http://www.newwest.net/topic/article/
hunting_and_predators_does_it_work/C564/L564/
Hunting and Predators--does it work?
By George Wuerthner, Unfiltered 11-11-10
Hunting and Predators--does it make Sense?
As many readers may know,
wolves were recently relisted under the Endangered Species Act (ESA)
removing management authority from state wildlife agencies in Montana,
Wyoming and Idaho. The strongest voices opposing further protection of
wolves have come from ranchers, hunters, outfitters, and hunter organization
like the Rocky Mountain Elk Foundation. They are demanding that the ESA be
amended to allow sport hunting in the northern Rockies.
These
individuals and organizations argue that wolves need to be hunted and
managed 'like other wildlife.' Proponents of wolf hunting argue that wolf
numbers are too high and are a threat to the livestock industry as well as
elk and deer populations. They also suggest that without hunting, wolves
will 'lose their fear of man' and rampage through towns and villages
snatching up child and adults. In other words, unhunted predators are a
threat to human health and prosperity.
Underlying all these assertions is
the assumption that hunting will reduce human conflicts. One might presume
that given the strong support for hunting that there is a lot of scientific
evidence to buttress the contentions that hunting reduces livestock losses,
increases prey abundance, and reduces predator attacks on humans.
Unfortunately there has been little research to date that tests these
assumptions, and is a growing body of evidence suggests that indiscriminate
predator control, whether due to sport hunting or by predator control
agencies like Wildlife Services, has the opposite effect and actually
increases conflicts between humans and predators.
A self fulfilling
feedback mechanism results whereby state wildlife agencies institute hunting
of predators, creating more social chaos, which in turn leads to greater
human conflicts, and more demands for even greater predator control.
For
instance, Adrian Treves writing in a review of hunting effects on large
predators in the Journal of Applied Ecology concluded 'the direct impact of
hunting on conflicts with carnivores over game and property damage is unclear
and even doubtful given the inability or unwillingness of hunters to remove
specific individuals selectively.' In other words, hunting if it works at all
is a very blunt and ineffective 'tool' for alleviating real and/or perceived
conflicts between predators and humans.
Another study which looked at
hunting of bears in five states and one Canadian province found that as bear
deaths rose as a consequence of more liberal hunting regulations, so did
conflicts with humans. As a comparison, the authors also reviewed bear-human
conflicts in unhunted bear populations where education and changes in human
behavior were implemented such as use of bear proof garbage cans, and found
that even as bear numbers increased, human conflicts decreased
significantly. They concluded that bear hunting was an ineffective means of
reducing conflicts.
Perhaps the best control we have on the effects of
hunting on predator-human conflicts is California. In 1991 California voters
passed an initiative that outlawed hunting of cougars. Today California has
more cougars (about 6000) than any other western state, yet has the lowest
per capita rate of cougar attacks in the West. In other words, in states
where cougars are hunted so they presumably 'fear man' there are far more
cougar attacks on people than in California--even though California has more
people, and more cougars than any other state--thus should, statistically
speaking, have much higher per capita cougar attacks.
California also
has one of the lowest livestock losses in the West attributed to cougars as
well suggesting that hunting is ineffective at reducing conflicts with
ranchers'in fact the evidence suggests that hunting actually increases
livestock losses in many instances.
In the latest year for statistics
(2009) California Fish and Game removed (i.e. killed) only 42 cougars in the
entire state. This is very conservative compared to the hundreds killed
annually in other western states that permit hunting yet have far lower
cougar populations. For instance, Oregon hunters killed 247 cougars in 2009
and this number does not include the cougars also killed by Wildlife
Services for livestock depredation and/or human safety. Yet Oregon with a
human population 1/10 the size of California reports far more human/cougar
conflicts than California.
Another recent study of cougars in Washington
found a similar relationship. As cougar hunting was intensified by the state
wildlife agency, and researchers were able to document that the cougar
population was actually in severe decline, yet complains and conflicts
between humans and cougars actually increased.
What's going on here?
The answer is that large predators like cougar, bears, and wolves are social
animals. And indiscriminate hunting disrupts predator social relationships
creating social chaos. Just as humans living in a war zone resort to
desperate means to survive including stealing, robbing, illegal trade,
prostitution, and what have you, predators respond to social disruption in
ways that results in more human conflicts. One explanation is that hunting
skews populations towards younger animals. Younger animals are less skillful
hunters, and more likely to travel greater distances either in hunting
and/or looking for a territory to occupy, thus putting them in potential
conflict with humans.
State agencies reassure citizens that they will maintain predator
populations, but ignore predator social ecology. It's possible to have the
same number of predators and yet create social chaos by sport hunting. For
example, unhunted wolf packs tend to be more stable and have a higher ratio
of adults to pups. A stable wolf pack with older more experienced hunters is
more effective at finding prey. Plus a larger pack can more easily defend
and hold a larger territory which means that overall predation pressure on
prey species is lessened since some portions of that territory are lightly
hunted providing a refugia for prey.
By contract, in heavily hunted wolf
populations, the packs tend to be smaller, with fewer experienced adult
hunters, and a higher proportion of pups to feed. Plus smaller packs are
less able to defend a stable territory thus are more likely to be hunting in
new unfamiliar territory. With more packs you may get a more effective
coverage of a limited geographic area increasing overall predation pressure
on prey.
