| River chub | |
|---|---|
 | |
| Nocomis micropogon | |
Scientific classification  | |
| Domain: | Eukaryota |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Actinopterygii |
| Order: | Cypriniformes |
| Family: | Cyprinidae |
| Genus: | Nocomis |
| Species: | N. micropogon |
| Binomial name | |
| Nocomis micropogon (Cope, 1865) | |
| Synonyms | |
| |
The river chub (Nocomis micropogon) is a minnow in the family Cyprinidae. It is one of the most common fishes in North American streams.
The river chub is a robust minnow, dark olivaceous above to dusky yellow below, with orange-red fins, large scales, a large slightly subterminal mouth, and a small barbel (whisker-like organ) at the corners of the jaw. During the breeding season, sexually mature males develop pinkish-purple coloration, and swollen heads with tubercles between the eyes and snout tip (they are sometimes called hornyheads). [3] The river chub grows to a maximum of about 33 centimetres (13 in), with males larger than females. Common length is about 13.5 cm (5.3 in). [4]
The river chub is among the most common fishes in North American streams. [5] [6] Its range extends primarily through most of the Great Lakes and Appalachian regions. [4] The river chub is found in clear, medium to large creeks and rivers with moderate to swift current over rock and gravel substrate, from southeast Ontario and southern New York to Michigan and Indiana, south to northwest South Carolina to northwest Alabama. This includes the Susquehanna River system, James River system, Great Lakes basin (except Lake Superior), Ohio River basin, Santee River, Savannah River, and Coosa River. [2] It has been introduced into the Ottawa River system in Ontario, and may owe its presence in the Santee, Savannah and Coosa Rivers to introduction by fishermen emptying bait buckets. [7] The river chub is generally considered widespread and abundant with no apparent major threats. Exceptions are Illinois, where it is considered Critically Imperiled in its very limited range on the Wabash River; Alabama, where it is considered Imperiled; and in Georgia it is ranked as Vulnerable. Populations in Ohio have been extirpated by turbidity and siltation in western regions and are threatened by acid mine drainage in the coal region. [8] Also, dams have inundated areas that were once habitat for the river chub eliminating bits of its range.[ citation needed ]
The river chub is prey for larger fish and is used as bait by fishermen seeking large game fish such as bass and catfish. Its diet consists primarily of aquatic invertebrates. One study of river chub stomach contents in western New York found that insects were 70% of the volume of food consumed, plants or protists 20% (mainly filamentous algae), crustaceans 5% (primarily Cambarus ), and mollusks 4% (primarily gastropods), plus a few fish and arachnids. Caddisfly larvae and fly larvae (primarily Simulium and Chironomus ) made up just over half the total food consumed. Mayflies (mainly baetids) were about 6% of the total. Other insects consumed were Coleoptera (beetles), Hemiptera (true bugs), Hymenoptera (bees, wasps, and ants), Plecoptera (stoneflies), Neuroptera (net-winged insects like laceflies), and Lepidoptera (butterflies and moths). [9]
The river chub presence in a stream is a good indicator of water quality. They are intolerant of pollution, turbidity and siltation, and require a minimum pH 6.0. [10] They provide ecological services to mussels (as glochidia hosts), and nest associates, some of which may not spawn in its absence. [11] [12] [13] Fresh-water mussels release small masses of microscopic larvae known as glochidia in a loose gelatinous matrix. The glochidia encyst on the gills of river chubs where they metamorphose into juveniles and then drop off. It is suspected that the river chub feeds on the gelatinous masses as it does drifting insects. [11] [12] The river chub is host to mussels including the endangered fine-rayed pigtoe, Tennessee clubshell and probably many other amblemine glochidia. [11] [12]
Nest associates of the river chub include species of the Clinostomus , Luxilus , Lythrurus , Notropis , Chrosomus , Rhinichthys , and Semotilus genera. [3] [14] Preference for river chub nests by nest associates may be due to a lack of spawning habitat for some species, but some require the association with pebble nest builders to reproduce. For example, in an effort to establish a more viable population, pebble nest associate Chrosomus cumberlandensis was bred in aquaria with a man made pebble nest, and milt from a breeding male river chub was added to induce spawning. [13] Nest associates and host may equally benefit from their affiliation. Also, hybridization among nest associates is not uncommon. One example is the Nocomis micropogon X Rhinichthys cataractae which is sometimes identified as Pararhinichthys bowersi . [14]
The river chub lives up to 5 years, reaching sexual maturity in its second year. In late spring the breeding male builds a pebble nest close to the bank of the stream in low to moderate current. [5] Females produce about 500-1000 eggs that are probably spread among several different males’ nests. [3] The pebble nest also provides spawning habitat for several other minnow species. [14]
