Journal of Applied Ecology 2015, 52, 544–551
doi: 10.1111/1365-2664.12415
POLICY DIRECTION
Developing fencing policies for dryland ecosystems
Sarah M. Durant1,2,*, Matthew S. Becker3,4, Scott Creel4, Sultana Bashir5, Amy J.
Dickman6, Roseline C. Beudels-Jamar7,8, Laly Lichtenfeld9,10, Ray Hilborn11, Jake Wall12,
George Wittemyer13,14, Lkhagvasuren Badamjav15, Stephen Blake16, Luigi Boitani17,
Christine Breitenmoser18, Femke Broekhuis6,19, David Christianson20, Gabriele Cozzi21,
Tim R. B. Davenport22, James Deutsch2, Pierre Devillers7,8, Luke Dollar23,24,25, Stephanie
€ ge3,4, Emily FitzHerbert6, Charles Foley22,
Dolrenry26, Iain Douglas-Hamilton14,27, Egil Dro
Leela Hazzah26, J. Grant C. Hopcraft28, Dennis Ikanda29, Andrew Jacobson1,30, Dereck
Joubert23, Marcella J. Kelly31, James Milanzi32, Nicholas Mitchell2,33, Jassiel M’Soka3,4,34,
Maurus Msuha29, Thandiwe Mweetwa3,20, Julius Nyahongo35, Elias Rosenblatt3,4, Paul
Schuette3,36, Claudio Sillero-Zubiri6, Anthony R. E. Sinclair37, Mark R. Stanley Price6,
Alexandra Zimmermann6 and Nathalie Pettorelli1
1
Institute of Zoology, Zoological Society of London, Regents Park, London NW1 4RY, UK; 2Wildlife Conservation
Society, Bronx Zoo, 2300 Southern Blvd, Bronx, NY 10460, USA; 3Zambian Carnivore Programme, Box 80, Mfuwe,
Eastern Province, Zambia; 4Conservation Biology and Ecology Program, Department of Ecology, Montana State
University, 310 Lewis Hall, Bozeman, MT 59717, USA; 5Tanglin International Centre, Birdlife International, 354 Tanglin
Road, #01-16/17, Singapore City 247672, Singapore; 6Wildlife Conservation Research Unit, Department of Zoology,
The Recanati-Kaplan Centre, University of Oxford, Tubney House, Tubney OX13 5QL, UK; 7Royal Belgian Institute of
Natural Sciences, 29 rue Vautier, 1000 Bruxelles, Belgium; 8CMS Scientific Council, UNEP/CMS, Hermann-EhlersStr. 10, 53113 Bonn, Germany; 9African People & Wildlife Fund, PO Box 624, Bernardsville, NJ 07924, USA; 10Yale
School of Forestry and Environmental Studies, 195 Prospect St, New Haven, CT 06511, USA; 11School of Aquatic
and Fishery Sciences, University of Washington, Seattle, WA 98195, USA; 12Laboratory for Advanced Spatial
Analysis, Department of Geography, University of British Columbia, 1984 West Mall, Vancouver, BC V6T 1Z2,
Canada; 13Fish, Wildlife and Conservation Biology, Colorado State University, Fort Collins, CO 80523, USA; 14Save
the Elephants, PO Box 54667, Nairobi, Kenya; 15CMS Scientific Council & Mongolian Academy of Sciences, Jukov
Avenue 77, Ulaanbaatar 51, Mongolia; 16Max Planck Institute for Ornithology, Whitney R. Harris World Ecology
Center, University of Missouri-St. Louis, B216 Benton Hall, One University Boulevard, St. Louis, MO 63121-4400,
USA; 17Department of Biology and Biotechnologies, Università di Roma La Sapienza, Viale Università 32, 00185
Roma, Italy; 18Co-Chair IUCN/SSC Cat Specialist Group, c/o KORA, Thunstrasse 31, 3074 Muri, Switzerland; 19Mara
Cheetah Project, Kenya Wildlife Trust, PO Box 86, 00502 Karen, Nairobi, Kenya; 20School of Natural Resources and
the Environment, University of Arizona, Biological Sciences East 325, Tucson, AZ 85721, USA; 21Institute of
Evolutionary Biology and Environmental Studies, Zurich University, Winterthurerstrasse 190, CH – 8057 Zu€rich,
Switzerland; 22Tanzania Program, Wildlife Conservation Society, PO Box 922, Zanzibar, Tanzania; 23Big Cats
Initiative, National Geographic Society, 1145 17th Street NW, Washington, DC 20036-4688, USA; 24Department of
Biology, Pfeiffer University, Misenheimer, NC 28109, USA; 25Nicholas School of the Environment, Duke University,
