on the cover / By Heidi Walters

Fixing the World

“DDT binds to fat, so we don’t get that much of a problem with fish because they’re just not that fat,” said West, who has worked with the condor reintroduction program in Big Sur since 1999. “But animals that are long-lived, like pinnipeds, that have a lot of blubber on them — it just accumulates over the lifetime of that animal. In Big Sur, recently, they found that condors that were feeding on pinnipeds were getting high levels of DDE, which is a breakdown product of DDT. There was a lot of late-stage egg mortality — the chicks died of dehydration from increased water loss through the thinned eggshells. It was similar to what happened in the ‘70s during the height of DDT.”

West said California condors nesting in Southern California far from the coast didn’t have DDT-compromised eggs. The historic record indicates that North Coast-dwelling condors in the past feasted regularly on marine mammals. But West said maybe our resident mammals, at least, like California harbor seals, won’t have been exposed to DDT spills in southern California, and to current use of DDT in countries south of the U.S. border. However, the sea lions that migrate through here might show exposure.

They’re also catching vultures in the region.

“Condors and turkey vultures eat the same things, so we can use turkey vultures as a ‘sentinel’ species,” said West, adding that turkey vultures can survive lead exposure much better than condors can. “But they do absorb it. So we can observe exposure trends in them.”

At the Bald Hills site, they’ve been putting out fresh bait to gain the vultures’ attention. Now they’re pre-trapping — luring the birds into the trap, but with the net walls rolled up so they can escape. Once the birds are used to the trap, it’ll be baited again and someone hiding in a nearby copse will pull a string and lower the net the next time the birds drop in. (The traps will be opened at night so other animals won’t get stuck in them.) Once caught, each bird will be measured and tagged with an ID number, have its blood drawn, then be let go. The blood will be tested for lead and mercury, and possibly DDT.

One problem: Turkey vultures do migrate. They arrive on the North Coast in May, and they leave in August just as hunting season is starting up. But condors, if reintroduced here, would remain during hunting season. So West and Williams are also trapping ravens, who live here year-round, to fill in the picture. Although, said West, the omnivorous ravens aren’t the purest of sentinels.

“They’ll eat cheese puffs at a campground,” he said.

Although the condor eked out a desperate living up until the 1980s in southern California, the last condor to soar over our particular hills may very well have been the poor fellow now ensconced behind glass at the Clarke Historical Museum in Eureka. It was shot sometime in the 1890s up in Kneeland.

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