This week’s Fish Fry Day – our series of posts featuring fish of Wisconsin – is taking a Southern twist! While catfish is a common menu item down south, it’s uncommon to find the tasty cornmeal-battered fillets offered in Wisconsin. In most of the state, fishermen tend to avoid catfish except for along the Mississippi River and its major tributaries, where they’re fished commercially.
Most people find catfish rather ugly. Between the slimy skin, creepy whiskers, and weird gaping mouths, it’s difficult to find much to like. Though they don’t exactly fit our aesthetic preferences, they’re well-suited for life on the river bottom. Unlike most fish, which are flattened vertically to cut through the water, catfish are “dorso-laterally compressed,” as fish biologists say, with a flat shape that allows them to settle near the substrate, where their dark coloration blends in with the bottom.
If a predator did manage to get a bite, the skin is coated in unpalatable mucus, and the dorsal fin has a sharp spine. Though catfish lack venom, anglers who accidentally poke themselves on these fish tend to get infections from the mucus.
The funny ‘whiskers’ for which catfish are named are also called barbels, and have chemosensory receptors that pick up scent molecules in the water, like our noses do in the air. Catfish are opportunistic omnivores, and their ungainly mouths can fit most food items they come across.
While the catfish might not be a contender in any underwater beauty pageants, its adaptations make it a winner in the natural selection race.
