( CNN ) Idaho wildlife officials have retrieved 2,000 dead snow geese that fell from the sky this week . The birds , whose carcasses were collected over the weekend , appear to have died of avian cholera , the Idaho Department of Fish and Game said Tuesday . `` The migratory birds were on the return leg of their migration from the southwestern United States and Mexico to their breeding grounds on the northern coast of Alaska , '' said Steve Schmidt , a regional supervisor . They died near Dubois , Terreton and Roberts -- all in the eastern part of the state . It 's unclear where the geese picked the bacteria from , but authorities are scrambling to ensure that other birds do n't feed on the carcasses and spread the disease . `` The important thing is to quickly collect as many of the carcasses as possible , to prevent other birds from feeding on the infected birds , '' Schmidt said . `` Biologists observed about 20 eagles in the vicinity of some of the carcasses . Because of a delayed incubation period it is uncertain where these eagles might be located , if and when the avian cholera affects them . '' Though the official lab results are not out , officials said the cause of death points to avian cholera . Humans are not considered at high risk of getting the disease , according to U.S. health officials .
The birds were on the return leg of their migration from the U.S. and Mexico . A spokesman for the National Park Service said that a helicopter was called to help with the rescue.