Never use mothballs or other artificial pesticides near your chickens! Sources indeed vary on the efficacy of deterring raccoons with unpleasant odors. There are certain odors that raccoons may not like. For example, we read that mothballs may deter raccoons from confined spaces. However, we've read from several reliable sources that mothballs aren't safe for chickens. Securing your chicken coop so the raccoon can't gain access is a much better, safer, and wiser way to protect your chickens.