How to Tell If a Catfish Is a Male or Female
- 1). Look at the size of an adult catfish. A typical adult male catfish is smaller and narrower by about an inch.
- 2). Check the body width of the catfish. An adult female catfish is wider than an adult male catfish by 1 1/2 inches in the belly area. The female catfish is also rounder than the male catfish.
- 3). Analyze the size of the head of catfish. The adult male catfish will have the larger and wider head. The head of the male catfish can be up to 1 inch larger than the female.
- 4). Check out the dorsal fins. If the dorsal fins are long and brightly colored, you're looking at a male catfish.
- 5). Look at the openings on the catfish belly. Adult male and female catfish will have two openings at the lower belly, one for the anus and the other for the genitals. Male genitals are raised and shaped like a nipple. The female catfish genital area has an opening that is rounded. Right before spawning, the female genital area will be reddish and swollen.
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