To illustrate imagine an unhunted wolf population with 15 pack
members consisting of 10 and five pups of the year occupying a territory of
100 square miles. The 10 adults can easily provide food for the five pups,
plus more easily hold and defend a territory.
In a hunted population you
could have the same 15 wolves also hunting the same 100 square miles, but
perhaps broken up into 3 packs of five wolves each consisting of 2 adults
and 3 pups in each pack. The average age of wolves in hunted populations is
considerably younger than in unhunted populations. Younger wolves are less
experienced at hunting and thus are far more likely to attack easy prey like
livestock. In addition, the three packs may more completely and regularly
patrol the 100 square miles of occupied territory thus leaving fewer refugia
for prey.
In our imaginary hunted packs, there are two adults per pack. These two
adults have a much more difficult time providing food for the pups than the
ten adult hunters in the unhunted wolf pack, especially since one adult
typically remains with the pups while the other adult is hunting. A single
wolf has a difficult time bringing down large prey like elk. As a
consequence the hunted wolf packs are much more likely to kill easy prey
like livestock.
And worse for hunters, small packs cannot consume an
entire elk in one night. And scavengers like ravens, coyotes, grizzly bears
and so forth can move in and clean up a carcass in a single night forcing
the pack to go out and find another elk or deer immediately. While a larger
pack can more easily guard its kill and consume it more completely.
In
addition, growing pups are like teens everywhere. They eat a lot of food for
their size. The 15 wolves in three packs have 9 pups to feed compared to the
5 pups in the unhunted population, thus ultimately hunted wolf packs may
kill more elk and deer biomass to feed their pups than a more stable
unhunted population.
Finally the assertion by hunters that predators will
'destroy' hunting is overblown and exaggerated. While there is no doubt that
wolves and other predators can depress game populations in some places, such
population declines are not a threat to hunting. In Minnesota which has more
than 3000-3,500 wolves (also protected by the ESA) and where wolf numbers
have been consistently higher for a much longer time there are more than a
million whitetail deer, and hunters regularly kill between 150,000 and
200,000 deer annually. This despite the presence of more than twice as many
wolves as are found in the entire Northern Rockies (approximately
1600-1700wolves spread over three states). Obviously hunting did not
disappear in Minnesota as a consequence of wolf predation.
Even where and
when predators appear to depress ungulate numbers (elk and deer) it should
not be characterized as a 'problem' as commonly portrayed by state wildlife
agencies or hunting organizations. Recent research on the effect of wolves
and other predators on elk and other herbivores numbers suggest that
predators can sometimes change game habitat use and numbers, however, the
overall effect is often positive for the landscape. A reduction in herbivore
pressure results in an increase in browse such as willows and cottonwoods,
providing for more songbird habitat, more stream riparian stability and
restoration--hence trout habitat--and an increase in beaver.
The presence
of wolves can also influence other predators. For example, in areas with
high wolf numbers, coyotes are reduced. And since coyotes are the major
predator on pronghorn fawns, an increase in wolves' results in higher
pronghorn fawn survival. These positive changes and many others we unlikely
do not even know about at this time results from the presence of predators.
In other words, if we want wolves to have any ecosystem influences, we must
manage predators for maximum populations, not minimum numbers as advocated
by many hunting organizations.
Furthermore, when state wildlife agencies
increase hunting effort of predators by adopting more liberal seasons and
take of animals in an effort to reduce human/predator conflicts, they ignore
the geography of hunter effort. Hunters generally do not target the very
animals of most concern--i.e. those animals habituated to life near human
communities and/or preying on livestock located on private lands. There is a
logical reason for this. Hunters tend to hunt the larger blocks of public
lands, not the fringes of towns where one may find habituated predators as
well as the private lands where livestock killers are likely to roam.
To
sum up hunting is an ineffective means to reduce human/predator conflicts.
In fact, a growing body of scientific research (largely ignored by state
wildlife agencies) suggests standard wildlife management predicated on sport
hunting increases human-predator conflicts and threatens long term ecosystem
health. You cannot 'manage wolves like other wildlife.' Indeed, the best way
to 'manage' wolves and other predators is not to kill them at all, except
perhaps for the rare surgical removal of a few chronic livestock killers or
the occasional animal that become habituated to humans.
__________
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GEORGE WUERTHNER'S "ON THE RANGE"
George Wuerthner
A blog about the
West's public lands, ecology and public policy.

George Wuerthner is an ecologist, writer, and photographer. He has a
particular love for the western United States, having lived for varying
periods of time in Missoula, Bozeman, Livingston, Boise, Challis,
Grangeville, Sheridan, Anchorage, Tok, Beetles, San Bernardino, Santa Cruz,
and Eugene. Wuerthner worked as a hunting guide, high school teacher,
college instructor, and natural history/wilderness guide in Yellowstone and
Alaska. He has also held a number of jobs with federal agencies including
positions as surveyor, forestry technician, range technician, botanist,
biologist, park ranger and river ranger. Since leaving graduate school, he
has published 34 books on geography, national parks, wilderness,
conservation history and environmental issues. In researching those books,
he has traveled extensively throughout the western US and has been to every
major mountain range in the West. He has a particular interest in public
lands, and wildlands. At one time or another he has visited every major
western national park unit, including all of the monuments, preserves and
parks in Alaska, every national forest in the West and the majority of BLM
lands, as well as more than 380 designated wilderness areas across the
United States.