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bigmouth buffalo

bigmouth buffalo (Ictiobus cyprinellus)
Photo © Engbretson Underwater Photography

Features and Behaviors


The average life span of a bigmouth buffalo is seven to eight years. This fish typically averages two and one-half pounds in weight and 15 to 27 inches in length. It may attain a maximum length of 40 inches. The large head contains a sucker-type mouth with large lips. The body is brown or coppery on the back, black to yellow-green on the sides and white to yellow on the belly. The fins are brown or black. The dorsal fin is long.


The bigmouth buffalo lives in deep pools of rivers, lakes and impoundments. This fish lives in schools in midwater or near the bottom. Reaching maturity at age three, it spawns in spring. The female deposits about 400,000 eggs which are scattered over the bottom in shallow water. Eggs hatch in eight to 14 days. This fish eats insects and small crustaceans that it strains from the water with its gill rakers (long, hard extensions of the bones supporting the gills).

Illinois Range


Kingdom: Animalia
Phylum: Chordata
Class: Actinopterygii
Order: Cypriniformes
Family: Catostomidae

Illinois Status: common, native