Sea otter numbers take a turn for the worse

By Peter Fimrite, Chronicle Staff Writer
Monday, August 16, 2010 (08-16) 12:22 PDT SAN FRANCISCO — The California sea otter – which fought back from near extinction after a century or so of wholesale slaughter – appears to again be hitting the skids, and nobody can figure out the reason. It is the second consecutive year of decline for the cuddly-looking sea mammals after a decade of small but encouraging increases in their numbers. The U.S. Geological Survey’s study of the state’s otters, also known as southern sea otters, counts the whiskered shellfish eaters each year and reports a three-year average to account for variables. This year’s figure of 2,711 otters along the California coast represents a 3.6 percent decline compared with the 2009 survey. Even more disturbing is the 11 percent drop in the number of otter pups compared with last year. … The 2009 average was 2,813, down 0.46 percent compared with the previous three years. It was the first decline of a three-year average since the mid-1990s, researchers said. Besides another decline, this year’s study found that the geographic distribution of the furry critters had shrunk. There were fewer otters at the northern and southern ends of their range, which is from Pigeon Point to Gaviota State Park, researchers said. What’s clear, Tinker said, is that large numbers of sea otters are dying. “Our data suggest that breeding-age females are dying in higher-than-usual numbers from multiple causes, including infectious disease, toxin-exposure, heart failure, malnutrition and shark attacks,” Tinker said. …