The central stoneroller (''Campostoma anomalum'') is a fish in the family Cyprinidae endemic to North America.

Biology

Stonerollers have a rounded snout overhanging a crescent-shaped mouth, a hard ridge of cartilage on the lower lip, and irregular patches of dark colored scales on the sides of the body. Breeding males have orange colored fins with a black band on the

dorsal fin A dorsal fin is a fin located on the back of most marine and freshwater vertebrates within various taxa of the animal kingdom. Many species of animals possessing dorsal fins are not particularly closely related to each other, though through c ...

and often on the anal fin; breeding

tubercles In anatomy, a tubercle (literally 'small tuber', Latin for 'lump') is any round nodule, small eminence, or warty outgrowth found on external or internal organs of a plant or an animal. In plants A tubercle is generally a wart-like projection, ...

(keratinized growths) also cover the head, back, and sides of the body.

Distribution

The central stoneroller is widespread in freshwater streams throughout a large portion of the eastern, central, and midwestern

United States The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country primarily located in North America. It consists of 50 states, a federal district, five major unincorporated territori ...

. It is present in the

Atlantic Ocean The Atlantic Ocean is the second-largest of the world's five oceans, with an area of about . It covers approximately 20% of Earth's surface and about 29% of its water surface area. It is known to separate the " Old World" of Africa, Europe ...

Great Lakes The Great Lakes, also called the Great Lakes of North America, are a series of large interconnected freshwater lakes in the mid-east region of North America that connect to the Atlantic Ocean via the Saint Lawrence River. There are five lak ...

Mississippi River The Mississippi River is the second-longest river and chief river of the second-largest drainage system in North America, second only to the Hudson Bay drainage system. From its traditional source of Lake Itasca in northern Minnesota, it fl ...

, and Hudson Bay basins in the US, from New York west to

North Dakota North Dakota () is a U.S. state in the Upper Midwest, named after the indigenous Dakota Sioux. North Dakota is bordered by the Canadian provinces of Saskatchewan and Manitoba to the north and by the U.S. states of Minnesota to the east, So ...

and

Wyoming Wyoming () is a state in the Mountain West subregion of the Western United States. It is bordered by Montana to the north and northwest, South Dakota and Nebraska to the east, Idaho to the west, Utah to the southwest, and Colorado to the s ...

and south to

South Carolina )'' Animis opibusque parati'' ( for, , Latin, Prepared in mind and resources, links=no) , anthem = " Carolina";" South Carolina On My Mind" , Former = Province of South Carolina , seat = Columbia , LargestCity = Charleston , LargestMetro = ...

and

Texas Texas (, ; Spanish: ''Texas'', ''Tejas'') is a state in the South Central region of the United States. At 268,596 square miles (695,662 km2), and with more than 29.1 million residents in 2020, it is the second-largest U.S. state by ...

. Isolated populations are also found in

Canada Canada is a country in North America. Its ten provinces and three territories extend from the Atlantic Ocean to the Pacific Ocean and northward into the Arctic Ocean, covering over , making it the world's second-largest country by tot ...

and

Mexico Mexico (Spanish: México), officially the United Mexican States, is a country in the southern portion of North America. It is bordered to the north by the United States; to the south and west by the Pacific Ocean; to the southeast by Guatema ...

. The central stoneroller is

benthopelagic The demersal zone is the part of the sea or ocean (or deep lake) consisting of the part of the water column near to (and significantly affected by) the seabed and the benthos. The demersal zone is just above the benthic zone and forms a layer of ...

, inhabiting either the midwaters or bottom of freshwater streams and rivers. It requires some current and is most commonly found in

riffle A riffle is a shallow landform in a flowing channel. Colloquially, it is a shallow place in a river where water flows quickly past rocks. However, in geology a riffle has specific characteristics. Topographic, sedimentary and hydraulic indica ...

s and pools of moderate to high

gradient In vector calculus, the gradient of a scalar-valued differentiable function of several variables is the vector field (or vector-valued function) \nabla f whose value at a point p is the "direction and rate of fastest increase". If the gr ...

streams with a gravel substrate bottom. However, it is a very tolerant species and can be found in almost any stream system with adequate food, leading to it widespread distribution.

Ecology

The central stoneroller is generally

herbivorous A herbivore is an animal anatomically and physiologically adapted to eating plant material, for example foliage or marine algae, for the main component of its diet. As a result of their plant diet, herbivorous animals typically have mouthpar ...

, feeding primarily on algae scraped from rocks and logs with the

cartilaginous Cartilage is a resilient and smooth type of connective tissue. In tetrapods, it covers and protects the ends of long bones at the joints as articular cartilage, and is a structural component of many body parts including the rib cage, the neck a ...

ridge on its lower

jaw The jaw is any opposable articulated structure at the entrance of the mouth, typically used for grasping and manipulating food. The term ''jaws'' is also broadly applied to the whole of the structures constituting the vault of the mouth and serv ...

