Big Things Come from Small Beginnings: The Mystery of the Sick Sea Lions
July 31, 2013
By Shari Sant Plummer, Mission Blue Board Director, President, Code Blue Foundation
On a cold, foggy morning along the Malibu coast, a small brown lump emerges from the sea and waddles ashore. I spot it from 100 yards away, but already my dog, Cooper, is at a full run toward the baby sea lion. I scream at him to stop, but it’s too late: The thin, frightened sea lion pup is heading back into the ocean. I finally catch up to Coop and pull him back, and we watch as the pup swims out through the waves. Though Cooper hadn’t touched him, the timid pup was easily threatened; animal lovers with cameras approaching other pups have been met with the same result. They don’t know that the cute but frighteningly thin sea lion pups are coming ashore because they are starving to death. But I do. We’ve rescued dozens of pups off our beach in the last month. I curse at myself for not having Cooper on a leash. I hope this one makes it safely back to shore—or, better yet, gets lucky and finds food.
Our Code Blue Foundation and many others contributed to fund an additional rescue facility at the California Wildlife Center. This spring the rescue facilities up and down the coast of California were filled to capacity with sea lions, elephant seals, and harbor seals. More than 1,300 pups came ashore this year desperate for help, more than eight times more than last year, and almost three times the previous record year of 2009!
So what the heck is going on?
I’ve read several articles, which all allude to the sea lions’ food source–forage fish such as herring, anchovies, and sardines–“mysteriously” disappearing. But is there really a mystery? The forage fishery in California is a big industry. Could it be that the valuable market for these fish, too low on the food chain for our dinner, but a popular source of food for livestock, fish farms, fertilizer, and even those omega 3’s the doctor told you to take, could be over-fished?
“A presumed food shortage is leaving last year’s baby sea lions in bad shape; as mothers spend more time foraging for fish, pups wean themselves early and set out on their own, before they’re strong enough to find their own food. Starving and exhausted, they seek refuge along the state’s beaches. At this point, scientists still don’t know what that cause is, and a food shortage still seems like the most plausible culprit. This isn’t an El Niño year, and the pattern doesn’t resemble what scientists would expect to see if an environmental toxin or infectious disease were to blame.”–Nadia Drake, Wired
Although the forage fishery in California claims to be one of the best managed in the country, if not the world, that estimation is based solely on the catch they have consistently been able to get–in fisheries jargon, “maximum sustainable yield.” But this measurement does not consider the ramifications for the ecosystem, nor the predators that depend on these fish as their only food source. Just last year the Fish and Game Commission recognized this oversight and revised its policy. Based on the recommendations from the Lenfest Forage Fish Report, the new policy takes into account the “effects of fishing on forage species’ dependant predators, and the availability of alternative prey.” With the Pacific sardine fishery currently on its way to collapse, much like it did in 1945, dropping 33 percent from last year and in decline for six years, the Pacific Fisheries Council just adopted similar language for their management of forage fish.
But for this year’s sea lions, it may be too little too late.
On March 25, 2013, NOAA officially declared a Federal “Unusual Mortality Event” (UME) and formed a team of researchers to investigate. NOAA Fisheries, the National Marine Mammal Foundation, and the Working Group for Marine Mammal Unusual Mortality Events are investigating the food shortage hypotheses, comparing the abundance of forage fish and the correlation to sea lion weight. This data will also help us to better manage for other forage-dependant predatory species such as harbor seals and sea birds.
“These sea lions might be our sentinel that tells us something else is going on that’s going to be affecting other fish, that’s going to be affecting sharks, that could have much broader concerns throughout the ocean.”–Sarah Wilkins of National Marine Fisheries Service, in an interview with NPR.
If we can understand the factors that have created this immediate issue, we may be able to better manage ocean resources in the future. However, this crisis begs the bigger philosophical question of whether or not a wild ecosystem is something that can be, or should be, “managed” by humans. Do we really need to be fishing out hundreds of thousands of metric tons of wild menhaden from the Chesapeake Bay, krill from the Antarctic, and sardines and squid from the California Pacific just to get Omega 3’s or feed pigs? As a lynchpin for the whole ecosystem, these fish have much more value left alive in the ocean than they do dead as fertilizer on a corn crop. Most of these wild-caught forage fish, ironically, end up feeding farmed fish–and starving their wild counterparts! (It takes 7 pounds of sardines to grow one pound of pen-raised tuna.) Climate change has made it even more difficult to predict when and where these fish will be. Without that consistency, it’s virtually impossible to “manage” an ever-changing ocean ecosystem.
Given the limitations on our ability to effectively manage the ocean, it would be prudent to adopt a more cautious strategy in regards to wild forage fish, assuring there is enough for dependant wildlife. We have other sources of Omega 3’s and fertilizer, but marine animals and sea birds rely solely on what they can find in the wild ocean. Since forage fish abundance is already highly variable and sensitive to the environmental changes that we are certain to experience in the future, it will be increasingly difficult for wild predators to find a meal–and nearly impossible for man to know the true impact of commercial fishing on the ecosystem. Considering this year’s radical upsurge in mortality of sea lions in California, the assumption many scientists are making is that we are taking more forage fish than we should.
Just as healthy plump sea lions and seals are being returned to California’s wild ocean, US policy makers and scientist are meeting with governments around the world to decide the fate of another important forage fish, krill, in Antarctica. July 15 and 16th the Commission for the Conservation of Antarctic Marine Living Resources (CCAMLR), meets to decide whether or not to protect one of the last remaining healthy ocean ecosystems, The Ross Sea. The most productive stretch of water in the Southern Ocean it is home to whales, penguins, seals, fish, sea birds, and abundant with the food they need to sustain them, mainly krill.
“The Southern Ocean is of major importance, given its wealth of biodiversity, including fish that can live in waters below zero degrees (Celsius, 32 degrees Fahrenheit),” said Robert Calcagno, director of the Monaco Oceanographic Institute”It is also connected to the world’s ocean current system, and has massive stocks of krill,” he said, referring to the tiny shrimp that is a vital protein source for whales, penguins and seals.
Commercial fishing interests are already extracting over 4,000 million tons of krill and 3,000 tons of Antarctic Toothfish (sold as Chilean Sea Bass) from the Southern Ocean each year. Against the advise of scientists studying the region, some fishing interests would like to scale up operations to meet demand. If approved by CCAMLAR this week, The Ross Sea protection would create a 2.75 million square mile wild ocean sanctuary continuing to provide refuge and food for threatened marine life.
Big things do indeed come from small beginnings, forage fish are the corner stone of marine ecosystems, from whales to seabirds, marine wildlife depends on abundant small schooling fish to survive. For little “Sharp Scissors” and the other rehabilitated pups in California returning to the ocean, I hope they find enough nourishment to keep them there.
Originally published on Oceanviews, National Geographic.
Featured Photo: The Marine Mammal Center in Sausalito, Calif., took in 45 malnourished sea lion pups (including those pictured here), seven harbor seals, 12 elephant seals and two fur seals from centers in southern California that were overcrowded and needed more room to accommodate incoming patients. Photo: Ingrid Overgard/The Marine Mammal Center