An influx of fur seals at The Marine Mammal Center could be an indication that an El Niño winter is upon us. Fur seals, which are actually a type of sea lion, are pelagic animals, meaning that they spend most of their lives far out at sea. When young pups start showing up on beaches, separated from their mothers and suffering from malnutrition, it means that something is happening out in the ocean that is disrupting their normal life cycles. The Marine Mammal Center is a rescue hospital which rehabilitates distressed, sick, and injured animals, nursing them back to health, and eventually releasing them back to the ocean. The El Niño winter of 2009 was preceded by a large number of fur seal pup strandings along the California coast, and The Marine Mammal Center had as many as 36 fur seal patients at one time that year.
An El Niño winter is caused by a climate pattern that occurs in the tropical Pacific Ocean about every five years. The name comes from the Spanish words for "the child." It refers to the baby Jesus, whose date of birth in December coincides with the time of year in which this climate pattern often begins to manifest itself. Scientists looking at the chemical signatures found in coral specimens have determined that the El Niño weather pattern has been around for at least 3,000 years. As far back as the year 1500, Peruvian fishermen noticed that the periodic warm waters were holding down their harvest of anchovies. They dubbed this phenomenon El Niño because it usually occurred around the time of Christmas.
El Niño is caused by a warming of surface temperatures in the eastern Pacific combined with high air surface pressure in the western Pacific. The variations spread across the ocean through the Equatorial Current and the Humboldt Current, causing extreme weather such as storms, floods, and droughts. Extreme storms can cause fur seal pups to become separated from their mothers in the first few months after birth, at a time when they are not yet able to fend for themselves. The El Niño effect also has an impact on marine mammals’ food supplies, which can be disrupted by fluctuations in water temperatures.
Of the nine species of fur seals in the world, eight of them belong to the genus Arctocephalus and one of them has a genus of its own, Callorhinus. Two of these species are found in the Northern Hemisphere, the northern fur seal (Callorhinus ursinus) and the Guadalupe fur seal (Arctocephalus townsendi). Both of these types of fur seals can be found in the waters off the coast of California, although they are relatively rare compared to their sea lion cousins.
The northern fur seal gets the scientific name of its genus, Callorhinus, from the Greek words kallos, which means "beautiful object" and rhinos, which means "skin" or "hide." This refers to the soft luxurious pelt that was highly prized by hunters, almost leading to the extinction of these animals in the early 20th century. The species name ursinus means "bear-like" in Latin and the similarity to bears can be seen in the faces of fur seals. While the northern fur seal has come back from the brink of potential extinction, it is still listed as vulnerable under the U.S. Endangered Species Act. Threats include predation by orcas, competition with fishermen, and the effects of climate change. Their current population, which ranges across an arc of the North Pacific from Japan to Alaska and down the west coast to Baja California, is approximately 1.2 million.
The Guadalupe fur seal also has bear-like characteristics and the scientific name of its genus, Arctocephalis, means "bear-headed" in Greek. The specific name townsendi comes from C. H. Townsend, an American scientist who conducted research on these animals in 1892 on Guadalupe Island, off the coast of Baja California. Guadalupe fur seals breed on this island and San Miguel Island in the Channel Islands of California. Their range extends from the central California coast down as far south as the tip of Baja California. Because of this, it is somewhat rare for them to be brought into The Marine Mammal Center, although when they are rescued, they often come from the Center’s Monterey Bay or San Luis Obispo field operations.
Commercial hunting of Guadalupe fur seals nearly wiped out the species and it was thought to be extinct in the early 1900s. A few animals were then found on Guadalupe Island and on San Nicolas Island in the Channel Islands in 1949. The Mexican government created a pinniped sanctuary on Guadalupe Island in 1975 in order to protect the few remaining members of the species and hopefully restore its population. The Guadalupe fur seal is listed as endangered in the U.S. under the Endangered Species Act. Its total population in both the U.S. and Mexico is estimated to be only about 10,000.
