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The North American Wildlife
and Natural Resource s Conference held its 72nd meeting in March,
2007 in Portland, Oregon. This conference brings together
wildlife biologists and state wildlife agencies for discussion of wildlife
related problems. Session five of the Conference had nine symposiums just on
predator control. Below are a few excerpts from that Conference.
Culling Mountain Lions to Protect Ungulate Populations-Some
Lives Are More Sacred Than Others
Eric M. Rominger
New Mexico Department of Game and Fish
Bounties and Bounty
Hunters
Historically, top carnivore removal
was carried out to protect game species and livestock throughout the western
states. In fact, most predator species were bountied, with higher bounties paid
for culling females in a concerted effort to reduce or eliminate populations.
For example, in New Mexico in the 1950's, the
New Mexico Department of Game and Fish
employed full-time trappers in New Mexico as well (A. Ford, personal
communications 2003). This intensive governmental effort occurred during an era
when most private ranchers kept their
"steel in the ground", i.e., leghold traps, year-round in an effort to
eliminate top carnivores. It is important to note that these government
trappers were highly respected members of their communities and were considered
members of an honored profession. However by the early 1970s, all but two
western states had converted mountain lions to game-animal status and
state-agency trapper positions were essentially eliminated. Despite the best
effort of the government trappers and of their private-sector allies, mountain
lions were never extirpated in the western United States.
California versus Texas
California and Texas, bounding the western and eastern
distribution of mountain lions, have equally dichotomous management
strategies
for mountain lions. Presumably, these divergent management strategies
are based
on differing societal values in these two states. Texas never elevated
mountain lions to
game-animal status, and year-round hunting and trapping of mountain
lions
continues throughout their range there. The management strategy in
Texas contrasts sharply with that in California where a legislative
moratorium
passed in 1972 ceased sport harvest and public trapping of all mountain
lions.
Intensive
mountain lion harvest in Texas has not resulted in the extirpation of mountain lions,
and mountain lion distribution is considered to be similar today to what it was
35 years ago (C. Brewer, personal communication, 2007). Because of this fact,
Texas Parks and Wildlife (TPW) was a principal complainant resulting in the
Western Association of Fish and Wildlife Agencies (WAFWA) not endorsing, or
otherwise sanctioning, the recently drafted Cougar Management Guidelines-First Edition (Schroufe
2006). Perceived differences on the needs for harvest quotas and sanctuaries,
to maintain mountain lion populations, were central to this complaint.
The
consequences of no-sport harvest of mountain lions are less understood in California. High levels
of mountain lion predation on small isolated populations of bighorn sheep (Ovis Canadensis cremnobates) and Sierra Nevada bighorn sheep (O. v. sierra) populations being listed as federally endangered
populations.
Ballot Initiatives
It
is interesting that prior to the elimination of sport hunting in California, annual
harvest was approximately 150 mountain lions per year. Today, California and U.
S. Department of Agriculture, Wildlife Services cull approximately 150 mountain
lions per year because of depredation complaints on livestock and on pets and
because of concerns for human safety. The historical number of 150 mountain
lions per year more accurately reflects the actual number of mountain lions
killed than does the current estimates because a bounty was paid during much of
the historical period. It has been suggested that frustration with restrictions
imposed by Proposition 117 may result in mountain lions being killed illegally,
resulting in an underestimate of mountain lion harvest. Total mountain lion
harvest in California
today, following the complete ban of sport harvest, probably exceeds mountain
lion harvest prior to the ban.
Endangered Ungulates
versus Hunted Ungulates
In
New Mexico,
state-endangered desert bighorn sheep declined to fewer than 170 individuals
with mountain lion predation determined to be the principal mortality factor
(Rominger and Weisenberger 1999, Rominger et al. 2004).
Mortality
data (Rominger et al. 2004) combined the evidence in New Mexico of the subsidized predator
prediction, resulted in near unanimity among concerned groups and agencies that
culling mountain lions to mitigate the high level of mortality was required to
avoid extinction of this state-endangered species.