. Young fish feed on

rotifers The rotifers (, from the Latin , "wheel", and , "bearing"), commonly called wheel animals or wheel animalcules, make up a phylum (Rotifera ) of microscopic and near-microscopic pseudocoelomate animals. They were first described by Rev. John H ...

, filamentous algae, and micro crustacea. It also feeds on detritus,

diatoms A diatom (New Latin, Neo-Latin ''diatoma''), "a cutting through, a severance", from el, διάτομος, diátomos, "cut in half, divided equally" from el, διατέμνω, diatémno, "to cut in twain". is any member of a large group com ...

, and occasionally

aquatic insects Aquatic insects or water insects live some portion of their life cycle in the water. They feed in the same ways as other insects. Some ''diving'' insects, such as predatory diving beetles, can hunt for food underwater where land-living insects c ...

. It is classified as a

grazing In agriculture, grazing is a method of animal husbandry whereby domestic livestock are allowed outdoors to roam around and consume wild vegetations in order to convert the otherwise indigestible (by human gut) cellulose within grass and other ...

minnow Minnow is the common name for a number of species of small freshwater fish, belonging to several genera of the families Cyprinidae and Leuciscidae. They are also known in Ireland as pinkeens. Smaller fish in the subfamily Leusciscidae are c ...

in its feeding behavior, and large

schools A school is an educational institution designed to provide learning spaces and learning environments for the teaching of students under the direction of teachers. Most countries have systems of formal education, which is sometimes compulsor ...

of these fish often feed together. Central stonerollers may consume up to 27 percent of their body weight in benthic algae per day. One

Kansas Kansas () is a state in the Midwestern United States. Its capital is Topeka, and its largest city is Wichita. Kansas is a landlocked state bordered by Nebraska to the north; Missouri to the east; Oklahoma to the south; and Colorado to th ...

study found that algae contributed most (47 percent) to the diet of central stonerollers, followed by detritus (30 percent), animal matter (21 percent), and terrestrial vegetation (2 percent). Some human-induced factors that reduce the abundance of the central stoneroller are altered flow regimens, habitat fragmentation, impacts to aquatic and riparian habitat associated with agricultural practices, and increased

siltation Siltation, is water pollution caused by particulate Terrestrial ecoregion, terrestrial Clastic rock, clastic material, with a particle size dominated by silt or clay. It refers both to the increased concentration of suspended sediments and to the ...

and aquatic vegetation.

Life history

Central stonerollers reach maturity in one to four years. Breeding males begin building nests in late winter and continue throughout midsummer, creating large, bowl-shaped depressions in calmer waters by rolling stones along the bottom with their noses, giving them their common name. The males aggressively defend their nests against rival males.

Spawning Spawn is the eggs and sperm released or deposited into water by aquatic animals. As a verb, ''to spawn'' refers to the process of releasing the eggs and sperm, and the act of both sexes is called spawning. Most aquatic animals, except for aquat ...

occurs in early spring and summer, varying by region, with those fish in warmer climates generally spawning earlier than those in colder climates. Females remain in deeper water outside the nesting site, entering only briefly to produce anywhere between 200 and 4800 eggs in a nest.Baxter, G.T. 1955. A study of the fish population in Lodgepole Creek, Laramie County, Wyoming. J. Colo.-Wyo. Acad. Sci. IV (7):61. The male fertilizes the eggs, causing them to become adhesive and lodge in the gravel of the nest, preventing them from being carried away by the currents. The eggs are then abandoned by both parents and hatch within a few days. The newly hatched fish school together to feed in the warmer and more protected backwaters and vegetated stream margins. This species is generally found in small, clear streams with gravel, rubble, or exposed bedrock. Often the most abundant species in small streams, schools may contain several hundred individuals. Central stonerollers also display some intolerance to heavy

pollutants A pollutant or novel entity is a substance or energy introduced into the environment that has undesired effects, or adversely affects the usefulness of a resource. These can be both naturally forming (i.e. minerals or extracted compounds like o ...

, which affect the quantity of available algae in pool and riffle habitats.

Management

The central stoneroller is widely distributed, so is not being threatened to a large extent, nor is it listed on any federal or state conservation lists. The central stoneroller is listed as "least concern" on the IUCN Red list as of October 2018.

References

* Evans-White, M. A., W. K. Dodds, and M. R. Whiles. 2003. Ecosystem significance of crayfishes and stonerollers in a prairie stream: functional differences between co-occurring ominivores. Journal of the North American Benthological Society 22:423–441.

External links

* Photograph o
breeding tuburcles
by Tyler Goodale.
Photograph of ''Campostoma anomalum''
by Noel M. Burkhead. {{Taxonbar, from=Q8261255 Campostoma Fish described in 1820 Freshwater fish of North America Taxa named by Constantine Samuel Rafinesque