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Fiddling in biodiversity hotspots while deserts burn? Collapse of the Sahara's megafauna

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Biodiversity hotspots understandably attract considerable conservation attention. However, deserts are rarely viewed as conservation priority areas, due to their relatively low productivity, yet these systems are home to unique species, adapted to harsh and highly variable environments. While global attention has been focused on hotspots, the world’s largest tropical desert, the Sahara, has suffered a catastrophic decline in megafauna. Of 14 large vertebrates that have historically occurred in the region, four are now extinct in the wild, including the iconic scimitar-horned oryx (Oryx dammah). The majority has disappeared from more than 90% of their Saharan range, including addax (Addax nasomaculatus), dama gazelle (Nanger dama) and Saharan cheetah (Acinonyx jubatus hecki) – all now on the brink of extinction. Greater conservation support and scientific attention for the region might have helped to avert these catastrophic declines. The Sahara serves as an example of a wider historical neglect of deserts and the human communities who depend on them. The scientific community can make an important contribution to conservation in deserts by establishing baseline information on biodiversity and developing new approaches to sustainable management of desert species and ecosystems. Such approaches must accommodate mobility of both people and wildlife so that they can use resources most efficiently in the face of low and unpredictable rainfall. This is needed to enable governments to deliver on their commitments to halt further degradation of deserts and to improve their status for both biodiversity conservation and human well-being. Only by so-doing will deserts be able to support resilient ecosystems and communities that are best able to adapt to climate change.
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BIODIVERSITY
VIEWPOINT
Fiddling in biodiversity hotspots while
deserts burn? Collapse of the Sahara’s
megafauna
S. M. Durant
1,2
*, T. Wacher
3
, S. Bashir
4
, R. Woodroffe
1
, P. De Ornellas
3
,
C. Ransom
3
, J. Newby
5
,T.Ab
aigar
6
, M. Abdelgadir
7
, H. El Alqamy
8
,
J. Baillie
3
, M. Beddiaf
9
, F. Belbachir
1,10
, A. Belbachir-Bazi
10
,
A. A. Berbash
11
, N. E. Bemadjim
12
, R. Beudels-Jamar
13
, L. Boitani
14
,
C. Breitenmoser
15
, M. Cano
6
, P. Chardonnet
16
, B. Collen
17
,
W. A. Cornforth
1
, F. Cuzin
18
, P. Gerngross
19
, B. Haddane
20
,
M. Hadjeloum
21
, A. Jacobson
1
, A. Jebali
22
, F. Lamarque
23
, D. Mallon
24
,
K. Minkowski
25
, S. Monfort
26
, B. Ndoassal
12
, B. Niagate
27
, G. Purchase
2,3
,
S. Sama
ıla
28
, A. K. Samna
28
, C. Sillero-Zubiri
29
, A. E. Soultan
30
,
M. R. Stanley Price
29,31
and N. Pettorelli
1
1
Institute of Zoology, Zoological Society of
London, Regents Park, London NW1 4RY,
UK,
2
Wildlife Conservation Society, Bronx
Zoo, 2300 Southern Blvd., Bronx NY 10460,
USA,
3
Conservation Programmes, Zoological
Society of London, London NW1 4RY, UK,
4
Birdlife International Asia, 247672,
Singapore,
5
Sahara Conservation Fund,
1148, L’Isle Switzerland,
6
Estacion
Experimental de Zonas
Aridas (EEZA),
CSIC, Carretera de Sacramento s/n, Almer
ıa
Spain,
7
Department of Biology, University of
Hail, Hail Saudi Arabia,
8
Egyptian
Environmental Affairs Agency (EEAA),
Cairo Egypt,
9
Office National du Parc
Culturel du Tassili n’Ajjer, Djanet 33100,
Algeria,
10
Laboratoire d’Ecologie et
Environnement, Faculte
´des Sciences de la
Nature et de la Vie, Universite
´de Be
´ja
ıa,
06000, Be
´ja
ıa Algeria,
11
Nature
Conservation Department, Environment
General Authority (EGA), Tripoli Libya,
12
Direction des Parcs Nationaux des Re
´serves
de Faune et de la Chasse, N’Djamena
Tchad,
13
Royal Belgian Institute of Natural
Sciences, 1000, Bruxelles Belgium,
14
Department Biology & Biotechnologies,
Universita
`La Sapienza, Viale Universit
a 32,
00185, Rome Italy,
15
Co-Chair IUCN/SSC
Cat Specialist Group, 3074, Muri Bern
Switzerland,
16
La Fondation Internationale
pour la Gestion de la Faune 75003, Paris
France,
17
Centre for Biodiversity &
Environment Research, University College
London, London WC1E 6BT, UK,
18
BP 1172
ABSTRACT
Biodiversity hotspots understandably attract considerable conservation atten-
tion. However, deserts are rarely viewed as conservation priority areas, due to
their relatively low productivity, yet these systems are home to unique species,
adapted to harsh and highly variable environments. While global attention has
been focused on hotspots, the world’s largest tropical desert, the Sahara, has
suffered a catastrophic decline in megafauna. Of 14 large vertebrates that have
historically occurred in the region, four are now extinct in the wild, including
the iconic scimitar-horned oryx (Oryx dammah). The majority has disappeared
from more than 90% of their Saharan range, including addax (Addax nasoma-
culatus), dama gazelle (Nanger dama) and Saharan cheetah (Acinonyx jubatus
hecki)all now on the brink of extinction. Greater conservation support and
scientific attention for the region might have helped to avert these catastrophic
declines. The Sahara serves as an example of a wider historical neglect of
deserts and the human communities who depend on them. The scientific com-
munity can make an important contribution to conservation in deserts by
establishing baseline information on biodiversity and developing new
approaches to sustainable management of desert species and ecosystems. Such
approaches must accommodate mobility of both people and wildlife so that
they can use resources most efficiently in the face of low and unpredictable
rainfall. This is needed to enable governments to deliver on their commitments
to halt further degradation of deserts and to improve their status for both
biodiversity conservation and human well-being. Only by so-doing will deserts
be able to support resilient ecosystems and communities that are best able to
adapt to climate change.
