Perhaps one of the most easily identified and familiar fish is the catfish. This bottom-dwelling animal has a flat head, long slender barbels that resemble a cat's whiskers, and usually has "naked" or scaleless skin. The barbels are covered with many tastebuds and when food comes in contact with them a feeding response is triggered. Catfish rely more on taste and touch than they do on sight. They are active at night, on dark cloudy days, or in murky or muddy water. Catfish are omnivores, which means they will eat practically any kind of food. Catfish have a band of teeth on the roof of their mouths that point toward their throats, making it nearly impossible for prey to escape. When the dams release water, the levels can change drastically and allow food items through -- often sending the blue catfish into a feeding frenzy. Blue catfish are popular among seafood fans, and they are a target species for many sport and commercial fishermen. Catfish are not listed as a vulnerable species.