Fall will soon be here and the changes are magnificent. Cooler temperatures and shorter days make for pleasant weather and plenty of beautiful colors. Here are reasons for this changing season:

COOLER WEATHER: Have you ever noticed that fall tends to feel warmer than spring? This is because the spring weather is warming the ground and fall temperatures are cooling the ground. Cooler fall temperatures don’t occur by accident. The days grow shorter and the earth’s axis tilts, creating cooler temperatures by the sun’s angle on the earth, dispelling the old theory that the earth moved farther from the sun during autumn, not the case.

CHANGING LEAVES: After a summer’s worth of creating energy, the photosynthesis machine slowly comes to a halt. Photosynthesis is the process of plants creating energy. Chlorophyll gives leaves their green color, and help photosynthesis occur along with sunlight.

When days grow shorter, the rate of photosynthesis decreases and the chlorophyll goes away. Longer nights in early fall allow cells near the juncture of the leaf and stem to divide rapidly but not expand. This action of the cells forms the abscission layer. The abscission layer blocks transportation of materials from the leaf to the branch and from the roots to leaves and why most professionals prune tree limbs after this process has occurred.  

What remains are colors that were always present, yellows or oranges, but was covered by chlorophyll. Cool nights make glucose trapped in leaves turn reddish, like in sugar maples.

BUTTERFLY MIGRATIONS: Monarchs are the main migrating butterfly group. Missouri Department of Conservation sources claim that more than 200 million monarchs, each weighing 1/50 of an ounce, fly some 4,000 miles to and from selected wintering grounds in the mountains of central Mexico. The trip starts in Canada.

Results of this migration tradition that started in the last ice age have increased butterfly numbers throughout time. Migrations in this area normally peak around Oct. 1.

I walked into a major migration of monarchs on our family farm several years ago. I was squirrel hunting on a bright fall day when warm sunlight made me forget that winter was approaching. I will never forget that remarkable scene at the edge of a big timbered strip.

I watched in amazement as a blizzard of flashing orange and black wings from thousands of monarchs filled the air. My presence must have startled some who lifted in the air. Their flight evidently signaled the entire group to lift off their comfortable perches.

I quickly sat on a log. My lack of movement calmed down the group who landed, filling limbs and bushes. Small groups seemed to stay together. I stood up and was rewarded by thousands of butterflies flittering all around me. I decided to forget about hunting and sat down to observe.

Occasionally a group of monarchs would drive away an unwanted visitor. Other insects like a fly would meet intense reactions. Clouds of butterflies fluttered around the intruder until it gladly departed. I spent two hours watching this remarkable vision. I returned two days later to sadly find this remarkable squadron of beauty had moved on.

FISH REACTION TO FALL: Fish behavior is responsive to water temperature because they are cold-blooded. The best places to fish as fall progresses may be shallow waters along south facing shorelines where they warm the fastest, a great walleye tip.

Air temperatures change lake temperatures, especially in surface layers that are warm during the day and cool at night. This triggers fish to gorge for winter. The water that is too cold for you to swim in feels great to the fish, increasing their energy levels.

Fall is a great time to fish aggressive lures. Briskly walking the dog with a Zara Spook or running buzz baits over submerged cover is effective. Plastic worms are still good and floating balsa or plastic minnow imitations are effective, too.

LAKE TURNOVERS: Fall changes can be drastic on a lake. First, lake turnovers will stop the fish from feeders for a short period. But exactly what is this turnover?

Lake turnover is the process of a lake's water turning over from top to bottom. During summer, the surface layer is the warmest. It is heated by the sun. The deepest layer is the coldest. The sun's radiation does not reach this cold, dark layer.

During the fall, warm surface water begins to cool. As water cools, it becomes denser, causing it to sink. This dense water forces the water to rise, "turning over" the layers. Sound confusing? I agree.

Turnovers change fish habits too. Gamefish are concentrated more tightly during the turnover period than at any other time of the year. In summer, you'll find fish scattered over our large flats, cruising weed lines or even chasing baitfish in open water. But in fall, clumps of fish hold in very distinct locations.

Most fish favor sharp-breaking structure, so even if they're resting in deep water and feeding in much shallower water, they're not moving far. And often you'll find many different kinds of fish concentrated in the same area. Once the fish "set up" in their late-fall locations, they're likely to stay there until freeze-up.

The great J.A. Robinson taught me how to catch fall crappie on Waukomis before the days of depth finders, middle 1960’s. We anchored over crappie beds, dropped minnows and did a reel turn every minute. We kept track of the turns and then dropped back and reel up to the productive region.

Crappie were suspended on a line, no higher or lower, just a certain depth. We easily caught our limits until freeze. That meant plenty of fillet dinners at the Robinsons’ or my mom’s home.

Fall is almost here. Stock your firewood and enjoy the beautiful changing of this season.

– Kenneth Kieser, a veteran outdoors writer and member of the Waterfowlers Hall of Fame and National Fresh Water Fishing Hall of Fame, writes a weekly outdoors column for The Examiner. Reach him at kieserkenneth@gmail.com.