Download Hill Country Wildlife Management December 2016 Submitted by

Hill Country Wildlife Management
December 2016
Submitted by Chris Cook, member of the Fair Oaks Ranch Wildlife Education Committee.
We are fortunate to live in Fair Oaks Ranch, a property with a rich heritage and one rich in wildlife
of all types that we enjoy. While some of the “tools” discussed below are not available within
the municipality, or even appropriate to be applied in a more urban area like our own, this Texas
Parks and Wildlife article, written with a historical perspective, is interesting and in many ways
still relevant today. It describes the complex ecosystem of the Texas Hill country, and how it has
changed over the years, both as a result of natural cycles and man’s presence.
Habitat Management
The border above illustrates 5 basic tools (axe, cow, plow, fire, and gun) used traditionally for
managing wildlife communities. The key to managing natural resources is to use a holistic
approach, where all of these Tools are applied to develop and maintain healthy ecosystems.
Single species deserve less attention, while the system in which they thrive requires more.
Knowing how that system functions, and applying the techniques with which that system
developed (e.g., moderate cattle grazing, prescribed burning, hunting) is imperative for its
continued existence.
Axe
As discussed in Historical Perspective, the expansion of Ashe juniper (cedar) has had
a tremendous impact on the ecosystem, causing a decrease in plant species diversity and an
increase in soil erosion. Cedar brakes lose a significant amount of precipitation through
transpiration and overland flow, leaving much less water for aquifer recharge.
Landowners have been cutting cedar for years, and continue to find out that one treatment is
good for only a few years. Ashe juniper, or blueberry juniper, which is found throughout the
eastern and central Hill Country, dies when the tree is cut. However, since the soil is full of
juniper seeds, the landscape is due for another treatment after 7-8 years. Redberry juniper,
located in western Hill Country, re-sprouts from the root system after the tree is cut. Thus,
treatment of this variety is necessary at more frequent intervals.
Initial treatment of cedar stands requires mechanical control. For years, cedar was removed by
pushing (with bulldozers), and chaining. Such methods can be quite destructive since this region
of Texas has such shallow and rocky soils. As trees are pushed over, rocks are usually pushed
to the surface, leaving no substrate to support ground cover. As a result, remaining soil is
washed away and only rocks remain. Generally, you can expect 50,000 years to pass before the
rocks turn to soil. As these consequences became more apparent, some turned to hand cutting.
While hand cutting allows for selective removal of trees, and causes little or no soil disturbance,
it is a very slow and expensive process.
Fortunately, today we have hydraulic shears, which allow for selective removal, minimal soil
disturbance, and efficient work. Many claim that they can remove at least as many trees with
shears as they can with dozers, in the same period of time. Furthermore, the cost of shearing
is no more than the cost of other methods. Rates tend to range from $55-75/acre, and operators
cut an acre/hour in flat to gently rolling terrain.
Following are some considerations of major importance when planning a brush management
program:
 The
program should not adversely impact endangered species or their habitat.
 Extreme
 The
care should be taken to insure that too much wildlife cover is not destroyed.
method used should improve wildlife food supply and habitat.
 Removal
of desirable plant species should be minimal.
 The
program should be economically feasible and comply with overall goals of the
management plan.
 Plant
diversity and general health and vigor of the range should be increased.
 Areas
which support winter turkey roosts should remain totally intact.
 Treatments
that disturb soils should not be applied to highly erodible sites
Cow
Bison roamed the Hill Country through mid to late 1800s, leaving quite an impact on
the landscape. Historical reports indicate that bison herd were strung-out 90 miles in length, as
it took 3 days to travel from one end of the herd to the other. One report mentions that settlers
traveling from Fredericksburg to Mason, had to turn back because there was not enough grass
left (after the bison moved through) to feed their horses. While such grazing pressure left a lot
of tilled soil, resting periods (of the rangeland) were sufficient to allow for rapid responses of
annual forbs (weeds & wildflowers) and grasses. Resulting was more plant diversity and more
wildlife foods. Bison opened stands of dense grasses, providing more food for deer, turkey,
quail, prairie chicken, and songbirds. Undoubtedly, bison grazing was a major force that shaped
the ecosystem.
European settlement thrived during the "Golden Period" when grasslands were lush and seemed
capable of supporting an unlimited number of livestock (cattle, sheep, goats, oxen, hogs,
horses). More normal years followed, when rainfall was scarce and overgrazing was common.
This resulted in abused rangelands lacking adequate groundcover and available browse to
support healthy livestock and wildlife populations. Mid-grass and tall-grass communities were
replaced with short-grass communities. Overgrazing with domestic livestock continued through
the 20th century and many rangelands continue to suffer.
As Aldo Leopold wrote in his 1933 textbook titled Game Management, "...game can be restored
by the creative use of the same tools which have heretofore destroyed it - ax, plow, cow, fire,
and gun." Leopold often referred to the "cow" as an effective wildlife management tool. Cattle
can be used as a tool to manipulate and enhance wildlife habitat and plant diversity (as bison
did). The main role of grazing in a wildlife management program is to reduce the quantity of
grass, allowing sunlight to reach the lower growing forbs, which are important wildlife foods.
Furthermore, this process creates more structural diversity, which is more conducive to nesting,
brood rearing, and hiding.
