Tips for Higher Catfish Survival Rates

Organized bass tournaments started in the 1960s. Organized walleye tournaments soon followed. Then crappie tournaments. Why not catfish tournaments? Indeed, catfish tournaments are now part of the catfish fishing scene, and the numbers of tournaments appear to be growing. The tournaments span a continuum from local social group or company outings to large, heavily sponsored tournament trails. Many tournaments are family oriented, some are benefit centered with proceeds going to a charitable cause, and others are professional events with substantial payouts to participants. Almost all are judged by the weight of fish caught and usually only live fish are weighed. From both competitive and conservation perspectives, ensuring the release of live and healthy catfish is critical.

A Little Background

Bass tournaments began to grow in the late 1970s and early 1980s. It was a contentious early growth period with many anglers and some biologists fearing that the increasing tournaments would decimate bass populations. Others saw competitive fishing as an opportunity to grow fishing, the number of anglers, the sportfishing industry, and the importance of fisheries management, and maybe even provide data that would be useful to maintaining healthy fishery resources.

Along the way, catch and release became an obvious need. Live-release tournaments were a way to conserve a valuable resource and avoid the hideous sight of dead, floating bass after a tournament weigh-in, a situation that would make future tournaments unwanted guests at an access site. Improvements in bass boat livewells and five decades of research and trial-and-error learning have led to the development of livewell management and fish-handling practices that now consistently achieve greater than 90 percent survival of tournament-caught bass. Even though more than 32,000 bass tournaments occur annually, fisheries administrators now report rare or no impacts of tournaments on bass populations, a situation largely attributable to the development and implementation of effective live-release practices.

So what does this have to do with catfish? As was the case in the early days of bass tournaments, there probably are anglers and maybe a few fishery biologists who fear adverse effects of tournaments on catfish populations. But as has been found for bass, tournaments are unlikely to affect catfish populations adversely if tournament anglers and organizations use effective live-release procedures.

The recommended procedures for achieving high survival of tournament-caught bass (bassmaster.com/sites/default/files/keepingbassalive_guidebook_comp.pdf) provides procedures that can be used to ensure high survival of tournament-caught catfish in a variety of tournament conditions, but guidelines for care of catfish can be much simpler in most tournament scenarios.

The simpler approach recommended below recognizes the need for much larger livewells to accommodate fish that often exceed 50 pounds and differences between where bass and catfish anglers fish. Bass anglers fish in diverse environments, ranging from stagnant backwaters and areas of dense aquatic vegetation to main-lake basins. Catfish, with rare exceptions, are caught in flowing-water rivers or the open waters of lakes and reservoirs, environments that generally provide good water to fill and flush a livewell. These recommendations apply to anglers who can maintain their catch in a livewell that can be flushed with lake or river water and in which the water can be recirculated.

DIY Catfish Livewell

Big catfish need big livewells. Some tournaments require contestants’ boats to have at least a 50-gallon livewell capacity. If you fish tournaments where you may catch big catfish or in tournaments that require a high livewell volume, but your boat does not have at least a 50-gallon livewell, it’s time to add one. Several companies make complete, ready-to-use, large-volume bait tanks that work well for catfish. Aluminum truck tool boxes and plastic stock watering tanks make excellent livewells that have sufficient volume and stand up to the abuse that bruiser catfish can inflict on a livewell. Descriptions of DIY livewells on YouTube will give you some ideas. A few considerations in addition to what you will find on the Internet:

• Mount all plumbing and wires outside the livewell.
• Use separate pumps for filling and flushing the livewell and for recirculating water within the livewell. Pumps should deliver at least 500 gallons per hour.
• Install a filter or screen over the intake for the recirculating pump to prevent regurgitated stomach contents from clogging the pump.
• Spray water into the livewell from an open pipe or through a large hole or notch in an end cap that causes a lot of splashing and a large surface area of water exposed to air. A bunch of small holes in a pipe that drip water accomplish little aeration and quickly clog.
• Insulate the livewell lid and walls.
• Install the livewell crosswise in the boat (so the long dimension of the livewell is perpendicular to the boat centerline) to minimize sloshing that could injure the fish (and jeopardize boat control).

Practical LiveWell Management

Catfish, as all fish, need three conditions to survive in a livewell: water temperatures below their upper lethal tolerance level, adequate dissolved oxygen, and other water-quality parameters well below lethal tolerances.

Channel catfish tolerate long-term exposure to 91°F water; tolerances of blue catfish and flathead catfishes probably are similar. Surface water temperature exceeding 91°F is rare in lakes and rivers where catfish are caught. It is possible that catfish can be caught from cooler water below a thermocline, but this would only occur during early summer soon after a lake or reservoir stratifies (a time when surface water is cool, too), because the waters where catfish thrive tend to be fertile and productive, conditions that quickly deplete oxygen in the water below the thermocline. Flowing waters are the same temperature throughout the water column. Thus, surface water temperature is rarely a problem, and this water can be used to fill and flush a livewell.