Between
1985 and 1999, mountain lions were not culled to protect endangered desert
bighorn sheep in New Mexico
(New Mexico Department of Game and Fish, personal communication 2007). Between
1992 and 1999, approximately 85 percent of the known-cause mortality of
radiocollared desert bighorn sheep was attributed to mountain lion predation
(Rominger et al. 2004). Concern about the cascading effects of a subsidized
mountain lion population on the faunal biodiversity in the New Mexico portion of the Chihuahuan desert,
particularly state-endangered desert bighorn sheep, resulted in an agency
decision to reinstitute culling of mountain lions in five desert bighorn sheep
ranges. A combination of translocation and significantly higher survival rates
of radiocollared adults has resulted in
the desert bighorn sheep population in New Mexico increasing from fewer than
170 in 2001 to more than 400 in 2007 (New Mexico Department of Game and Fish, personal
communication 2007).
Conclusions
The
geographic range of mountain lions is larger than any big-game mammal in North
and South America (Logan and Sweanor 1999).
A
better understanding of the cascading effects of subsidized mountain lion
populations and the effects of harvest regimes on mountain lion populations,
may change both societal perspectives and perspectives of management agencies
responsible for these populations. It is important for society, and for
scientists, to recognize that societal perspectives and scientific understanding
change with time and with increased knowledge.
Role of State Wildlife
Agencies in Managing Mountain Lions
Terry M. Mansfield
Idaho Department of Fish
and Game
Boise, Idaho
Introduction
Mountain
lions (Puma concolor) are the most
widely distributed obligate carnivore in North America.
The species' range generally overlaps that of their primary prey, mule and
white-tailed deer (Odocoileus sp.)
yet they also rely on a wide range of large and small mammals as alternate
prey. Historically, mountain lions occupied diverse habitats throughout much of
the United States.
Intensive predator-control programs, intended to protect livestock and to
restore big-game populations during 1900 to 1965 significantly reduced
populations over much of the range. And, mountain lions were extirpated from
large areas of the Midwest and eastern regions
of the country. In general, populations now appear to be stable to increasing
throughout most of the western United
States; although densities are not uniform.
There is evidence of mountain lions recently recolonizing areas in the Midwest and in eastern regions of the country.
The
history of mountain lion management in the United States reflects extreme
shifts in public policy and in state wildlife agency management programs over
the last 100 years. Although reliable estimates of distribution and abundance
are not available prior to the 1970s for most states, it is likely that both
the distribution and abundance of
mountain lions were reduced and suppressed between 1900 and 1965. This trend
resulted primarily from intense efforts by state and federal agencies to
protect livestock and to aid in the recovery of native ungulates based on their
value to hunters. Liberal hunting seasons and methods of take, incentives to
hunters in the form of bounties, and employment of government hunters were
widely used to reduce mountain lion numbers in much of the western United States
until the 1960s.
The
practice of employing government lion hunters generally ended in the 1950s, and
state-sponsored bounty payments for killing lions, common in the West from 1910
to 1960, ended in the early 1970s.
In
the case of mountain lions, the states have authority over their management,
with the exception of the Florida
panther (Puma concolor coreyi) which
is listed under the Federal Endangered Species Act.
There
are also public concerns related to threats mountain lions may pose to public
safety. In California,
where there have been 11 verified mountain lion attacks on humans since 1985, 3
of which resulted in death of the victims, the state wildlife agency has been
forced to devote considerable staff time and funds to developing and
implementing emergency response capabilities (S.Torres, personal communication
2006). The real and perceived threats to public safety cannot be ignored by
state wildlife agencies, regardless of relative risk, since they directly
influence mountain lion management policy and most agencies have a public
safety related mandate.
Legal Status of Mountain
Lions in the West
The
individual states have responsibility for managing mountain lions on behalf of
the people, and the wildlife agencies are generally the custodians for all
wildlife within each state. However, the specific legal status of mountain
lions is defined in the laws for each state. In addition, commissions or
administrative wildlife agencies generally have authority to adopt management
plans, policies and regulations to implement, interpret and make specific state
laws, including hunting seasons, limits and methods of take.
By
1975, western states had terminated bounties and had designated mountain lions
as either big-game or trophy-game species. In a number of states over the last
30 years, sociopolitical processes forced wildlife agencies to study the
mountain lion populations, to report on findings and to recommend conservation
and management methods to policy makers.
