinator Wendy Leeds, who has worked for the center since 1996. “It’s the fat that’s keeping them warm. So any food that we actually give them, they burn off all those calories just trying to stay warm.”

Procedures are done in the lab, which houses an x-ray machines, a portable ultrasound machine, and an infrared camera that allows them to see deeper abscesses. Emaciated animals are hydrated via subcutaneous injection (subq for short) in which electrolytes are injected right underneath a layer of skin, rather than intravenously, to hydrate them. Depending on the situation, they are also tube fed: While the animal is restrained, a biter is placed inside its mouth, and the tube goes through the biter and then down into its stomach. This way staff can pour or push the formula into its belly, starting them with what they call Formula A, a combination of unflavored Pedialyte, Karo syrup and Nutri-Cal.

Formula B consists of fish added to electrolytes. Each pup has their own individualized formula and the amount of fish added depends on where the pup is at in its recovery process. By the time a pup can handle medium-thick formula, they’re weaned to fish. They start with capelin, a small and lean forage fish which is neither oily not fatty, followed by herring, which is a lot more oily and fatty. It’s the herring that’s bulks them up. Michele Hunter, the director of animal care who has worked there since 1989, said, “In our busy season we go through 800 pounds of fish a day, yeah and it’s roughly a dollar a pound so that’s over eight hundred dollars we’re going through in fish a day.” But, she said, “We always want the highest quality of fish for these animals, because they’re sick animals.”

As they get healthier, the pups are moved to different pens. Each pen has heated floors and can be closed if it gets too cold and windy. The animals that can eat but are still pretty thin are placed in pens with no access to a pool, though they can be brought to a pool on an individual basis. They start eating from bowls of fish. If two animals start eating at the same pace, a shallow pool is placed in the pen and fish are added. It’s a good sign if they start competing together, because ultimately they have to compete for their fish. The goal is for them to graduate to bigger pools with five or ten other animals, throw all their fish in there and let them swim around and compete for fish. If they continue to steadily gain weight, they’re likely to be successful out in the wild.

California sea lions stay with their mothers from six months to a year before they’re weaned. They learn everything from them, including social cues and how to swim. Before bringing in a newborn pup, PMMC staff make sure the mother has not left it on the beach to go out and forage. Because most newborns need to be hand–reared, they come to depend on human interaction and bond with their caregivers who guide them and even teach them to swim. They will not be successful out in the wild, so they are placed in a zoo or aquarium.

The rest are kept wild; staff members and volunteers don’t talk to them, and any kind of interaction is kept to a minimum. The majority of pups are born mid-June, and since the rescues start around January or February, they are already weaned and have eaten fish. Unless the pup has an injury that will prevent them from being release, their chances of being returned to the wild are high.

Katie © The Marine Mammal Center

Case Study: Katie

Katie was spotted on June 21, 2016 at Pirate’s Cove, a beach in San Luis Obispo County. A male sea lion pup, he was named by his rescuer who at the time didn’t know his gender. Katie suffered from ataxia (lack of muscle coordination), a swollen jaw, an open wound on his chin, and malnutrition. His body weight was low but not terribly low with a body weight of around 20 kilograms (44 lbs.).

The Marine Mammal Center, which serves San Luis Obispo through Mendocino counties, has full-service veterinary hospital is in Sausalito, but they also have field offices in San Luis Obispo, Monterey, and Mendocino counties. Katie was brought to the San Louis Obispo office, where they injected subq fluids.

At the same time, they tube-fed him fish mash. They figured he could digest protein since he was not severely emaciated, and his swollen jaw and wound most likely inhibited him from eating fish. They also had to decide whether he could make the four and a half hour drive to their hospital in Sausalito. Based on their observations, they took him first to their office in Monterey Bay and obtained a fecal sample, which allows them to look for things like parasites and diseases.

The next day they transported Katie to the hospital in Sausalito, where the veterinarian staff examined the wound to see what caused it and if the wound itself was causing other problems. To examine him for structural damage, they anesthetized him and did an x-ray. Luckily there wasn’t any.  They put him on antibiotics and pain medication for his swollen jaw and chin wound. While in Sausalito the ataxia cleared up and Katie became quite active. Wong surmised that the wobbling that was initially observed may have been due to either his injury or hunger.

The facility in Sausalito, in contrast to the one in San Luis Obispo, has some deep pools of water so sea lions can swim and go after the fish, rather than eating the fish in small, shallow pools of water. Soon after getting there, they were able to transfer Katie from being tube-fed to eating fish. By the time he was released about a month later, his weight was 37.5 kg – close to double his weight when he was admitted.

Back to the Ocean!


In July 2016, I was fortunate to see Katie and three other rehabilitated sea lions released by the Marine Mammal Center in Morro Bay. When they were let out of their individual cages, they touched noses and waddled to the ocean, as volunteers held boards and made a path for them. As soon as they hit water, one of them jumped up and immediately caught a fish. I was moved to tears.


Originally published in Catalina Marine Society’s OceanBights, p. 9


Mitchell Fong, volunteer with the Marine Mammal Center, Interview July 26, 2016

Peter Wallerstein, director and founder of Marine Animal Rescue, Presentation at Eco Dive Center in Culver City, August 16, 2016

Michele Hunter, director of animal care & Wendy Leeds, lead rescue coordinator; Pacific Marine Mammal Center, Interview September 4, 2016



Sea Lions at Pacific Marine Mammal Center, Orange County: Gordon Kelly

Peter Wallerstein of Marine Animal Rescue: Mary Ann Wilson

Mitchell Fong of The Marine Mammal Center: Mary Ann Wilson

Michele Hunter & Wendy Leeds of PMMC with Mary Ann Wilson: Gordon Kelly

Katie: © The Marine Mammal Center

Back to the Ocean: Mary Ann Wilson




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