Durham, NC 27708, USA; 26Lion Guardians, PO Box 15550, Langata, Kenya; 27Department of Zoology, University of
Oxford, Oxford OX1 3PS, UK; 28Institute of Biodiversity, Animal Health and Comparative Medicine, University of
Glasgow, University Avenue, Glasgow G12 8QQ, UK; 29Tanzania Wildlife Research Institute, PO Box 661, Arusha,
Tanzania; 30Department of Geography, University College London, London WC1E 6BT, UK; 31Department of Fish &
Wildlife Conservation, Virginia Tech, 146 Cheatham Hall, Blacksburg, VA 24061-0321, USA; 32Western Region,
Zambia Wildlife Authority, Private Bag 1, Chilanga, Zambia; 33Conservation Programmes, Zoological Society of
London, Regents Park, London NW1 4RY, UK; 34Zambia Wildlife Authority, Private Bag 1, Chilanga, Zambia;
35
College of Natural and Mathematical Sciences, University of Dodoma, PO Box 259, Dodoma, Tanzania; 36College
of Environmental Science and Forestry, State University of New York, 1 Forestry Dr, Syracuse, NY 13210, USA; and
37
Beaty Biodiversity Research Centre, University of British Columbia, 6270 University Boulevard, Vancouver, BC V6T
1Z4, Canada
*Correspondence author. E-mail: sdurant@wcs.org
© 2015 The Authors. Journal of Applied Ecology © 2015 British Ecological Society
Fencing policies for dryland ecosystems
545
Summary
1. In dryland ecosystems, mobility is essential for both wildlife and people to access unpredictable and spatially heterogeneous resources, particularly in the face of climate change.
Fences can prevent connectivity vital for this mobility.
2. There are recent calls for large-scale barrier fencing interventions to address human–wildlife conflict and illegal resource extraction. Fencing has costs and benefits to people and wildlife. However, the evidence available for facilitating sound decision-making for fencing
initiatives is limited, particularly for drylands.
3. We identify six research areas that are key to informing evaluations of fencing initiatives:
economics, edge permeability, reserve design, connectivity, ecosystem services and communities.
4. Policy implications. Implementing this research agenda to evaluate fencing interventions in
dryland ecosystems will enable better management and policy decisions. The United Nations
Conventions on Migratory Species (CMS) and to Combat Desertification (UNCCD) are
appropriate international agreements for moving this agenda forward and leading the development of policies and guidelines on fencing in drylands.
Key-words: barriers, biodiversity conservation, conservation policy, deserts, ecosystem function, management interventions, migration, nomadic pastoralism, rangelands, transhumance
A resurgence in calls for large-scale fencing
interventions in Africa
Fencing has been used world-wide for a variety of purposes, including protecting remnant wildlife populations
from overhunting, poaching or invasive species and reducing human–wildlife conflict and human encroachment
(Somers & Hayward 2012). In Africa, after a proliferation
of fencing initiatives in the 1960s and 1970s, there has
been a recent resurgence in calls for large-scale fencing to
protect biodiversity and to separate wildlife from people,
livestock and crops. For example, Uganda intends to
fence all of its national parks in a bid to stem human–
wildlife conflict (Government of Uganda 2012). The
Rwandan authorities recently erected a 120-km fence
around the Akagera National Park at a capital cost of
$25 million in a bid to eliminate human–wildlife conflict
(Hall 2013). Meanwhile, the government of Malawi has
stated a wish to protect all parks in the country with electric fences (Kafemveka 2013).
