Find the thermocline on your favorite Mississippi crappie lake and open up some great, hot-weather fishing opportunities.
Over a 40-year career of chasing fish, game and stories about the catching and killing thereof, I can clearly recall the dumbest thing I have ever considered doing in the pursuit of such journalism.
It was August, just before the turn of the century, in 1999.
Remember Y2K?
Rabbit Rogers, only the best crappie fisherman I have ever known, called me one afternoon and said simply: “They’re biting!”
That meant an invitation for a long-awaited summertime crappie trip with Rogers on Barnett Reservoir was being offered. I was sitting at my desk at the newspaper, enjoying the air conditioning, worried about what I could possibly find to write about in the middle of a heat wave. It was torrid.
Without thinking sanely, I immediately seized the opportunity.
“When we going?” was my response.
All I heard was laughter through the phone, which should have been a clue.
“Well, they’re calling for a high of 102 tomorrow, so we need to go,” Rabbit said. “The hotter the temperature, the hotter the bite. Are you ready for this?”
A writer without a story, facing a deadline, will do stupid things. I did.
“What time and what ramp?” I asked. “Sunrise is at 5:45.”
Another clue followed — more laughter
“Well, there’s no use getting there at daylight,” he said. “They don’t bite real good until the sun is high and the temperature is darn near unbearable. That’s when we need to be on ’em. No need to wear ourselves out in the morning. Let’s meet at Highway 43 at 10. Wear something white and light and a big hat. Bring water. You best leave your beer at the house.”
Oh, Lord!
Here’s the short version of the trip. We went. It was hot. We limited out — 60 fish between us — in two hours. We fished for four more hours and threw back way more crappie than we kept.
To this very day, it was the best crappie-fishing trip I’ve ever had, and probably the one of which I should be the most proud — not because of how many we caught, but because I survived.
Know this: the amount of sunscreen I wore that day weighed more than my pants and shirt. Between us, we drank a case of bottled water and ate a couple of Rogers’ peanut butter and banana sandwiches.
It was fine.
All About The Sun
Rogers taught me a lot about crappie fishing that day, and he helped me learn an important lesson about the water and the phenomenon known as the thermocline. I knew what it was before then, but I never understood how it impacted fishing.
“That’s the key to catching crappie in the summer, especially on a lake like Barnett Reservoir,” Rogers said. “Once the thermocline is established, every fish in the lake will be forced to live in a small layer of water just above the thermocline. Nature helps fishermen by creating that.”
The definition: A thermocline — aka the thermal layer or the metalimnion in lakes — is a thin but distinct layer in a large body of fluid (e.g. water, as in an ocean or lake) in which temperature changes more rapidly with depth than it do in the layers above or below.
So one would think that the fish, stressed from the heat, would be as deep as they could get to avoid the high temperatures, surface temperatures above 90 degrees.
“The thing about a thermocline that impacts fish is that the level of dissolved oxygen below the thermocline in the cooler water is too low to support fish,” explained Ron Garavelli, the former director of fisheries for the Mississippi Department of Wildlife, Fisheries and Parks. “Fish, like crappie, simply can’t survive that deep, but they also can’t survive in hot waters near the surface, which is the water with the highest level of dissolved oxygen.
“Crappie will try to find that layer of water that provides the coolest temperatures with enough oxygen to sustain them. That is usually about a foot or two of water just above the thermocline.”
Garavelli also said that the thermocline can change, not only day to day but hour to hour. On Barnett, it takes a horribly hot day for it to establish itself so firmly that a fisherman can actually find it on his or her fish-finding electronics by turning up the gain to increase the unit’s sensibility.
Rogers had an easier way to find it.
“I drop a jig down in one of my honey holes, and when a fish hits it, I know I’ve found the right depth,” he said. “Works every time.”
That day in August 1999, it was between 11 and 12 feet. Not a single fish we caught — and we caught over 150 — was taken at a shallower or deeper depth.
“It Ain’t What, It’s Where”
“Once you’ve established the magic depth, you’re halfway there,” Rogers said. “The other part of the equation is finding the kind of cover or structure the fish like. On Barnett, that’s old timber or brush piles. But on some of the state’s other great crappie lakes, like Grenada, Enid and Sardis, most of the timber is gone, so the fish relate more to changes in depth, like channels and ledges. You have to learn the contour changes on those.”
