Wolf reintroduction to Scotland: public attitudes
and consequences for red deer management
Erlend B. Nilsen1,2,*, E. J. Milner-Gulland3, Lee Schofield4, Atle Mysterud1,
Nils Chr. Stenseth1and Tim Coulson3
1Centre for Ecological and Evolutionary Synthesis (CEES), Department of Biology, University of Oslo,
PO Box 1066 Blindern, 0316 Oslo, Norway
2Department of Forestry and Wildlife Management, Hedmark University College, 2480 Koppang, Norway
3Division of Biology and Centre for Population Biology, Imperial College London, Silwood Park,
Ascot, Berks SL5 7PY, UK
4Centre for Environmental Policy, Imperial College London, Exhibition Road, London SW7 2PY, UK
Reintroductions are important tools for the conservation of individual species, but recently more attention
has been paid to the restoration of ecosystem function, and to the importance of carrying out a full risk
assessment prior to any reintroduction programme. In much of the Highlands of Scotland, wolves (Canis
lupus) were eradicated by 1769, but there are currently proposals for them to be reintroduced. Their main
wild prey if reintroduced would be red deer (Cervus elaphus). Red deer are themselves a contentious
carrying capacity, and are believed to have a considerable economic and ecological impact. High deer
densities hamper attempts to reforest, reduce bird densities and compete with livestock for grazing. Here,
we examine the probable consequences for the red deer population of reintroducing wolves into the
Scottish Highlands using a structured Markov predator–prey model. Our simulations suggest that
reintroducing wolves islikely togenerate conservation benefits bylowering deer densities. Itwouldalso free
deer estates from the financial burden of costly hind culls, which are required in order to achieve the Deer
costs, particularly through increased livestock mortality. We investigated perceptions of the costs and
benefits of wolf reintroductions among rural and urban communities in Scotland and found that the public
are generally positive to the idea. Farmers hold more negative attitudes, but far less negative than the
organizations that represent them.
Keywords: Markov model; predator–prey dynamics; trophy harvest; wildlife economics
Large predators have been extirpated from much of their
historical range (e.g. Mech 1995). This has resulted in
elevated densities of large herbivores in areas where
human hunting has not replaced natural predation in
limiting population growth (see e.g. Gordon et al. 2004).
Such high herbivore densities are sometimes considered
detrimental to the environment as they may hamper
attempts to reforest (Putman & Moore 1998), reduce
bird densities (Fuller & Gough 1999) and compete with
livestock for grazing (Clutton-Brock & Albon 1989). One
suggested route to reducing deer densities is to
reintroduce large carnivores (Wilson 2004). Indeed,
reintroduction programmes have received an increasing
amount of attention over the last decade (Carroll et al.
2003). The aim of such programmes has usually been
simply to preserve the species being reintroduced.
However, it is also important to consider whether the
species’ ecosystem function can also be restored (Soule ´
et al. 2003). As reintroductions have wide-ranging
implications (Soule ´ et al. 2003), it is important that a
proper assessment of the ecological implications is
carried out in advance. Furthermore, the success of the
programme will be strongly influenced by the opinions of
local people (Fritts et al. 1997)
In much of the Highlands of Scotland, red deer (Cervus
elaphus) densities are currently thought to be close to the
food-limited carrying capacity (Clutton-Brock et al.
2004). Red deer populations at current densities are
widely considered to impact negatively on the environ-
ment due to overgrazing (Hester 1996). However, the deer
population in Scotland is difficult to control by hunting, as
there is little economic demand for hunting. Instead,
managers cull deer in order to control their densities, with
the Deer Commission for Scotland having a stated
management objective of six deer per square kilometre.
This culling of hinds is accompanied by trophy hunting for
stags, but the operation barely breaks even overall
(Milner-Gulland et al. 2004). Owing to this failure to
control deer numbers (Clutton-Brock et al. 2004), the
interaction between deer and land management has
become a controversial issue within the UK. One
solution to reducing deer numbers that has been discussed
is the reintroduction of red deer predators—particularly
grey wolves (Canis lupus)—into the Highlands. Wolf
Proc. R. Soc. B (2007) 274, 995–1002
Published online 30 January 2007
Electronic supplementary material is available at http://dx.doi.org/10.