In stark contrast, elsewhere in Africa, authorities are
removing fences to restore wildlife populations and migratory movements and to promote wildlife-based economies
for conservancies and local communities. The Southern
African Development Community (SADC) in the Phakalane Declaration has recently recommended strategic
realignment of veterinary cordon fences (erected for wildlife disease control) to counteract the harmful impacts of
fences on wildlife populations (SADC 2012). In addition,
the non-governmental organization (NGO)-led Transfrontier Conservation Area and privately led conservancy
movements across Africa are encouraging the widespread
removal of fencing to re-establish large-scale animal
movements (Van Aarde & Jackson 2007; WCS 2008;
Lindsey, Roma~
nach & Davies-Mostert 2009). Their aim is
to support or restore wide-ranging species whose populations are no longer viable in small reserves.
Scientific opinion on the topic of fencing appears similarly divided. A recent analysis of African lion Panthera
leo densities and growth rates from fenced and unfenced
populations concluded that fencing was a cost–effective
conservation strategy for this species and recommended
fencing as a primary conservation tool for lions (Packer
et al. 2013). However, Creel et al. (2013) demonstrated
that the studied populations differed in key aspects other
than fencing, with fenced populations having markedly
higher budgets for substantially smaller areas, which often
held intensively managed lion populations well above carrying capacity. In concert, these factors confounded the
original analyses and prompted a reanalysis to test for
correlates of population size, rather than the proximity of
a population to its carrying capacity (Creel et al. 2013).
This reanalysis found the opposite result that many more
lions are conserved per dollar invested in unfenced than
in fenced reserves, while also avoiding the ecological and
economic costs of fencing (Creel et al. 2013). While the
proximity of a population to its carrying capacity (Packer
et al. 2013) is a useful measure of conservation success,
population size is generally of greater importance for decisions about conservation priorities (Creel et al. 2013),
because many populations near carrying capacity are also
very small. This debate prompted a subsequent article in
Science that highlighted the problems associated with
large-scale fencing and concluded that, as climate change
increases the importance of wildlife mobility and landscape
connectivity, fencing of wildlife should become an action
of last resort (Woodroffe, Hedges & Durant 2014).
To reconcile such widely divergent opinions and contradictory policies, we review and identify key information
needs for conservation policymakers and practitioners for
© 2015 The Authors. Journal of Applied Ecology © 2015 British Ecological Society, Journal of Applied Ecology, 52, 544–551
546 S. M. Durant et al.
better assessment of costs and benefits of proposed fencing interventions. Critical evaluation of fencing initiatives
is most urgent in the world’s dryland ecosystems where
mobility is essential for both wildlife and people to access
temporally variable and spatially heterogeneous resources
(Notenbaert et al. 2012). In such landscapes, the erection
of large-scale impermeable barriers may reduce connectivity and lead to significant ecological and economic
impacts (Okin et al. 2009).
We define drylands as those areas with an aridity index
value of <065, in accordance with the Millennium Ecosystem Assessment (Safriel et al. 2005; Fig. 1), the United
Nations Environmental Programme (UNEP), the International Union for the Conservation of Nature (IUCN) and
the Convention on Biological Diversity (CBD) (Davies
et al. 2012). These areas cover 41% of the land’s surface
and are home to an estimated 64% of all bird, 55% of
mammal and 25% of amphibian species (Davies et al.
2012). They support some of the world’s largest populations of terrestrial megafauna and significant wildlife
migratory systems (Harris et al. 2009; Milner-Gulland,
Fryxell & Sinclair 2011). Moreover, two billion people live
in drylands, including some of the most vulnerable and
marginalized communities in the world (Middleton et al.
