After 115 mallard ducks died last month near Salmon, most likely from a fungal infection, Idaho Fish and Game officials say they believe the worst has passed.

Fish and Game biologist Mike Demick said in a press release the ducks apparently died from acute aspergillosis, their original theory. It is a respiratory tract infection caused by a fungus in soil, dead leaves, moldy grain, compost piles or decaying vegetation. The source of the fungus is no longer available, so the die-off has ended. It can't be passed from duck to duck, Demick said. Biologists also tested for avian influenza. Tissue samples were not consistent for the bird flu, but more tests are being conducted to determine the exact cause, he said.

People who eat a duck which was exposed to the fungus won't get infected, but Demick warned it can still be transmitted if a person inhales spores from contaminated duck carcasses. 

About 50 dead ducks were found Dec. 7 after someone reported seeing dead ducks in an irrigation ditch. By the end of the month, about 115 dead birds were found near Salmon.