1098/rspb.2006.0369 or via http://www.journals.royalsoc.ac.uk.
*Author for correspondence (email@example.com).
Received 6 December 2006
Accepted 21 December 2006
This journal is q 2007 The Royal Society
reintroduction into the Highlands is currently a conten-
tious issue within the UK, with opponents and supporters
holding strong views.
In this paper, we attempt to provide an unbiased
quantitative insight into two aspects of the possible
consequences of a wolf reintroduction. First, we
developed a simulation model to assess the expected
effects of wolf reintroduction on the population dynamics
of Highland red deer. Transient dynamics, equilibrium
densities and the implications for deer hunting were
examined. Livestock depredation was not included in the
model, but the issue is considered in the discussion. We
then carried out a survey of the attitudes of people living in
rural Scotland, in an area where wolf reintroduction has
been proposed, and of urban residents, and compared the
results with attitudes expressed by the media and the
2. MATERIAL AND METHODS
(a) Population modelling
The dynamics of the red deer population were described
using a density-dependent, discrete-time, age- and sex-
structured Markov model. The deer population model was
parameterized from the long-term individual-based study
conducted in the North Block of the Isle of Rum, Scotland
(e.g. Clutton-Brock et al. 2002). A complete description of
the red deer population model can be found in Clutton-Brock
et al. (2002), Milner-Gulland et al. (2004) and as electronic
supplementary material to this paper.The model captures the
dynamics of population growth on theisland of Rum very well
and is an acceptable base model for red deer in the Highlands
of Scotland more generally (Clutton-Brock et al. 2002;
Milner-Gulland et al. 2004).
We simulated the wolf population using an individual-
based model. Our model was a variant of the models used by
Haight et al. (1998) and Chapron et al. (2003), but was
updated with respect to the interactions between the wolves
and their prey. As previous studies have shown that the social
organization of wolves strongly influences their population
dynamics and extinction probabilities (Vucetich et al. 1997;
Haight et al. 1998), a detailed approach is necessary to
capture the dynamics. The model distinguished individuals
by their membership of a wolf pack, which consisted of a
dominant breeding pair and one or more cohorts of their
offspring (see also Haight et al. 1998). The dominant female
in each pack bred yearly, producing a single litter. By their
first winter, the pups were fully grown. We also incorporated
an annual rate of dispersal from the natal pack. A dispersing
wolf might then colonize a vacant territory or join a widowed
alpha individual of the opposite sex and become a dominant
individual. A full description of the modelling philosophy is
found in the electronic supplementary material.
As demographic stochasticity is known to affect the
population dynamics of small populations, each transition
was modelled as a binomial probability. Consequently, the
fate of each wolf was determined by drawing a random
number (between 0 and 1) and comparing it with the
probability that a certain event occurred (e.g. mortality,
For simplicity, we assumed that prey kill rates were
depressed at low deer densities and were more affected by
stochastic factors (e.g. snow conditions; Post et al. 1999) at
moderate-to-high densities. We consequently chose a type II
functional response represented by the disc equation
where k is the per capita kill rate (deer killed per wolf per year);
P is the deer density; a is the asymptote which the kill rate
approaches and h the deer density at which the kill rate
reaches half the asymptotic value. By setting h low (0.5 deer
kmK2), kill rates are relatively constant across a wide range of
deer densities, as observed in data from Yellowstone area
(Smith et al. 2004) and in comparisons across studies
(Eberhardt et al. 2003). To account for stochastic variation
in the kill rate (Post et al. 1999; Hebblewhite 2005), we
modified the realized kill rates such that (equation (2.2))
where k0is the realized per capita kill rate and 3 is a Gaussian
distributed random variable with mean zero and sZ0.05.
The total number of deer killed by wolves is a function of the
number of wolves present and the per capita kill rate.
Furthermore, we accounted for the fact that wolves prefer
to kill certain age classes by adopting and modifying the
approach taken by Fieberg & Jenkins (2005). Thus, wolf-
killed deer were distributed among the different age and sex
classes by the following formulation (equation (2.3))
where k0is the realized per capita kill rate; ki,jis the number of
individuals from sex i and age j that are killed per wolf per
year; ni,jis the number of individuals in sex i and age class j;
and Seli,j is the selectivity constant for sex i and age j
individuals (Fieberg & Jenkins 2005). We assumed that the
wolves selected juveniles and old females (10 years or more;
Smith et al. 2004), with the selectivity constant given by Sel1,
which is relative to the selectivity constant for all other age–
sex categories (Sel2).
