Geese that died in mine pit had lesions in throats, stomachs

BUTTE, Mont. – Necropsies found geese that died late last year after landing in the toxic waters of a former open pit copper mine in Montana had severe internal tissue damage that appeared to have been caused by a corrosive substance.

A report released by the U.S. Fish and Wildlife Service says copper and zinc – which were found in the birds’ stomachs – could have been the cause or contributing factor in the lesions in their throats, stomachs and intestines.

Between 3,000 and 4,000 snow geese died after a late migration combined with a sudden storm forced the birds to seek refuge in Berkeley Pit in Butte.

Montana Resources environmental affairs manager Mark Thompson tells The Montana Standard that there was never any suspicion that the birds died from a cause other than exposure to the acidic water.