Trolling for Trash

This has been a mixed couple of years for the California condor recovery program. On the hopeful side, captive-bred condors were released at Pinnacles National Monument, and the Big Sur flock is doing well. But that news was countered by the shooting of Condor AC-8, who had been set free to serve as a mentor for zoo-raised birds; the matriarch was shot during a pig hunt sponsored by the owners of Tejon Ranch. Then there were deaths of condor chicks hatched in the wild.

There was more bad news this August. A hatchling condor was found dead below its nest near Hopper Mountain in the Los Padres National Forest, with a gut full of trash. A second bird, taken to the Los Angeles Zoo for treatment of a broken wing, had swallowed half a pound of detritus, including 35 bottle caps. Several chicks that succumbed earlier also contained alarming amounts of hardware.

You might tend to blame feckless captive-reared parent birds, unable to tell trash from honest carrion, for these deaths. But the story is more complex than that.

As scavengers, California condors have specialized in the carcasses of large mammals—mammoths and ground sloths back in the Pleistocene, later beached whales and sea lions, cattle, deer—and the bones are more than even their powerful beaks can handle. But they need calcium to build their own bones, and they’ve met that need by bringing bone fragments small enough to swallow, and bonelike objects such as marine shells, back to their nests. Ornithologist Noel Snyder has seen adult condors picking over defleshed skeletons in search of small bones, and chicks sifting through their nest floors for bone fragments.

So the parent condors were doing something that had worked for their kind for millions of years: picking up small hard objects and bringing them to their chicks. They just weren’t equipped to discriminate between bones and bottle caps.

A similar problem has affected Laysan and black-footed albatrosses.

There are few birds that approach the California condor for sheer presence, but albatrosses are among them. I’ve seen these long-winged seafarers on Monterey Bay (and the single Laysan that keeps returning to Point Arena for the winter), but we’re only on the periphery of their vast cruising ranges. They nest on the remote northwestern islands of the Hawai’ian chain, hours by air from Honolulu, immense distances from anywhere else—but unfortunately not beyond reach of the crap we throw away.

Albatrosses have suffered enormously at human hands. Plume hunters ravaged the coral atolls and volcanic crags where they breed; a species once common off California, the short-tailed albatross, was driven almost to extinction. In the 19th century, albatross eggs were collected for making albumen photographic prints. When the northwestern Hawai’ian islands became strategic territory, the US Navy found itself sharing air space with collision-prone seabirds; to reduce the hazard, Marines and civilian construction workers clubbed thousands of “gooney birds” to death. Other nesting islands became military bomb-practice targets.

But after the war in the Pacific, most of the islands slipped back into obscurity, and the albatrosses prospered under legal protection. Then came a more insidious threat: floating plastic. In Eye of the Albatross, ecologist Carl Safina describes watching a parent Laysan attempting to feed her chick but gagging on a green plastic toothbrush, and seeing the carcass of a young albatross, “its whole rib cage packed with plastic,” including the legs of a toy soldier. Safina also catalogues what he found on the once-pristine beaches of Laysan Island: an astroturf welcome mat, golf tees, and plastic toy trucks, elephants, tyrannosaurs.

Foraging albatrosses look for floating objects as cues to food. That’s particularly true of black-foots, whose diet consists in large part of flying-fish eggs. The fish lay their eggs on flotsam: in the past, bits of pumice, driftwood, kelp; now, mostly driftplastic. Whatever the eggs adhere to, the albatross swallows whole. Pumice gets harmlessly regurgitated; plastic is another story. Plastic is not nutritious, and it’s good at absorbing and concentrating non-water-soluble pollutants like DDT and PCBs.

The albatrosses, doing what has worked for them for their long evolutionary history, bring cigarette lighters and plastic buffaloes back to their hungry chicks. An unquantifiable number of chicks die. And more plastic keeps entering the marine food chain. In a Natural History article last year, oceanographer Charles Moore estimated that the North Pacific subtropical gyre, the Texas-sized swirl of currents where the albatrosses feed, contains 3 million tons of plastic debris, the lethal effluvium of consumer society.

The bottle caps that choked the condor may have been made in the USA; the plastic that’s killing the albatrosses is primarily Japanese in origin. It doesn’t really matter. What’s dismaying is that neither the Southern California wilderness nor the far Pacific is free from our refuse. The death of another condor may seem like small potatoes at a time when we may well re-elect a president who’s still in denial about global warming. But it’s critical enough for those birds, whose time-tested ways of making a living have turned deadly.

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