Snail bullhead

The snail bullhead grows to adult ranges approximately 11.4 inches (294mm) in perfect habitat and up to 17 inches (443mm) in disturbed habitats, such as reservoirs and impounded rivers.[4] The fish has a has a flat head, typical of North American ictalurids, eight maxillary mouth barbels, rounded anal fin, emarginate tail, two pectoral fins, adipose fin and a body lacking scales. Unlike a similar species, flathead catfish (Pylodictis olivaris) the anal fin has twenty or fewer fin rays. They also have three spines, one on the dorsal and two on the pectorals, that are coated with a toxic irritant used to ward off predators that causes pain and swelling of the inflicted area.[5] This species of fish can vary greatly in color morphs but the most commonly observed are brown to yellow-green backs with mottled sides and a white belly.[4] It should also be noted that these fish are ectothermic, bilaterally symmetrical and nocturnal.

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 in Virginia along the Atlantic slope, down to the Altamaha River 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 Drainage.[4] Their range in Georgia includes Tennessee, Coosa, Chattahoochee, Flint, Satilla, Ocmulgee, Oconee, Altamaha, Ogeechee, and Savannah River basins.[5]

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 decreasing in coastal streams.[4] The largest abundance is in the Broad River Basin due to no introduced species.

The snail bullhead is a generalist with its habitat. It has been found in shallow, slow water and, preferred, deep, fast water.[4][5] They are found in riffles, runs and pools and streams, rivers and lakes.[4] 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.[5]

Little is known about to diet of snail bullheads with only a few studies ever being conducted.[3] They are known omnivorous benthic bottom feeders that use their barbels for taste, touch and reading electric currents due to their poor sight.[6] For their carnivorous tendencies, they eat invertebrates, like snails, crawfish and caddisflies, and fish, mainly cyprinids. For the herbivores, they are known to feast on filamentous algae and other plants, possibly due to indirect digestion from feasting on caddisfly larvae.[3][7] They are the only know Bullhead that has been documented to be herbivorous.[7] It is also noted in data that snail bullheads diet is the same their entire life indicated by size-growth charts.[7]

The snail bullhead may be a least concerned species,[8] but that doesn't mean it is safe. Their home range is decreasing due to a myriad of factors. The primary concern regarding snail bullhead's are the introduction of invasive species, in particular the flathead catfish. The flathead has been known to prey upon the snail bullhead[4][7] 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.[4] Flathead are so common due to efforts of people stocking rivers and streams with them as a local sportfish with unforeseen effects on native fauna.[9] Other invasive ictalurids, like the white catfish, have negative effects as well. As an invasive, they have been known to decrease populations of bullheads by 60% along with outcompeting other species of fish in the region.[10] Along with invasive predators, snail bullheads are threatened by sedimentation, hydrologic modification, impoundments, non-point source pollution and development.[4]

Conservation for the fish isn't essential right now due to the still abundant population. Any general effort towards aquaculture will benefit the fish. The only known rule is that they are beginning to be illegal to catch due to their decreasing numbers.[9]

• Bullhead catfish
• Flathead catfish
• Brown bullhead