Range improvement can be attained through proper grazing rates and by scheduled rest periods
to allow pastures to be free of grazing by domestic livestock. Rotational grazing systems should
allow pastures to be rested (deferred) during a specified time of the year. Some examples of
grazing options in order of preference are: a short duration or "time control" system; a high
intensity - low frequency system (HILF); a 3 pasture-1 herd system, and the 4 pasture-3 herd
rotational grazing system. Each requires different degrees of involvement and fencing.
Plow
Tilling the soil is another approach to setting-back plant succession and promote the
growth of desirable wildlife foods (forbs). As mentioned above, bison tilled the soil as they
grazed through areas, promoting more plant diversity. While used extensively in other parts of
Texas, methods of soil disturbance generally are not recommended in the Hill Country, as the
shallow, rocky soils are highly vulnerable to erosion. Food plots are difficult to establish,
especially during stressful years when they are most needed. Therefore, wildlife management
in the Hill Country typically involves only 4 of the tools, excluding the "plow."
Fire
Bison were not the only force shaping the system in which pronghorn antelope, black
bear, wolf, white-tailed deer, turkey, quail, and prairie chicken thrived. Fires, natural and manmade, played an integral role in managing that system. Since the 1850s, man has suppressed
fire, and the grasslands that were once dotted with an occasional live oak motte have been
replaced by parklands and woodlands. Ashe juniper has spread from the steep draws and
canyons and exploited the uplands.
A prescribed burn program that is used properly with a grazing deferment program and deer
harvest management, is an effective tool for managing wildlife habitat. Burning increases plant
quantity and quality, and enhances habitat diversity. Many plant species are tolerant of fire.
Others require fire for adequate germination. Cedar is not a fire tolerant plant. It was controlled
by the frequent wildfires that occurred before European settlement. Europeans suppressed fire
to prevent damage to wooden structures, farmlands, fences, and grazing lands. That eliminated
or reduced the role that fire played in maintaining an ecosystem that was not dominated by
cedar. Formerly restricted to steep rough areas where fire couldn't reach, cedar is rarely eaten
by deer or livestock and quickly invades all sites in the absence of fire. Controlled fire (prescribed
burning) reduces regrowth cedar, but rarely harms mature cedar, the home of the endangered
golden-cheeked warblers, and encourages the growth of deciduous trees preferred by blackcapped vireos.
Burned pastures can be grazed immediately to reduce grasses that compete with forbs, then
deferred to allow the pasture to rest. Whitetail and exotic wildlife numbers may have to be
reduced prior to burning to allow preferred plants to reestablish following prescribed fire.
Portions of the property should be left in permanently unburned cover to insure that plants
intolerant of fire are part of the ecosystem diversity. A burning schedule should be maintained
to give priority to burning in the winter and early spring before green-up. Even with the best
planning, burning "windows of opportunity" always depend on humidity, wind, and fuel moisture.
The inexperienced manager should ask for assistance and/or advice from agencies such as
TPW or the NRCS. While instructional materials are available, it is suggested that the novice
assist on a burn conducted by an experienced person before attempting the first controlled burn.
Gun
The period between 1900-1940 saw a growing deer herd with large bodied, well
antlered animals. Deer foods were relatively abundant. Around the 1940's, the deer herd
overpopulated its range. The combined grazing pressure of too many deer, sheep, goats, and
cattle again changed the vegetative patterns of the Hill Country. Thereafter, die-offs began to
occur at 5 to 7-year intervals. Every year, the Hill Country loses 20-40% of its white-tailed deer
population to malnutrition. As one deer biologist states, "We probably have the best buzzard
management program in the world, and we're feeding them white-tailed deer. Mature Hill
Country bucks field-dressed around 200 pounds in the early 1900s. Whereas a decent mature
buck today weighs around 120 pounds. What's the problem? There are too many deer, and not
enough groceries.
Areas with higher deer densities have lower fawn numbers, more major die-offs, smaller body
weights, and poorer quality antlers. These symptoms are a result of abused rangeland, where
white-tailed deer (and often exotic deer and domestic livestock) have eaten all available forbs
and browse. Such rangelands have poor plant diversity and are dominated by cedar,
persimmon, and prickly pear cactus. Consequently, such areas have poor wildlife diversity. The
whole system is suffering, as soil is washed away and more rock is exposed. There is no
groundcover to capture runoff, and rain water is lost.
The axe, cow, and fire do little good when deer numbers remain at horrendously high levels.
For rangelands to respond to these various management practices, deer must be harvested and
maintained at or below the carrying capacity of the land. This recommendation includes
(emphasizes) the harvest of antlerless deer (does).
Summary
Today, it is very important that land managers understand basic ecological principles of plant
succession, plant growth, food chains, and water, mineral and soil nutritive cycles as they affect
range, wildlife, and grazing management. In addition we should know and recognize the basic
needs and preferences of the livestock and wildlife species for which we are trying to manage.
It is equally important to manage for a high level of plant succession and quality wildlife habitat
using the basic tools of grazing, rest, fire, hunting, animal impact, disturbance, and technology.
This not only produces high quality habitat and animals, but also can lead to more stable
conditions during stress periods such as droughts and winter.