Wolves conjure up many emotions and stereotypes. The wolf has been used throughout history in legends and tall tales that have shaped our concept of the wolf. Science cannot dispute tales handed down through time, but it can deal with the myths in current times. There are three main issues related to wolves and wolf recovery that tend to generate the most controversy.
In each case,
people's opinions tend to be shaped as much by myth and hearsay
as by scientific and historical data. Wolves are one of the most
studied species in the animal kingdom, and so the scientific knowledge
of them is plentiful. In
this section of the Forum’s website, the distinction between
myth and truth about wolves and wolf behavior will be examined.
Relying on available facts, both scientific and historical,
we discuss how this knowledge may help us to predict what will happen
in Utah.
One of the most powerful myths about wolves is
that they commonly attack and eat people. A more recent "counter
myth" is that wolves pose no danger at all to humans. Neither
of these myths is correct. The idea that wolves hunt and kill humans
is quite old, and goes much farther back than the story of Little
Red Riding Hood. There are also numerous tales of wolves killing
people in pre-20th century
Europe. Despite these tales, a review of published studies on wolf
attacks clearly demonstrates that while wolves do sometimes attack
humans, such attacks are extremely rare. In fact, many of the recorded
attacks in Europe are now thought to be the work of hybrids between
wolves and domestic dogs. While it is always wise to treat wild
animals as potentially dangerous, there is little reason to fear
wolves in particular. As Linnell et al. (2002) put it: "When
the frequency of wolf attacks on people is compared to that from
other large carnivores or wildlife in general it is obvious that
wolves are among the least dangerous species for their size." Following is a summary
of some recent studies of wolf attacks: A recent European study
of historical and present-day records of wolf attacks (Linnell et
al. 2002) identified four factors that are associated with wolf
attacks on humans: 1) Rabies: Linnell et al. (2002) found that the vast majority of past
wolf attacks in Europe involved rabid wolves. As the incidence of
rabies has declined in Europe and North America, the frequency of
these attacks has dropped dramatically on these continents. However,
such attacks still occur in Asia and the Middle East. 2) Habituation. Habituated wolves are wolves that are “used”
to being around people, often because they are being fed by people.
Habituation is also blamed for most of the 18 recorded wolf “attacks”
(including very aggressive behavior) on humans (none of them fatal)
in North America since 1969 (McNay 2002). Similarly, Carnes and
Van Ballenberghe (2002) found that in the solid majority of documented
cases in 20th century North America where presumably
healthy wild wolves inflicted injuries (mostly minor) on humans,
habituation, likely as a result of feeding, was the common factor. 3) Provocation. This includes situations where someone is trying to kill
a trapped or cornered animal. 4) Highly modified
environments. The majority of “predatory” attacks (nearly
all of which have occurred in pre-20th century Europe,
or present day India) are associated with very artificial environments.
India (a country with >1 billion citizens), where a number of
fatal wolf attacks have been reported over recent decades, is often
cited as proof that wolves do attack and kill people. However, a
recent study found that such attacks occurred exclusively in highly
modified environments with high densities of both people and wolves
and low densities of wild game (Jhala 2000). He concluded that, given the substantial and constant degree
of contact between wolves and people in these areas, the likelihood
of an attack was still extremely low. Furthermore, a recent genetic
study suggests that that the Indian wolf (Canis lupus pallipes) is not a true “gray wolf,” but is in fact a
distinct subspecies that may be more closely related to the jackal
than to gray wolves (Aggarwal et al.
2003). This is extremely important, because the vast majority of
wolf attacks on humans in the 20th century, and nearly
all-fatal attacks, have been attributed to the Indian wolf. A recent incident in
which a wolf attacked a kayaker in his campsite near Vancouver Island
is commonly cited as more proof that wolves are inherently aggressive
and dangerous. Importantly, this incident is believed to be the
first reported wolf attack in British Columbia’s history (British
Columbia has thousands of wolves). Furthermore, according to the
locals in the Tofino area, the attack was neither an unexpected
nor an unpredicted incident. The seven resident Vargas Island wolves
had lost their ‘wild’ nature and became habituated or
tamed by human actions and increasing presence in the area. Residents
on the island have observed visitors feeding hot dogs to the wolves
by hand. Since the attack on Vargas Island, the BC government has
raised the fine for feeding wildlife to $300 (see: http://www.graywolf.ca/home.html).
Unprovoked attacks
by non-rabid wolves on people, then, are extremely rare. "The risks of being
attacked by a wolf are not zero," according to Linnell et al.
