128 



Here's how the latest pesticide disclosures came to light. 



In 1968, a young zoology student, Daniel Odell, observed a large number of 

 aborted sea lion pups strewn across the beaches of San Miguel and Santa Barbara 

 islands. Odell, now ^ is a UOLA ecologist investigating the population dynamics 

 of California sea lions and elephant seals. He learned that abortions among the 

 channel island herds had been reported as early as 1949 — but never in their 

 present high numbers. 



Two years ago, Odell began making monthly surveys of the 10,000 to 12,000 

 sea lions on San Nicolas Island southwest of Los Angeles. Breeding begins 

 there each June, and the pups are bom during the spring. "Aborted" young ac- 

 tually emerge alive, but they are premature and quickly die. 



In 1969, Odell counted 135 aborted pups from January to mid-May. The follow- 

 ing year the number rose to at least 550, then fell off to 389 this spring. 



What about the young who survived? There were only 2,300 in 1970 and sub- 

 stantially more — 3,500 — this year. From a population of at least 7,500 aduit 

 females, however, neither baby crop was impressive. Odell thinks many more 

 pups were aborted at sea. 



Evidence strongly implicating DDT in this drama has now been brought for- 

 ward by three West Coast researchers, William Gilmartin, John Simpson and 

 Robert De Long. Last spring, they examined six female sea lions who had just 

 aborted their yoimg and four who had borne healthy pups. They found no signifi- 

 cant age differences between the two groups. They fo\ind no differences in viral, 

 bacterial or stress diseases. What they did find was a striking disparity in the 

 levels of DDE — the main breakdown product of DDT. 



The aborting females had 8^ times as much toxic DDT in their blubber as did 

 the nonaborting females. 



"We could hardly believe it," says Gilmartin, a microbiologist with the Naval 

 Undersea Research and Development Center in San Diego. "There was this 

 dramatic gap in pesticide levels between the two groups — no overlap at all. The 

 relationship between DDE and the abortions is so strong that it is probably 

 causal, though we won't really know without more research." 



De Long, a biologist with the Commerce Department's National Marine Fish- 

 eries Service in Seattle, points out that the aborting sea lions also had high 

 levels of mercury and very high levels of PCBs — toxic chemicals that are in- 

 creasingly being used in paints, insulation and plastics. "In combination with 

 DDT," he says, "the PCBs may have had a doubly grave impact on sea lion 

 reproductivity. Those animals were really hot." 



The work of Odell, Gilmartin, Simpson and De Long raises some tantalizing 

 questions. Why, for instance, do female sea lions from the same island show 

 such striking differences in DDT and PCB concentrations? 



"The answer may lie in the migratory and feeding habits of the herd," says 

 Odell. "Many of the San Nicolas females seem to winter off the coast of Mexico, 

 but some hang around the islands. Very possibly they're the ones picking up most 

 of the pesticides in the squid and fish they eat Around Ventura, there's lots of 

 agricultural runoff into the sea, and in Santa Monica bay the Montrose Chemical 

 Corp. is known to have dumped DDT." 



The crisis of the sea lions comes amid growing evidence that pesticides and 

 PCBs are threatening entire bird species — especially the pelicans, peregrine 

 falcons, bald eagles and Massachusetts sparrow hawks. In 1969, for instance, a 

 breeding population of over 600 brown i>elicans on California's Anacapa Island 

 produced only five fledglings. A related brown pelican population in South Caro- 

 lina withered away from over 5,000 breeding pairs in 1960 to only 1,250 in 1969. 



In all these cases, DDT or PCBs severely deranged the birds' calcium processes^ 

 Females lay eggs so thin-shelled they are crushed in the nests. The few pelican 

 eggs that survived contained over 15 times as much DDT as eggs found in one 

 successfully breeding population. 



But of all the recent developments, the threat to the sea lions is most ominous. 

 Ocean mammals are everywhere threatened, and legislation to save them (the 

 Harris-Pryor bill) has been attacked by the Nixon Administration. Considering 

 the likely new menace of toxic chemicals, isn't it time we halted the commercial 

 killing of sea mammals? 



Finally, the ultimate question : Sea lions are mammals. So are we. If DDT 

 and the PCBs are inhibiting the reproduction of sea lions, what are they doing 

 to us? 



(Copyright 1971, Newsday. Distributed by Los Angeles Times Syndicate.) 



i 



