The following is from Gene Wensel's new book "Buckskin and Bone - Postgraduate Whitetails"
If I had to name the single most common deficit among bowhunters who repeatedly
fall short of their potential, it would have to be negligence, or ignorance, of
the many ways wind can either help or hinder hunting situations. I remember a
farmer asking us why we entered the patch of woods behind his house from
different directions on various days. When we told him it depended on the wind,
he pondered a few seconds before asking, “What’s the wind have to do with it?”
Now, that is a classic quote!
Why this subject of wind seems to go in and out of so many ears is probably
because it can be boring. It’s also very hard to explain things we can’t
necessarily see. Wind currents are not exactly photogenic. Yes, we can
feel air movement and we are often able to see results or activity, but
some of the most subtle pitfalls of comprehension leave us with too many
mysteries and unanswered questions. Even taking into consideration various
obstacles, pitch of the terrain, trees with leaves vs. no foliage, air
temperatures and whatnot, all air movement will differ according to even simple
factors such as velocity. I categorize air movement into three classes: light air
movement like thermals, with speeds under 3 mph; the medium movement of breezes
3-20 mph, and the effects of higher wind speeds over 20 mph. The important
thing is that air reacts differently at increased velocities.
Before I go any further into the subject of wind and odors, I probably should
state that I am NOT a scent control freak. I don’t wear carbon suits. I don’t
spray myself down with various misted potions, nor do I chew special gum. I
don’t quit eating red meat before hunting season. I don’t shower with magic
formula soaps every morning before I go hunting; unscented brands will do.
Although I change underwear and socks every day, I don’t launder my hunting
clothing on a daily basis, nor do I carry them around in tubs filled with fresh
dirt or forest debris. I chew leaf tobacco and pee right out of my stands. But,
I do pay attention to the wind at all times when I’m in the
woods. I have trained myself to be constantly aware of it, as well as how it
reacts to various structural deviations and various velocities. My puff bottle
is always handy. I use unscented tooth paste, soaps and deodorant. I shower
every evening, not right before I go out into cold weather. I always wear
rubber boots to minimize ground odor. I guess what I’m trying to say is that
I’m very aware of odors but not a freak about it. I tend to avoid most
commercial crutches. I’m lots more interested in paying attention to the wind.
I believe no matter what species, no matter how sensitive a nose we’re dealing
with, game animals are physically unable to smell any free
floating scent or odor upwind of its source without a back draft or residual
attachment.
Since human beings are not blessed with acute olfaction at birth, hunters must train themselves to constantly be attentive to wind direction and air movement. Aside
from understanding exactly how breezes and thermals react with structure, the
first and most important part of wind training has to do with being habitually
alert to whatever direction the slightest breezes are drifting. I don’t
remember ever reading anything from any outdoor writer about the necessity of
“training” for this awareness, but training is exactly what we all should have
done during our “hunting apprenticeship” years. Sadly, many modern hunters seem
to skip or fast forward through their apprenticeship years. Many people just
say, “Ya, ya….I pay attention to the wind.” For some reason, many hunters hear
but don’t listen. Many don’t carry any sort of wind detection tools, or they
neglect to use them often enough with slight breezes when they are needed most.
Wetting a finger just doesn’t get it! We must train ourselves to be conscious
of even minimal breezes any time we are outdoors. Since it’s a repetitive
training process, almost everyone will eventually get much better at it. The
sad part is you’ll never really know when you get there; but trust me,
awareness is worth the time and effort.
Whitetail deer know they are a prey species. I’m also convinced visual and auditory predators such as felines and raptors know which species are prey.
On the other hand, olfactory predators like canines or snakes put most
of their trust in their noses. Humans are essentially visual predators;
whitetails are olfactory, auditory and visual prey, usually in that order. As
far as physical facilities, olfactory and auditory skills usually favor prey
species rather than predators, an important fact to remember. How a prey
species uses its nose to perceive scents and various odor mixtures is a study
all by itself; the same can be said for predators. Prey species always rely on
their noses to choose bedding areas, to pick hiding places or decide on
security cover.