2011). Survival of wildlife and people in these arid lands
has depended on adapting to a harsh and highly variable
environment, characterized by short growing seasons and
low, unpredictable rainfall that are not conducive to agriculture. Historically, people living in drylands depended
on nomadic or semi-nomadic pastoralism, a strategy that
allows the most efficient use of highly variable and localized rainfall (McCabe 2004; Homewood 2009). Thus, in
unpredictable dryland environments, mobility is critical to
access transient forage and water resources for both wildlife and people (Notenbaert et al. 2012).
Costs and benefits of fencing in dryland
ecosystems
Fences are free-standing structures aimed at restricting or
preventing movement across boundaries (Hayward & Kerley 2009). Fences are usually erected to reduce threats to
wildlife from direct human activities (such as ecosystem
degradation, harvesting, persecution and disturbance);
reduce conflict between people and wildlife (Lindsey et al.
2012); and reduce disease transmission between wildlife
and domestic animals, most notably the extensive veterinary barrier fences stretching across southern Africa
(Gadd 2012). Fencing is widely used in Australian
drylands to exclude invasive non-native species from wildlife areas, though the maintenance and construction costs
incurred in building fences able to exclude small invasive
predators generally keep such fenced areas relatively small
(Dickman 2012).
While we can relatively easily identify the potential benefits, the negative consequences of large-scale fencing
interventions may be less obvious. Large-scale fencing can
disrupt migration pathways and reduce access to key
areas within drylands, such as seasonal foraging areas
(Harris et al. 2009) and wetland refuges (Davies et al.
2012). This can lead to severe reductions in migratory or
nomadic ungulate populations and may prompt wider
impacts on non-migratory species (Harris et al. 2009;
Gadd 2012). Some impacts may occur over a long time,
which makes them particularly difficult to detect (Norrdahl et al. 2002). Fencing also restricts ranging of keystone species, such as African elephants Loxodonta
Africana, which significantly influence ecosystem structure
and function (Shrader, Pimm & Van Aarde 2010; Asner
& Levick 2012). The potentially damaging habitat impacts
arising from ‘compressing’ elephants within protected
areas have been well documented (Western & Gichohi
1993; Douglas-Hamilton, Krink & Vollrath 2005; Loarie,
Van Aarde & Pimm 2009). Similarly, fencing may also
cause disruption at high trophic levels, such as altering
the population dynamics or restricting movement of top
predators, which is likely to lead to cascading impacts,
loss of ecosystem function and impoverished biodiversity
(Estes et al. 2011). Implementing intensive and expensive
management to mitigate against such effects, such as
translocation or anthropogenic control of population size
(e.g. see discussion of lions in Packer et al. 2013; Creel
et al. 2013), may not be feasible or cost effective, particularly for multiple species, and is unlikely to provide an
adequate replacement for naturally regulated and connected ecosystems.
Fig. 1. The world’s dryland zones based
on an aridity index <065 (Safriel et al.
2005).
© 2015 The Authors. Journal of Applied Ecology © 2015 British Ecological Society, Journal of Applied Ecology, 52, 544–551
Fencing policies for dryland ecosystems
Keeping wildlife in or people out?
A well-constructed, well-maintained fence can be wildlife
proof, but can never be human proof. Even the most
heavily fortified fences have not prevented the illegal killing of white rhinoceros Ceratotherium simum and black
rhinoceros Diceros bicornis in South Africa over recent
years (Woodroffe, Hedges & Durant 2014). People are
likely to be able to circumvent any fence, but they may
also destroy fences in order to gain access to useful
resources on the other side of the barrier, such as bushmeat, ivory, honey, medicinal plants and grazing. In
doing so, they may make the fence permeable to wildlife,
and sometimes wildlife may not be able to find their way
back through the fence. The fence itself may also serve as
a readily available source of snare wire, rendering a fence
erected to protect wildlife from bushmeat extraction
counterproductive (Lindsey et al. 2011, 2013; Becker
et al. 2013). Alternative fencing materials, such as kinked
mesh wire, can reduce this risk, but they are not well
known to local management agencies, difficult to source
and more expensive. Thus, they are less likely to be
adopted, particularly in government fencing programmes
that may be focused more on protecting people than
wildlife.
