Summertime bass care

Temperature, oxygen and fresh water

It’s June and the waters where our sport fish live have warmed into the 80s. Although temperatures a little above 80 degrees approximate the preferred temperatures for bass, anglers intending to keep fish alive in livewells need to understand that these fish not only have to be given good conditions to survive confinement, but they also have to recover from the stress of capture — primarily the oxygen debt that results from playing the fish until it can be landed.

Numerous studies have documented that the mortality of tournament-caught bass goes up in the summer. Although increased mortality is a common outcome of summer tournaments, it doesn’t have to be. There are simple things anglers and tournament organizers can do to keep survival high.

Modern bass boats have adequate livewell systems for keeping bass alive in any season. In cooler seasons — when the water temperature is below 75 degrees — just turn on the aerator pumps and let them run. Switch to recirculate mode when the boat is on plane. Run the aerator pumps continuously if you have more than 5 pounds of bass in the ’well.

No, it won’t drain your cranking battery. If it does, you needed a new one anyway.

When the water warms above 75 degrees, there are three simple things anglers need to do to keep their catch alive:

Step one — Control temperature

Fill the livewell first thing in the morning when the water is cool, switch to recirculate mode and add ice.

In a study of 12 summertime bass tournaments throughout Mississippi, 7 percent of the bass weighed in by experienced tournament anglers who used their conventional livewell-management procedures were judged dead at weigh in. Only 3.5 percent of the bass weighed in by anglers in the same tournaments who volunteered to use ice and follow the above livewell temperature recommendations were judged dead at weigh in.

Furthermore, the bass from the temperature-controlled livewells had a heavy slime coat, but the bass from the warm livewells felt dry and rough. The weighmaster could tell which anglers used ice because their fish were more active and harder to weigh.

The best way to cool the livewell water is to add frozen half-gallon, water-filled plastic bottles like a milk jug. The block of ice melts slowly and will keep the water temperature stable for a couple hours.

Ten to 12 jugs are enough to control livewell temperature throughout a tournament day during the hottest conditions you will face in Mississippi if your livewell is insulated. Add a fresh jug of ice as needed, and do not cool the water below the suggested temperature.

Is there chlorine in the ice? Maybe, but it won’t mix with the livewell water if you leave the cap on the jug.

The cooler in your top-end bass boat won’t hold 12 half-gallon milk jugs? Mine won’t either. Empty one of your aft dry storage compartments and use it as a cooler. You’ll have plenty of ice to keep your bass healthy, and you can carry extra cold drinks to keep you happy. And, hey, how much tackle do you need in the summer: A Carolina rig, a jig and a few deep-diving crankbaits gets it done.

Step two — Provide plenty of oxygen

Recent research indicates that walleye held in livewells for eight hours at 2 parts per million dissolved oxygen die within 24 hours. An important note: All fish survived the eight hours livewell confinement, but all died within 24 hours after weigh-in; the fact that your fish are alive at weigh in does not mean they are alive one day or one week later.

OK, this research was for walleye. Maybe walleye need a little more oxygen than bass, but until this research is repeated for bass, it’s a safe assumption that bass, too, need more than 2 ppm dissolved oxygen to survive. Continuously high levels of oxygen are needed to keep the bass alive and to help them recover from the stress of capture.

There are several add-on aeration devices on the market, but pumped-water aeration systems that are standard equipment in modern bass boats are adequate for catches up to 20 pounds if you run the aerators (recirculation pumps) continuously and you cool the water.

It is not possible to over-aerate livewell water with a pumped-water aeration system. The levels of super-saturation of dissolved oxygen that may be achieved by constant aeration are not harmful.

Cooling the water provides comfortable conditions for the bass, but it also helps provide adequate oxygen. Cooler water holds more oxygen, so your aeration system is more efficient. Plus, bass in cooler water need and consume less oxygen.

Bottom line: Cooling the water and continuous operation of the recirculation pumps is the best way to provide sufficient oxygen.

Step three — Provide fresh water every three hours

Bass excrete ammonia. If you have more than 5 pounds of bass in the livewell, ammonia can increase to toxic levels before weigh-in.

To avoid toxic ammonia, give the fish fresh water. Pump out and refill or flush the livewell, turn the livewell back to recirculate mode and add ice to bring the temperature to the desired range.

Good fish handling, better fishing

Most bass anglers will agree that catch and release means more and bigger bass to catch in the future. But catch and release only works if the bass survives to grow, reproduce and, hopefully, be caught again.

Regardless of the season, conservation-minded anglers should land fish quickly, protect the bass’ slime coat by handling the fish with wet hands and not letting them flop on the carpet, hold bass vertically while quickly removing hooks and minimize exposure to air.

Summer tournaments pose fish care challenges, but they can be easily met. The three, simple steps described above don’t cost anything and take less than five minutes out of a fishing day.

That’s a pretty small investment for better bass fishing.

Target livewell temperatures

These are target temperatures for livewell water for these morning surface water temperatures:

• 75-80 degrees surface temp — 75 degrees in livewell

• 81-85 degrees surface temp — 78 degrees in livewell

Greater than 85 degrees surface temp— 80 degrees in livewell