To account for the effect of prey availability on wolf
population growth, we assumed that wolf survival was
affected by the deer : wolf ratio (equation (2.4))
where Si is the realized age-specific survival; si is the
maximum age-specific survival; g is the deer : wolf ratio at
which the survival is half of maximum; and P is the deer : wolf
ratio. Although the literature is very limited on whether vital
rates in wolves are density dependent or ratio dependent,
circumstantial evidence suggests that survival rates are lower
whenper capita prey availability is low(Fuller et al. 2003). We
assumed that the survival rates differed between juveniles
(sjuv), wolves aged 1–6 years (sprime) and older wolves (sold).
All parameter values are given in the electronic supple-
To predict the equilibrium numbers of deer and wolves for
different levels of hind culling rates, we simulated the
stochastic population model in 100 loops, each lasting 100
years (initial trials suggested that 100 time-steps were
sufficient to reach equilibrium). In each loop, we first ran
the deer model for 50 years without any harvesting or
predation to reach equilibrium. Then we released three wolf
996E. B. Nilsen et al.Wolf reintroduction to Scotland
Proc. R. Soc. B (2007)
packs into the system, each consisting of one dominant pair
and two subordinates. We scaled deer density to give the
number of deer 2000 kmK2, the approximate size of the area
considered by the ‘Trees for Life’ project (see below),
assuming that dynamics would be similar across the
25 000 km2Scottish Highlands if wolves were allowed to
colonize the entire area.
(b) Estimated economic consequences for deer estates
To investigate the potential economic consequences for the
deer estates, we assumed that the estates followed the
recommendations from Deer Commission for Scotland
aiming for approximately six deer kmK2. To reach this
management goal, a hind cull is needed in order to control
population growth. As the commercial harvest in Scotland is
mainly for trophy stags, we assumed £200 profit per stag and
£50 loss per hind (Milner-Gulland et al. 2004). We then
compared the economic outcome for the deer estates prior to
and after a wolf reintroduction by varying the harvesting rate
for trophy stags.
We did not model the economic consequences for the
sheep farming industry, but considered the broad impli-
cations of wolf reintroductions for farmers’ livelihoods.
(c) Sensitivity analysis
We used standardized linear regressions between parameter
values and model predictions to determine prediction
sensitivity to parameter values—see McCarthy et al. (1995)
Fieberg & Jenkins (2005) for a more general discussion. As
information about parameter uncertainty was scarce for most
parameters, we used uniform distributions (Fieberg & Jenkins
2005). We then drew 200 sets at random from these
distributions and ran the stochastic model 50 times for each
set of parameters. Each of the 50!200 simulations were run
for 100 time-steps, with population sizes reported for the final
time-step, such that sensitivities are reported for the
equilibrium only. We then calculated the mean equilibrium
deer population size across simulations for each set of
parameter values. Using mean population size at time tZ100
data scaled to have a mean of zero and a standard deviation of
unity (Saltelli et al. 2000). If parameters are not strongly
the square of the regression estimate for that parameter
(Saltelli et al. 2000). We looked for evidence of strongly
nonlinear sensitivities by fitting quadratic terms (b1xCb2x2)
inclusion of these terms. Note that this technique results in
unit-less coefficients representing the relative importance of
the different parameters (Fieberg & Jenkins 2005).