(2002) "But (they) are clearly so low they are virtually impossible
to quantify." Putting the Risk
Into Perspective: Forest Service e-mail reported 1992 figures on the
wildlife hazards afield. Topping the list of animal-caused human
deaths were auto collisions with deer, racking up 131 for the year
(to put things in perspective, sharks took only one human, bees
43, and rattlesnakes ten for that same year)
From 1989-94 there were 109 fatal dog attacks in the U.S In the next year, you have a 1 in 2 million chance of being killed by an animal. Wolves' Effect on Big Game Population
Another myth commonly associated with wolf reintroduction is that they always have a detrimental effect on big game populations. The reintroduction of 31 wolves in Yellowstone National Park (YNP) in 1995-96 has provided the opportunity to study the wolf-prey relationship in depth. However, any conclusions regarding the effects of wolf predation on prey species in YNP need to consider the varying environmental factors at work, including regional climatic conditions, other carnivore species in the region, and human harvest – all of which influence prey population dynamics (Smith et al. 2002). With this in mind, it is worth noting that Yellowstone is home to other predators such as grizzly bears, coyotes, and cougars that compete for the main sources of prey, such as elk, deer, moose, bighorn sheep, and beaver. Hunters also take hundreds of elk, deer, and bison as they migrate out of the park boundaries in search of food each year. The winter of 1996 was one of the severest on record in YNP. All these factors must be included when evaluating the effects of wolves on big game populations in YNP. The primary prey of the Yellowstone wolves is elk. The Park Service has determined that prior to the wolf introduction, the winter mortality of most ungulates (ungulates are large hoofed mammals like elk, deer, moose, bison, pronghorn and bighorn sheep) in the park was due to malnutrition (www.npwrc.usgs.gov/resources/2002/severity/intro.htm). The ungulate population prior to wolf reintroduction was at or near carrying capacity (Smith et al 2002). The Yellowstone elk herd was estimated at 17,290 in December 1994 (www.nps.gov/yell/nature/northernrange/appendixb.htm), the season prior to wolf reintroduction. Yellowstone has not released population data since 1994, but unofficial spring counts in 1997 place the herd around 10,000. The decline in elk numbers is not directly related to wolf reintroduction. No population counts were conducted in 1995-1996 or 1996-1997 winters due to the severe winter conditions. Harsh weather conditions played a large part in the decline of the elk (and other ungulates) population. Numbers for the northern Yellowstone elk herd show an increase after the hard winter (11,736-14,538) and have proven stable through 2000 (Smith et al. 2002). Studies conducted by the Yellowstone Center for Resources demonstrate the type of kills wolves have been making on the elk herd: As
expected, elk are the primary prey for wolves in the park
year round, representing 92% of 1,582 wolf kills recorded
from 1995-2001. As elsewhere, wolf predation in winter
has been highly selective; calves represent about 43% of wolf-killed
elk, cows 36%, and bulls 21% (compared to the approximate
winter population proportion of 14% calves, 60% cows, and
23% bulls). The adult elk killed by wolves have
been very old, with a mean age of 14 years for wolf-killed
cow elk. Douglas Smith, director of the Yellowstone Wolf Project, goes on to say: Human
hunters outside the park kill female elk in their reproductive
prime, at an average age of 6 years.
Bull elk killed by wolves are taken primarily in winter
and average 5 years old, which is the same average age for
hunter-killed bull elk. Research conducted within the park boundaries (where hunting is not allowed) of Yellowstone National Park looked closely at effects the wolf may have on the big game populations. Researchers concluded that, “over-winter calf mortality, yearling mortality, and adult bull mortality all increase with higher elk population densities. Studies show that summer predation by grizzly bears, coyotes, black bears, and golden eagles takes an average of 32% of the northern range elk calves each year. Mountain lions prey upon elk, as do hunters north of the park (taking about 10% of the northern herd annually through the 1980s)” (Smith et al. 2002). Clearly, no specific predator prey relationship can be attributed to the presence of just one species Gray
wolves, eliminated from the park by the 1930s, are being restored,
but not because park managers think the wolves will "control"
the number of elk. Instead, 15 North American wolf experts
predicted that 100 wolves in Yellowstone would reduce the
elk by less than 20%, 10 years after reintroduction. Computer
modeling of population dynamics on the northern winter range
predicts that 75 wolves would kill 1,000 elk per winter, but
that elk would be able to maintain their populations under
this level of predation, and with only a slight decrease in
hunter harvest (Boyce 1993). Some hunters have asserted that wolves are the number-one predator of big game herds. This is not usually the case. In addition to studies conducted at the to the Yellowstone research which demonstrate otherwise, another relevant case to mention is the recovery of wolves in Minnesota. There are now more than 3,000 wolves in the state which prey primarily on deer. These wolves kill an estimated 40,000 deer each year in Minnesota. By comparison, all other predators kill 60,000 deer, cars cause a mortality of 15,000 deer, and hunters kill more than 200,000 deer each year. Since 1973, when wolves were protected under the ESA, the wolf population has climbed steadily in Minnesota. However, so has the deer population, and hunter harvest as well, which is now more than twice what it was in 1973 when wolf populations began to increase. The numbers clearly show that it is hunters that have become the number one predator of big game herds. A serious discussion about the wolf predation on big game populations means sifting through the hyperbole surrounding this issue. In most of these cases wolves have been the least of the threats to these populations. The gravest threat to the vitality of big game populations comes from humans. Habitat degradation due to a variety of anthropogenic causes as well as habitat loss due to development is the primary causes of a decreased big game population. The large ungulate hunts in Utah also do not help the health of the herds. In contrast to wolves, hunters target productive females and bulls in their kills. It could be argued that this non-natural selection can contribute to a reduction in the big game populations in the long-term, along with habitat loss and competition with livestock for forage.
