The smallmouth bass is generally brown (seldom yellow) with red eyes, and dark brown vertical bands. There are 13–15 soft rays in the dorsal fin. The upper jaw of smallmouth bass extends to the middle of the eye. Males are generally smaller than females. The males tend to weigh around two pounds. Females can range from three to six pounds. Their average sizes can differ, depending on where they are found. Those found in American waters tend to be larger due to the longer summers, which allow them to eat and grow for a longer period of time. Their habitat plays a significant role in their color, weight, and shape. Smallmouth that live in dark water (such as rivers) tend to be rather torpedo-shaped and very dark brown. Smallmouth bass that live in sandy areas of lakes, tend to be a light yellow-brown and are more oval-shaped.