(d) Assessing rural and urban attitudes to wolf
The rural survey was carried out in the Glen Affric area of
Scotland. This area was chosen because it borders the area
the Scottish Highlands with the ultimate aim of rewilding the
area, including reintroduction of wolves and other recently
extirpated large mammals (http://www.treesforlife.org.uk/tfi.
acti.html). Consequently, this rural population is particularly
sensitized to issues regarding wolf reintroduction. We carried
out a geographically stratified random sample with hand-
delivered questionnaires, obtaining a 65% response rate
and 126 usable responses. The urban sampling was carried
out opportunistically at leisure centres and shopping centres in
Inverness and Edinburgh, producing a sample of 226
respondents. The attitude scores were calculated using a
5-point Likert scale of responses to nine attitudinal questions
of the resulting ordinal scale (Pate et al. 1996). The Factiva
search engine (http://www.factive.com) was used on 23 June
2005, searching UK local and national newspapers excluding
republished news, pricing and marketing data, obituaries and
sports news. A Boolean ‘OR’ search was done for ‘wolf or
wolves’ as free text in the headline and lead paragraph. Articles
were then individually screened for relevance and content
advantages and disadvantages of reintroduction in the ques-
tionnaire (Goulding & Roper 2002). Key informant interviews
for the organization as a whole.
(a) Population modelling
At the start of the simulation, red deer numbers were at
equilibrium, either hunted or unhunted depending on the
scenario under examination. Three wolf packs, each
consisting of one dominant pair and two subordinates,
were introduced into the system at time tZ1. After an
initial decrease in deer numbers and an increase in wolf
numbers, wolf numbers rapidly declined to a mean
equilibrium value of 25 wolves per 1000 km2(s.d.Z
17)—a value similar to those recorded in unmanaged wolf
populations in the Bialowieza Forest, Poland (20–49
wolves per 1000 km2; Jedrzejewski et al. 2002). An
equilibrium density of approximately seven deer kmK2
(s.d.Z3.2) was reached ca 60 years after the initial
release (figure 1). The deer : wolf ratio (approx. 288) is
time (years since reintroduction)
deer density km–2
wolf numbers (1000 km–2)
Figure 1. Predicted transient dynamics following the
introduction of wolves into Scotland. The dashed line
represents hind (3 years or more) densities, the dotted line
trophy stag (more than 5 years) densities, and the solid
line wolf densities. Standard deviations (thin dotted lines)
around the lines do not include cases when wolves went
extinct. The grey points are wolf densities in the northern
range of Yellowstone National Park following the wolf
reintroduction in 1995 (from Smith et al. 2003).
Wolf reintroduction to Scotland
E. B. Nilsen et al.
Proc. R. Soc. B (2007)
consistent with those reported by Fuller et al. (2003).
Initial conditions (deer density and number of wolf packs
released) affected the time needed to reach equilibrium
and the peak wolf population, but not equilibrium density.
Although the equilibrium reached was unaffected by
the initial conditions, the equilibrium deer numbers are
strongly dependent on hind culling rates (figure 2a). This
in turn affected the viability of the wolf population. When
we simulated the model without any deer harvesting, the
wolf population went extinct in ca 19% of the simulations.
With increasing hind culls, the probability that the wolf
population went extinct increased dramatically. In
general, the red deer population could not support a
harvest greater than 4–5% of females as well as a viable
wolf population (figure 2b). Our simulations thus suggest
that the viability of the wolf population is strongly
dependent on the prey density.
In our simulation, the deer and wolf populations
attained point equilibria, and there was no indication of
(autoregression coefficients (mean (5th and 95th percen-
tiles)): AR(1)-coef: 0.20 (K0.28–0.53), AR(2)-coef: 0.07
(K0.33–0.37)). There is a specific range of conditions
when cycles between predators and prey do not occur,
with the prey population growth rate and density
dependence on the prey population growth rate being
the important factors. We suspect that because most
female red deer in the Highlands only reproduce every
second year (Clutton-Brock & Coulson 2002), the growth
rate of the red deer population is not high enough to
(b) Estimated economic consequences for
Model results suggest that a wolf reintroduction would be
economically beneficial for deer estates through a
reduction in deer numbers and hence the removal of the
requirement to cull hinds in order to meet the Deer
Commission’s management objectives (figure 2c).
