Black bullheads are distinguished from other, similar bullhead catfish by their very broad head and their long, dark "whiskers." These "whiskers" are known as barbels and are used to feel and taste their environment. They are dark brown to black on their top surface and yellowish or white on their undersides. Their fins are black and the tail fin is rounded, sometimes with a pale stripe at its base. Similar species include yellow bullheads,and brown bullheads. However, black bullheads are the only bullhead species with completely dark "whiskers." Yellow bullheads have no color on their "whiskers" and brown bullheads have light color on the ends of the "whiskers."
The native range of black bullheads extends west from the Appalachian mountain range to Arizona, north to southern Canada, and as far north and east as New York. They can be found as far south as northern Mexico and Florida. Black bullheads have been introduced to parts of California and Nevada. They have also been introduced to parts of England.
Black bullheads are found in most freshwater habitats, from small farm ponds to large lakes. They can survive in water that other fish species cannot, including water that is polluted, has low levels of oxygen, is very warm, and has lots of suspended sediments (is turbid). Because they are relatively small fish, black bullheads can also live in small creeks and rivers. They prefer areas with soft bottoms (in creeks and rivers) and stay away from areas where the water is free flowing and moves quickly. They feed in waters that are from one to three meters deep.
After spawning, eggs hatch in 4 to 10 days. Free swimming fry stay close to the adult male for around two weeks. During this time the young grow to about 25 mm in total length. They reach a total of 100 mm by the end of the first year and reach a maximum of 350 mm by the time they are 5 years old. They can mate after one year of growth. Black bullheads grow faster and become larger when there are fewer, other black bullheads around. Crowded conditions lead to lower growth rates.
After a female has constructed a nest, she attracts a male by nudging the male's abdomen with her snout. The female will deposit eggs into the nest and the male deposits his sperm onto them afterwards. The female guards the nest for the first day, then the male takes over for the remainder of egg and fry protection.
Black bullheads spawn between May and July. The female makes a saucer shaped nest in soft substrate, like silt or mud. She removes rocks and other debris with her snout. The male is nearby during her construction of the nest. Nests are usually in 2 to 4 feet of water. Sometimes nests are beneath a log or other structure. Females produce between 2,000 and 3,800 eggs. Spawning occurs five times over a one hour period. The male watches over the nest after the first day for up to ten days. When the eggs then hatch, they stay close to the male for up to two weeks.
Before breeding, females construct a nest using their fins. After breeding the female guards the nest for the first day, then the male takes over for up to 10 days until the eggs hatch. For the next two weeks the young remain close to the male.
Black bullheads live about five years in the wild and slightly longer in captivity. The oldest are around ten years old. They are easily kept in aquariums and adapt well to captivity.
Adults are not very active during the day, they feed mostly after dark, and are seldom seen or caught in rivers and streams until after dusk. Blacks bullheads tend to look for food along with small groups of other black bullheads.
Little is known about the size of the home range in black bullheads. They tend to utilize pools in rivers and occupy areas where food is available. ("A Boundary Waters Compendium", 2004)
Black bullheads have taste buds on in the mouth that help differentiate prey items. Barbels are used to pick up chemicals in the water and water movements. As in many catfishes the swim bladder is used to pick up on vibrations, as well as communicate.
Young black bullheads usually thrive on small crustaceans, like ostracods, amphipods, and copepods, as well as insects and their larva. Young feed in small schools during the middle of the day. Adults feed at night and eat on a wide variety of invertebrates. Midge larvae and other young insects are the main diet for adult bullheads. Black bullheads have been known to eat small fish and fish eggs as well. Black bullheads will also eat plant material and scavenge.
Young black bullheads may fall prey to largemouth bass and other basses, as well as walleye. They are protected from some predation by their venomous pectoral spines, that can inflict a painful sting.
Black bullheads can make the water in which they live more cloudy and turbid, making it difficult for other fish species to survive. Black bullheads are important intermediate predators in the ecosystems in which they live.
Black bullheads are not considered a problem to most humans. In areas where populations are very dense, they never grow to their maximum size, making them unpopular for fishing. Black bullheads can cause a painful sting with spines on their sides. Black bullheads contain small amounts of venom at the ends of these spines, which can cause pain for up to a week.
Though black bullheads are relatively small, they have become a popular fish among anglers. They are known for their good taste and amount of fight during a catch. Many black bullheads are kept in captivity because they adapt well and have a long lifespan.
Black bullheads are common and sometime very abundant throught their range. They have become a popular gamefish in many areas, so fishery agencies sometimes "stock" lakes and ponds with black bullheads for fishermen.
Tanya Dewey (editor), Animal Diversity Web.
Chris Rose (author), Eastern Kentucky University, Sherry Harrel (editor, instructor), Eastern Kentucky University.
2004. "A Boundary Waters Compendium" (On-line). Accessed October 31, 2005 at http://www.rook.org/earl/bwca/nature/fish/ictalurusmel.html.
Etnier, D., W. Starnes. 1993. The Fishes of Tennessee. The University of Tennessee Press/ Knoxville.