Daily weather forecasts are very valuable to hunters. If you don’t have access
to the internet or television, a weather radio is your best option. I want to
know the forecast as well as the predicted wind direction and velocity. With
that said, in all honesty, I don’t pay much attention to forecasts past two
days. Nor do I pay much attention to a rising or falling barometer to predict
game movement because I’m going out regardless. I feel pretty much the same
about moon charts and solunar tables; I’m going out anyway. I don’t want to
start my hunting day with a negative attitude because a chart told me today
won’t have good game activity. I mostly want to consider stand options, hunting
strategies and know what to wear.
Okay, big words like perception, apprehension, recognition, comprehension and
appreciation have been laid on the table. Now let’s talk about how to use wind
to our best advantage as hunting predators. The influence of outdoor air flow
is a challenge that can present entirely different results, far above and
beyond simple cat and mouse scenarios.
Always think of wind as invisible water without the effects of gravity.
As it flows at various speeds, it will pretty much carry your scent
“downstream.” Picture in your mind what happens when invisible water hits
various objects in its path. It might divert at angles, increase speed, or
swirl into slower pools or eddies. An obstruction will never permanently stop
it, only alter velocity or direction.
Moving air often acts differently in the exact same spots seasonally. As an
example, air moving across an open field will react differently when it hits
heavy foliage on trees than it does after all the leaves have shed. Results
also depend on the size and shape of various species of leaves or trees. It
will also act differently with and without a canopy of trees overhead as well
as the density of understory.
Air movement is a study itself, but for hunting purposes, there are basic rules
to learn and remember. Warm air rises, cool air falls. When cool morning air is
hit by sunshine, it quickly warms to rise as thermals. When black dirt absorbs
sunlight, the resultant warmth causes rising thermals. This means
thermalization will occur quicker when sunlight hits a newly plowed dirt field
than it will when it hits a grassy meadow. Warming and/or cooling of air takes
place almost every day of the year.
Perfectly calm outdoor air is really
quite rare, at least for any length of time. Scent seldom pools for long
periods. Almost any given area will have one prevailing wind
direction but two predominant wind directions. The
predominant winds for an area might be out of either the northwest or southwest
but the prevailing wind for that same area today could be out of the southeast.
Vegetation often gives clues to predominant wind direction. In open areas,
notice which way trees lean. Also note which way tall weeds or long grass in
vast open areas grows. Winds often change with the seasons in many given
regions. Ask a local farmer or skilled woodsman, check with a regional
weatherman, a pilot, or any small airport. Northwest and/or southwest winds are
probably the most common on a national basis but many areas such as southern or
coastal regions have lots of southeast winds. I hang most of my stands
according to predominant wind directions but hunt each according to prevailing
wind direction. Make it a point to always have a few stands set up for odd
winds. Easterly winds, uncommon but not rare in my hunting areas, require
enough foresight to allow back up options on days with unusual wind directions.
We make it a habit to not only name or number our stands, 
but also record the
best wind directions to hunt each. We also label each as best for morning,
evening, all day, or “anytime” hunts.
I want to address the subject of wind and the deer themselves. I will even go
so far as to say some deer understand perfectly things like updrafts and eddies
and even use them to disperse their scent from directions predators might
approach. This is exactly what causes certain deer to hold tight at close range
while others run first and hide later. A lot of these reactions to disturbance
depend on age, sex and personality of each deer. What most whitetails don’t
seem to grasp is the fact that man the predator cannot smell worth a hoot. Most
deer visually soon learn that humans can’t see very well in low light
but they still assume we can smell as well as they can.
Wind velocity is an important factor. Most game animals don’t like wind
velocities over about 20 mph. High winds often put game down to where they hold
tight until it subsides. The main reasons they don’t like windy conditions are
because they can’t smell as well, can’t hear as well, and can’t see movement as
well while all foliage is moving. They can’t trust high winds enough to pin
point trouble, yet they can’t do much about it except to lay low until higher
winds subside. If we were able to ask whitetails what sort of wind velocity
they prefer, I’m sure the answer would be steady, damp breezes, faster than
thermals but under 10 mph. Along the same lines, many bucks don’t like calm
air. They will often move very slowly and even stop or stand in one spot until
they feel a slight wind that allows them to move forward. My brother labels
these deer “slow walkers.” They are most often mature bucks.