However, it would reduce the number of stags available
to hunters (figure 2a). If we assume £200 profit per stag
and £50 loss per hind, we estimate that in the presence of
wolves an estate would make £800 yrK110 kmK2from
culling 40% of stags and not hinds, while without wolves it
would make £550 yrK110 kmK2from culling 40% of stags
and 11% of hinds, the appropriate hind culling rate
required to meet management objectives (i.e. approx. 6
deer kmK2; see also Milner-Gulland et al. 2004). We have
not accounted for the possibility that trophies may
increase in size because deer would be at lower densities
in the presence of wolves, and thus that an individual
trophy may achieve higher returns.
stage harvest rate (%)
income (£ per year)
hind harvest rate (%)
hinds (before wolves)
stags (before wolves)
hinds (after wolves)
stags (after wolves)
hind harvest rate (%)
p(e) for the wolf population
wolf number (1000 km–2)
Figure 2. Ecological and economic consequences of wolf reintroduction. (a) Estimated trophy stag (5 years or more) and hind
(3 years or more) densities before and after wolf reintroduction for a given hind harvest, when stags are unharvested.
(b) Estimated wolf population density (solid line and open circles) and extinction probabilities for the wolf population (dotted
line and filled circles) at different hind culling rates. (c) Estimated annual revenue at equilibrium for a 10 000 ha estate from
culling trophy stags (5 years or more) when the income is set to £200 for a stag and K£50 for culling a hind, at different culling
rates for stags and an unmanaged wolf population. In the situation with no wolves, hinds are culled at approximately 11%, the
rate needed to keep the deer population at roughly six deer kmK2. In the situation with wolves, no hinds are culled.
998E. B. Nilsen et al. Wolf reintroduction to Scotland
Proc. R. Soc. B (2007)
(c) Sensitivity analyses
dependent primarily on the rate at which wolves kill deer
and the probability that a dispersing wolf is successful in
establishing a territory (psettle; table 1). The other
parameters in the wolf population model had a less strong
effect on the deer equilibrium numbers. Unfortunately,
all parameterswith large sensitivities have large confidence
intervals in the literature, so until further research
provides more accurate estimates we should interpret the
results in terms of the essential features of the predicted
dynamics rather than focusing on exact numbers.
(d) Assessing rural and urban attitudes to
Attitudes to reintroductions of wolves and other extirpated
components of the British fauna varied between rural and
urban samples. Urban respondents had a mean attitude
score of C5.3 on a scale of K18 to C18, while rural
respondents had a significantly lower score of C1.9
(figure 3). The lower score for the rural population was
due to the negative attitudes of the subsample of farmers
(mean score K4.7). When offered a choice of scenarios,
43% of respondents favoured the reintroduction of a range
of species, including wolves, into the wild; 35% favoured
reintroductions into fenced eco-parks; 8% favoured
reintroductions of species other than wolves (e.g. beavers)
and 14% favoured no reintroductions of any species. Of
the rural population, 23% felt that deer control was the
major advantage of wolf reintroductions, with the
potential for tourism ranking second (21% of respon-
dents). Of urban respondents, 19% felt that tourism
would be the major benefit, but they also saw a range of
other advantages that were not highlighted by the rural
community, including preserving Scotland’s heritage and
restoring the balance of nature. The major concern of the
rural population was loss of livestock (54% of respon-
dents), while the urban population was predominately
concerned about the potential of wolves to harm humans
(35% of respondents). The attitudes of people other than
farmers reflected media coverage of the wolfissue; a search
of UK national and local newspapers using Factiva
revealed that 54% of articles mentioning wolves had a
positive message and 19% were negative. The attitudes of
stakeholder organizations ranged from K16 (National
Farmer’s Union for Scotland) to C18 (Trees for Life),
with the Mammals Trust UK (C7) closely matching the
mean urban attitude, and the Scottish Countryside
Alliance (K4) being close in attitude to the farmer sample.
Deer management in Scotland is relatively unusual
compared to most countries where wolves exist. In both
North America and Scandinavia, there is a culture of deer
hunting for meat as well as for trophies (Milner et al.
2006), with a clear objective of maintaining deer
populations for human use. Our results suggest that it is
not viable to maintain anything other than a very low level
of hunting in the presence of an unmanaged wolf
population (see also Nilsen et al. 2005; White & Garrott
2005; Nelson & Mech 2006). Conversely, the UK’s focus
on stag hunting for trophies means that wolf introduction
could make deer estates more profitable by removing the
need to cull hinds to meet the Deer Commission for
Scotland’s management objectives. The potential lack of
conflict between hunters and wolves in the Highlands
makes Scotland a particularly interesting case study, as
disagreement between stakeholders has generated sub-
stantial controversy over carnivore reintroductions and
recolonizations in Scandinavia, France and the United
States (Ericsson & Heberlein 2003; Naughton-Treves
et al. 2003; White & Garrott 2005).
