Midway birds exhibit
signs of lead poisoning
Baby gooney birds on Midway are developing lead poisoning by eating paint chips, despite cleanup efforts when the island was converted to a National Wildlife Refuge from a military base.
"The chicks are eating paint chips directly -- it's not from contaminated soil," reported Myra Finkelstein, a University of California, Santa Cruz, graduate student who is studying the birds, "and knowing that can help guide remediation efforts."
Results of a study by Finkelstein and colleagues Donald Smith and Roberto Gwiazda appeared in the August issue of Environmental Science & Technology.
Midway, about 1,200 miles west-northwest of Hawaii, is home to the largest known Laysan albatross breeding population -- about 65 percent of the total global population. The last census in 2001 counted 287,000 breeding pairs of the albatrosses, also known as gooney birds.
The Navy spent millions of dollars scraping lead-based paint from buildings and repainting with oil-based paint after closing its facility there in the mid-1990s.
Still, the UCSC team found high levels of toxin in chicks.
The toxic metal damages the birds' nervous systems and many aren't able to hold their wings tucked up against their bodies. The wings drag on the ground, a symptom of lead poisoning called "droopwing."
Many chicks don't have droopwing but may suffer other effects that lower their chances of survival, Finkelstein said. When they reach fledgling stage and parents abandon them, the birds starve because they can't fly, she said.
The droopwing symptom is comparable to the "wrist drop symptom" of high-level lead poisoning in humans, said Lee Ann Woodward, resource contaminant specialist in Honolulu for the U.S. Fish and Wildlife Service's National Wildlife Refuge.
She said the refuge has funding from the service to evaluate how extensive any remediation effort would be. Corrective action could involve removing contaminated soil or repainting old buildings to stabilize the lead-based paint, she said. Droopwing has been seen only around the buildings.
"This is a phenomenon we've been aware of a long time," said Beth Flint, refuge wildlife biologist. A number of scientists have studied it, she said.
Theories have differed, however, about the source of lead in the chicks and method of exposure.
Some believed the birds are ingesting lead indirectly from contaminated soil, an important route for lead-poisoned children in the United States.
But an analysis of the chicks' blood by the UCSC researchers specifically identified the chicks as getting lead by eating paint on the buildings or paint chips falling around their nests.
"This problem isn't only found at Midway," Flint said. "We also have small patches historically at Tern Island at French Frigate Shoals."
Seabirds also may be affected by buildings at Johnston Atoll, she said. "Wherever humans built buildings and used lead paint is risky for seabirds."
Usually, it's fatal to chicks that hatch on sites around the buildings, she said. "We don't know the proportion of reproduction we lose. Adult birds seem able to cope with it. It's just the little guys who sit there and chew on the soil and paint chips the first few months of their life.
"It's depressing when you see an egg next to the building and know it may be doomed."
Flint said they are looking at interim steps to protect the birds until the soil is cleaned.
For instance, a certain kind of fabric the birds don't like to nest on is used when a building is being demolished or when ditch-digging is done to prevent nesting in dangerous spots, she said. "To do a whole island would be a pretty major job."
Midway has about 14 species of migratory seabirds other than Laysan albatrosses, but the gooney birds appear to be the only ones affected by lead poisoning, Woodward said.
