Return-path: <WHE_WILLIAM@FLO.ORG> Received: from FLO.ORG by VMSVAX.SIMMONS.EDU (PMDF V5.0-4 #8767) id <01HXI4HM4NJ495FTYW@VMSVAX.SIMMONS.EDU> for whalenet@VMSVAX.SIMMONS.EDU; Sat, 11 Nov 1995 03:55:21 -0400 (EDT) Date: Fri, 10 Nov 1995 13:58:35 -0500 (EST) From: Michael Williamson <WHE_WILLIAM@FLO.ORG> Subject: Case Study: Sea Lions and DDT To: whalenet@VMSVAX.SIMMONS.EDU Message-id: <951110135835.3f5c@FLO.ORG> Content-transfer-encoding: 7BIT From: SMTP%"MARMAM@UVVM.BITNET" 9-NOV-1995 12:00:45.60 To: WHE_WILLIAM CC: Subj: Sea Lions-DDT Date: Thu, 9 Nov 1995 08:25:39 -0800 Reply-To: Marine Mammals Research and Conservation Discussion <MARMAM@UVVM.BITNET> Sender: Marine Mammals Research and Conservation Discussion <MARMAM@UVVM.BITNET> Comments: Warning -- original Sender: tag was rbaird@SOL.UVIC.CA From: firstname.lastname@example.org Subject: Sea Lions-DDT X-To: email@example.com To: Multiple recipients of list MARMAM <MARMAM@UVVM.BITNET> Sea Lions-DDT By JANE E. ALLEN AP Science Writer LOS ANGELES (AP) -- Two decades after DDT dumping ended in Southern California waters, sea lions have dramatically lower levels of the pesticide and their population has more than doubled. The huge decline of the pesticide in the sea lions' fatty tissue represents the greatest reduction observed in any animal population, according to researchers at the University of California, Santa Cruz. California sea lions once had the highest body fat concentrations of DDT of any marine mammal ever studied by the National Oceanic Atmospheric Administration. DDT, a powerful pesticide that causes premature births in sea lions, has been banned in this country since 1972. Montrose Chemical Co., once the nation's largest DDT producer, dumped the pesticide off the Palos Verdes Peninsula from 1947 to 1971. From 1975 to 1993 the sea lion population at San Nicolas, San Miguel, Santa Barbara and Santa Cruz islands increased from 12,000 to 28,000. Sea lions migrate each year to the Channel Islands for a breeding season from May to August and feast from a food chain contaminated by DDT. In 1970, the sea lions' blubber showed an average level of DDT -- and its more dangerous byproduct DDE -- of 760 parts per million. Blubber samples taken in 1988-92 showed levels had fallen to 5.2 parts per million, according to the findings published this month in Britain's Marine Pollution Bulletin. The dumping, however, left an estimated 100 tons of DDT-contaminated sediments on the ocean floor and lingering effects of the pesticide remain unknown. "We're not out of the woods," said lead study author Patricia Lieberg-Clark, a wildlife biologist at the environmental consulting firm BioSystems Analysis Inc. "There still is that DDT deposit that's sitting there in San Pedro Channel that will continue to be churned up for God knows how long." The study was funded by the Institute of Marine Science at UC Santa Cruz and the National Science Foundation.