Our model apparently captures the dynamics of one
expanding wolf population well—the early recolonization
phase closely followed the observed patterns in the
northern range in Yellowstone National Park (figure 1;
see Smith et al. (2003) for numbers from Yellowstone),
although the peak density reported here is higher. Other
reintroduced or recolonizing wolf populations, however,
have experienced long lag phases at low numbers, the
reasons for which are sometimes clear and sometimes less
obvious (Wabakken et al. 2001; Boitani 2003). This result
is not particularly surprising, as populations are often
limited by life-history and stochastic events during the
initial stage of population expansion. In our model, the
viability of the wolf population was also highly dependent
on the prey base, further highlighting the dichotomy in
outcomes, which is also reported in the literature (see also
Vucetich et al. 1997).
Table 1. Sensitivity analysis of the equilibrium population size of deer to parameters in the wolf model. (The first three
parameters relate to wolf predation on deer and the remaining parameters to wolf demography. We report sensitivities of
parameters of the wolf model only because the sensitivities of red deer population size to model parameters have been reported
elsewhere (Milner-Gulland et al. 2004). Sensitivities were estimated using standardized linear regression of model results
obtained by extensive parameter perturbation.)
description of parameterparameter name
asymptotic kill rate (deer/wolf)
deer density at ½a
selectivity constant of juveniles and old females
(10 years or more)
deer : wolf ratio when adult wolf survival
Zone-half maximum value
probability that a dispersing wolf settles
Wolf reintroduction to Scotland
E. B. Nilsen et al.
Proc. R. Soc. B (2007)
Compared with current deer densities in the High-
lands, our simulations suggest that the deer density in
some areas will be reduced by more than 50% following a
wolf reintroduction, even in the absence of any excessive
hind cull. Is it probable that a wolf reintroduction in the
Scottish Highlandswill have such a dramatic effect on deer
densities? Empirical evidence suggests that wolves often
affect deer population dynamics lowering overall popu-
lation density (Hebblewhite et al. 2002; Jedrzejewski et al.
2002; Nelson & Mech 2006). However, in an extensive
review of the literature on predation control, Ballard et al.
(2001) found that only a limited set of studies reported a
clear effect of predator removal on deer densities and
surplus available for human exploitation, mainly because
the wolves predominantly killed old and sick individuals.
However, most of these studies concerned white-tailed
deer (Odocoileus virginianus) and mule deer (Odocoileus
hemionus) that often twin every year and thus reproduce at
a much higher rate than the Scottish red deer which can
produce a maximum of a single calf every other year.
We may therefore expect wolves to have a greater effect
due to the lower reproductive rate of the prey species.
This is really a question about whether communities
are structured by top-down or bottom-up processes
(Sinclair & Krebs 2002). Most studies indicate that
both processes are likely to act simultaneously to
various degrees (McLaren & Peterson 1994; Testa 2004;
Vucetich & Peterson 2004). On Isle Royale, while wolves
do indeed affect the population dynamics of moose (Alces
alces), climatic factors such as snow conditions are moving
the system between periods of top-down and bottom-up
control (Vucetich & Peterson 2004). Hence, the degree to
which wolves affect deer density is determined by a range
of factors which are difficult to quantify a priori,
but given our current understanding, our model results
Wolves are likely to spread from their area of initial
release throughout the Highlands and this will impact on
wildlife other than deer. Many impacts are likely to be
positive; the presence of wolves may reduce predator
control costs on grouse moors through intra-guild
interactions (Palomares & Caro 1999), and reduced deer
densities may lead to increased rates of natural forest
regeneration, lower densities of deer ticks that spread
Lyme disease (but see Perkins et al. 2006) and potentially
elevated breeding success of some passerine species
(Fuller & Gough 1999). The reintroduction of wolves
into the greater Yellowstone area has also shed some light
on this important issue. Ten years after the reintroduction,
several studies have reported effects on prey abundance
(White & Garrott 2005; but see also Vucetich et al. (2005)
for an opposing result), carrion availability for scavengers
(Wilmers & Getz 2004) and regeneration of cottonwood
and Salvia spp. (Ripple & Beschta 2003). Again, the
evidence suggests that wider ecosystem-level effects are
likely to occur but are difficult to quantify a priori.