Science-based Management
to Achieve Goals and Objectives
So
what is the appropriate role of the state wildlife agency in managing mountain
lions based on science?
In
California,
emphasis is placed on protecting important habitat, on responding to public
safety incidents and on improving public awareness of mountain lions as the
state wildlife agency tries to deal with the pressures caused by a human population
of over 35 million. By contrast, in Idaho
with a human population of less than 1.5 million, there is more emphasis placed
on providing diverse hunting opportunities and on managing mountain lions in
conjunction with prey species, including bighorn sheep, deer and elk.
Public
policy goals for mountain lion management can either assist or hinder the state
wildlife agency in implementing science-based management of the species. If the
policies provide a strong mission statement for the agency, if the agency has a
well qualified professional staff and if adequate funding is provided, the
environment for science-based adaptive management is enhanced. However, if a
state's public-policy goals for mountain lion management are not clear, if it
lacks well qualified professional staff or if it lacks adequate funding to
implement a balanced program, effective science-based management of mountain
lions cannot be expected.
Management in Response
to State Holder Values
In
general, state wildlife agencies respond to public input and stakeholder values
regarding wildlife, including mountain lions. Stakeholder values are generally
reflected in the state's laws and policies regarding mountain lion management,
het they may not represent the full range of current public values as human
demographics are changing rapidly in the western states. There may also be lag
time in public values translating to laws and policies through the normal
legislative and commission processes. This delay can also result from the
influence of special-interest stakeholders and political pressure to resist
change.
Summary
The
role of state wildlife agencies in managing mountain lions involves a
combination of factors unique to each state, including laws, policies, an
agency's mission and stakeholder values. Recently, a working group published Cougar Management Guidelines (Guidelines;
Beck et al. 2005) in an effort to synthesize and organize available information
on management of the species. Although the western state wildlife agencies recognize
that these Guidelines contain useful information, the process used to develop
them and the final product raised concerns related, primarily, to failure of
the authors to incorporate agency recommendations for changes to the draft
document they were asked to review.
At
the end of the day, the ultimate responsibility for managing mountain lions
rests with the individual state wildlife agencies. The challenge facing each
agency is how best to adaptively implement science-based management while
maintaining viable populations in conjunction with prey species and responding
to stakeholder demands for sustainable hunting opportunities and minimizing
conflicts with humans involving livestock damage and public safety.
Managing Predator-Prey
Systems: Summary Discussion
Mark S. Boyce
University of Alberta
Edmonton, Alberta
Robert L. Byrne
Safari
Club International Foundation
Washington, D.C.
Introduction
Many
studies have demonstrated population consequences of predators on prey
populations, but how managers should use this information is not easy to
decide. Predator control can be effective at enhancing survival and recruitment
in populations of prey, but certain methods for controlling predators sometimes
meet with fierce resistance from the public.
Conflict with predators
Public
reaction is often intense when predators kill pets, and cougar and wolf
predation on dogs is relatively common and apparently increasing (Treves et al.
2002; Beck et al. 2005) Likewise, humans themselves are occasionally killed by
large carnivores, triggering fear and resentment towards offending animals
(Packer and Kissui 2007).
With
expansion of cougar and wolf populations in North America
during the past decade, wildlife managers are faced with a new dimension in
trying to manage big game populations in the face of predation levels that did
not exist in previous decades.
Conclusions
Keeping wolf and cougar populations in check
might require reducing alternate prey (Gibson 2006; Wielgus 2007). Control of
abundant mule deer populations in the Sierra Nevada mountains of California might be required in addition to reductions in
cougar numbers to prevent extirpation of Sierra Nevada
bighorn sheep populations (Gibson 2006).
We
believe that wildlife managers have not fully taken advantage of the
opportunity to involve hunters and trappers in harvesting predators, and we
need to understand how to use these people more effectively in predator
management (Hammill 2007). Even though large numbers of predators are taken by
hunters and trappers, they often are not very effective at achieving predator
control (Zager et al. 2007) because predators are not removed from populations
where predator control is most needed.
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