QDMA Articles :
Fawn HarvestingA Logical Alternative for Northern Range
By: John J. Ozoga
The quality of winter habitat and severity of winter weather are
the most important factors regulating deer populations across
much of the northern portions of the whitetail's range. This is
particularly true in the Great Lakes Region north of the 43rd
parallel (roughly from central New York, through northcentral
Michigan, to central Wisconsin), where mild winters allow deer
populations to build up to unusually high numbers, only to crash
later, during the next severe winter. Such boom and bust
cycles probably have prevailed ever since whitetails extended
their range northward behind receding glaciers.
Young of the yearstill referred to as fawns in winterare
the pawns squandered in nature's wicked game of winter survival.
During good times, fawns flourish and represent a high percentage
of the population. However, during harsh winters, they are the
first to diesometimes by the hundreds of thousands.
Why Harvest Fawns?
There are some good biological reasons why hunters could and,
in some situations, should harvest more fawns on extreme northern
ranges:
1. Fawns generally represent the most numerous single age class
in the population. More fawns typically survive to weaning age
than are needed to replace adult mortality.
2. Fawns contribute little or nothing in the way of reproduction
the following year. So their harvest has little impact on annual
recruitment rates.
3. Fawns are always underrepresented in the annual harvest.
Given a choice, hunters generally harvest an antlered buck or
a doe, instead of a smallbodied fawn.
4. Fawns are the most likely to die during harsh winters. Even
during years of high reproductive success, there is no guarantee
that a high proportion of the annual fawn crop will survive their
first winter and be available for harvest as yearlings.
Being SmallGood or Bad?
Fawns typically are smaller than adults, which presents certain
advantages as well as disadvantages. Cornell University scientist
Dr. Aaron Moen points out that fawns entering the winter at belowaverage
weights have certain laws operating against their chances of survival.
Based on Moen's calculations, More heat is lost by convection
(air movement) from a square meter of surface of a small deer
than from a square meter of surface of a large deer.
The critical body weight for fawns lies somewhere between 77 and
88 pounds. Animals below this range lose considerably more body
heat, and are less likely to survive extended periods of cold
weather. By comparison, larger deer are more efficient in terms
of energy conservation. In the South, small fawns often are the
result of late births. These fawns may actually experience a metabolic
advantage because of their lower food requirements and survive
in high numbers where mild winters are the norm.
In contrast, small fawns in the North are more commonly the product
of poor summer and autumn nutrition. For them, poor nutrition
during the snowfree months is invariably followed by extremely
stressful and impoverished food conditions during winter. Few
of these stunted and comparatively lean fawns are likely to survive
such hardship.
Winter Mortality
The recent winters of 199596 and 199697 will long
be remembered as real deer killers throughout the Upper Great
Lakes region. During those two particularly tough winters, an
estimated 310,000 whitetails died in Upper Michigan alone. Roughly
half of them were fawns. Even during moderate winters, fawns represent
8090 percent of the total winter mortality. When coupled
with browsedepleted winter range, the loss still can be
sizable in highdensity deer herds containing many malnourished
fawns. In Upper Michigan, for example, the annual death toll of
whitetails during the mild winters of the late 1980s and early
1990s matched or exceeded the area's legal rifle harvest, which
ranged between 40,00055,000 deer, annually. Ironically,
such winter mortality occurs largely during late winter and early
springonly after each deer already has consumed a large
quantity of valuable browse and further degraded the winter habitat.
Fawn Tagging Studies
Studies conducted in Upper Michigan's Petrel Grade Deer Yard revealed
high natural mortality of fawns during their first winter. Although
fawns represented only about 30 percent of the yarding herd, they
accounted for about 60 percent of the total mortality.
Of 145 male fawns we livetrapped, tagged, and released in
the yard, only 47 (32.4 percent) were ever reportedly killed by
hunters. We had no information on female fawns because of very
limited antlerless harvesting in the area. More recently, similar
recovery results were found when biologists examined more than
250 male fawn tagging records from various deer yards throughout
central Upper Michigan. In fact, the return rate of tagged animals
was an identical 32 percent. Certainly, not all tagged animals
shot by hunters are reported. And, some bucks survive their first
winter only to succumb later to other mortality factors. Nonetheless,
the available evidence strongly suggests that, on average, only
about half of all fawns survive their first winter in Upper Michigan.
Telemetry Studies
Even during very mild winters, studies conducted by Dr. Timothy
VanDeelen revealed comparatively high overwinter fawn death rates
in Upper Michigan's Whitefish Deer Yard. During three mild winters
(1992, 1993, and 1994), 32 percent of buck fawns and 28 percent
of doe fawns fitted with radiocollars died from natural causes
during their first winter.
