The Science Behind Trophy Blue Catfish — and Why Winter Is the Best Time to Catch Them

On a crisp winter morning in the mid-1980s, two men stepped into the Southwest (Oklahoma) Fisheries office to ask if we had some scales big enough to weigh their catfish. Everyone gathered outside to witness two of the biggest fish I’d ever seen from freshwater. Richard Hopper and Gerald High, two veteran catmen, had been juglining that cool February day on nearby Lake Lawtonka, and netted two huge blue cats.

At first, I didn’t know that little Lawtonka even held blue cats, much less any this big. The scale proved that each fish weighed over 50 pounds. Secondly, I didn’t know that catfish would bite in the winter, yet here hung the evidence of a potential trophy fishery. I took a picture of the guys and their blue cats, and the photo slide is still in a dusty file back at the office.

Usually, the only thing biting deep in an Oklahoma in winter are stocked trout or deep-water crappies. For a biologist, it’s a time to write reports, draft budgets, and plan projects for spring. But in December 1999, another angler came to the office to officially weigh an 85-pound blue catfish that set a (then) state record.

Of the several species in the Ictalurus genus, the blue catfish stands out in three important ways. Of course, there’s the potential for triple-digit weights that lures anglers to the sport. Then there’s the blue’s tolerance—or maybe even preference—for cold water, which makes them a potential year-round target. And finally, there’s a migratory tendency that makes the blue a truly different cat.

By understanding these three unique traits, anglers can increase their odds of finding big blue cats in reservoirs across the species’ expanding range, particularly in northern climates and during colder months in the South.

Sizing Them Up

Blue catfish are native to the Mississippi drainages, including the Ohio, Mississippi, Missouri, Tennessee, Arkansas, and Red rivers. Their native distribution ranges east to the Tombigbee River in Alabama, and west to the Gulf coastal rivers across Texas, from the Sabine to the Rio Grande.

Within that original range, many states boast fishing records over 100 pounds. Unofficial historic accounts of river-dwelling blue catfish exceed 200 pounds, and possibly more than 300. Kerr Lake in Virginia, where blue catfish were introduced, produced the current official world record of 143 pounds. As a freshwater trophy, only the alligator gar and sturgeon rival blue catfish.

In reviewing the list of state-record blue catfish, some also stand out for when they were hooked. The Texas state-record blue weighed 121.5 pounds, and it was caught from Lake Texoma in January 2004. The West Virginia rod-and-reel record of 69 pounds was caught in December of 2023. The South Carolina unofficial record blue cat of 136 pounds was caught on a trotline in February 2012.

In an In-Fisherman article from 2020, then-Field Editor Cory Schmidt told the story of two former North Carolina state record blues (91 and then 105 pounds) that were caught back-to-back, by the same angler, in December 2015. Schmidt further reported that “Likely the second largest [blue] catfish ever recorded on hook and line was a 141-pound 12-ounce, 61-inch monster caught by Dale Lowe Jr. at Kerr Reservoir in January 2017.”

Perhaps the reason even more monster blues aren’t caught in winter is the fact that it’s an off-season for most anglers. Record blues have been caught in every month, so the big ones are comfortable—and can be caught—in any season, including winter.

Cool Cats

Biologists classify fish species as either warmwater, coolwater, or coldwater. I studied and worked in the South as a warmwater specialist, but in Oklahoma we dabbled with trout (a coldwater species), and walleye (coolwater).

Catfish are generally considered warmwater fish, but anglers convinced me that blues were very active in winter. In fact, blue catting attracts an ardent core of wintertime anglers at several Oklahoma reservoirs like Texoma, Keystone, and Kaw. Smaller lakes like Waurika, Oolagah, and Hugo also produce huge blues in cold months.

At Lake Ellsworth in my former management region, a dedicated clan of specialists brave winter weather, fishing with surf rods from the bank for big blue cats. One of them is the Manning State Fish Hatchery manager Tyler Wright, who I worked with for several years.

Well into his career now, Wright is an expert at rearing fry and fingerling fish for stocking in Oklahoma lakes. In his spare time though, he chases big blue catfish, and winter is prime time for his bank or boat excursions.