Most game animals realize scent lingers longer in damp air. Deer use and rely
upon their noses for directional information. Of course all deer pay attention
to whatever scents a breeze brings, but they also learn to tell direction of
travel from what is retained on the ground. Many humans fail to realize the
almost incomprehensible powers of excellent noses in many species. Think about
this; when a beagle hits a rabbit track, even on bare ground, the dog very
seldom follows the trail the wrong direction. What that tells us is the dog can
almost immediately tell the tracks a couple feet to the left (or right) are
fresher than the ones they just had their nose in. Very impressive!
Deer not only use their noses for defensive purposes, but to “communicate”
among themselves through olfactory powers. Above and beyond defensive measures,
scent left on rubs, in scrapes, on licking branches, along trails, and even on
themselves, all relay useful information to whitetails. With all that being said,
here comes the kicker…. All deer pay attention to wind but not all of them
ever learn how to use it! Once again, it seems to be a timely training
process that some whitetails don’t ever master. I see many deer moving up wind,
downwind, or cross wind all the time. You do too.
Almost all mature deer have learned to use moving air to their advantage. In
fact, in my opinion, one of the main reasons they live long enough to become
mature deer in the first place is the fact they have learned to utilize wind
currents to the best of their abilities and advantages.
Mature deer, both bucks and does, realize, and eventually learn there are
certain terrain structures that make air more stable. For instance, air on
slopes is more stable than that at the bottom of a draw or on top of a ridge.
Or, game movement patterns will always be better on the prevailing upwind side
of any large body of water.
Lone deer will almost always bed with the wind at their backs, using their eyes
to protect their front. More than a couple deer bedded together will lay facing
in multiple directions on purpose to protect themselves visually even
better. Bucks bedding together in bachelor groups usually face in opposite
directions because looking at each other could be interpreted as aggression.
You can easily prove directional bedding to yourself by studying fresh deer
beds in snow right after you jump a group of whitetails.
Bucks that have learned to use wind often move downwind, especially at night,
using their noses to protect their most vulnerable rear while relying on their
eyes to protect their frontal area. With mature bucks cruising in broad
daylight, those that have learned to use the wind prefer to move quartering
downwind rather than with a nose wind to find ripe does. This allows them
to cover much more olfactory ground while using less energy.
Terrain influences deer movement. The reason the up wind side of a lake will
almost always have more deer movement is due to the fact most deer eventually
learn that danger never comes from out in the lake. Another example: rows of
corn in a field act as baffles to mess up any sideways wind; by the same token,
breezes coming right down rows of corn allow a buck to scent check an entire
corn field by simply walking the downwind edge of multiple rows.
A frequently asked question has to do with whether a hunter should move if, or
when, wind changes direction. Like I already said, I don’t rely too much on
weather forecasts more than two days in advance, but if the local forecast
calls for a given wind direction, I’ll trust meteorologist skills, always
remembering that forecasts are only predictions. If a breeze changes to my
disadvantage, I usually wait things out for at least a half hour before
deciding whether it’s time to vacate. I don’t want to stay on a stand with a
bad wind that does more harm than good by revealing my ambush site. In areas
with quite regular air directional changes, consider erecting two stands on
opposite sides of the area you are hunting. Although we don’t routinely put up
opposing stands, moving across a trail or funnel to an alternate stand doesn’t
take a whole lot of effort if you provide yourself with the option.
Aside from the knowledge that deer always pay attention to wind, don’t forget
they are constantly looking for other deer. Ripe does look for bucks; bucks
look for all deer. Good eyes are one thing, but excellent noses are by far
their strongest defensive asset. They learn to trust their noses infinitely
more than their eyes or ears. If there is one trait that annually saves the
lives of thousands of mature bucks, it is their ability to pay attention to
their noses and use the gift of an excellent olfactory system to avoid trouble
in the first place. Our ability to play the wind might increase our odds but
never really levels the playing field.
Now let’s look at a few of the many factors that affect wind movement against
terrain features and various obstacles in an attempt to try to better
understand how wind is used by deer. Since hunting styles of humans can be
classified as predator types such as canines, felines and raptors, let’s look
at examples. When dealing with whitetail predators, the canine group consists
of wolves, coyotes, bears and dogs. The feline list takes in only cougars, lynx
and adult bobcats. Canines use their noses, eyes and ears to find prey. Felines
depend more on their eyes and ears, with lesser dependency on olfactory skills
except at very close range. Human hunters trust their eyes and ears far more
than our all but worthless noses. For the most part, we humans are essentially
visual predators.