On Barnett, literally thousands of trees, stumps and brush piles are still available, but only a tiny fraction of them will attract and hold fish.
“If a piece of cover doesn’t provide some horizontal (flat) cover, forget it,” Rogers said. “A fish can’t shut its eyes. It depends on putting something between its head and the sun. Finding something horizontal, like an old limb or a mass of timber like a brush pile, is gold.”
A vertical tree, devoid of sun, can provide protection, but only on one side of the timber, and as the sun traverses the sky, the shade moves.
Horizontal cover offers constant shade.
“Take an old lake bed in Barnett like Saddlebag or Three Prong,” Rogers said. “There’s hundreds of trees in each area, but only about a handful offer a good horizontal limb or limbs. Those are the trees and the limbs to find and concentrate on.”
Once you’ve established the depth by finding the thermocline and identified the trees with limbs closest to that depth, you’re on your way to a limit of slab crappie for a summertime fish fry. Don’t worry so much about jig color or type.
“Like I’ve always said, it ain’t what, but where,” Rogers said.
Over decades of fishing, Rogers has established a lot of hot spots in the 33,000-acre lake by building and placing crappie structure. All of them offer an abundance of horizontal cover, and all of them produce outstanding summer fishing, on a given day.
Trolling Another Option
Back in that time period, very few crappie fishermen trolled at Barnett. It was a practice used effectively at Grenada, Sardis and Enid, where anglers needed a way to cover a lot of water quickly.
“The timber up here is long gone,” said guide John Harrison. “We depend on contour changes in the summer, any area with a drop or a sudden change in depth. It can be a long lake point, a creek or river channel, anywhere there’s a depth change.”
Trollers there have three methods of catching fish: pushing, pulling or power-trolling.
Pushing is the standard method of lining up rods across the boat’s bow, each with one or two jigs — with or without a minnow — and using the trolling motor to push the baits into schools of crappie.
Pulling usually involves an array of rods off the boat’s stern, each with a deep- or medium-diving crankbait. Fishermen, often in a pontoon boat, can pull four or five or even six rods — depending on what the law allows — using the gas motor at idle speed.
Power-trolling is what most fishermen call a method of pushing that involves extremely heavy sinkers, 2 or more ounces, and two jigs. It requires stout jigging poles and a three-way swivel. The terminal line from the reel is tied to the top swivel, and a jighead is attached with about 18 inches or more of fluorocarbon leader to one of the other swivels. Off the third is another piece of fluorocarbon line that contains the heavy sinker with a second jig about a foot or two below the sinker.
Harrison prefers power-trolling and pushes about 1.2 miles per hour using his trolling motor. It allows him to cover a lot of water and a lot of different depths.
“They can vary from 7 or 8 feet down to 11 or 12 feet, even deeper, depending on the temperature or thermocline,” he said.
Since Y2K, trolling has expanded south to Barnett and west to the Mississippi River oxbow lakes.
On Barnett, veteran angler Paul Johnson is working on perfecting the crankbait pull on the lake.
“I figured it had to work here, if it works there,” he said. “Used to be you never saw crappie fishermen on the open waters of the lower main lake in the summer. They’d be there in the spring during the spawn, fishing the rocks and the shallow flats, but once the summer came, they all went to the upper end of the old lake beds and standing timber.
“It only made sense that the fish that spawn on the dam or other areas on the lower lake live near there in the summer. It wasn’t like the crappie swam all the way down the lake to the dam to spawn, and then swam all the way back. A lot of us starting looking at pulling crankbaits.”
Now, a lot of crappie fishermen have already taken up the spider rigs and are slowly pushing an array of jigs through Barnett, especially on the upper end of the lake.
But down on the lower end, where the water is more exposed to the elements like wind, it is more difficult. Trolling with crankbaits and big engine was a lot easier.
“We simply found the contour changes with maps and electronics and began pulling crankbaits, and you know what, it does work on Barnett,” Johnson said. “Now, you see scores of fishermen doing that here, and it still works.”
Over the past decade, several lure companies have begun catering to crappie fishermen, designing and building crankbaits just for crappie — smaller-bodied lures that dive to different depths.
All of that combined have made crappie a year-round fish, and some of the hottest action comes at the hottest time of the year: summer.
Grab the water, the sunscreen and big hats, where light clothing and don’t be afraid to test your limits in the heat.
“You’ll be surprised at how hot the action can be,” Rogers said. “Pleasantly surprised.”