Snow geese migrate in huge, honking flocks, each bird winter-white except for a beak and wing tips smudged black. A single flock may comprise tens of thousands of birds. When the geese land en masse, bird hunters call it a swirl, as though a twister were touching down rather than four-pound animals.(1)
A huge flock of migratory birds landed on acidic waters of an open pit mine where employees attempted to scare them off. Several thousand snow geese have died after a snowstorm forced large flocks to take refuge in the acidic, metal-laden waters of an old open pit mine in Montana.
This was no ordinary pond, however. It was the 700-acre Berkeley Pit, a former mine now submerged in water as acidic as distilled vinegar. From 1955 until operations ceased in 1982, miners extracted nearly 300 million tons of copper ore from the pit. They left behind an immense crevasse, which filled with water
They left behind an immense crevasse, which filled with water 900 feet deep. Concentrated within the floodwater are arsenic, cadmium, cobalt, copper, iron, zinc and other inorganic compounds.(1)
Mark Thompson, an environmental affairs manager for mine company Montana Resources, said witnesses described the pit as like “700 acres of white birds” on 28 November.
Since 28 November, employees of MR and Arco had used spotlights, noise makers and other efforts to scare or “haze” the birds off the water and prevent others from landing.
The companies estimated that more than 90% of the birds had been chased off by 29 November, Thompson said.
Workers received some advance notice about the incoming flock from an off-duty Montana Resources employee about 25 miles away, who called to report there were about 25,000 geese in the air in Anaconda, Thompson said. The employees worked hard to save the birds, he said.
Thompson said federal and state agencies were still confirming the number of dead geese. Nonetheless, the company expected the total would be many times more than the 342 that died in 1995, prompting a mitigation effort that seeks to protect birds from the toxic water (2). To read more click here