Many years ago, during my apprenticeship days afield, I learned a lot about deer
behavior by watching male dogs interact among themselves in suburban
neighborhoods. Even more information can be noted by watching a good hunting
dog work any piece of cover. Most bird dogs cast back and forth, alternating
between checking ground scent and slightly higher air updrafts. By the same
token, most hounds, with the exception of trained strike dogs, keep their noses
close to the ground to find tracks. Have you ever noticed that flushed birds
often defecate shortly after take off? I watched a wild turkey do it just
yesterday. Many people think the bird just had the crap scared out of it. In
reality, by letting things rip, they are instinctively dropping scent that
causes their pursuer to stop to sniff it, giving the bird an extra few seconds head
start.
We’ve all watched rutting bucks put their noses to the ground to follow a ripe
doe track. We’ve also seen approaching deer stop suddenly on red alert, lifting
their noses higher into the air to get a better whiff of whatever alarmed them.
Chances are it was not enough odor to make them flee, but just enough to
warrant further attention. Why do they lift their noses higher? It has to do
with updrafts in weak air movement. Prey species are constantly aware of the
possibility of impending danger. It’s part of what makes them tick and survive.
They know they can be prey.
One of the biggest advantages of hunting during the rut is that bucks often
forfeit normal caution for that of a juicy doe’s scent. Sexual urges for
reproduction over-ride all natural and instinctive security. They take risks
they wouldn’t normally try. If it wasn’t for man’s understanding of the
powerful urges brought on by the whitetail rut, our hunting success would be
remarkably lower.
Air movement is a very complex subject best suited for people a lot smarter
than me, but a study of basics can help us realize how slight drafts and
stronger air movement around and/or over obstacles can make or break many
hunting situations.
There are a lot of ways for a deer to escape a predator. One is to run fast and
far, taking giant strides in a relatively straight line to gain distance,
hoping any visual or olfactory pursuer quickly loses interest in working out
the trail by use of only its nose. Another tactic is to hold tight, especially
when they’re bedded in thick cover or deep snow. Other than fleeing or holding,
there are also other common ways to shake a pursuer, especially a predator
following by scent. The first is to find other deer and join the group, hoping
their pursuer gets confused and takes off on another track. A second way is to
cross or walk in water to wash away ground scent. A third might call for making
a big loop to cross one’s own tracks. A fourth requires jumping sideways to disguise
an established track. I tend to think a lot of evasive maneuvers are
instinctual but I can’t help but ask myself if any degree of reasoning is
involved. Whitetails are not supposed to be able to reason but they are indeed
born with natural instincts to escape. A newborn fawn instinctively holds
tight, sometimes within feet of a predator. This instinct often lasts less than
two weeks before they learn to jump up to run for all they’re worth instead of
hiding. Untold numbers of fawns are sadly killed by innocent farmers during
mowing. Many people will disagree with me, but I feel coyotes kill more
whitetail fawns than wolves, dogs, bears or cats combined. Most of these kills
occur the first couple weeks after birth but I’ve seen lots of evidence that leans
toward this theory. I’ve even seen coyotes search an area in pairs or small
packs during late May and early June in what appears to be organized specific
hunts for newborn fawns. Fawns are supposedly all but odorless but I don’t buy
the 100% theory. One of the main reasons various species groom themselves or
each other has to do with cleaning themselves of odors. Mammal grooming has
absolutely nothing to do with looks.
I once had a ringside seat to a predator’s quest. I was sitting in a tree one
January many years ago during Iowa’s late season. Two button bucks were feeding
on locust pods in front of me at about 25 yards. Unexpectedly, I saw slight
movement out of the corner of my left eye. I turned slowly to see a huge
male bobcat in full sneak just to my left. He was locked onto the young deer
with sincere intent and was big enough to close the deal if he could close his
jaws on one of their windpipes. His moves were pure poetry. Fluid and perfectly
silent, he froze when he had to, taking careful steps to close the distance
inch by inch whenever he could. I wish I had a camcorder. I was intently
watching the cat when one of the deer obviously smelled or saw him. Both young
bucks exploded with loud snorts to vacate the impending crime scene. I thought
it was interesting the cat just got up, turned and walked away. He didn’t look
or act frustrated or disappointed whatsoever. For him, it was just another
foiled stalk.
