Brown Bullhead Catfish Species Information

Brown Bullhead - Ameiurus nebulosus

The Brown Bullhead can be identified by the presence of strong barbs or serrations on the back edge of its pectoral spines, and pigmentation in the chin barbels. Like other members of the catfish family, brown bullheads are often abundant in water a little muddier and warmer than most other fish prefer. They can tolerate high water temperatures and low dissolved oxygen levels that would be lethal to most other game fish. Having a highly-developed sense of smell and touch, bullheads are well equipped to negotiate murky waters and find food. Average 8-12 inches. Can grow larger in quality populations.

Geographic Range

Brown bullhead are native to freshwater habitats in Canada and the United States from 25° to 54° north latitude. They are distributed in the Atlantic and Gulf Slope drainages, ranging from Nova Scotia and New Brunswick to Mobile Bay, Alabama, and in the Great Lakes, Hudson Bay, and Mississippi basins from Quebec west to southeast Saskatchewan and south to Louisiana. Brown bullhead have been introduced outside of this range, including countries of northern, western, and eastern Europe, the Middle East, New Zealand, Chile, and Puerto Rico (U.S.). They have also been introduced and well established in the western United States and British Columbia.

• Biogeographic Regions: Nearctic, introduced, native, palearctic introduced 

Physical Description

Brown bullhead look very similar to black bullhead (Ameiurus melas) and yellow bullhead (Ameiurus natalis). Brown bullhead are distinguished by 5 to 8 large, serrated teeth on their pectoral spines , mottled coloring on their trunk, lack of dark fin rays, and 11 to 15 gill rakers on their first gill arch. An occasional solid colored trunk has been described. They have 8 dark brown to black barbels on their head (two nasal, two maxillary, and four on the chin) which are sensitive to touch and chemical stimuli. The anterior portion of their body is thicker than the posterior portion. The body is scaleless with a brown to black dorsal side and a lighter ventral side. In captivity, this species loses pigmentation, becoming whitish. They have terminal mouths with a slightly longer upper jaw and a mouth filled with irregular rows of tiny teeth on both jaws. However, Baily et al. (2004) described their jaws as being equal. Their head is dorso-ventrally flattened. They have one dorsal fin, an adipose fin, and a caudal fin with a slightly indented fork. Typical adult length is 200 to 300 mm but they may reach up to 500 mm. Adults typically weigh 0.5 kg, but have been recorded at 3.6 kg. No significant difference has been found between male and female size.

• Range mass: 3.6 (high) kg/7.93 (high) lb
• Average mass: 0.5 kg/1.10 lb
• Range length: 500 (high) mm/19.69 (high) in
• Average length: 200-300 mm/7.85-11.8 in

Life Span

6 - 8 years

Habitat

Brown bullhead are found in pools and slower-moving runs of creeks and rivers, reservoirs, ponds, and lakes. They are tolerant of a wide range of environmental conditions, including water temperatures up to 36 degrees Celsius and oxygen levels to 0.2 ppm. They prefer habitats with vegetation and substrate. They survive well in domestically and industrially polluted waters. They are bottom dwelling fish.

• Habitat Regions: temperate, tropical, freshwater
• Aquatic Biomesbenthic: lakes and ponds rivers and streams brackish water

Lifespan/Longevity

Brown bullhead live 6 to 8 years. Maximum age of brown bullhead is 9 years. Predation pressure is strongest during the egg and larval stages.

• Range lifespan Status: wild 9 (high) years
• Average lifespan Status: wild 6 to 8 years

Conservation Status

Brown bullhead are not listed for protection under the IUCN Red List, the United States Endangered Species Program, or under a CITES appendix. (International Union for Conservation of Nature and Natural Resources, 2009; U.S. Fish & Wildlife Service, 2010; United Nations Environment Programme and World Conservation Monitoring Centre, 2010)

Similar species

• The Black Bullhead, A. melas lacks dark mottling and spots on the side of the body and has no large sawlike teeth on the rear edge of the pectoral spine. It has 15-21 rakers on the first gill arch, and the anal and caudal fins have strongly contrasting rays (pale) and membranes (black).
• The Yellow Bullhead, A. natalis, lacks mottling or dark spots on the side of the body, has white or yellow chin barbels and more anal rays (24-27).