The Diverse Diet of Catfish: From Small Fish to Algae

Catfish have long barbels that resemble a cat’s whiskers, which extend from the sides of their faces. There are close to 3,000 species of catfish, with the channel catfish being the most common. Most catfish live in freshwater, but there are some, like the hardhead catfish, that live in saltwater. So you might be wondering, do catfish eat mousefish? While it would be adorable if they did, they don’t. So then, what do catfish eat? Keep reading to take a deep dive into the murky waters of bottom feeders.

How Catfish Eat

As scavengers, catfish are always on the lookout for food. They seem to prefer fresh food, but will also eat dead animals or fish that are available. Catfish use the barbels on their faces to locate prey. The barbels have both taste and smell receptors to help them find food in the dark, muddy waters they inhabit.

What Catfish Eat

Catfish are opportunistic feeders, meaning they will adapt to the available food. Catfish eat a variety of small fish, mollusks, insects, crayfish, snails, clams, and frogs. They will eat algae and the remains of dead fish and plants that are floating in the water, when nothing better is available. Saltwater species, like the hardhead catfish, eat seagrass, sea cucumbers, shrimp, and blue crab. Other foods catfish eat are aquatic insects, algae, and phytoplankton.

Juvenile Diet

The diets of young and adult catfish do differ. In a study of channel catfish from Italy, researchers compared the diets of catfish and discovered that while male and female catfish have similar diets, juvenile catfish tend to eat smaller fare. The young ones fill up on phytoplankton and aquatic insects, while adults feast on a wider variety of larger foods.

Catfish Ecology

According the NOAA, one variety of catfish, the blue catfish, is considered an invasive species. In the Chesapeake Bay area, blue catfish are creating an imbalance in the food web. There are established workgroups addressing the issue and coming up with a plan to manage the blue catfish population in that area.

Catfish Predators

Does Crispy Southern Fried Catfish sound good to you? That’s because it is delicious. So it should come as no surprise that humans, along with crocodiles, birds of prey, and larger fish, prey on catfish — though they typically skip the Cajun seasoning!