Let’s talk about air movement in the woods. Again, always consider it as
invisible water without the effects of gravity. Secondly, remember, warm air
rises, cool air falls. A third rule, just as important but rarely considered,
is how various obstacles lay, what they are made of, their shapes, sizes and
consistency. These are all factors that require attention and can affect
how smells drift through the woods, especially at lower velocities. Above and
beyond structure, terrain and natural turbulence, factors such as wind
velocity, canopy (overstory), ground brush (understory), objects like rocks,
logs, blowdowns, open water, species of trees, trunk size, foliage, and even
shapes of various leaves all play roles in air movement.
Let’s consider a light breeze coming across a relatively flat field bordered by
timber. What happens to air movement is dependent upon many things. Deciduous
trees retaining leaves will affect air differently from those same trees after
they have shed foliage. Tree leaves differ according to species, size, shape,
whether they are brown (dead) or green. Even how leaves hang is a factor as a
result of leaf stems. For instance, quaking aspens have flat stems that lie at
right angles to their leaf, which causes them to shake when air hits two
opposing flat surfaces and gives them the name of “quaking” aspens in the first
place. Other leaves are too big and heavy for their stems and hang almost
straight down. Others, with even heavier stems, only angle their leaves
downward. When low velocity breezes hit drooping leaves facing outward due to
sunlight, air is lifted into a slight updraft directly into the middle of the
tree. As it passes through the tree, the same breeze is then forced downward as
it hits the underside of the hanging leaves on the opposite side, moving air
back downward toward the ground. Now throw in more complex factors such as
higher wind velocities or softwoods versus hardwoods, and we see different
results. The same holds true with softwood species, some of which have branches
slanted up or down at angles dependent upon the species.
Dense brush on a field edge often causes wind eddies that allow a deer
seemingly upwind of you to smell danger. Again, let’s consider air movement of
invisible water as it hits various obstacles like rocks, vertical tree trunks,
horizontal logs, etc. As slowly moving air hits a big rock or large vertical
tree trunk, it accelerates going around the rock or tree, then slows down again
on the back side, causing slight eddies before it moves on. Picture a
huge mound of dirt sitting in the middle of a flat, open field. When a light
breeze hits the hill, most of it will go around rather than up over the top of
the obstacle. But when wind velocity increases, air moves over the hill
as well as around it. Updrafts and turbulence are caused when air flow is
interrupted by structure. There are many rules of thumb that come into play
when dealing with velocity of air movement in any given piece of cover
dependent upon terrain or densities. These rules are often voided when
velocities increase or when structural deviations differ.
Thermals are caused by temperature changes in air. When warm air cools, or when
cool air warms on a hillside, the air flow usually follows vertical drainages,
once again much the same as water would do. Breezes across a large body of
water or at the beach usually come toward shore during the day and move away
from shore at night. When pooled, calm air sitting essentially still in the
woods is eventually hit by a breeze, it spreads in a widening cone that narrows
in width dependent upon the velocity of the wind that moves it. In other words,
the invisible cone is no longer a cone but a narrower band moving directly
downwind with higher wind velocities.
Not even taking into consideration terrain and structure, how air moves through
woods, above the ground but below overhead canopy, is affected by understory on
the ground as well as the size and number of tree trunks and height of the
treetop canopy. Clean, “pretty,” hardwood stands of mature timber won’t affect
winds as much as forest with heavy understory ground brush. As previously
noted, deer wanting to move through areas of calm air will often stop to wait
for subtle changes that indicate its safe enough to move forward.
