Rats moving into Clintonville force residents to change some of their habits. A recent study by the Columbus Public Health Department shows a widespread rat invasion. The Columbus Health Department recently studied the Clintonville area north of Ohio Stateâs campus. It found that a third of 885 properties showed signs of rat activity. Spokesman Jose Rodriguez explains what the health workers have seen. âWhat we look for is for active rodent signs which include anything from burrows on the ground, fresh rat droppings. Weâre looking for exposed rat hairs. Weâre looking for food tracks, really anything that would show us the presence of rats on that property," says Rodriguez. Rodriguez says Clintonville residents are being advised to eliminate sources of food and water that could attract rats including composting piles, bird feeders and pet waste. He says the rats may have been living in the Olentangy or Scioto Rivers which are undergoing major overhauls.