The Brown Bullhead is a bottom dwelling fish, and prefers the slow-moving water of creeks, rivers, ponds, lakes, and reservoirs. They like to be around vegetation, and will eat almost anything that they come across including plants, zooplankton, and insects like mayfly larvae and caddisfly larvae as young, and small fish, mollusks, leeches, worms, crayfish, fish eggs, plants, and insects as adults. The Brown Bullhead has predators too. These include muskellunge, walleye, water snakes, green herons, northern pike, and snapping turtles. The most common predators of the bullheads eggs are shiner minnows, yellow perch, bluntnose minnows, and sunfishes.
Mating occurs during the spring or early summer. The female, or sometimes both the male and female, will build a nest by digging a hole in mud, sand, gravel, under roots, and sometimes under the shelter of logs and vegetation in shallow water. During nest construction, males are extremely territorial and will defend the nest and land around it. After the nest is constructed, the female will lie from 50 to 10,000 eggs, and the male will fertilize them externally. The eggs are then guarded by either one, or both of the parent fish. After about 5 days, the eggs will hatch and the male will typically take care of the young fish, and for 29 days, the male, and rarely the female, will chase away other fish who come to close to the nest. Both male and female bullheads become sexually mature at 3 years old. On average, the Bullhead will live for 6 to 8 years, and will reach a length of 8 to 12 inches, and a weight of about one pound.
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