In 1995, researchers announced that the population of tiny marine organisms called zooplankton off the coast of southern California had declined by a stunning 70 percent over the last twenty years. Scientists linked the decline in zooplankton, a food source for several species of fish in the region, to a 2-to-3-degree F. increase in the area's surface water temperature over the last four decades. The warming seas have created a vast wasteland with few birds and few fish.
John McGowan, a biologist at the Scripps Institution of Oceanography and co-author of the March, 1995, study, recalled observing abundant fish and bird life during his cruises in the area in the 1960s. But, he told the Associated Press, during a recent voyage he was "flabbergasted to see the difference." McGowan said the startling decline in the zooplankton population raises questions about the survival of sardines, anchovies, hake and Pacific mackerel. The rising water temperature, McGowan said, was robbing surface waters of nutrients like nitrates and phosphates that the plant plankton need to survive. Because the zooplankton feed on the plant plankton, the loss of nutrients ripples up the food chain.
McGowan wrote in a March, 1995 article in the journal Science, that over past few decades there has been a significant warming in the top 600 feet of water which has led, among other things, to the collapse of commercial anchovy fishing in the area.
Dr. Dick Veit, a zoologist at the University of Washington, said the findings were consistent with other studies that had shown stunning losses of fish and sea bird populations along the Pacific Coast. Veit said he had discovered a decline of 90 percent in the population of one group of sea birds in the region.
"Warming of Seas Creates a Pacific Wasteland Off San Diego," New York Times, March 5, 1995.
"Climate-Ocean Variability and Ecosystem Response in the Northeast Pacific," John A. McGowan, Daniel R. Cayan and LeRoy M. Dorman, Science, Vol. 281, July 10, 1998.