Dissolved oxygen is essential for survival. Ensuring adequate oxygen is difficult because you can’t see it, and measuring it requires an expensive oxygen meter. When fish show signs of oxygen depletion, like trying to gulp air at the surface, it’s too late to recover them. And fish exposed even briefly to low oxygen may die several hours after release. The solution is to provide the maximum amount of aeration possible. The water, especially surface waters, where catfish are caught usually contains adequate dissolved oxygen for catfish survival, but catfish in a livewell will deplete the oxygen. The rate of oxygen depletion increases with the number and weight of fish in the livewell and temperature. Therefore, it is necessary to add fresh oxygen-containing water. This is accomplished by pumping fresh lake or river water into the livewell. The pump should deliver at least 500 gallons per hour.

The livewell water can’t have too much oxygen. The surface waters will contain oxygen, but you can add more oxygen by maximizing the exposure of the water to air as it enters the livewell. The water entering the livewell should flow out the end of a pipe or open nozzle causing as much splashing against the livewell wall or jetting into the livewell water as possible. This aeration system becomes the only source of aeration when the livewell is operated in recirculated mode when the boat is moved at high speeds or the boat is in a marina or other location where good-quality water may not be available for flow-through aeration. Whether flushing outside water or recirculating water, run the livewell pump continuously when fish are in the livewell.

In-line venturi systems such as Dannco, T-H Marine Max-Air, or Xtreme Oxygen Box (­xtremebaittanks.com) increase the efficiency of pumped-­water aeration. An oxygen infusion system (injecting pure oxygen into the livewell; see slideshare.net/raminlandfish/livewell-oxygen‑­injection-8773301) with a micropore air stone is a good addition to a livewell if you expect to have a heavy weight of catfish in the livewell during summer tournaments. Pumped-water aeration should be used with oxygen infusion systems to prevent supersaturation of oxygen. A study by Texas Parks and Wildlife Department has found oxygen generators (Oxygenator) add only a small amount of oxygen compared to pumped-­water aeration and should only be used to supplement pumped-water aeration. Anglers should be aware that oxygen generators can produce toxic chlorine gas from saltwater or livewell additives containing salt.

A long list of chemicals in water can affect catfish survival, but the only two of concern for fish in a livewell are ammonia and carbon dioxide. Both are products of metabolism and increase in a livewell. Ammonia and carbon dioxide are removed by flushing the livewell with outside water. Carbon dioxide, which can accumulate in the air space above the water and reduce the efficiency of pumped-water aeration, is easily removed by venting the livewell lid with a New Pro Products V-T2 Livewell Ventilator (newproproducts.com) or occasionally opening the livewell lid to allow the carbon dioxide-rich air to escape and fresh oxygen-rich air to enter.

A variety of commercial livewell additives are available. Maintaining adequate oxygen in livewell water is essential to keep catfish alive and facilitate their recovery from the stress of capture. None of the additives add oxygen to the water.

Flushing the livewell is necessary to prevent accumulation of ammonia. Maintaining label-recommended concentrations of livewell additives is impossible with continuous livewell flushing to aerate the water and remove ammonia.

From Catch to Release & Beyond: Simple Procedures to Ensure Catfish Survival

Proper livewell operation to provide oxygen and good water quality is essential, but there are some simple things that also help ensure that the catfish you release are still alive weeks and months after release.

• Protect the slime coat: Mucus is the catfish’s first line of defense against pathogens. 
• Use a smooth woven mesh or rubber mesh landing net.
• Don’t let fish flop on the boat deck or floor.
• Don’t put fish in a dry livewell.
• Minimize hook-removal injury. Use pliers to aid quick and safe hook removal with minimum tissue damage. A jaw-clamping fish gripper that doesn’t tear tissue helps to control fish.
• Minimize air exposure. Fish gills take up oxygen only when the thin gill filaments are separated by water. Air exposure can suffocate a fish.
• If culling is allowed, use culling clips that clamp over a fish’s jaw. Don’t use clips that pierce the mouth tissue. Don’t lift fish by the culling rope.
• The weigh-in can present situations that force you to adapt.
• Switch your livewell to recirculate water when in a marina or on the trailer waiting to weigh your catch.
• Minimize time fish are out of aerated water.
• Carry small catfish in a bag filled with livewell water and get fresh aerated water flowing into the bag as soon as possible while waiting to weigh your fish.
• Carry catfish too large for a weigh-in bag in a sling and immerse the sling and fish in aerated water immediately.
• If the tournament organizer does not provide aerated water in waiting tanks, wait until no other contestants are waiting to weigh in to fill your bag and bring your fish to the scales.

*Dr. Hal Schramm is a fishery scientist and regular contributor to In-Fisherman publications. He has conducted research on tournament mortality of black bass and other species, and is co-author of the popular publication Keeping Bass Alive: Guidebook for Anglers and Tournament Organizers.

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