Much like the myth of wolf predation on big game populations, the issue of livestock losses needs to be examined more closely to discover the multitude of pressures livestock face. It cannot be denied that wolves have preyed on livestock and will continue to do so. However, it is important to put the numbers into perspective to fully understand the impact wolves have on livestock populations. Overall, wolf predation on livestock in the U.S. has been remarkably low, although there is no doubt that some ranchers are hit harder than others. The current ratio of wolf kills to known livestock deaths for the Northern Rockies 3-state recovery area, (Idaho, Montana, Wyoming): is (Bangs 2002):
These numbers do not justify the current rhetoric that wolves “decimate livestock herds.” Evidence shows that most livestock loss is the result of weather conditions and illness, not predation. And besides, in the event that wolf depredation of livestock can be confirmed, ranchers are eligible for compensation. The states, the federal government, and Defenders of Wildlife all have programs to compensate producers for the loss of livestock to wolves. In the case of the 3-state recovery area total compensation payments from Defenders of Wildlife from 1987-2002 totaled $272,000 dollars. There
are wolf packs in North America surrounded by ranching
and grazing lands but, interestingly, wolves do not normally
molest or kill the livestock around them.
For example, wolves have lived on the Agassiz National
Wildlife Refuge in northwest Minnesota since the 1980's
and are entirely surrounded by farmland. The perceived
threat of these wolves to livestock prompted research
on their habits in the late 1990's.
In this study, 17 wolves were caught, radio collared
and studied for 17 months around the clock (Gese 2003).
The wolves were found to make forays from the reserve
throughout the year into the farmland. Moreover, the wolves
on their treks frequently passed several groups of livestock
without molesting them. The wolves fed on wild prey, mainly
moose, white-tailed deer and muskrats. Wolves in the area
did occasionally kill livestock, but on average only once
a year. Gese
(2003) concluded that the risk to livestock in Agassiz
and surrounds is minimal.
Ironically, before the study, it was thought best
to destroy wolves that left the Refuge to avoid wolf-livestock
friction. In light of the findings, however, the wolves
would best be left in place, for at least they keep out
other wolves who might be less “neighbourly”
to livestock.
*source=www.wolftrust.org
** same 8 states featured in Table 1
So, what are the chief livestock killers, if not predators? * disease - particularly digestive, respiratory and birth problems Understanding the leading causes of livestock loss is an important facet in the discussion of wolf depredation. Too often, the wolf becomes the easiest target to identify as the culprit. As with big game populations, livestock are vulnerable to many other predators. The numbers reflect that the largest threat to livestock is disease and severe weather. A thoughtful comparison of these facts clearly demonstrates the insubstantial threat wolves pose to livestock. In addition to compensation programs, the issue of wolves and livestock has another component that sets it apart from the other myths. Unlike the other situations, there are steps that can be taken to reduce the number of livestock depredations. Over the years a variety of techniques have been used to minimize livestock loses (Cluff and Murray 1995). These techniques diverge in terms of effectiveness and humaneness. Remember that a particular effort to decrease livestock loses due to wolf depredation is not always applicable in every situation, and therefore an effective method for avoiding depredation will need to be an approach that integrates many different methods (Fritts et al. 1992). The methods that are most easy and most humane are: Putting the Cost of Depredation Into Perspective: There
are direct and indirect costs of livestock depredation by wolves
that should be accounted for when considering the economic cost
of wolf recovery. According to the USDA, annual agricultural losses
due to white-tailed deer exceed $500 million PER YEAR nationwide.
Losses due to birds are over $100 million and losses of livestock
to coyotes cost $41 million per year. In the Southeast, it is estimated
that beavers cause $100 million in economic damages every year.
In Pennsylvania alone, it's estimated that white-tailed deer cause
$30 million in lost agricultural production each year. In addition,
the 750,000 annual auto collisions with deer cause an estimated
$1.2 BILLION dollars in damages, 200 deaths, and 9,000 injuries
nationwide. Deer cause an estimated $250 million in damages to homeowners
in large metropolitan areas alone, not to mention 12,000 to 14,000
cases of Lyme disease. And so on. The point is that many wildlife
species cause economic damage. Wolves alone cannot be blamed for
causing the most substantial costs.
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