Creek Chub

The creek chub is a small chub with a greenish-brown back, cream-colored sides interrupted by horizontal black stripes running from the nose to the tail, and a white belly. Having a round, cylindrical body with a compressed posterior, males average 125 mm (4.9 in) in length, while females average 105 mm (4.1 in). As the specimen eats what is directly in front of it, the mouth is terminal, large and under the anterior of the eye.

A fish which can withstand many different environments, the creek chub's current range is the eastern two-thirds of the US and southeastern Canada. It can quickly adapt to different extreme environments, and can live on many different foods. Documented to span throughout the Great Lakes surrounding Wisconsin, and into Minnesota, this species has been described as plentiful. However, reports of this species have fallen throughout Wisconsin and the Great Lakes, suggesting a decline in its population in these regions.

The creek chub is described as an opportunist and a carnivore, and consumes many different foods to survive, including fish, insect remains and vegetation, amphipods, adult Coleoptera, Ephemeroptera nymphs, Odonata larvae and Diptera adults and larvae.

Feeding habits are specific to the creeks and rivers where in the chub exists. As a juvenile, it actively feeds throughout the early morning on organisms within the water. Fish often do not leave their shelter until temperatures have increased to a daily maximum. Large chubs actively forage for 1–2 hr, then wait in their environment to feed on drift items.

The creek chub has specific behaviors at different ages. Commonly a school fish, they have been documented to school from birth to late adult, occupying the edges of pools. Their upper lethal temperature is 32 °C (90 °F), while the lower lethal temperature is 1.7 °C (35.1 °F). Initially, the creek chub is quite hesitant to venture from its known territory. For instance, while developing and growing, a school of creek chub travels together within the same 50-metre (160 ft) radius. Ensuring safety from unknown predators and environment, this increases their potential for survival.

Males increase reproductive success by migrating to a spawning area. The male then initiates building a spawning site to draw in females in the surrounding area. This most likely occurs in small pits with small pebbles to protect the area where eggs are laid. Once females enter, the male wraps around her pectoral fin and body, fertilization occurs, and the female leaves. Around 25–30 eggs are released each fertilization cycle. Often, these reproductive cycles occur in communal nesting sites, where the male controls the territory and protects it from intruders.

During the breeding season, males grow small, keratin-based bumps, called nuptial tubercles, on their head, which are used in ritualized combat. This hardly ever gets dangerous or destructive, but it is used to ward off intruding males on communal nesting sites.