People who manage land for whitetail habitat frequently suggest thinning of
heavily timbered woods, opening clearings to allow sunlight to filter through
the canopy in an effort to stimulate growth of understory brush. Any increase
in density of ground brush eventually makes very attractive security cover for
deer. This is usually a good plan when clearings are kept fairly small but
remember open canopy often causes down drafts during evenings. When sunlight
warms calm grounded night air on level ground, the warming air rises up to be
replaced by the cooler air surrounding the clearing; not a bad deal for morning
stands. But for evening hunting, when the sun starts to go down, shaded leaves
in surrounding treetops keep air cooler than at ground level, causing light
downward thermals that can give away even an elevated hunter in a treestand. I
suspect many stands hung on the edge of wooded clearings are not very good for
evening hunting even on level terrain due to regular light down drafts. With
higher breeze velocities, this factor is many times voided, but I don’t like to
hunt wooded clearings during calm air until after foliage sheds.
South facing slopes are always better for hunting during cold weather; north
slopes during warm weather. When I lived in Montana, I would always find
September elk on north slopes during warmer weather. South slopes retain heat
longer, allowing more time for updrafts, at least until late afternoon.
On the other hand, north slopes usually have thicker vegetation, providing
better bedding cover and more security against visually sensitive predators on
north slopes, olfactory sensitive prey on south slopes. For these reasons of
rising thermals and warmth, most fawns or elk calves are probably dropped on
south slopes in hilly terrains.
Mature whitetails does habitually
use wind to their advantage when rearing fawns. People who use IR trail cameras
during late June and early July, will notice they hardly ever get photos of
spotted fawns after dark. This is because fawns instinctively don’t move much
during the night when most predators are up and about. I suspect whitetail
fawns remain bedded nightly until they are several months old. You’ll seldom
see a mature whitetail doe go directly to a bedded fawn. Instead, the doe calls
her fawn to her to protect its hiding place and to keep scent to a minimum.
Very few “orphaned” fawns picked up every spring are in fact orphans.
Whitetails regularly use ridge saddles as funnels for movement over a hill. One
of the reasons saddles on ridges become potential hotspots has to do with the
fact a saddle is often the shortest, easiest way for any deer to cross a ridge
without having to climb over the very top. It is also the shortest, easiest way
for wind to get over a ridge, so the second reason a saddle lends itself to be
a prime funnel has to do with drafts of rising or falling thermals. If a ridge
top sits parallel (the same direction) to the prevailing wind, air tends to
move around the ends and along the sides of the ridge unless we’re dealing with
gusty or high winds. By the same token, if breezes come up the sides of a
ridge, at right angles, they pass over the saddles first. Rising warm air seems
to “seek” saddles, probably just because it is acting like water minus the
gravity factor. As warm air moves up or down the side of a ridge, it tends to
follow drainages. These drainages don’t necessarily lead right to ridge
saddles, but often do.
Another tendency noticed with both rising and falling thermals is that they
tend to move in very slight gusts or variable low speeds, not at a steady
velocity. I suspect this has to do with ground obstacles or terrain.
Many ridges have shelves on one or both sides, sometimes more than one,
dependent upon the height of the ridge. If a ridge has a shelf 30 to 50 yards
down from the top, this shelf will be well used by deer. Shelves and resultant
wind eddies make preferred places for bedding and/or for bucks to move along a
ridge. Our problem lies in the fact when these shelves create wind eddies,
especially with downward air flow that comes directly over the top, a waiting
hunter often gets busted. That is probably the reason deer like them in the
first place. Stands erected on shelves usually must be placed higher than
usual.
Eddies also form at the bottom of a
ridge during evening thermal cooling. I often hear, “I used to have a stand
down in the bottom but swirling winds always gave me away.” Swirling is just
another word for an eddy but we must realize that swirling winds can move air
circling horizontally to one side or another but swirling can also move air up
and to your front.
Colored smoke bombs available around the 4th of July are good tools
for off season or non-hunting (scouting) days. I think soap bubbles would be
even better but I’ve never tried soap formulas that make bubbles tough enough
to last very long. I recently learned the secret to making tough bubbles
requires use of distilled water and glycerin, but I’ve not tried any secret
recipes.
Figuring out subtle air movement can become a very complex study because of so
many variables. I’m not saying hunters need to become meteorologists. I’ll be
the first to admit I’m probably not smart or serious enough to figure in
factors like inversion or atmospheric pressure on different days. Understanding
winds and breezes of all speeds that move past any blind or treestand site will
help very much in determining when and how to hunt any particular place. More
often than not, they also explain why we regularly get busted!
