Smallmouth Buffalo (Ictiobus bubalus)

Smallmouth Buffalo
Smallmouth Buffalo

The smallmouth buffalo is second only to the bigmouth in the sucker family in terms of size and commercial importance, although it has a better reputation as a food fish than does its larger relative. The smallmouth buffalo, however, is less abundant and subsequently less commercially important.


A deep-bodied and compressed fish, the smallmouth buffalo has a small conical head, a high-arched back, and a long dorsal fin. It also has a small, thick-lipped mouth with distinct grooves on the upper lip; the upper jaw is considerably shorter than the snout.

Usually lighter in coloration than other buffalo, it is gray, olive, or bronze on the back; black to olive yellow on the sides; white to yellow on the belly; and it has an olive bronze sheen. The pelvic fins are olive or grayish black, and the other fins are indistinctly dark.

It bears a noticeable resemblance to the bigmouth buffalo, but it can be distinguished by a more compressed body and a more steeply arched back. It also possesses a smaller, subterminal mouth that lies laterally; the bigmouth buffalo’s mouth lies at a slant. Characteristic of all suckers, the mouth extends downward, a noticeable feature when the smallmouth buffalo is feeding.


Growing slower than the bigmouth, a smallmouth buffalo can reach 36 inches in length. The average commercially taken fish are in the 2- to 10-pound range, although some specimens weigh 15 to 20 pounds. The all-tackle world record for a smallmouth buffalo is 82 pounds, 3 ounces.

Life history/Behavior

Spawning and schooling habits are similar or identical to those of the bigmouth buffalo.

Food and feeding habits

Smallmouth buffalo feed on shellfish and algae, grinding them with the bony plates in their throats designed for that purpose; they eat more insects and bottom organisms than bigmouth buffalo do.

Other Names

razorback buffalo, roach-back, thick-lipped buffalo, channel buffalo, hump-backed buffalo, high-back buffalo, river buffalo.


Found only in North America, the smallmouth buffalo has a range similar to that of the bigmouth buffalo. It occurs in the Lake Michigan drainage and the Mississippi River basin, from Pennsylvania and Michigan to Montana and south to the Gulf of Mexico, and from Mobile Bay, Alabama, west to the Rio Grande in Texas and New Mexico. It is also found in Mexico and was introduced in Arizona. It is most abundant in the central states.


Smallmouth buffalo inhabit pools, backwaters, large streams, and main channels of small to large rivers, as well as warm lakes and reservoirs. They prefer slightly cleaner and deeper waters than do bigmouth buffalo, an explanation for their relatively smaller numbers.