Wind This!

October 05, 2007

Wind This!
by P. Cody Fiduccia

I first learned about wind, thermals, and convection currents from one of the nation’s leading whitetail authorities, Peter Fiduccia – who just happens to be my Dad. He has preached to me about how unpredictable all types of wind currents can be and how they can negatively or positively affect a day of deer hunting since I was old enough to listen and understand what he was saying. Over the years, I have applied what he taught me and some new tactics of my own to take my deer hunting to the next level.

I was posted in a tree stand on our farm that was productive only when the wind was out of the west. It was a little after four in the afternoon when a buck came from the swamp and made his way to me. A constant breeze blew from the buck to me. All of a sudden, 40 yards out, the buck stopped, lifted his nose and without hesitation he disappeared.

Surprised, I wondered what caused the buck to run? I knew the prevailing wind was blowing in my favor. I hadn’t crossed his trail, so he couldn’t have picked up my odor, and I took a shower with In-Scents soap and put on my clothes that had been treated with Dead Buck Walking products before just an hour before the hunt, so I was reasonably sure I had kept my body and clothing odor to an absolute minimum if not totally scent free.

I decided to spray some powder from my wind detector that I always carry in my backpack. When I sprayed the powder in the air, what I saw would change what I thought about wind currents forever. At first, I watched as the white powder confirmed that my scent was drifting away from the buck. Then about 15 yards behind my stand, the powder dropped suddenly and quickly blew back past me toward the buck. I was astonished that a low wind current could move in the opposite direction of the prevailing winds and was strong enough to even spook a buck.

What I learned from my the Deer Doctor (my Dad), from reading and talking about wind and air currents with certified biologists like Jay McAninch, the President and CEO of the Archery Trade Association (ATA), was as profound as it was enlightening and helpful. The information below will help you not only understand wind currents better, it will help you see and bag more deer this season.

Prevailing Winds
In every area you hunt there will be a prevailing wind direction during the hunting season. It is the predictable breeze that we are all told to keep in our faces in order to prevent deer from scenting hunters on stand, still-hunting or making a drive. Over most of North America, the prevailing wind is from the North, West, or Northwest. This wind can often be the strongest of all the winds that blow during deer season. Other times, it is nothing more than a continuous light breeze. It has been documented that even though deer will move in all directions in relation to the wind, they prefer to move into the wind whenever they can. Seasoned hunters know that deer trails match the prevailing wind direction and customary wind changes. Knowing the prevailing winds is especially important in more open habitats. Choosing which side of a bottle neck or funnel will be determined by the prevailing winds. When posting along the edges of agricultural fields, pay attention to the prevailing wind because most times the does and fawns enter first. If they don’t pick up your scent, this will be crucial to having a buck come into the field as well.

Deflective/Convection Currents
Deflective wind currents are the product of prevailing wind flowing over an obstruction or flowing into an obstacle that changes the direction of the airflow. For instance, if your stand is in front of a thick group of tall pines or a steep rise or depression, these obstructions can disrupt the flow of a prevailing breeze. For hunters, wind current that is deflected downward is trouble because, if the velocity is strong enough, that current can create a back draft much like the undertow on ocean beaches. If you are in a tree stand, you might never know that the wind current deflected after it passed you and actually flowed back “under” the prevailing stream.
Deflective currents result in many “micro” wind currents that become isolated and localized over relatively small areas. Imagine how water directly hitting a surface splashes in all directions until its initial velocity is lost–and that is what happens when wind hits an obstacle. These small pockets of air are called convection cells and are capable of going in any direction–which spells trouble for the unaware hunter. Deflective currents are more prevalent under low pressure centers which are common as the days cool and cold fronts start pushing south from Canada. Beginning in October, deflective wind currents are predominant air movements and that means deer hunters should not only know these flows exist but also how they work. When hunting from the ground or from a tree stand, you should take into account the terrain or structure that lies behind the stand. Consider how the prevailing wind will be deflected in the vicinity of your stand. Be sure to test the currents using a fine spray powder from each stand and record your findings in a daily log book. After noting the wind flows, position each stand to maximize your ability to predict what the air currents will be doing. If the airflow in an area seems unpredictable, then you must move completely from the area. Remember, deflective currents don’t occur all the time and vary in speed. After sitting in a stand several times, you will begin to learn how to use a convection cell or deflective wind flow to your advantage. “The hunters I’ve known who consistently take mature bucks are guys whose stand placement strategy is dictated first by the direction of the prevailing winds and, second, by the air flows in and around each stand. Knowing how deer will be receiving wind borne scents is the key to successful hunting,” said Jay McAninch, CEO/President of the Archery Trade Association.

Thermal Currents
Thermal winds are airflows that occur as the air temperature increases in the morning (hot air rises and cool air falls). All hunters are affected by thermal winds which result from temperature differentials between the ground or water bodies and the air close to the earth. Thermal activity is usually highest during the first and last hours of daylight and last until the circulating air and the ground and water are similar in temperature. This means thermals are most active during the prime times that deer hunters are on stand. At sunrise, the ground and water are still cool from the nighttime temperatures. So, as the sun warms the air, there will be a rising wind current. You will have an advantage if you sit on the high side of a stand on a slope and if you approach your stand from a ridge top; your scent will drift up. Used to your advantage, early morning thermals can contribute to a couple of hours of action-packed hunting. In the evening, the opposite effect takes place. The air cools quickly as the sun sets while the ground and water bodies remain warm for several hours. In this situation, a down draft will occur as the cool air sinks (we’ve all felt that sudden quick chill as we pass by an area that is lower than the higher ground we came from). During this time you should enter your stand from the valley bottoms and not the ridge tops and it pays to take a stand below a hillside trail. Within a short time you will begin to notice that the deer will pass your stand undisturbed because your scent is not being carried to them. According to McAninch, “Hunting from stands in forest areas where there is water and hilly terrain is ideal for taking advantage of morning and evening thermals. Once deer travel patterns are known, the experienced hunter can move in and out of the area and can hunt in positions where deer are at a serious disadvantage. In addition, using thermals can mean the movements of other hunters can be used to your advantage.”

The Bottom Line
Hunters who ignore wind directions and currents often see fewer deer. And, the deer they do see are nervous and quick to spook. The seasoned hunter always keeps wind uppermost in his mind. To consistently see more deer consider the prevailing winds, deflective winds, and thermals and how they will affect your hunt each time you go afield. If you become wind savvy, you will immediately improve your deer hunting success–ten-fold. You will see far many more whitetails standing calmly within range which will be the key to bagging your next trophy buck!

Woods N Water | PO Box 10 South New Berlin, NY 13843 | 607-548-4011