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.