Black Bullhead Catfish

Black Bullhead Catfish Habits

Development

After spawning, eggs hatch in 4 to 10 days. Free swimming fry remain close to the adult male for around two weeks. During this time the young reach around 25 mm in total length. Average growth is to 170 mm in the first year, 240 mm in the second year, 290 mm in the third year, 320 mm in the fourth year, peaking at around 350 mm total length by the fifth year. Sexual maturity is reached around 160 mm. Population density greatly affects black bullheads and sizes may vary greatly due to this.

Reproduction

After a female has constructed a nest, she intices a male by nudging the male's abdomen with her snout. After breeding, the pair lay side by side, with the male curling his caudal fin around the females mouth. After several pairings, spawning can be noticed by a quivering in the female. The female guards the nest for the first day, then the male takes over for the remainder of egg and fry protection.

Mating System

Mating System: monogamous

Spawning occurs between May and July. The female fans out a saucer shaped nest in a soft substrate, then removes larger elements with her snout. The male is nearby during the construction of the nest. Nests are typically in 2 to 4 feet of water and range in diameter and depth according to the substrate. On few occasions nest lay beneath a log or other forms of 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.

• Breeding interval: Black bullheads breed once yearly.
• Breeding season: Black bullheads breed from May to July.
• Range number of offspring: 2,000 to 3,800
• Average number of offspring: 3150
• Range time to hatching: 5 to 10 days
• Range time to independence: 12 to 17 days
• Average time to independence: 14 days
• Range age at sexual or reproductive maturity (female): 1 to 3 years
• Range age at sexual or reproductive maturity (male): 1 to 3 years

Prior to breeding, females construct a nest using pelvic and anal fins. After breeding the female guards the nest for the first day. After the first day males take over and guard the nest for up to 10 days until the eggs hatch. For the next two weeks the young remain close to the male.

Behavior

Adults are very inactive during daylight hours, feeding almost exclusively after dark, and are seldom seen or caught in rivers and streams until after dusk. Blacks bullheads tend to look for food after dark along with up to four others. No social systems have been observed.

• Key Behaviors: natatorial, nocturnal, crepuscular, motile, aestivation 

Parental Investment

• Pre-fertilization: provisioning protecting male female
• Pre-hatching/birth: provisioning male female protecting male female
• Pre-independence: provisioning male protecting male

Communication & Perception

Black bullheads have taste buds on in the mouth that help differentiate prey items. Barbels are used to pick up chemical and hydrodynamic cues left by prey. As in many catfishes the swim bladder is used to pick up on vibrations, as well as communicate.

• Communication Channels: visual, tactile, acoustic, chemical
• Perception Channels: visual, tactile, acoustic, chemical 

Food Habits

Young black bullheads usually thrive on ostracods, amphipods, copepods, and insects and their larva. Young feed primarily in schooling patterns during midday. Adults tend to be nocturnal, and feed on a wide variety of invertebrates. Midge larvae and other young insects are the primary diet for adult bullheads. Black bullheads have been known to eat small fish and fish eggs as well.

• Primary Diet: carnivore, insectivore, eats non-insect arthropods
• Animal Foods: fish eggs, carrion, insects, terrestrial worms, aquatic crustaceans
• Plant Foods: macroalgae
• Other Foods: detritus

Predation

Young black bullheads may fall prey to largemouth bass (Micropterus salmoides) and other basses, as well as walleye (Sander vitreus). They are protected from some predation by their venomous pectoral spines, that can inflict a painful sting.

• Known Predators: largemouth bass (Micropterus salmoides) other basses, walleye

Ecosystem Roles

Black bullheads raise turbidity levels in farm ponds. Because of this they can negatively affect other species which also inhabit the pond. Black bullheads can survive in muddy or turbid waters where many species do not thrive. Black bullheads are important intermediate predators in the ecosystems in which they live.

Economic Importance for Humans: Positive

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 when body size proportions are considered. Many black bullheads are kept in captivity because they adapt well and have a long lifespan.

• Positive Impacts: Pet trade food

Economic Importance for Humans: Negative

Black bullheads are not considered a problem to most humans. In some cases where overpopulation is a problem, they may never reach acceptable angling size. Where stocked in Europe, most populations are too dense to reach full size capacity, which makes them generally an unpopular species. Black bullheads can cause a painful sting if pectoral spines puncture human flesh. Black bullheads contain small amounts of venom at the ends of spine which can cause pain for up to a week.

• Negative Impacts: injures humans, venomous