Brassy Minnow

Characteristics

Elongate in body form and slightly compressed laterally. Body scales have about 20 lines that fan out from the focus of the scale. This feature sets them apart from the Plains, Western, and Silvery minnows, which have 10 radii. Their color is dark dorsally, shading to yellowish-brassy sides, and creamy belly. Breeding males have a brassy hue, hence the origin of the common name. The small mouth, without barbel, is sub-terminal. It has a complete lateral line with 36 to 40 scales. Pharyngeal teeth have grinding surfaces arranged in a 4-4 formula. The intestine is long and coiled, and the peritoneum is black.

Distribution

Widely distributed throughout Iowa, but is usually more common in northern Iowa. It is less prevalent in southwestern Iowa than it is in central and north-central Iowa. It is extremely rare in the Mississippi and Missouri Rivers.

Foods

Mainly bottom ooze and aquatic insect larvae.

State Record

State Records are not documented for non-game species.

Expert Tip

Extensively used as baitfish.

Details

In Iowa, the Brassy Minnow prefers pools in medium-sized streams and small rivers as well as overflow ponds in the floodplain. It is often found in waters with a population of Fathead Minnows. The largest populations of Brassy Minnow can be found in small weedy pools or small, moderately clear streams with slow to moderate current and sandy or gravel bottoms covered with organic sediment.

The Brassy Minnow spawns in quiet water in spring or early summer. Brassy minnows will establish populations in ponds and lakes, although they are seldom abundant in this type of habitat.  Adults reach 3- to 4-inches long. 

Recent stream sampling information is available from Iowa DNR's biological monitoring and assessment program.

Sources:

Harlan, J.R., E.B. Speaker, and J. Mayhew. 1987. Iowa fish and fishing. Iowa Conservation Commission, Des Moines, Iowa. 323pp.

Loan-Wilsey, A. K., C. L. Pierce, K. L. Kane, P. D. Brown and R. L. McNeely. 2005. The Iowa Aquatic Gap Analysis Project Final Report. Iowa Cooperative Fish and Wildlife Research Unit, Iowa State University, Ames.

Illustration by Maynard Reece, from Iowa Fish and Fishing.