The snail bullhead (''Ameiurus brunneus'') is a

bony fish Osteichthyes ( ; ), also known as osteichthyans or commonly referred to as the bony fish, is a Biodiversity, diverse clade of vertebrate animals that have endoskeletons primarily composed of bone tissue. They can be contrasted with the Chondricht ...

in the family

Ictaluridae The Ictaluridae, sometimes called ictalurids, are a family of catfish native to North America, where they are an important food source and sometimes fished for sport. The family includes about 51 species, some commonly known as bullheads, madt ...

distributed widely in the southeastern United States. Among its

bullhead catfish ''Ameiurus'' is a genus of catfishes in the family Ictaluridae. It contains the three common types of bullhead catfish found in waters of the United States, the black bullhead (''Ameiurus melas''), the brown bullhead (''Ameiurus nebulosus''), a ...

congeners, it has many North American relatives, like the

brown bullhead The brown bullhead (''Ameiurus nebulosus'') is a fish of the family Ictaluridae that is widely distributed in North America. It is a species of bullhead catfish and is similar to the black bullhead (''Ameiurus melas'') and yellow bullhead (' ...

(''Ameiurus nebulosus'') and

black bullhead The black bullhead or black bullhead catfish (''Ameiurus melas'') is a species of Ameiurus, bullhead catfish. Like other bullhead catfish, it has the ability to thrive in waters that are low in oxygen, brackish, turbid, and/or very warm. It also ...

(''Ameirurus melas''). The species was described in 1877 by

David Starr Jordan David Starr Jordan (January 19, 1851 – September 19, 1931) was the founding president of Stanford University, serving from 1891 to 1913. He was an ichthyologist during his research career. Prior to serving as president of Stanford Universi ...

in the

Ocmulgee River The Ocmulgee River () is a western tributary of the Altamaha River, approximately 255 mi (410 km) long, in the U.S. state of Georgia (U.S. state), Georgia. It is the westernmost major tributary of the Altamaha. Little is known about this species of fish and it is not a particularly prized fish due to its small size. The only known alias is the general vernacular term for all

catfish Catfish (or catfishes; order (biology), order Siluriformes or Nematognathi) are a diverse group of ray-finned fish. Catfish are common name, named for their prominent barbel (anatomy), barbels, which resemble a cat's whiskers, though not ...

in the United States, "mudcat".

Description

NMNH-usnm 17861 Ameiurus brunneus lype xray lateral

The snail bullhead grows to an adult size of approximately in

fluvial A river is a natural stream of fresh water that flows on land or inside caves towards another body of water at a lower elevation, such as an ocean, lake, or another river. A river may run dry before reaching the end of its course if it ru ...

habitat and up to in disturbed habitats, such as reservoirs and impounded rivers. The fish has a has a flat head, typical of North American ictalurids, eight maxillary mouth

barbels In fish anatomy and turtle anatomy, a barbel is a slender, whisker like sensory organ near the mouth (sometimes called whiskers or tendrils). Fish that have barbels include the catfish, the carp, the goatfish, the hagfish, the sturgeon, the z ...

, a rounded anal fin, an

emarginate The following terms are used to describe leaf morphology in the description and taxonomy of plants. Leaves may be simple (that is, the leaf blade or 'lamina' is undivided) or compound (that is, the leaf blade is divided into two or more leaflets) ...

tail, two pectoral fins, an adipose fin and a body lacking scales. The

anal fin Fins are moving appendages protruding from the body of fish that interact with water to generate thrust and help the fish swim. Apart from the tail or caudal fin, fish fins have no direct connection with the back bone and are supported o ...

of ''A. brunneus'' typically has 17 to 20 fin rays, fewer than that of a related species, the flat bullhead (''A. platycephalus''), although some individuals may have as many as 22 rays. They also have three spines, one on the

dorsal Dorsal (from Latin ''dorsum'' ‘back’) may refer to: * Dorsal (anatomy), an anatomical term of location referring to the back or upper side of an organism or parts of an organism * Dorsal, positioned on top of an aircraft's fuselage The fus ...

and two on the

pectoral Pectoral may refer to: * The chest region and anything relating to it. * Pectoral cross, a cross worn on the chest * a decorative, usually jeweled version of a gorget * Pectoral (Ancient Egypt), a type of jewelry worn in ancient Egypt * Pectora ...

fins, which are coated with a toxic irritant that inflicts local pain and swelling as a defense against predation. The pectoral spines have fine serrations, but lack coarse teeth, which helps to distinguish snail bullheads from spotted bullheads (''A. serracanthus''). ''A. brunneus'' can vary greatly in color but the most commonly observed morphs have brown to yellow-green backs with mottled sides and a white belly. There is a dark spot or bar that colors the base of the dorsal fin. It should also be noted that these fish are

ectothermic An ectotherm (), more commonly referred to as a "cold-blooded animal", is an animal in which internal physiological sources of heat, such as blood, are of relatively small or of quite negligible importance in controlling body temperature.Daven ...

bilaterally symmetrical Symmetry in biology refers to the symmetry observed in organisms, including plants, animals, fungi, and bacteria. External symmetry can be easily seen by just looking at an organism. For example, the face of a human being has a plane of symme ...

and

nocturnal Nocturnality is a ethology, behavior in some non-human animals characterized by being active during the night and sleeping during the day. The common adjective is "nocturnal", versus diurnality, diurnal meaning the opposite. Nocturnal creatur ...

