Pregnant heifers and breeding bulls aren't the only animals for sale at western South Dakota's Custer State Park. Seventeen burros also are up for bidding Saturday during the annual buffalo auction.
The park's donkeys, which aren't native, were once used for rides to the top of Harney Peak. That stopped decades ago, and the burros were released into the park.
Visitors Services Coordinator Craig Pugsley says the donkeys quickly became popular with park-goers. He says they're Custer's second-most beloved animals, after the bison.
Visitors feed the animals, which have become so friendly that they stick their heads inside cars and lick windshields in hopes of getting a treat.
Park officials say that about 35 burros will remain in the park. Last year, burros sold for less than $50 each.