Wolf predation on sheep will cause conflict. Our model
does not consider the impact of wolves on sheep. This is
for two reasons: first, a one prey–one predator model has
substantially fewer parameters than a two prey–one
predator model, especially if the prey interacts through a
shared food resource as is the case with sheep and deer in
Scotland. Given the existing parameter uncertainty,
including sheep would substantially weaken model
predictions. Second, the dynamics of the Scottish sheep
farming industry are currently changing rapidly, making it
difficult to parameterize this part of the model. In the
Highlands of Spain, where sheep roam freely as much as
they do in Scotland, wolf predation is responsible for 80%
of natural sheep mortality (Blanco 2000). If, as it seems
probable, wolf predation on sheep in Scotland were at a
similar level, it would reduce flock sizes. So, why are sheep
farmers not more strongly opposed to wolf reintroduction?
Part of the reason may be that, on average, little or no
profit is made directly from sheep by Highland farmers—
profits accrue through subsidies. For example, the average
profit per sheep farm in the Highlands in 1999–2000 was
£24 300, of which £24 500 was through subsidies
(SEERAD 2001). In other words, without subsidies, the
average sheep farm made an operating loss. If farmers are
given economic compensation for wolf-killed sheep, the
conflict potential need not be too high. Traditionally,
farmers have been paid per sheep, although EU policy is
now changing towards paying farmers for maintaining
grazing irrespective of flock sizes. Such a policy is likely to
facilitate the reintroduction of wolves. However, the
tolerance of wolves is not always related to economic
compensation (Naughton-Treves et al. 2003), and the
emotional consequences to sheep farmers experiencing
wolf predation should not be ignored. Furthermore, wolf
predation on sheep would be controversial from an ethical
and animal rights perspective, and disagreement could
arise between stakeholders wishing to reduce sheep
–18 –16 –14 –12 –10 –8 –6 –4 –2 0 +2 +4 +6 +8 +10 +12 +14 +16 +18
SCA NFUSNTS MTUKSWT TfL
Figure 3. Attitudes of stakeholders to the reintroduction of wolves into the Scottish Highlands. A positive score represents a
positive attitude and a negative score a negative one. The rural sample includes farmers, the farmer sample is farmers alone and
the urban sample contains only urban responses. NFUS, National Farmers Union for Scotland; SCA, Scottish Countryside
Alliance; NTS, National Trust for Scotland; MTUK, Mammals Trust UK; SWT, Scottish Wildlife Trust; TfL, Trees for Life.
These attitudinal scores are from questionnaires filled in by the key informants within the organizations, who were asked to
represent the organization’s point of view in their responses. However, they represent unofficial opinion rather than the stated
policy of the organizations.
1000 E. B. Nilsen et al. Wolf reintroduction to Scotland
Proc. R. Soc. B (2007)
stocking rates for environmental reasons and those aiming
to advance social and animal welfare (Waterhouse 1996).
Given current global threats to biodiversity, the
re-establishment of extinct species into depauperate
natural communities in areas of low human population
density is a potentially useful conservation tool. However,
attempts to do this will always be contentious, costly and
impact local communities. These communities need to
support and benefit from any reintroductions to reduce
risks of disruption or sabotage to any reintroduction. Fear
of wolves can be a major hindrance to reintroductions
(Røskaft et al. 2003), although attacks on people by non-
rabid wolves are virtually non-existent (with the exception
of India; see Rajpurohit 1999). Killing of domestic dogs
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Our study suggests that the Scottish public, with the
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have been expected, and substantially less negative than
the attitudes expressed by their representative organiz-
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such attitudes may change in a more negative direction
Heberlein 2003). In this paper, we have suggested one
advantage of the reintroduction of wolves—solving some
of the difficult issues surrounding deer management in
towards wolf reintroduction, which is a prerequisite for a
successful reintroduction programme.
We are grateful to Mick Crawley, Nigel G. Yoccoz, John
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on an earlier version of this manuscript, the Norwegian
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NOTICE OF CORRECTION Download full-text
A Corrigendum to this article was published on 25 July 2007.