Channel Catfish: ID, Size, Spines, Eating and Ponds

• Barbels (whiskers): Like our other catfish, channel catfish have smooth, scaleless skin and barbels ("whiskers") around the mouth.
• Tail shape: The tail fin is deeply forked; both the channel catfish and the blue catfish have a deeply forked tail.
• Anal fin shape: The outer margin of the anal fin is rounded outward (convex) rather than straight.
• Anal fin ray count: The anal fin usually has 24-29 rays, fewer than in the blue catfish.
• Body markings: It has scattered dark spots on the back and sides, though the spots are often absent in the smallest young and in large adults.
• Body shape: The profile of the back, from the dorsal fin forward, is gently sloping and slightly rounded outward, so the head and forward part of the body are less distinctly wedge-shaped than in the blue catfish.

The blue catfish never has dark spots on the back and sides, has a straight-edged (not rounded) anal fin with more rays (30-35) and a relatively longer base, and has a more distinctly wedge-shaped body profile. See the Blue Catfish page for its full mark list.

A freshwater fish found in a variety of habitats, but especially characteristic of large, rather turbid streams with low to moderate gradients; adults are mostly found around larger, deeper pools or submerged logs. Native to the St. Lawrence-Great Lakes, Hudson Bay (Red River drainage), and Missouri-Mississippi River basins, from southern Quebec, southern Manitoba, and Montana south to the Gulf Coast.

Lay the fish flat on its side in even light and photograph the whole body first, then the details below. Spread the tail fin so its shape (forked, rounded or square) is clear. Get a close, sharp frame of the head: mouth, jaw length and any barbels. Raise the dorsal and anal fins fully; ray counts and fin edges only read when the fin is spread. Shoot the side of the body before the fish dries; spots and stripes fade fast out of water. The app reads the photo and names the likely species; use the marks on this page to confirm it.

Size and daily limits for this species differ by state and by water, and some waters are catch-and-release only. Check the current regulations for where you are fishing before keeping any fish; if you are unsure of the species, release it.

Their fin spines are, mildly; their whiskers are not. Wikipedia says channel catfish have sharp spines on the pectoral and dorsal fins that inject venom and can cause injury. It also says the barbels, the "whiskers", cannot sting at all, which is a common misconception.

How serious is it? Wikipedia compares a channel catfish sting to a mosquito sting in danger, and notes that as many as half of all catfish species may be venomous, with venom made by gland cells covering the spines. The practical problem is usually a painful puncture wound.

To avoid it, keep your palms clear of the pectoral and dorsal spines when you hold or unhook the fish. If you are stung, wash the wound. See a doctor if the pain is severe, if swelling or redness spreads, if a piece of spine may be left in the wound, or if you develop a fever.

Yes; it is the catfish most Americans eat. Texas Parks and Wildlife says channel catfish are popular with anglers partly because of their flavour when cooked, and the Missouri Department of Conservation calls it one of Missouri's most highly prized game and food fishes.

Most of what is sold is farmed. Wikipedia says catfish is the largest aquaculture industry in the US, that channel catfish make up 90% of farm-raised catfish, that Mississippi produces over half of it, and that the southeast accounts for 94%.

For wild fish, check your state's consumption advisory for the lake or river you fished; larger, older fish from some waters carry more contaminants.

There is no single "regular catfish". Catfish is an order, Siluriformes, with about 36 families and more than 3,000 species (Wikipedia, 2007 count). The channel catfish is one species in the North American family Ictaluridae, and it is the default catfish of US farms and restaurants.

Two practical points:

• At the shop: Wikipedia says only fish of the family Ictaluridae may legally be marketed as catfish in the US. Vietnamese Pangasius is sold as basa, swai or river cobbler instead
• On the water: the channel catfish is most often confused with the blue catfish and the flathead catfish. The marks above separate them: channel catfish have a rounded anal fin with 24 to 29 rays and, in most sizes, dark spots

Size is not a reliable test. The North American record channel catfish weighed 58 pounds, caught in South Carolina in 1964 (Wikipedia; Texas Parks and Wildlife gives the same 58 lb record), while Wikipedia gives average adults at 2 to 4 pounds.

They are a common and hardy choice, with one catch: they rarely breed in ponds without help. Texas A&M's Department of Rangeland, Wildlife and Fisheries Management gives this guidance:

• Stocking rate: up to 50 fish per acre
• Size at stocking: usually 6 to 8 inches
• Reproduction: they do not naturally spawn in ponds; structures such as milk crates or buckets on the bottom can encourage spawning. Otherwise plan to restock
• Feeding: they can be fed pellets or left to live on the pond's natural food
• Growth: usually one pound by 2 to 4 years old
• Before stocking: talk to an extension specialist to check the pond suits them

The reason they need nesting structures is their breeding habit. Texas Parks and Wildlife and the Missouri Department of Conservation both describe channel catfish as cavity nesters that spawn when water reaches about 75 F, with the male choosing and guarding a dark, sheltered nest such as a hollow log or undercut bank.

The Missouri Department of Conservation describes the cycle: spawning runs from late May to mid-July; the male cleans the nest; the eggs sit in a gelatinous golden mass that looks like tapioca and hatch in about a week. Texas Parks and Wildlife adds that the fry stay under the male's care for about another week, and that a disturbed male may eat some of the eggs.

Channel catfish usually live no more than 6 or 7 years, though some pass 10, and they mature at about 4 to 5 years old and 12 to 15 inches (Missouri Department of Conservation).

They hunt largely by taste. MDC calls the channel catfish a "swimming tongue", with taste receptors across the body and barbels, and Wikipedia says it can detect some amino acids at about one part per 100 million in water. It is the state fish of Missouri (since 1997), Kansas, Iowa, Nebraska and Tennessee (MDC).