ST. PAUL (AP) -- Half of Minnesota's bat species are nearing extinction because of a potentially fatal fungal disease.

The Minnesota Department of Natural Resources released its bat population survey findings on Thursday. The department found that the disease called white-nose syndrome has killed up to 94 percent of bats that hibernate in state-monitored caves and abandoned mines.

The fungus produces a white, powdery substance and is known to only harm hibernating bats. Minnesota has four bat species that hibernate and four that migrate south for the winter.

Department mammalogist Gerda Nordquist says researchers are concerned the hibernating bats will soon be completely wiped out in Minnesota.

Nordquist says the dramatic decline in bats could lead to an increase in insect populations. Bats help reduce mosquitoes and some agricultural crop pests.

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