I have been a volunteer at The Marine Mammal Center for almost three years and have seen how the ups and downs of climate patterns affect the lives of marine mammals. I missed the big influx of fur seals that happened in 2009, but the climatic forces that caused it then may be coming back around again. We were at the beginning of a very busy season for harbor seals when I started in early 2010. By August, all of our harbor seal patients had been released and I went on to work with sea lions. We had a few fur seals that year, both northern and Guadalupe, but never more than one or two at a time. The following spring saw the arrival of elephant seal pups, affectionately known to us as "ellies."
The most fulfilling experience that a volunteer at The Marine Mammal Center can have is to attend a release, when a rehabilitated animal gets to go back to its ocean home. After a seal or sea lion is deemed fit to go back to the wild, the animal is taken in a carrier to a beach and let go. It is gratifying for the volunteers to see the animal go back to where it belongs, after feeding and caring for it over a period of several weeks. The animals love it too, and often seem to be running joyously back into the ocean. Many releases take place at Chimney Rock, near Point Reyes, while others may be further afield such as the Fitzgerald Marine Reserve near Moss Beach. Occasionally sea lions are released at Rodeo Beach, just down the hill from the Center.
Now The Marine Mammal Center has mostly sea lion patients, which can arrive at any time of year. The number of fur seal patients is up to seven and a few more have been coming in each week since late October. So far, all of them are northern fur seals. Fur seal patient number seven for this season is named Sparkle, and she is a tiny little nine-pound pup. She was found at Drakes Beach in the Point Reyes National Seashore, dazed, malnourished, and disoriented. I had the opportunity to meet Richard James, the man who found her and called The Marine Mammal Center to rescue her. Richard, AKA "The Coastodian," has an excellent blog in which he tells the whole story of Sparkle's rescue, along with several photographs and a YouTube video. He was kind enough to allow me to use one of his photos, which shows Sparkle sitting nobly in the sands of Drakes Beach. Sparkle had to be fed with a tube when she first arrived at the Center, because she was so young when she was rescued, she had not yet learned how to eat fish. Now, less than two weeks later, she is happily eating fish and displaying a healthy feistiness.
The Marine Mammal Center had an unusual fur seal patient last August, when a northern fur seal was rescued on a beach on the Hawaiian island of Oahu. This was the first sighting ever of a northern fur seal in Hawaii, as these seals are normally found further north in the Pacific Ocean, or the Bering Sea and Sea of Okhotsk. The female fur seal was suffering from malnutrition and suspected of carrying the morbillivirus, an infectious disease that could have posed a severe threat to the endangered Hawaiian monk seal. She was rescued by the Oahu Marine Mammal Rescue Network and brought to the Honolulu Zoo for temporary care, until she could be FedExed to Oakland and transported to The Marine Mammal Center. The fur seal was named Golden Missy, after Olympic swimmer Missy Franklin, who had just won four gold medals at the 2012 Summer Olympics in London.
After her arrival at The Marine Mammal Center, Golden Missy was given a thorough medical examination and a series of tests to see if she was carrying morbillivirus. She was quarantined away from the other patients, which were mostly sea lions at that time. After lab tests came back, she was found to be free of the morbillivirus, although she did have a high white blood cell count and a couple of small cookiecutter shark bites. After a three-week stay at The Marine Mammal Center, Golden Missy was released back to the ocean on August 23, at Chimney Rock in the Point Reyes National Seashore. She had a satellite tag attached to her, so her movements can be tracked as she readjusts to life in the wild.
The Marine Mammal Center is a partner with the National Park Service and the Golden Gate National Recreation Area, where the Center has its state-of-the-art facility on the site of an old Nike missile base. Its primary function is as a rescue hospital, but it also serves to educate the public about issues related to ocean health, sustainable practices, and threats posed to wildlife by human activity. New volunteers are always welcome and the next Introduction Meeting is on Saturday, February 9. The Marine Mammal Center is located at 2000 Bunker Road in the Marin Headlands, just up the hill from Rodeo Beach. It is open from 10:00 AM to 5:00 PM daily, except Thanksgiving, Christmas and New Year's Day. The Center has exhibits and two observation areas where the public can view the patients. Admission is free and docent-led tours are available for a small fee.