A fence can reduce human–wildlife conflict, but may
also prevent people from accessing benefits from nature
and adversely impact the development of communitybased incentives for wildlife conservation (East et al.
2012; Gadd 2012). Moreover, a fence may also contribute
to the loss of coping strategies that have enabled communities to coexist with wildlife. Thus, if a fence, after erection, is lost or breached, human–wildlife conflict may
reach levels much higher than those that existed prior to
the establishment of the fence (Gadd 2012). Hence, it is
critical that, once erected, a fence is maintained as an
impermeable barrier. Wildlife often inflicts small breaches
in a fence, necessitating frequent and costly ongoing
maintenance to sustain its effectiveness as a barrier
(Lindsey, Roma~
nach & Davies-Mostert 2009; Kesch,
Bauer & Loveridge 2013). Thus, the initial capital construction costs are only a small part of the investment
required.
Developing an evidence base to evaluate
dryland fencing interventions
Scientific understanding of the costs and benefits of fences
is still in its infancy (Somers & Hayward 2012) and is currently inadequate to support sound policymaking. Here,
we identify six research areas where incomplete or poor
information hinders the wise use of fencing (Table 1). For
the purposes of this discussion, we consider perimeter
fencing of reserves, but our analysis is relevant for other
large-scale fencing interventions, such as the increasing
use of fencing to safeguard oil or gas pipelines and transport networks.
547
1. Economics. Economic costs form the basis for many
conservation policies, but we still know very little about
the ability of different conservation interventions, including fencing, to deliver conservation success for a given
cost (McCreless et al. 2013). This makes it very difficult
to assess the relative expenditure to benefit ratio of fencing against other alternative interventions (Possingham
et al. 2001). Yet, the economic assessment of fencing is
fundamental to sound policy decisions since limited conservation resources must be spent wisely to deliver sustainable solutions and maximize conservation impact. The
only economic analyses conducted on the efficacy of fencing do not control for the apportioning of the overall
budget to other reserve management activities (i.e. Creel
et al. 2013; Packer et al. 2013), and only the most wellfinanced reserves are able to afford fencing interventions.
Thus, it is not possible to disentangle the benefits of fencing from those of other investments such as anti-poaching
efforts, community engagement, infrastructure investment
and other activities that potentially confound the effect of
fences on the effectiveness of a reserve and the density of
a focal species. Without such an analysis, it is impossible
to ascertain whether a budget increase, which allows fencing interventions and subsequent management, would
deliver better outcomes for conservation and communities
compared with investing the same funds in other reserve
management strategies, such as community engagement
and anti-poaching, without any fencing. A proper comparison of alternative strategies using long-term data and
metrics of conservation success must include short-term
capital costs, which can be considerable for fencing, as
well as recurring maintenance costs.
2. Edge permeability. Fencing an already existing abrupt
transition (i.e. ‘hard edge’) between a reserve and the surrounding anthropogenically modified landscape can be
part of the justification for fencing interventions. Fencing
of such habitat edges prevents the movement of wildlife
beyond the reserve, where they might forage in crops or
kill livestock. A presumed ‘hard edge’ suggests that negative impacts on wildlife from the fence due to restriction
in movement will be minimal since the surrounding modified landscape is often viewed as comprising marginal
habitat. Yet, the actual permeability of the edge will be
species- and system specific, as well as context specific
(Ries & Sisk 2010). Understanding what constitutes a
hard edge for different species in the context of overall
conservation and management objectives of fencing interventions is necessary to assess whether a ‘hard edge’ justification is appropriate.
