Black Bullhead

Identification

The black bullhead is a small catfish species reaching 15 to 35 cm (maximum 66 cm) with a stocky, dark body. Color is uniformly dark brown to black without distinct markings. Characteristic are the eight barbels (four pairs), the broad, flattened head, and the stiff, serrated spines in the pectoral and dorsal fins. These spines can cause painful wounds if handled carelessly. The tail fin is straight-edged or slightly notched.

Behavior & ecology

The black bullhead is a nocturnal bottom-dweller that lives in still or slow-flowing water with muddy substrate. The species is exceptionally tolerant of poor water quality: low oxygen, high temperatures, and pollution are well tolerated. Diet consists of insect larvae, worms, small fish, and plant material. Males guard the nest and young — unusual behavior for a fish.

In the Netherlands

The black bullhead is a North American exotic introduced to Europe in the 19th century as an aquarium fish. 86 records exist in the Netherlands, scattered across the country. The species establishes itself mainly in heated waters near power plants and in shallow, warm ditches. As an invasive exotic it is on the watch list, but does not currently pose a major ecological problem in the Netherlands.