CREEK CHUB
SCIENTIFIC NAME: Semotilus atromaculatus
CHARACTERISTICS: The creek chub is a rather robust, rounded minnow with a characteristic dark blotch at the base of its dorsal fin. The head is large, the mouth large and oblique. The upper lip is wider in the middle than at the sides, and a small barbel is usually present just forward from each corner of the mouth. The back is typically dusky olive. A broad, faint band extends along the sides and ends in a quadrate spot at the caudal fin base. Breeding males acquire red-orange color in the dorsal fin base and along the lower fins, with a pink flush along the lower head and sides. While Semotillus atromaculatus closely resembles the Dixie chub, S. thoreauianus, the two have differently configured caudal spots and head tubercle counts.
ADULT SIZE: 3.9 to 11 in (100 to 279 mm)
DISTRIBUTION: Semotilus atromaculatus is found throughout North America from Manitoba and New Mexico east to the Atlantic and Gulf slope drainages. It occurs extensively in the Mobile basin and Tennessee River drainage in Alabama.
HABITAT AND BIOLOGY: Although found in a variety of habitats, the creek chub prefers small headwater streams where there are few competitors. In late summer, this is often the only species found in intermittent pools of headwater streams. Semotilus atromaculatus is a generalized predator, consuming whatever food is available: plant material, insects, small fishes, worms, crayfishes, and mollusks. Its aggressive behavior undoubtedly helps it to survive in stressful environments. Spawning in Alabama occurs from April to June over gravel nests built by males. Creek chubs have a pitridge form of nest construction (Johnston and Page, 1992). Males construct depression in the substrate by removing gravel with their mouths, and after spawning in the depressions, they cover the eggs with gravel from new pit construction. This formation of a single ridge is followed by successive excavation-spawning-burial episodes. Ross (1976, 1977) describes the creek chubs" mating behaviors, social interactions, and aggressive nature. Sexual maturity is reached by the second year (Shemske, 1974), and creek chubs may live to be five or more years old.
ORIGINAL DESCRIPTION: The creek chub was described by Mitchill in 1818.
ETYMOLOGY:
Semotilus means spotted banner, referring to the dorsal fin.
Atromaculatus means black spotted.
The copyrighted information above is from Fishes of Alabama and the Mobile Basin.