3. Reserve design. A landscape perspective on fencing
implementation is critical as the impacts of a fence on
wildlife, ecosystems and communities depend on its location relative to the broader ecological context (Soule &
Terborgh 1999). Dryland protected areas often have
boundaries delineated by key resources that may be
shared by wildlife and humans, such as major rivers that
© 2015 The Authors. Journal of Applied Ecology © 2015 British Ecological Society, Journal of Applied Ecology, 52, 544–551
548 S. M. Durant et al.
Table 1. Evidence needs and potential data that can be used to evaluate fencing interventions in drylands
Research
issue
Question
Evidence needs
Data
Is fencing a
cost–effective and
sustainable approach
to deliver
conservation success?
How do different conservation activities compare with
fencing under similar operating budgets, bearing in
mind the substantial capital and maintenance costs
required for fencing?
Reserve expenditure reports broken
down by management activity
Edge
permeability
Does the boundary
to be fenced
constitute a
hard edge?
What is the definition of a hard edge and how does
this vary between species and ecosystems?
Remote sensing data
Reserve
design
How does the
reserve’s design
impact the costs
and benefits of
fencing?
What is the impact of reserve shape?
Protected area database
If reserve boundaries lie on key landscape features
and resources, such as rivers, then how will this
mediate the balance between costs and benefits of
fencing for wildlife and people?
Remote sensing data
Economics
Is fencing economically more or less sustainable
than other options?
Data on fence integrity
Measures of conservation success
Wildlife movement and distribution
data on the edge of protected areas
Geographic information system
(GIS) layers
Wildlife movement and distribution
data in relation to landscape
and resources
Contribution of resources to
local livelihoods
Connectivity
How important is
connectivity to the
overall goals of the
reserve and
ecosystem function?
How important are wildlife movements into
and out of reserves to their population viability?
How does a fence affect wildlife movements and does
it prevent wildlife from accessing key resources?
Which species are most vulnerable to reserve isolation?
What constitutes connectivity for these species?
What are the impacts from the restriction of
wildlife movement due to fencing on ecosystem
function?
Remote sensing data
GIS layers
Wildlife movement data in fenced
and unfenced areas
Wildlife habitat and resource use
data inside and outside the reserve
Map of potential barriers to movement
Map of potential areas of connectivity
Measures of immigration and
emigration for wide-ranging wildlife
Life-history and survivorship data for
wide-ranging and dispersing species
Ecosystem
services
How does the
establishment of a
fence impact
delivery of
ecosystem services?
What is the relationship between habitat subdivision
and carrying capacity? How does fencing affect
delivery of ecosystem services?
If the fence is to entirely enclose a reserve – how
will this affect the viability of low density and
wide-ranging species within the reserve? (If such
species require intensive management, then this
should be included in the economic costing of
the fencing intervention)
Remote sensing data
GIS layers
Protected area database
Wildlife surveys
Demographic data and population
viability modelling
Climate data and climate change
predictions
How does fencing affect the interactions between
ecosystem service delivery and rainfall and productivity?
How is climate change likely to affect ecosystem resilience
and how is this likely to be impacted by fencing?
Communities
What are the benefits
and costs to local
communities of
fencing and how are
these distributed
between individuals?
What legal and illegal benefits do the communities
derive from the presence of the reserve?
Game scout and ranger
patrol reports
How are these benefits distributed within the community?
Resource extraction data
What are the costs to communities from the presence
of the reserve?
Socio-economic data from
households within local
communities around fenced and
unfenced reserves including:
How are these costs distributed within the community?
How will fencing affect these costs and benefits?
Who is likely to benefit from fencing and by how
much, and who is likely to pay the costs and by
how much?
Wealth and livelihoods
Distribution of resources
Costs and benefits from wildlife
© 2015 The Authors. Journal of Applied Ecology © 2015 British Ecological Society, Journal of Applied Ecology, 52, 544–551
Fencing policies for dryland ecosystems
are accessed by both people and wildlife. Fencing interventions to separate people and wildlife may result in a
barrier preventing access to the resource for wildlife, preventing access for human communities, or both. Productive agricultural land or key habitats, such as wetlands,
may also border reserves (Watson et al. 2013) and play
key roles for ecosystem function and local communities.
