Gudgeons are small freshwater fish belonging to the family Gobiidae. They are typically found in rivers, lakes, and ponds across Europe, Asia, and North America. Gudgeons have elongated bodies, usually measuring between 3 to 6 inches in length, and are characterized by their large eyes and small mouths. They often inhabit shallow waters with sandy or gravelly bottoms. These fish are known for their social behavior, often forming schools. Gudgeons primarily feed on small invertebrates, such as insects and crustaceans. They play a role in the aquatic ecosystem by serving as prey for larger fish and birds, contributing to the food web.