Catfish Water Temperature: When Channels, Blues and Flatheads Bite

Catfish feed hardest in water of 75–85 °F (24–29 °C), and that one range covers channel, blue and flathead catfish alike. The three species part ways at the cold end and in the spawn. A channel catfish quits eating near 50 °F (10 °C), a flathead barely eats below 43 °F (6 °C), and a blue catfish keeps biting through the coldest month of the year. Below: the three numbers for each species, a band-by-band table, the spring start, the spawn lull, the cold cutoffs and the winter bank. The full chart for 25 species is on the water temperature chart.

Channel catfish stop feeding near 50 °F (10 °C), flatheads shut down at 43 °F (6 °C), and blue catfish bite all winter. Winter catfishing is a blue-cat game.

Three numbers for each catfish

A catfish is cold-blooded, so its appetite tracks the water. Metabolic rate roughly doubles with every 18 °F (10 °C) of warming and halves with every 18 °F of cooling (Clarke and Johnston 1999). A channel cat at 60 °F (16 °C) needs about half the food it needs at 78 °F (26 °C).

The aquaculture research on the channel catfish is the most precise. Growth is best at about 85 °F (29 °C), slow below 65 °F (18 °C), and feeding stops below about 50 °F (10 °C). Channel cats survive from just above freezing to nearly 100 °F (38 °C), so the fish are there in winter; they just do not eat. Texas Parks and Wildlife puts the spawn at 75 °F (24 °C); the aquaculture literature gives 75–85 °F (24–29 °C), optimum near 80 °F (27 °C).

The blue catfish spawns cooler. Virginia’s wildlife agency records blues moving to spawning areas at 70–75 °F (21–24 °C), Oklahoma says 75 °F (24 °C). No agency publishes a cold cutoff for blues, because there is not much of one. The anglers’ rule of thumb is that they slow below 55 °F (13 °C), and the guides catch the biggest fish of the year from November to March.

The flathead catfish is the true warm-water fish of the three. Texas puts its spawn at 75–80 °F (24–27 °C), Minnesota at 72–75 °F (22–24 °C). Wisconsin’s catfish management plan records flatheads feeding most actively above 50 °F (10 °C) and little or not at all below 43 °F (6 °C). They tolerate water in the low 90s. Bullheads sit with the flathead: comfort at 75–85 °F, spawn at 70–77 °F (21–25 °C), stress above 90 °F (32 °C).

Band by band: where each catfish is and how to fish it

The bands below are water temperature, taken where the bait will sit, not the air and not the surface. Southern reservoirs run through the sequence a month or two ahead of northern rivers.

When catfish start biting in spring

The spring question has three answers, one per species. Blue catfish never stopped. Channel catfish show as the water climbs through the 50s and become reliable once it holds above 65 °F (18 °C). The pre-spawn weeks at 70–75 °F (21–24 °C) are the easiest channel-cat fishing of the year. Flatheads join from 50 °F (10 °C) and feed hardest in the 60s and low 70s before the spawn.

“Do catfish bite in 50-degree weather” is a question about air, and catfish live in water. Water lags air by days to weeks. A week of 50-degree afternoons in March leaves most water in the 40s: blue-cat water, and channel water only in a river where the fish stack in the deep holes. The same 50-degree afternoon in October sits over water still in the 60s, and every catfish in the lake is eating. Read the water, not the forecast.

Two more rules. A warming trend beats a stable higher reading: three warming days at 52 °F (11 °C) fish better than a flat 58 °F (14 °C) after a cold front. And take the reading at the fish: a shallow spring bay warms 5–8 °F (3–4 °C) between dawn and mid-afternoon, and a summer lake can be 82 °F (28 °C) on top and 60 °F (16 °C) at 15 ft (4.6 m).

The spawn lull

Channel catfish spawn when the water reaches about 75 °F (24 °C), late May into July, in a cavity the male guards. Texas Parks and Wildlife has the eggs hatching in about a week and the fry staying in the nest another week. A nesting male is off the feed for two weeks or more, and the anchored bait in the usual hole goes quiet. That is the lull, and it is temperature, not weather or moon.

The fix is to fish the fish that are not in the nest. A slip float holding a bait just off the bottom along a rocky bank in 2–6 ft (0.6–1.8 m) finds the males between nests and the females that have finished. Blue catfish spawn a few degrees earlier, at 70–75 °F, and the spawn month is the one time the guides switch from cut bait to live shad. Flatheads follow at 72–80 °F (22–27 °C); a flathead guarding a hollow log is the fish the noodlers pull out by hand.

When catfish stop biting, and the winter bank

Channel catfish feeding ends near 50 °F (10 °C), and the fall bite fades as the water falls through the 50s in October and November. Flatheads go earlier: below 50 °F they feed little, below 43 °F (6 °C) hardly at all. The September and October feed before that is the best flathead fishing of the year. Blue catfish slow below 55 °F (13 °C) but never stop. The month-by-month calendar on the blue catfish page, from a Tennessee River guide, starts in January at 36–38 °F (2–3 °C).

So a winter catfish trip is a blue-cat trip, and it can be fished from the bank. Look for the deepest water reachable from shore: the outside of a river bend where the bank drops steeply, the tailrace below a dam, a bridge hole, a creek mouth in high water. Fish the afternoon after two or three sunny days. Anchor a slip-sinker rig with the lightest sinker that holds bottom, keep the leader short, and give a spot an hour. A river beats a lake in winter: current keeps the fish in predictable holes.

The cold-water bait is the one that runs all year for blues: fresh cut shad or skipjack herring, the oilier the better, hooked once through the skin with the point clear. Stink and punch baits are channel-cat baits for warm water; they sort for small fish and go stiff in the cold. For the few channel cats a cold river gives up, cut bait wins too, and a dip bait beats a punch bait; the best catfish bait page ranks them.

Reading the thermometer for catfish, step by step

1. Take the temperature where the bait will sit. A thermometer on a cord, lowered to the bottom of the hole, not the surface reading on the sonar. The two can differ by 20 °F (11 °C) in July.
2. Find the band in the table. Below 50 °F (10 °C) is blue-cat water; 50–70 °F (10–21 °C) is cut-bait water for all three as the feed builds; 70–85 °F (21–29 °C) is the spawn and the summer night bite.
3. Pick the species the band favors. In the 40s do not waste a night on flatheads; in the 70s the pre-spawn channel cats are the sure thing.
4. Pick the bait for the band. Cut shad below 60 °F (16 °C) and for every blue; punch or dip bait for channel numbers from 65 °F (18 °C) up; live bluegill for flatheads once the water passes 60 °F.
5. Pick the depth from the water, not the calendar. Cold water sends catfish to the deepest holes and mud bottoms; warming water pulls them onto the first flats that heat up; summer puts them deep by day and shallow at night.
6. Check the trend. Three warming days beat one warm one. After a cold front, fish deeper and slower for two days, whatever the reading says.
7. Time it. Afternoons in cold water, evenings in the 60s, full dark once the water is above 75 °F (24 °C).

The species profiles behind these numbers are on the catfish hub; the water temperature chart sets catfish beside the other species, 10 °F (6 °C) above the bass and 20 °F (11 °C) above the trout.