“I started fishing for blues when I was about 12,” Wright says. “That’s when Ellsworth was taking off. My dad had fished Ellsworth back in the 1970s for flatheads. Back then they used livebait and willow bank poles at night. Surf poles back then were 6-foot ‘broom sticks’ with old Penn 9 reels.

“For blues now I like a 12-foot rod with an Abu Garcia 7000 reel, and I take two of the anti-backlash brakes out of the 7000s, so they cast farther. I like Berkley Big Game line—usually I use 30-pound test—with an Eagle Claw wide-bend 4/0 hook. Sometimes I use Gamakatsu circle hooks for boat-fishing with big baits.”

Luckily for Wright, his favorite season for blue catting coincides with the slower season at the fish hatchery. “Big blues are more active in the winter ,” he says. “I haven’t caught many big ones in the summer, but sunny fair-weather days have never been very good for big fish. Cold and windy days are best.”

For location, he likes to play the winter wind, which is often a challenge in Oklahoma. “Having deep water close by is always a plus, but most of the big fish I’ve caught have been in 10 feet of water or less,” he says. “Fishing into the wind is good, but catching the slack water around the backside of a windy point can be excellent. Flats can also be excellent on windy days. I’ve caught lots of big fish in 4 feet of water on windy, cold days.”

A wintertime rain can also be good for fishing, he says. “When water is running, blues usually bite. I like to fish flats when the water is dumping in.”

Wright collects shad from deep water using an 8-foot-radius cast net, getting a workout hauling 20 pounds of lead and shad back up after each throw.

“Bait is always hard to locate in winter, but the new fish finders are excellent tools for that,” he says. “The days of blindly throwing a net for hours and hours in the freezing cold are over.” 

Not every angler is cut out for blue catting in winter conditions, he says. “I’m not sure how many are still going after blues out there. In the 1990s, there were probably 10 to 15 of us chasing blues. We kept in communication with CB radios and knew when a big fish was caught.”

Wright believes that it’s harder now to catch a trophy blue. “There were lots of fish in the 30-pound range, with a few 40s and 50s being caught every so often,” he says. “As the use of juglines increased, the size of the fish decreased. Overfishing large blues was probably the main reason. It takes 10-plus years for a blue to get big.”

Still, he says it’s worth the effort. “I love winter fishing for blues. There’s very little activity around the lake. Some days I won’t see a single person, and it’s good stress relief.”

He often shares his catch by hosting popular fish fries at the hatchery. He’s always sure to cut the red meat out of a blue catfish fillet before cutting it up into bite-sized chunks. That red muscle points to the final key difference between blues and their related whiskered species.

Homers and Roamers

If you’ve cleaned a blue cat, you’ve seen the streak of red meat along the side of the fillets, along the lateral line. It’s the same strip of muscle found on a white bass or striped bass, two other highly mobile freshwater species.

In saltwater, tuna and salmon muscle is dominated by the red form because they spend most of their time moving. On the other end of the spectrum, sunfish have very little red muscle, since they’re less likely to swim long distances, and use ambush tactics to feed.

Red muscle is high in oxygen, and its function is slow, deliberate motion, the kind used during migration. In contrast, white muscle is suited to quick-burst propulsion. Red meat also contains more fatty tissue that concentrates fat-soluble compounds that give it a more intense, “fishy” flavor.

Channel catfish are known to establish a relatively restricted home range, and a flathead catfish might spend most of its lifetime in a single brushpile, with an occasional seasonal trip to a cavity for spawning. Red muscle is minimal in those catfish.

Like striped bass, blue catfish move daily and migrate seasonally, covering great distances in search of food and better habitat. Wandering blue catfish were once found to travel up to 400 miles in the Mississippi River, and they can cover over a mile per day.

In reservoirs, where travel is restricted downstream by dams, and shallow tributaries upstream, movement patterns are of course narrower, but also unpredictable. Several studies have examined the migratory habits and preferred winter habitats of blue cats.

At Lake Wilson in northern Alabama, biologists implanted a dozen blue catfish from 15 to 55 pounds with radio transmitters. They found that about half of the fish were “movers,” migrating downstream, and half were “homers” that remained in the tailrace where they were originally tagged.

