by M. L. Anderson
You’ve pre-fished for a couple of weeks, and you’ve got a killer spot in a big cove. You’ve even got a great boat number and you’re one of the first ones out, but when you reach your best area, it stinks like rotten eggs and the water looks like the sewer backed up in it. What’s going on? Welcome to the fall turnover, when all the decaying vegetation on the bottom of the lake rises to the top. Hence the smell and the nasty looking water.
What It Is
In the summer, the surface layer of the water is the warmest because it is heated by the sun. The deepest layer is the coldest because the sun’s heat doesn’t reach this far. When fall arrives and air temperatures begin to dip, the surface water starts to cool off. Colder water is denser, so the cooling water starts to sink, eventually forcing the deep layer to rise, “turning over” the water.
Wait a minute! If colder water is denser, why doesn’t ice form at the bottom of the lake instead of the top? That’s because water reaches maximum density at 39 degrees Fahrenheit. This is unique to water, and it means that ice is less dense than liquid water, so it floats. Anything above or below 39 degrees is less dense.
That deep water has a lot of decaying matter and sulfurous gases, so when it reaches the surface, it’s easy to tell that the turnover has begun. To know for sure, just drop a thermometer. If the whole water column is the same temperature, you’ll can be certain that the water has turned over. If your depthfinder is showing baitfish all over the place, that’s another big clue.
In the spring, when ice melt starts to run into the lakes, the same thing can happen, but spring turnover is usually a lot less intense. Some lakes, like Roosevelt Lake in Arizona, only have turnover once a year, in the fall.
How to Respond
For starters, large lakes do not all turn over at the same time. In a study at Roosevelt Lake in 2002, they discovered that the lake begins to turn over starting in September, and the Tonto end turns over the soonest because it is the shallowest part of the lake. The turnover process usually progresses from shallow to deeper areas. So, if your area stinks (literally), just relocate -- find a deeper cove or head to the main lake. Take heart – despite what you may have heard, the turnover doesn’t make fishing terrible for weeks on end. It’s usually a fairly short process and if you only go to a lake every couple of weeks or so, it may have happened and you never even noticed.
If the entire lake is in the middle of turnover, try using a crankbait or spinnerbait and go after bass that are cruising around looking for those baitfish that are all over the place. If the turnover has just ended, the shallow fish will be the ones who are the most acclimated to the cooler water, so fishing shallow may be your best bet.
The actual turnover may be brief, but the transition from summer to fall can be tough regardless. Rob VanderKooi is a western tournament angler who is also a guide, and he knows how difficult it can be to pattern bass in the fall. “The fish may be twenty-five feet deep on points just about all summer, then all of a sudden fall happens, and those fish are gone,” he says. They could literally be anywhere, and Rob says that the bait fish scatter this time of year, and the bass naturally follow them. The weather that we are experiencing can still feel like summer, but fish are in another world, and things are different there. So what’s a guy to do?
Rob’s best big-fish baits for fall are buzzbaits and big plastics like Yamamoto Kreatures and Flappin Hogs. You can throw a buzzbait all over the lake, he says, and flipping a big Kreature or a Flappin Hog into brush and cover is his go-to technique for big fish this time of year. Since the baitfish are so scattered, you can watch your graph for suspended balls of shad, and you can watch for boils and throw topwater lures or spoons at those.
Fall is when a versatile fisherman shines, and proficiency in a variety of techniques is crucial for catching bass that are scattered at all different depths and different types of structure. Gary Dobyns says that in early September it’s still summer but by the first of October it’s almost winter – there’s a big swing during those two months. The shad and pond smelt are hanging out in big balls and topwater is good all day, but especially in the morning. The fish push the shad up and if you find a school, you can have a lot of fun, especially with spotted bass.
There are also plenty of suspended fish working shad in the middle of the lake. It doesn’t matter how deep it is out there, so drop shots and Yamamoto Fat Baby Craws or Psycho Dads are a good bet, too. The cooler water makes the bass more aggressive, so reaction baits in shad colors (or whatever they eat on your lake) will often work as well. Dobyns usually starts in the main lake this time of year. In the main body they often suspend around trees and standing timber on points, humps, and submerged islands. Structure is key in the fall, he says, and his number one choice is humps and reefs, with cuts and channels being second. He’ll almost always start on a reef or island this time of year.
Spotted bass form huge schools curing this this time and you can catch a lot of them – if they get spooked, just back off for a bit. Use dart heads, jigs, and 1-tonners with Hula Grubs. This is the time of year that you can do pretty much whatever you like – Gary uses a lot of topwater like Spooks, Sammys, and Lucky Craft poppers, with a Spook being his first choice for windy days. If there isn’t much wind, he throws the Sammy. Buzzbaits are great when the bass are thrashing around on top and so are crankbaits.
Swimming a big Yamamoto single-tail grub on a dart head is a fantastic way to catch a lot of fish this time of year – you can swim it at any depth you like, and the fish just inhale it. Use it on rocky banks with the hook exposed, let it sink down, then swim it back slow and steady. It’s also good for when you see the fish boiling – throw it past the boil on spinning gear and swim it back.
As you can see, fall is a smorgasbord – you have to be willing to try a variety of techniques, lures, and locations, but once you find what’s working you can often load the boat. If the water looks and smells bad where you are, just fire up the big motor and move. You may have to re-group and try something completely different, but if you keep at it you’re almost sure to find them. Turnover isn’t the end of the world – it doesn’t last long and it doesn’t happen everywhere at once, so don’t let it mess with your head.