The impacts of fencing in relation to the design of reserve
boundaries, and how to mitigate these impacts, need to be
better understood.
4. Connectivity. Connectivity is fundamental to the longterm viability of many wildlife populations, particularly
migratory and nomadic species common to dryland systems. Dryland reserves often do not cover the entire extent
of an animal’s range and may often be placed in either dry
or wet season ranges for migratory or nomadic species
(Fynn & Bonyongo 2011). In such situations, perimeter
fencing of reserves, preventing access to critical seasonal
resources, can lead to collapse in the populations of these
species (Gadd 2012). Moreover, access to ephemeral
resources may also be critical to the long-term survival of
some species. For example, foraging or water resources in
key areas outside a reserve may be important for the survival of long-lived species, such as elephants, during
extreme climatic events (Foley, Pettorelli & Foley 2008).
Identification of those species that are most vulnerable to
reserve isolation and developing a clear understanding as
to what constitutes connectivity for such species is key to
evaluating the ecological impacts of fencing interventions.
5. Ecosystem services. Beyond the specifics of the reserve
site and design, there is also a need to better understand
how the delivery of ecosystem services (e.g. soil and
watershed protection, timber, plant and animal harvesting) is compromised or enhanced by fencing initiatives.
Given the large-scale ecological processes that characterize
dryland systems and the dependence of people and wildlife on them, it is unlikely that fencing will have no
impact on ecosystem service delivery and access. Indeed,
studies show that simply subdividing land in drylands can
substantially reduce overall grazing carrying capacity
(Boone et al. 2005). Soil-based ecosystem services, such as
nutrient recycling and water capture, are particularly vulnerable to degradation in drylands (Parr et al. 1990), yet
there is no information on how these services may be
impacted by fencing. An understanding is needed as to
how fencing might hinder or help meet a reserve’s overall
biodiversity conservation goals and the continued delivery
of ecosystem services, as well as how this may be modified
by climate change.
6. Human communities. Many protected areas permit some
limited access for local communities, and some of the
poorest and most marginalized members of communities
may be particularly dependent on natural resources from
these areas (Loibooki et al. 2002; Brashares et al. 2011).
Fencing interventions are likely to make legitimate access
549
more difficult, and risk marginalizing these individuals
still further. Local communities are heterogeneous; some
individuals may suffer the costs of wildlife, in the form of
crop and livestock depredation for example, while others
may benefit from wildlife through tourism and hunting
revenue or associated ecosystem services (Thompson &
Homewood 2002), and hence, the costs and benefits of
fencing interventions are likely to be unevenly distributed
between households. While it is important that conservation interventions maintain the integrity of reserves, they
should avoid contributing to or exacerbating existing
inequities within communities. A better understanding of
the socio-economic impacts of fencing is needed to avoid
such unintended consequences on local communities.
The information from these six major research areas is
key to a proper evaluation of fencing interventions. Such
evaluations need to be carefully undertaken in the context
of the aims of the proposed fencing intervention. For
example, fences designed to keep wildlife in versus those
meant to keep people out are two substantially different
objectives, which in turn will likely have variable success and impacts. Any evaluation also needs to be undertaken in the context of the overall management goals for
each reserve; rarely, for example, are such goals focused on
a single species as per the analyses of Packer et al. (2013).
While the information required for these evaluations
may appear extensive, in reality, many of these research
areas can be addressed by collating and analysing existing
information, or by implementing targeted monitoring and
evaluation of new fencing interventions (Table 1). For
example, most protected areas have documented expenditure reports; measures of reserve design are available from
the protected area database; and remote sensing data can
be used to delineate edge permeability and monitor the
delivery of some key ecosystem services (Ayanu et al.