In early spring the adult male river chub undergoes pronounced changes in his appearance in preparation for breeding. His head swells and grows well-developed tubercles from eyes to snout tip. Small tubercles grow on the outer part of his first several pectoral fin rays and his body develops a pinkish-purple coloration. [15] When the water temperature reaches 16–19 °C (61–66 °F) he finds an area in low to moderate current, typically 0.5–1 m (1 ft 8 in – 3 ft 3 in) deep and begins to build a pebble nest. [5] Nest construction begins with the river chub male creating a shallow depression 0.5–1 m (1 ft 8 in – 3 ft 3 in) in diameter by removing the stones with his mouth and depositing them on the lateral margins. Next, collecting a relatively uniform set of up 10,000 pebbles about 1 cm (0.39 in) in size from as far away as 25 m (82 ft), he builds a short platform and then a 20–30 cm (7.9–11.8 in) high circular mound with a central trough on the upstream slope. When a gravid female enters the trough he presses her against the side by placing his caudal peduncle over hers and lodging her head between his opercle and pectoral fin. The male fans the nest and defends it from rivals with head butting and circle swim behaviors. [16]
The eggs hatch in 5–6 days and the larvae grows to become a 19 mm (0.75 in) long juvenile in about 57 days. [14] At two years the river chub is 95–110 mm (3.7–4.3 in) and sexually mature. Its maximum life span is 5 years and it can grow up to 33 cm (13 in). [4] In addition to the breeding male's changes, other sexual dimorphic characters include slightly larger paired, anal, and dorsal fins in the female, and faster growth rate and larger size in the male. For example, a typical four-year-old male is about 18 cm (7.1 in) and female about 13 cm (5.1 in). [15]
River chub is one of the most common fishes in its range. About 20% of North American minnows are considered imperiled. None of the imperiled is a mound builder like the river chub. [6] The main threats it faces are pollution, siltation, and habitat destruction primarily by dam building. Like many minnow species it requires flowing water over coarse substrate to reproduce so dams impact its range negatively. Dams can also trap the stone and gravel sediments and keep them from replenishing the waters below. This sediment-starved condition has impacted some species, such as the redd nesting northern hog sucker and black redhorse, that require natural deposits of coarse material to spawn, but typically the river chub continues to be able to find gravel to build its own spawning habitat. [5]
The river chub does suffer where pollution, turbidity and siltation, acid mine drainage and acid precipitation/deposition impact its habitat. It has been extirpated in areas with excess turbidity and siltation in western Ohio. Riparian buffers in agricultural areas can help keep turbidity and contaminants from waterways. The Swatara Creek in Pennsylvania had no fish due to acid mine drainage. Limestone treatments and wetlands were built to mitigate the acid mine drainage and the river chub was one of the first species to return. [10]
Rhinichthys, known as the riffle daces, is a genus of freshwater fish in the carp family (Cyprinidae) of the order Cypriniformes. The type species is Rhinichthys atratulus, the blacknose dace. Rhinichthys species range throughout North America.
The lake chub is a freshwater cyprinid fish found in Canada and in parts of the United States. Of all North American minnows, it is the one with the northernmost distribution. Its genus, Couesius is considered monotypic today. The genus was named after Elliott Coues, who collected the holotype specimen.
The Tennessee shiner is a species of fish in the family Cyprinidae, the carps and minnows. It is native to the southeastern United States.
The Tennessee dace is a species of ray-finned fish in the family Cyprinidae. It is found only in the United States; particularly in northeast Tennessee and southwest Virginia, and parts of extreme northwest Georgia. Until recently, they were considered a subspecies of mountain redbelly dace. They are commonly found in East Tennessee in spring fed first-order streams, often in silt and fine gravel pools, or undercut banks. These streams usually do not exceed two meters in width.
The Sandhills chub is a species of freshwater fish in the family Cyprinidae of order Cypriniformes. There are 4 species of Semotilus, 2 of which occur in South Carolina. This fish is found only in North Carolina and South Carolina. The Sandhills chub is predominately found in the Carolina Sandhills and some areas of Cape Fear, Pee Dee and Santee river drainages. It is characterized by its robust body, large head and lack of a dark blotch or smudge on their dorsal fin which is present on the closely related Creek Chub. The Sandhills chub has fine scales, a pinkish body and can be up to 9.4 inches.
