Transcript Whitetail Deer

Whitetail Deer
Model Organism for Biological Principles
Whitetail History
Deer originally occupied the
transitional forest zones and prairies.
Deer were scarce in the coniferous
forests of Northern Minnesota. Moose
and Woodland Caribou were found
there.
Around the turn of the century, logging
took the pine and were replaced by
hardwoods thus expanding Whitetail
range. There are actually more deer
now than ever before.
Now, they are the #1 big game animal
hunted in the united states.
Whitetail Traits
• Senses –
– # 1 sense of smell. (can
smell odors up to 1/2
mile away)
– # 2 hearing
– # 3 eyes (not good, but
can detect motion well.
They can perceive some
color, cones found in
retina.)
Whitetail Traits
• FEED
– 1. Browse: buds and twigs
from small trees
– 2. Graze; grasses, rye,
clovers, alfalfa, oats, wheat,
corn, acorn, apples, salt
licks.
– gain weight in the fall for
winter months.
– bucks will go with out food
during rut. (May lose 20
lbs.)
Whitetail Traits
• RANGE
– Does (female): average range - 1/6 square miles.
– Bucks (male): average range - 1 2/3 square miles.
Whitetail Traits
• MOVEMENT:
– Nocturnal - move at night
– Crepuscular: feed mostly before sunrise and after sunset.
Day trails - woods and brush (look for them here)
Night trails - fields, meadows, crop lands. (seldom used during the daytime.)
• move between resting and feed sites.
• more movement during rutting process.
• bed down a midday.
• deer move about more when weather is warm rather then cold. clear
rather then cloudy.
• deer lay low during rain, snow and wind. They move rapidly before and
after storms.
• spooked deer may not run as far as you think and are worth going after.
• if a doe is spotted, wait for a possible buck to follow.
Seasonal and Habitat Relationships
• In spring deer move out of
this winter cover and into
edges and open areas for
feeding on the greenery
that is rich in protein.
Seasonal and Habitat Relationships
• Winter is the season of hardship. Shorter days
triggers change in metabolism. Deer enter a
state of semi-fasting that results in lower food
needs. Deer need fat reserves to survive most
winters.
Deer will remain in conifer cover during severe
winter weather instead of expanding energy
looking for food. Deer will “Yard Up” providing
well packed trails in deep snow.
Seasonal and Habitat Relationships
• Deep snow and cold temperatures
over long periods of time drain a
deer’s energy. A severe winter
followed by late spring green up may
cause starvation and lower their fawn
production.
• Successive severe winters contribute
to fluctuating deer populations in
Northern Minnesota just as
subsequent mild winters contribute
to healthy her numbers and even
problems with over population.
WSI = “Winter Severity Index”. A measurement of how severe a winter is on wildlife.
Days with snow 15 inches or more or temperature below zero = 1 pt. (2 pts)
Dec. 1 – April 30
0 – 50 points = mild winter for wildlife
50 – 79 points = moderate winter for wildlife
80 - 99 points = Severe winter.
100 + points = Very Severe
Winter of 1995-96 had a WSI of 202. Closed deer season up north next year.
Bergmann’s Rule #1: An animal’s body increases in size the farther North it lives.
Bergmann’s Rule #2: An animal’s appendages decrease in size the farther North
Florida Key Deer
Arctic Fox
.
Whitetail Physiology – Rutting Season
• Triggered by photo period (change of light)
pituitary gland signal tests to release
hormones.
November 10, Peak rut in Minnesota.
Does go into estrous for 1-2 days. If not breed,
they will repeat in December.
When is estrous, does will walk with
their tail up or out and to the side.
Whitetail Physiology – Antlers
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purpose is secondary sex characteristic.
sexual adornments
bluffing attempts in battle for mating.
bucks of same size rack will tangle for mating rights.
paths of the veins in the velvet called GUTTERS can
be traced in the hard antlers.
Whitetail Physiology – Rutting Season
SIZE OF ANTLERS IN DETERMINED BY:
1. Health of deer
2. Available food
3. Genetics
4. Approximate age
Whitetail Physiology – Rutting Season
NON-TYPICAL ANTLERS
-malfunction hormonal secretions
-damage to velvet
Records of does with antlers- mixed up hormones. (testosterone
regulates rack production in both male and females.)
