PIERRE, S.D. (AP) — Prairie chicken and grouse numbers are down sharply from last year on the Fort Pierre National Grassland in central South Dakota, and officials say the drought a year ago is a likely reason.

Biologists say there's no cause for alarm because populations in recent years have been strong, meaning hunters could still see a good year.

The federal grassland sprawls across nearly 181 square miles south of Fort Pierre. This year's survey indicates prairie chicken numbers are down more than a third from 2012 and sharp-tailed grouse are down by more than half.

U.S. Forest Service wildlife biologist Ruben Mares tells the Capital Journal that last year's drought created unfavorable conditions for chick survival and also might have left fewer insects for the birds to eat.

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