Lead A Swan Song For Many Birds Heavy Metal Contamination Affects Many Types Of Cda Basin Waterfowl

Dead swans have come to symbolize metals contamination in the Coeur d’Alene River basin, but they aren’t the only birds being poisoned.

Canvasback, redhead and mallard ducks have also died from swallowing lead, according to 1994 study results released Thursday by federal scientists.

Studies before 1992 confirmed lead poisoning in tundra swans, trumpeter swans, Canada geese and common goldeneye.

Since the 1950s, eight species of duck and American coot have been found dead in the basin, although the causes of their deaths weren’t confirmed, according to Dan Audet of the U.S. Fish and Wildlife Service.

“What we found is lead poisoning in geese, swans, diving ducks and dabbling ducks,” he said. “The waterfowl community has different feeding strategies - and all have been affected.”

Audet is field manager for the Natural Resource Damage Assessment, which began in 1992. The studies are being done to determine how much fish and wildlife have suffered as a result of historic mining practices that flooded the river system with lead, zinc and other metals.

Mine tailings line the riverbanks and bottoms, continually washing into the water. Swans eat lead when they reach with their long necks for underwater plants in adjacent lakes. They swallow soil in the process.

The big, white birds are relatively easy to find, Audet said, so people are more aware of their deaths.

But geese, which feed on shoreline grasses as well as underwater plants, are also being poisoned, he said.

The same goes for ducks that dive for plants sprouting on lake bottoms, and ducks whose necks won’t reach as far underwater as swans.

The scientific summaries released Thursday give a glimpse of the legal case that federal agencies are building against mining companies. They filed suit last week to get the companies to pay for cleanup.

Unfortunately, said an industry representative, the summaries are just that - incomplete and interpreted information, not detailed scientific results.

Holly Houston, executive director of the Mining Information Office, also said the variety of birds dying from lead poisoning wouldn’t make a significant difference to industry’s cleanup approach.

“Whether their number (of dead birds) is 15 a year or 20 a year, this is a relatively small number compared to the overall huge number of healthy wildlife in the area,” Houston said.

The government scientists say they can’t find all the birds that die, and are unable to get laboratory information about many bodies they do recover.

According to the information released Thursday:

From 1992 through 1995, scientists found 261 dead animals, mostly waterfowl, in the Coeur d’Alene River drainage. Many of those had been partially eaten by coyotes and other predators; 120 were in good enough shape for laboratory analysis of their deaths.

Of the 120, 68 had died from lead poisoning without the presence of lead shot in their digestive systems. Five had swallowed lead shot, which hunters can’t legally use in the area but may remain from past years, Audet said.

In comparison, 21 dead birds were recovered in the nearby St. Joe River drainage. Thirteen of those were sent to the lab. None died of lead poisoning, except for the four that ingested lead shot.

, DataTimes MEMO: This sidebar appeared with the story: TAINTED SOIL FOUND THROUGHOUT THE FLOOD PLAIN The public information update released Thursday covers a variety of topics from studies of the Coeur d’Alene River basin. Among information in the 18-page summary: Contaminated soil was found at 15 of 18 places checked in the flood plain. Those 15 contained high concentrations of lead, zinc, cadmium and other hazardous substances. The tainted soil ranged from 3 inches to more than 7.5 feet near Rose Lake. The average depth was 2 feet. In 1993 and 1994, 327 tons of zinc and 1,000 tons of lead entered Lake Coeur d’Alene. Most of the zinc (83 percent) came from the mining district above Cataldo. Most of the lead (75 percent) was washed down from the flood plain below Cataldo. There are fewer kinds of trees, grasses and shrubs along the Coeur d’Alene River than in comparable areas away from the mining contamination. That would likely affect animals’ food supplies. Concentrations of metals in sediment, rock slime, invertebrate animals and fish from the Coeur d’Alene River are much greater than those found in the St. Joe River, the North Fork of the Coeur d’Alene River, and the South Fork of the Coeur d’Alene River upstream of the Canyon Creek mining district. - Julie Titone