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Sea Lion Deaths leave Scientists Swimming
ENN News, March 3, 2000

Scientists are searching for clues to explain the high mortality rate of Australian sea lion pups.Sea lion populations in Australia are sinking in alarming numbers, and researchers from CSIRO, the country's national science agency, are at a loss to know why. "The sea lion colonies should be bouncing back from over-harvesting last century," said CSIRO researcher Peter Shaughnessy, who has studied sea lions since 1990. "We don't know why they aren't." In 1999, sea lion pups died in record numbers at a major breeding colony near Port Lincoln on Australia's western coast. The mortality rate exceeded 40 percent, sounding a loud alarm for scientists.

Some 3,000 seals die in Caspian Sea
Associated Press, May 23, 2000

An epidemic has killed more than 3,000 seals along Kazakstan's Caspian Sea coast and scientists fear that the entire population of the animals could be wiped out, officials said Tuesday. A report by the Kazak Agency for Emergencies said the bodies of the dead seals had been collected and destroyed, but that the cause and type of epidemic had not been determined. Experts from Russia, Kazakstan and Great Britain were trying to determine the nature of the epidemic.

Scientists are Stumped by Dwindling Numbers of Sea Lions
By Lee Dye,, June 29, 2000

Where they used to see thousands, they now see hundreds. Where they used to see hundreds, they now see a few. Often, they see none at all. The population of Steller sea lions in the northern and western Pacific Ocean has declined so much that many scientists say the once-noisy rookeries scattered along the Aleutian Islands now seem more like ghost towns. These great behemoths of the north, as graceful in the water as they are awkward on land, have declined by over 80 percent in the last 30 years throughout the area from central Alaska’s west coast to Japan. A recent report by the National Marine Fisheries Service says the Steller sea lion, which has been on the endangered species list since 1990, may be headed for extinction.

Some believe the fishing industry has depleted the Steller sea lion's food supplies.The reason for the dramatic decline from more than 250,000 to fewer than 50,000 animals appears obvious: the Steller sea lion competes for food with the aggressive commercial fisheries of the northern Pacific, and the lion is no longer the king of that jungle. “The best available evidence indicates food limitation remains the primary hypothesis for the ongoing decline of the species,” the National Marine Fisheries Service concludes in a recent report. That statement is based primarily on the fact that commercial fishing for pollock, cod and mackerel (the sea lion’s primary diet) has grown explosively in the northern Pacific at the same time that the population of sea lions has gone down. But with such qualifiers as “best available evidence” and “primary hypothesis,” the statement also reveals a level of uncertainty that is unacceptable to a multi-billion dollar fishing industry that could be severely curtailed.

The simple fact is that nobody knows for certain what’s going on here, and finding the right answers to the right questions is very difficult. The scientific basis for limiting the fishery is so woefully lacking in evidence that a federal judge in Seattle recently found that authorities don’t have the data needed to make the right decisions to protect the sea lions while limiting the fisheries. The reason for the uncertainty lies chiefly in the nature of the beast. The Steller sea lion, also called the northern sea lion, is indeed a monster of the deep. Males can be more than 10 feet long, and weigh more than a ton, and they can dive to depths of more than 600 feet. They range from Southern California’s Channel Islands to the Arctic and to the coasts of Russia and Japan. They make their homes in some of the planet’s most inhospitable places, like the barren islands of the Aleutians that divide the Bering Sea from the Gulf of Alaska, making it virtually impossible for scientists to monitor their activities over a long period of time.