Perhaps more telling was the fact that those blue catfish were more likely to move and moved farther as water temperatures fell. For most warmwater fish species, the opposite is true. Furthermore, the researchers state that, “When fish were located in downstream portions of Lake Wilson, they were always found near the bank or on submerged humps in shallow water.

“Water temperature appeared to be the most important factor related to blue catfish movement rates,” and “movement rates [at Lake Wilson] were greater at cooler water temperatures.”

In 2007, researchers at Lake Texoma radio-tagged 50 blues and found similar results. Some blues traveled far upstream in the Red River to find spring spawning sites and remained there in the summer, but some set up home ranges in the lower reservoir year-round. Lead researcher Cory Lee concluded, “My results suggest that blue catfish are more mobile in winter than had been previously thought.”

In Milford Reservoir, the largest man-made lake in Kansas, researchers from Kansas State University (KSU) ambitiously radio-tagged 123 blues and collected over a million “pings” over two years from their 20 receiver stations scattered around the reservoir. In this study, none of the tagged blues escaped upstream or down over the dam.

Dr. Martha Mather and KSU students describe blue catfish in Milford as both “consistent aggregators” (homers) and “seasonal movers” (roamers). The researchers reported a movement of fish to the lower end of the lake in the fall, but they didn’t track the blues in winter. They did find that blues preferred water with greater visibility (shallower water) and speculated that these sites held more shad that were feeding on phytoplankton. Blues also selected sites with higher slope, meaning that they concentrated near channels.

In 2001 at Lake Norman, North Carolina, 29 blues were implanted with transmitters. Researchers there said, “The data suggest that blue catfish may have segregated populations within Lake Norman, with one group traversing from the lower region to the upper region of the lake during the year, a second group remaining in the upper region year-round, and a third group remaining in the lower region year-round.”

In summary, the studies describe a potentially mobile species, with a wide range of habitat preferences to go along with its omnivorous diet. In fall, blues generally migrate downlake to deeper water, and they feed actively in winter.

Conservation Potential

Early in my career—like when Hopper and High stopped in to weigh their big catfish—nearly every decent-sized blue went home to be skinned for a fish fry. Nowadays, more and more anglers like Wright are taking a conservative approach, keeping the more abundant mid-sized blues and releasing the rare big ones.

In the 1990s, biologists learned how to sample blue catfish using electrofishing boats. In Oklahoma, we netted and measured thousands of them. Learning from those samples, we set harvest restrictions on big blues in hopes that more could reach their full trophy size potential. Several other states followed suit. Those management efforts continue to be evaluated and modified today.

Results from legal protection of big blue catfish are mixed so far. Scientists in Oklahoma, North Carolina, Alabama, and Missouri have studied length limits, and in some cases, they show promise, while others indicate no effect. For a fish that lives this long (and grows so slowly), another decade may be needed to know if laws are positively affecting the top end of populations.

Luckily, these days, with enough population data, researchers can use computer simulations (modeling) to predict the effects of regulations, rather than using the old trial-and-error method (at the possible expense of dissatisfied anglers).

Fishery researchers in Kansas conducted population modeling and found, “Blue Catfish populations in Kansas reservoirs exhibit different dynamics but demonstrate resilience to overfishing. The largest individuals in populations are much more vulnerable to angler catch than smaller fish, but the risk of overharvest appears mitigated by angler self‐regulation.”

With time and management attention, and catch and release of trophies, will some lake have the potential to produce a blue catfish over 200 pounds? Some speculate that it’s less likely because of impoundments and dams now blanketing the blue’s range, but I’d argue that it may be more likely for the same reason.

Dams tend to concentrate prey like shad, and impoundments offer prey-filled deep-water habitat in winter where blues can thrive. And the problematic introductions to the east and west open up new opportunities for trophy blues (perhaps at the expense of competing native species).

Blue catters themselves may ultimately be responsible for better fishing by voluntarily releasing more trophies to be caught again.

Longtime In-Fisherman contributor Larry Cofer is a retired fishery supervisor with the Oklahoma Department of Wildlife Conservation.

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