Pleurobema oviforme, the Tennessee clubshell, is a species of freshwater mussel in the family Unionidae, the river mussels. It is native to the eastern United States, where it occurs in Alabama, Kentucky, North Carolina, Tennessee, and Virginia. It also previously occurred in Mississippi.
The hornyhead chub is a small species of minnow in the family Cyprinidae of order Cypriniformes. It mainly inhabits small rivers and streams of the northern central USA, up into Canada. The adults inhabit faster, rocky pools of rivers.
Semotilus atromaculatus, known as the creek chub or the common creek chub, is a small minnow, a freshwater fish found in the eastern US and Canada. Differing in size and color depending on origin of development, the creek chub can usually be defined by a dark brown body with a black lateral line spanning horizontally across the body. It lives primarily within streams and rivers. Creek chubs attain lengths of 2–6 inches (5.1–15.2 cm) with larger specimens of up to 12 inches (30 cm) long.
The carmine shiner is a freshwater fish species. In Manitoba, it was once known as the rosyface shiner. Based mostly on zoogeographic data, it is currently classified as a distinct species within the rosyface shiner species complex. The carmine shiner is a member of the Minnow family, Cyprinidae. It has the following characteristics and distinguishing features:
The rosyface chub is a species of freshwater fish in the carp family (Cyprinidae), found in the United States.
The cheat minnow is a demersal, freshwater fish endemic to the United States, most commonly found in the Ohio River basin.
The scarlet shiner is a freshwater fish native to the eastern United States.
The redtail chub is a freshwater fish found in the U.S. states of Tennessee and Kentucky.
The bluebreast darter is a small species of freshwater ray-finned fish, a darter from the subfamily Etheostomatinae, part of the family Percidae, which also contains the perches, ruffes and pikeperches. It is endemic to the eastern United States from New York and Illinois to Tennessee and North Carolina.
The gilt darter is a species of freshwater ray-finned fish, a darter from the subfamily Etheostomatinae, part of the family Percidae, which also contains the perches, ruffes and pikeperches. It can be found in a number of states in the Mississippi River drainage of the United States although it has been extirpated from some river systems in which it was at one time present, mostly due to siltation and pollution problems. Males are more colorful than females and can grow to a length of about 9 cm (3.5 in). It is a benthic fish that feeds primarily on small aquatic insect larvae. Males form territories during the breeding season in late spring and early summer. Spawning typically takes place at the upper ends of riffles with sandy and gravelly bottoms interspersed with larger cobbles. Some organisations are endeavouring to conserve populations of the gilt darter and re-introduce it to states where the fish has been extirpated but suitable habitat still exists.
The laurel dace is a species of freshwater minnow native to the U.S. state of Tennessee. It was first discovered in 1976. A very rare species, it has only been found in localized populations in six small streams on the Walden Ridge portion of the Cumberland Plateau in Tennessee. It is found in six streams: the Soddy, Horn, Cupp, Young's, Moccasin, and Bumbee Creeks, all of which drain into larger rivers that eventually feed the Tennessee River. It is believed to be extirpated from Laurel Creek, the only other stream where it was known to occur.
The gravel chub, also known as the spotted chub, is a freshwater minnow from the family Cyprinidae. This species of fish has a spotted distribution inhabiting various small rivers and streams in North America. The gravel chub requires a highly specific clean habitat making it vulnerable to various types of pollutants and in need of conservation efforts.
The bluehead chub is a cyprinid native to North America. Its name is due to its appearance, as breeding males have a blue head and develop large nuptial tubercles. Adult bluehead chubs are, on average, between 70 and 160 mm in length. They have a robust body with uniformly large scales. The scales are present on the belly and breast. They have a pored body, a weakly falcate pectoral fin, and pharyngeal teeth. They have a large mouth, small eyes, and a terminal barbel. Other characteristics include a darkened lateral band, spot on the caudal fin, and red coloration of the fins and iris of the eyes. They have 40 lateral line scales and 8 anal rays. The bluehead chub is a freshwater fish, and lives in pools, rivers, and streams. They feed on insects and plants.
The bigmouth chub is a species of fish native to West Virginia.
The Dixie chub is a species of freshwater ray-finned fish from the carp and minnow family Cyprinidae. It is endemic to southeastern United States.