2012). There are, however, some areas where additional
information is required. For example, while research areas
such as ecosystem service delivery may be measured using
remote sensing data, there are others, such as wildlife
abundance or species diversity, which require direct sampling. There is also a need for improvements in our
understanding of movement patterns, and what constitutes barriers to movement, for many wide-ranging wildlife species. Such information could be provided through
fitting satellite or GPS collars to target species. Regardless
of the availability of ecological data, a clear information
gap is the socio-economic impacts of reserves on local
human communities, and there is a clear need for detailed
socio-economic studies on people living close to fenced
and unfenced wildlife areas.
Towards policy guidelines on large-scale
fencing interventions for drylands
It is clear that fences erected to protect wildlife or people
can be a useful conservation tool, but can also be coun-
© 2015 The Authors. Journal of Applied Ecology © 2015 British Ecological Society, Journal of Applied Ecology, 52, 544–551
550 S. M. Durant et al.
terproductive. Guidelines, which take into account species-specific requirements, ecological conditions and
human communities would help conservation practitioners
better evaluate large-scale fencing interventions. The United Nations Convention on Migratory Species (CMS) is
ideally suited to lead such guideline development, given
the CMS’s focus on wide-ranging species, experience with
fencing as a management tool, and recognized expertise in
conservation action for arid areas (e.g. CMS 2011).
The United Nations Convention to Combat Desertification (UNCCD), because of its mandate for sustainable
management of drylands, is also well placed to engage
with the breadth of the proposed research agenda. The
UNCCD is one of three treaties developed from the United Nations Earth Summit in 1992 and aims to prevent
and reverse land degradation and to mitigate the effects
of drought and is particularly relevant to developing
countries, where most drylands are located. As well as
CMS and UNCCD, the Food and Agriculture Organisation of the United Nations (FAO) has an important role
to play in the sustainable management of drylands.
Neither the CMS or UNCCD currently provides general policy guidelines as to the use of large-scale fencing,
nor does the FAO. Better understanding of the impacts of
fencing interventions would facilitate the development of
appropriate policies to help communities and governments
to improve sustainable management of drylands. Developing policies and guidelines for assessing when, where and
the type of fencing that should, or should not, be used in
drylands would help to prevent a repeat of the past harm
done by fences to people, wildlife and ecosystems. Preventing further degradation is likely to require solutions
within an integrated landscape approach to conservation
that acknowledges local communities as part of the ecosystems (IIED 2013).
Many large-scale fencing interventions are likely to
impact multiple countries; hence, it may also be useful to
make use of regional economic structures, such as the
SADC, East African Community (EAC), West African
Economic and Monetary Union (UEMOA) and South
Asian Association for Regional Cooperation (SAARC),
and target bilateral and multilateral donors, to enforce
guidelines and to help promote the need for full environmental impact assessments (EIA). These structures could
also be used to ensure that all large-scale fencing interventions have a practical and achievable long-term maintenance and financing plan to guarantee the long-term
integrity of the barrier once established. We recommend
active engagement of these organizations in contributing
to the improvement of knowledge of the impacts of fencing in drylands and in the development and implementation of policy guidelines.
Despite the high capital costs, fencing can initially
appear to be an easy solution. Yet, unless fencing strategies have local community support and a financing plan
to meet the expensive long-term costs of fence maintenance, there is a danger that they may generate more
problems than they solve. The research agenda proposed
will generate information necessary for better evaluation
of fencing interventions that take into account the full
range of likely impacts in dryland systems. Ultimately,
there is a need for funding agencies to increase support
for these areas and their marginalized peoples and
develop better management strategies to sustain dryland
ecosystems (Mortimore et al. 2009). The CMS and UNCCD could help to prevent further degradation of these
important systems by leading global efforts to develop an
understanding of the impacts of large-scale fencing interventions in drylands and establishing guidelines to regulate their use.
Acknowledgements
We thank Stuart Pimm and John Fryxell who provided constructive comments on the manuscript.
Data accessibility
Data have not been archived because this article does not contain
data.
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Received 17 July 2014; accepted 19 February 2015
Handling Editor: Marc Cadotte
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