[CINC] Sea Lion News From Up North

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Sick sea lions present a mystery

_Jane Kay, Chronicle Environment Writer_ (mailto:jkay at sfchronicle.com)  
Friday, June 19, 2009
Fluctuating ocean conditions may be depleting the food supply of young sea 
lions that are turning up skinny and ill on California beaches, mirroring 
the fate of Brandt's cormorants earlier this spring.  
The animal strandings are so numerous that the newly expanded Marine Mammal 
Center in Sausalito can't keep up. Only those young sea lions most in need 
of help are being brought in for treatment - up to 20 a day - leaving others 
to try to make it on their own, center representatives say. 
Scientists agree that the youngsters, born nearly a year ago on the Channel 
Islands off Southern California, aren't getting enough food. But they're at 
a loss to determine whether the sea lions' favorite foods - northern 
anchovies and sardines - are hard to find because they're moving south in response 
to falling and rising ocean temperatures. That's the suspected scenario for 
the Brandt's cormorants. More than 500 of the birds, which also eat the 
anchovies and sardines, were picked up starving or dead in April and May by the 
Farallones Beach Watch program. 
Or scientists wonder whether a U.S. record number of pups born last year on 
the Channel Islands means there are more around to fail during the 
sensitive transition from nursing to hunting for food on their own. 
Drawing global interest is yet another theory: that the marine mammals and 
the seabirds are signaling an early warning of an El Niño, the warm-water 
current from the tropical Pacific. 
El Niño brings rain. But it would also suppress the vigorous upwelling of 
nutrients in the California Current, stretching from Baja California to 
Vancouver, needed to produce abundant krill, fish and other aquatic life. 
The last big El Niño occurred in 1997-98, starving thousands of marine 
mammals and seabirds from a host of species along the Pacific Coast. Rain doused 
Northern California, heavy snow fell on the East Coast and hurricanes 
brewed in the Atlantic. An El Niño is overdue, scientists say. 
As of Thursday, the Marine Mammal Center had 136 patients in its new $32 
million center, which opened to the public Monday. 
Of the patient load, 85 were sea lions receiving nourishment through 
feeding tubes and treatment for organ failure and other problems. By comparison, 
there were 53 sea lions under care two weeks ago. 
"They're just too weak to try to forage. You can see their bones," said 
center spokesman Jim Oswald. So many beach reports are coming in that the 
center has to choose where to respond. There aren't enough trained rescue crews 
or vehicles to bring in - or even check on - every animal, he said. 
Lack of resources
That was the case June 12 when Salesforce.com CEO Marc Benioff was walking 
with his spouse, Lynne, on Baker Beach in San Francisco and came upon a sea 
lion with an injured tail, probably from a boat strike. He called the center 
but was told that the staff didn't have the resources to come by 
immediately. 
"It's sad because you want to help," Benioff said. "It's a mammal. It's 
like looking into the eyes of your golden retriever." 
So far this June, the center has received more than 1,200 calls - more than 
twice the number of calls for this period last year. 
The center's territory stretches 600 miles along the coast, and it has 
branches in Morro and Monterey bays.  
"We believe it's food supply," said Joe Cordero, a biologist with National 
Marine Fisheries Service, a department of the National Oceanic and 
Atmospheric Administration. 
His theory is that the burgeoning California sea lion population of 300,000 
is producing so many pups that more of the yearlings are showing up on the 
beaches after weaning at 6 months to 1 1/2 years. 
Mark Lowry, research fishery biologist at the National Oceanic and 
Atmospheric Administration's Southwest Fisheries Science Center in La Jolla (San 
Diego County), echoed Cordero's assessment. 
"There was a record number of pups born last year - 59,000 - which were 
recently weaned. The fact that some of these weaned pups are struggling is not 
surprising. Not all survive to adulthood." 
Water getting warmer
That could be the case, other scientists agree. But other possibilities are 
the fluctuating ocean temperatures, some related to global warming. Surface 
temperatures had remained low for most of the spring. But in recent weeks - 
about the time that the sea lions started showing up on the beaches - the 
ocean temperatures rose in the tropical Pacific from about 50 degrees to 65 
degrees.  
The Climate Prediction Center, run by the National Weather Service, in 
early June noted that sea surface temperatures were increasing across the 
equatorial Pacific, and anomalies in heat content typically precede the 
development of El Niño. Current observations, recent trends and some forecast models 
indicate that conditions are favorable for a transition to El Niño conditions 
during June through August. The next forecast is expected July 9.  
"The water went from being pretty cold to pretty warm in a couple of weeks. 
It's been spiking all over the place," said William Sydeman, a biologist 
and president of the Farallon Institute for Advanced Ecosystem Research in 
Petaluma. 
Even though there isn't a full-blown El Niño, he said, predators - such as 
marine mammals and seabirds that feed on fish - "oftentimes will send 
signals. They'll start to respond actually before you see changes in the physical 
environment. They integrate everything that happens in the food web." 
Ocean temperatures
The National Marine Fisheries Service's yearly trawl brought in valuable 
information on temperature and fish in the Gulf of the Farallones between May 
28 and June 14. The water was around 50 degrees, moderately cool in the 
California Current. The trawls caught good numbers of juvenile rockfish, hake 
and lingcod as well as krill, all cool-water species. For a second year, 
anchovies were absent and there were few sardines. The anchovies favored by sea 
lions and seabirds head to normal spawning grounds in Southern California 
when the waters are cool. Sea lions in Southern California are also being found 
malnourished, but in smaller numbers. 
"We don't see strong signs yet of a developing El Niño in coastal waters of 
central California. We see the culmination of a cold and productive 
seasonal upwelling. But we wouldn't necessarily see those (El Niño) signs this 
early," said John Field, fisheries biologist at the Southwest Fisheries Science 
Center in Santa Cruz. 
But, surprisingly early for this time of year and a possible sign of a 
brewing El Niño, a fisherman reported seeing the jumbo squid, a South American 
species that follows a warm current, up in Washington state.  
E-mail Jane Kay at _jkay at sfchronicle.com_ (mailto:jkay at sfchronicle.com) 
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