In northern Wisconsin, Dr. Orrin Rongstad also found overwinter
fawn mortality rates highly variable. During some very mild winters
none of his radiocollared fawns died; whereas, as many as
44 percent died during some severe winters.
The Bambi Complex
From a management standpoint, it is unfortunate we call them "fawns."
Even when they are seven or eight months old, and even when some
are sexually mature, they are still fawns in the eyes of most
wildlife biologists, educated hunters, and the general public.
Educated hunters typically distinguish deer as being fawns, yearlings,
or adults during the autumn hunt. On the other hand, hunters who
know very little about deer biology, recognize only bucks and
does. For them, female fawns become small does, whereas
male fawns are button bucks or knobby bucks.
Even knowledgeable hunters will resort to such terms to minimize
criticism for shooting a fawn.
Regardless of their size, the term fawn has a certain
stigma attached to it. The general public often envisions them
as being innocent, spotted creatures hardly able to toddle on
wobbly legs. Regardless of their size, to some, the term fawn
is synonymous with Bambiafter all, who would
want to shoot an innocent Bambi?
The idea that fawns could and should be selectively harvested
on northern range is nothing new. In 1975, Dr. Orrin Rongstad
issued a University of Wisconsin extension news release entitled,
Shoot Fawns to Help the Deer Herd. In this release,
Rongstad criticized hunters for not shooting more fawns, suggesting
that starvation losses and waste would be reduced on northern
range if hunters selectively shot more fawns. He added, Because
hunters with antlerless permits shoot larger animals, the ages
of the animals hunters kill differ from the age structure of deer
dying during a severe winter. So, killing a deer during the hunting
season does not necessarily prevent one from starving during the
winter. In fact, Rongstad proposed that hunters who shoot
a fawn should be rewarded in some way, not condemned. They're
helping the deer population, he argued, more so than
hunters who kill larger, older animals instead.
Despite the biological soundness of his proposal, Rongstad was
blasted by the ecologically ignorant press for advocating such
a revolutionary deer management strategy. Even some wildlife professionals
slammed Rongstad, not on biological grounds, but for political
reasons. The sentimental and emotional public just was not ready,
neither were deer managers, who were more concerned with providing
quantity instead of quality. Deer hunters, who were more concerned
with trophies on the wall or large quantities of venison in the
freezer, also were not ready.
Conclusions and Management Implications
As with many aspects of deer management, the application of this
research depends on your individual situation and management objectives.
If your deer population is at or near the carrying capacity of
the habitat (i.e., too many deer), and your goal is to reduce
the population, then harvesting adult does, rather than doe fawns,
is advised. This reduces the number of breedingage does
and, following the additional natural fawn mortality during winter,
the reduction in the population will be maximized.
In contrast, if your population is below the carrying capacity
of the habitat, and herd stabilization is your goal, then harvesting
fawns, particularly doe fawns, is recommended. Such a harvest
mimics natural mortality, makes wise use of a vulnerable and precarious
surplus, and has little impact upon the size of next years
deer herd. This also would lessen browsing pressure in critically
important deer yards.
The harvesting of buck fawns is somewhat more complicated. Given
that most practitioners of Quality Deer Management attempt to
maximize the number of mature bucks in a population, the harvest
of buck fawns is generally not recommended. However, in extreme
northern ranges, many buck fawns will succumb to natural mortality
even when protected from legal harvest. As such, protecting buck
fawns in these areas will have minimal effects during years of
extreme winters. However, during mild winters, protecting buck
fawns may increase the number that survive the winter and enter
the population the following year as yearlings. In either case,
a buck fawn is far more "expendable" than a yearling
buck if a harvest decision between the two must be made.
In conclusion, harvesting fawns on extreme northern ranges is
a logical alternative to massive winter deer mortality and further
deer yard degradation. It could be safely implemented even in
areas of low deer numbers where no antlerless deer hunting currently
exists. Surprisingly, neither educated hunters nor trained biologists
have advocated this harvesting strategyeven in the face
of recent massive winter dieoffs. I cannot help but wonder if
the day will ever come when scientific reasoning, instead of human
emotions, determines deer management direction?
Mr. John Ozoga is a former Wildlife
Research Biologist for the Michigan Department of Natural Resources.
He spent more than 30 years conducting deer research at Upper
Michigans Cusino Wildlife Research Station. He now devotes
much of his time to consulting and popular writing and serves
as Research Editor for Deer and Deer Hunting magazine.
Portions of this article were reprinted with the authors
permission from a previous article in Deer and Deer Hunting magazine.
Back
to herd management