Hunting Deer
Scents: smell is # 1 sense.
Different types of scents that appeal to
deer:
1. territioral: deer will notice a new
animal in his territory. (urine, glands.)
*challenge scents
2. hunger: appeals to the deers sense of
hunger. (apples, acorns)
3. curiosity: new smell to deer, so they
will investigate. good to use early in
season.
4. sex: good during rut. (doe urine)
5. cover: mask human order. (skunk, fox
urine) most scents will mask human odor.
HUNTING STRATEGIES
Scouting: look for signs before season opens.
-trails
-browse
-rubs - rubs on small trees. early to remove velvet.
mark with pre orbital gland to mark territory.
size of rub and size of tree often determines size of deer.
bucks seldom return during rut.
-scrapes - scrapes on ground. bucks scrape and leave urine and
inter-digital scent on scrape to mark territory and to attract
doe.
size of scrape determines size of buck.
-track - sharp edges - fresh track
- round edges - old track
- both bucks and does will drag toes when walking. usually
bigger deer will drag. (more often bucks)
-beds - size of bed determines size of deer.
Hunting Styles
• STAND HUNTING
up in tree. game usually does not look up.
-use scent to hide your order or attract the
deer.
your scent may rise in morning and drop in
the evening due to air temperature. tree in
morning, ground in evening.
-locate a stand in a “funnel” where
woods/brush narrows forcing deer to you.
(find trail, scrapes etc.)
-comfort, warmth necessary for duration. stay
in stand for at least three hrs
Hunting Styles
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STILL HUNTING
Walking slowly (silent)
Move slowly (one step then wait 2-5
minutes) stop, listen, look
-good midday technique when game are
inactive. deer will let you pass if
walking at a pace
-walk into wind
-careful placement of feet - snap
twigs/leaves
-soft clothing reduces noise
-deer will often run behind you.
-two person still hunt: have one
person in front of other to guard
against deer running behind leader
Hunting Styles
• STALKING
-different from still hunting in that you know that game exists in a particular
location.
-sneak within shooting range.
-stay low to ground and behind cover if possible
-if deer lifts its head and looks, stop.
Hunting Styles
• DRIVING
effective way to push game out of a large area.
“posters” position at end of cover by “escape route”
“drivers” spread out according to density of cover.
-keep game from doubling back
-know location of others. visible.
*start at widest part of cover and work to narrower.
-game will stay in cover until end or will run out sides.
-use unusual sounds, erratic movements, vary walking speed stop, turn back, etc.
safety know position of all hunters.
Carrying Capacity
• The number of individuals a
habitat can support.
• Measured in late winter.
Example:
-Farm supports 50 pheasants in
summer but 20 in winter.
-Remaining 30 will die.
-An attempt to stock birds
above carrying capacity
is fool hearty.
Limiting Resources
• a factor that controls a process, such as organism growth or species
population, size, or distribution. The availability of food, predation
pressure, or availability of shelter are examples of factors that could be
limiting for an organism.
• Examples?
Regulated Hunting
•
Game Managers can utilize hunting as a tool to
help control the numbers of certain game species of
animals. With the use of hunting regulations animal
populations can be held in check to the benefit of the
species. Rare or endangered species are protected as
are non game species.
•
Some hunting is done not as a management tool,
but as a recreational endeavor. Most hunters have
strong ethical values related to their sport.
•
Money (millions of dollars) generated by hunters
through license fees and stamps as well as excise tax on
hunting equipment is useful for game management
programs.
Regulated Hunting
Market Hunting
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At the turn of the 19th century, in the
United States, animals were killed for profit.
Some sold to restaurants, others used to feed
rail or logging camps. Government regulations
prohibit this practice today and animal
populations have rebounded nicely.
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The unregulated trapping of Beaver in the
1700s almost led to the animal’s demise. A fad
in Europe for hats made from the fur is what led
to the exploitation of the animal.