More than 200 bison escape ranch American bison graze in a lush meadow in Yellowstone National Park, in Wyoming. UPI Photo/A.J. Sisco ASHTON, Iowa, May 17 (UPI) -- Authorities in Iowa said there may be "a few stragglers" among the more than 200 escaped bison that were rounded up. Osceola County sheriff's deputy Lt. Seth Hofman said the more than 200 bison escaped Sunday evening from the Frick and Joe Buffalo Ranch north of Ashton, and the animals quickly spread across five counties, including Nobles County in Minnesota, the Worthington (Minn.) Daily Globe reported Thursday. "We had a lot of concerned citizens call in, because buffalo sightings are pretty unusual," he explained. Hofman said searchers on horseback and 4-wheelers managed to round up most of the creatures, but some of the animals had to be put down for safety reasons. He said the sheriff's department received a few scattered calls Monday through Wednesday about large animals roaming. "There might be a few stragglers, but I think we've got them pretty well taken care of," Hofman said.