Researchers started studying how remnant DDT in the environment could be at play. Given the lead poisoning that often befalls a condor scavenging farther inland, many point to marine mammals as a critical food source for the species’ long-lasting survival in the wild.īut in 2006, when condors released along the Big Sur coast finally started to mate, many of their eggs failed to hatch. After decades of painstaking work, there are now 537 California condors, supported by a network of breeding centers and reintroduction sites from Baja California to Northern California.Ĭalifornia After more than a century, California condors soar over Yurok tribal lands once againĪfter being pushed to the brink of extinction, condors have returned to a slice of their Northern California habitat for the first time in 130 years. Saving this critically endangered species is particularly tricky: It takes more than six years before a condor is ready to reproduce, and even then, the birds tend to lay only one egg every other year. By 1982, there were only 22 California condors left on the planet.įederal and state wildlife officials, with the support of conservation advocates, agreed to capture every last bird in hopes of breeding the population back to vitality. Its numbers plummeted, however, in the wake of trophy hunting and an increasingly contaminated environment. With its bald, prehistoric-looking head and a wingspan that stretches almost 10 feet, Gymnogyps californianus remains the largest land bird in North America and is a sight to behold in the wild. Many native people such as the Chumash have come to see the giant birds as central to their culture. (Ken Bohn / San Diego Zoo Wildlife Alliance)Ĭondors commanded the skies as early as the Pleistocene, when mammoths, saber-toothed cats and other megafauna prowled California. If the California condor is accumulating such high amounts of DDT, that means that every link of the coastal food chain - including people - is also exposed.
Just because we banned DDT 50 years ago doesn’t mean it has gone away - especially in California, said Eunha Hoh, whose lab at San Diego State’s School of Public Health led the chemical analysis in the new condor study.
Another study based in Oakland found that DDT’s hormone-disrupting effects are affecting a new generation of women - passed down from mothers to daughters, and now granddaughters. Significant amounts of DDT-related compounds are still accumulating in Southern California dolphins, and a recent study linked the presence of dichlorodiphenyltrichloroethane to an aggressive cancer in sea lions. As many as half a million barrels could still be underwater today, according to old records and a UC Santa Barbara study that provided the first real glimpse of this pollution bubbling 3,000 feet under the sea near Catalina Island. Public calls for action have intensified since The Times reported that the nation’s largest manufacturer of this pesticide once dumped its waste into the deep ocean. This latest study builds on much-needed research into DDT’s toxic - and insidious - legacy in California. “They don’t kill a bird outright, but … they could interfere with estrogen receptors or any other endocrine pathway.”
“This DDT story, and contaminants interfering with reproduction, is what we call a sublethal exposure,” said Tubbs, a reproductive sciences expert at the San Diego Zoo Wildlife Alliance. One mysterious chemical that is likely connected to the DDT dumping in California was 56 times more abundant in coastal condors and 148 times more abundant in California dolphins. Looking at the birds’ coastal food sources, researchers found that dolphin and sea lion carcasses that washed ashore in Southern California were also seven times more contaminated with DDT than the marine mammals they analyzed along the Gulf of California in Mexico. In a sophisticated chemical analysis published Tuesday in Environmental Science & Technology, the team found that DDT-related chemicals were seven times more abundant in coastal condors than condors that fed farther inland. Now, after years of study, Tubbs and a team of environmental health scientists have identified more than 40 DDT-related compounds - along with a number of unknown chemicals - that have been circulating through the marine ecosystem and accumulating in this iconic bird at the very top of the food chain. Climate & Environment Here’s what we know about the legacy of DDT dumping off L.A.’s coastĭDT was banned 50 years ago, but its toxic legacy continues to affect the California marine ecosystem and threaten various animal species.
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