Distribution

The snail bullhead has a native range in the Southeast. They primarily occur from Virginia to Florida through Alabama. The uppermost portion of their range is along the

Dan River Dan River may refer to: * Dan River (Virginia) * Dan River (China) * Dan River (Middle East) Other * Little Dan River * Browns Dan River * Dan Hole River See also * Dan (disambiguation) Dan or DAN may refer to: People * Dan (name), inc ...

in Virginia along the Atlantic slope, down to the

Altamaha River The Altamaha River is a major river in the U.S. state of Georgia (U.S. state), Georgia. It flows generally eastward for from its Source (river or stream), origin at the confluence of the Oconee River and Ocmulgee River towards the Atlantic Oce ...

system in Georgia and ends at the St. John's River drainage in Florida. They also occur in the Gulf drainage such as

Apalachicola River The Apalachicola River is a river, approximately long, in the state of Florida. The river's large drainage basin, watershed, known as the ACF River Basin, Apalachicola, Chattahoochee and Flint (ACF) River Basin, drains an area of approximately ...

Drainage. Their range in Georgia includes

Tennessee Tennessee (, ), officially the State of Tennessee, is a landlocked U.S. state, state in the Southeastern United States, Southeastern region of the United States. It borders Kentucky to the north, Virginia to the northeast, North Carolina t ...

, Coosa,

Chattahoochee The Chattahoochee River () is a river in the Southeastern United States, Southeastern United States. It forms the southern half of the Alabama and Georgia (U.S. state), Georgia border, as well as a portion of the Florida and Georgia border. It ...

Flint Flint, occasionally flintstone, is a sedimentary cryptocrystalline form of the mineral quartz, categorized as the variety of chert that occurs in chalk or marly limestone. Historically, flint was widely used to make stone tools and start ...

, Satilla, Ocmulgee, Oconee, Altamaha, Ogeechee, and

Savannah River The Savannah River is a major river in the Southeastern United States, forming most of the border between the states of Georgia (U.S. state), Georgia and South Carolina. The river flows from the Appalachian Mountains to the Atlantic Ocean, ...

basins. The fish is relatively common in its home range. In South Carolina, they are most abundant in smaller streams in the upper Santee drainage but are more rare in coastal streams. The largest abundance is in the Broad River Basin due to absence of introduced species.

Habitat

The snail bullhead is a generalist with its habitat. It has been found in shallow, slow water and, preferred, deep, fast water. They are found in riffles, runs and pools and streams, rivers and lakes. As a nocturnal species, they prefer cover under rock and wood structures during the day and forage in the open at riffles at night. They prefer fast flowing water in high gradient streams due to the purity and clarity of the water but will also live in stagnant water.

Diet

Little is known about to diet of snail bullheads with only a few studies ever being conducted. They are known omnivorous benthic bottom feeders that use their barbels for taste, touch and reading electric currents due to their poor sight. They are predators of invertebrates, like

snails A snail is a shelled gastropod. The name is most often applied to land snails, terrestrial molluscs, terrestrial pulmonate gastropod molluscs. However, the common name ''snail'' is also used for most of the members of the molluscan class Gas ...

crayfish Crayfish are freshwater crustaceans belonging to the infraorder Astacidea, which also contains lobsters. Taxonomically, they are members of the superfamilies Astacoidea and Parastacoidea. They breathe through feather-like gills. Some spe ...

and

caddisflies The caddisflies (order Trichoptera) are a group of insects with aquatic larvae and terrestrial adults. There are approximately 14,500 described species, most of which can be divided into the suborders Integripalpia and Annulipalpia on the basis ...

, as well as other fish, mainly cyprinids. Additionally, they are believed to forage on filamentous algae and other plants, although these may be sourced indirectly from the ingestion of caddisfly larval cases. It has also been observed that the diet of snail bullheads has similar composition across the lifespan.

Conservation

The snail bullhead may currently be a species of "least concern", but that doesn't mean it is safe. Their home range is decreasing due to a myriad of factors. The primary concern for the snail bullhead is the introduction of invasive species, in particular the

flathead catfish The flathead catfish (''Pylodictis olivaris''), also called by several common names including mudcat or shovelhead cat, is a large species of North American freshwater catfish in the family Ictaluridae. It is the only species of the genus ''Py ...

(''Pylodictis olivaris''). The flathead has been known to prey upon the snail bullhead and greatly reduce populations in rivers. Flathead catfish also have a displacing effect on the snail bullhead by running them out of large rivers and confining them to smaller streams. Flathead catfish are common because people intentionally stock them into rivers and streams as a sportfish, with unforeseen effects on native fauna. Along with invasive predators, snail bullheads are threatened by

sedimentation Sedimentation is the deposition of sediments. It takes place when particles in suspension settle out of the fluid in which they are entrained and come to rest against a barrier. This is due to their motion through the fluid in response to th ...

, hydrologic modification, impoundments, non-point source pollution and development. An analysis of the population of snail bullheads and other ictalurids in the

Cape Fear River The Cape Fear River is a blackwater river in east-central North Carolina. It flows into the Atlantic Ocean near Cape Fear, from which it takes its name. The river is formed at the confluence of the Haw River and the Deep River in the town of ...

basin, published in 2021, supported previous recommendations that the harvest of snail bullheads, along with their native bullhead relatives, be restricted in North Carolina.

References

{{Taxonbar, from= Q943236 Ameiurus Freshwater fish of the Southeastern United States Taxa named by David Starr Jordan