Keywords
Drylands, large carnivores, mammal distribution, ostrich, UNCCD, ungulates.
DOI: 10.1111/ddi.12157
114 http://wileyonlinelibrary.com/journal/ddi ª2013 John Wiley & Sons Ltd
Diversity and Distributions, (Diversity Distrib.) (2014) 20, 114–122
A Journal of Conservation Biogeography
Diversity and Distributions
Bab Agnaw, 40000, Marrakech Morocco,
19
BIOGEOMAPS, Umwelt-PR Gerngross
e.U., A-1070, Vienna Austria,
20
Fondation
Mohamed VI pour la Protection de
l’Environnement-Rabat Maroc/Programme
Biodiversity, Rabat Morroco,
21
Direction
Ge
´ne
´rale des Fore
ˆts, Direction de la
Protection de la Faune et de la Flore, Chef
de Bureau de la Gestion et de la
Pre
´servation de la Faune, Algiers Algeria,
22
Tunisia Wildlife Conservation Society
(TWCS), De
´partement de Biologie, Faculte
´
des Sciences de Tunis, Campus Universitaire,
2092, Tunis Tunisia,
23
Ministe
`re de
l’Ecologie, du De
´veloppement Durable et de
l’Energie – Sous-direction de la protection et
de la valorisation des espèces et de leur
milieu, 92055, La Défense CEDEX France,
24
Division of Biology and Conservation
Ecology, Manchester Metropolitan
University, Manchester M1 5GD, UK,
25
2395 Delaware Ave., #66 Santa Cruz CA,
95060, USA,
26
Smithsonian Conservation
Biology Institute, National Zoological Park,
Front Royal VA, USA,
27
Directeur du Parc
National et Re
´serve de Biosphe
`re de la
Boucle du Baoule
´, BP 275, Bamako Mali,
28
Direction de la Faune, de la Chasse et des
Aires Prote
´ge
´e, BP 578, Niamey Niger,
29
Wildlife Conservation Research Unit,
Department of Zoology, University of
Oxford, The Recanati-Kaplan Centre,
Tubney OX13 5QL, UK,
30
St Katherine
Protectorate, Nature Conservation Sector,
Egyptian Environmental Affairs Agency
(EEAA), Cairo Egypt,
31
Al Ain Zoo, Abu
Dhabi Saudi Arabia
*Correpondence: S. M. Durant, Institute of
Zoology, Zoological Society of London,
Regents Park, London NW1 4RY, UK.
E-mail: s.durant@ucl.ac.uk
THE IMPORTANCE OF DESERT ECOSYSTEMS
Global biodiversity is being lost at rates that are unprece-
dented. Vertebrate species are declining at rates 1001000
times higher than those in evolutionary history (Dirzo &
Raven, 2003; Mace et al., 2005), and climate change is pro-
jected to increase extinction rates further (Thomas et al.,
2004; Foden et al., 2013). Conservation biologists have
argued convincingly that targeting funding at tropical forests
and other ‘biodiversity hotspots’ maximizes the number of
species conserved per conservation dollar (Kerr, 1997;
Mittermeier et al., 1998; Reid, 1998; Myers et al., 2000;
Brooks et al., 2002; Sechrest et al., 2002). Concerns about
climate change have further focused attention on forests,
because forest degradation and loss is responsible for a
significant proportion of anthropogenic greenhouse gas emis-
sions; hence, maintaining forest cover is a potentially cost-
effective mechanism for climate change mitigation (Denman
et al., 2007; Nabuurs et al., 2007).
However, prioritization of forests and biodiversity hotspots
for conservation has inevitably resulted in the neglect of
important biodiversity in other biomes (Grenyer et al.,
2006). In particular, desert biodiversity has attracted rela-
tively little conservation finance and action (Davies et al.,
Diversity and Distributions, 20, 114–122, ª2013 John Wiley & Sons Ltd 115
Collapse of the Sahara’s megafauna
2012; Durant et al., 2012), although deserts cover 17% of the
world’s land mass and harbour surprisingly high biodiversity
(Safriel et al., 2005), despite their low primary productivity
and consequent low biomass. In fact, the vast scale of desert
ecosystems results in relatively similar overall biodiversity to
forests at the biome level, despite the latter’s extremely high
biodiversity at smaller scales. For example, deserts are home
to 25% of terrestrial vertebrate species and, combined with
xeric shrublands, are among the top three richest biomes for
terrestrial vertebrates (Mace et al., 2005; Millenium Ecosystem
Assessment, 2005). Desert biodiversity can yield important
insights into the physiological and genetic basis of species
tolerance to water stress and extreme temperatures. Such
knowledge can improve dryland agricultural practices and
conservation management, and may even be relevant to
human health; information that is critical to adaptation to a
changing climate (Merkt & Taylor, 1994; Mueller & Diamond,
2001; Darkoh, 2003).
Desert and other dryland ecosystems also provide vital
resources for human communities. Six per cent of the
world’s human population inhabit deserts (Mortimore et al.,
2009), including some of ‘the poorest, the hungriest, the least
healthy and most marginalized people in the world’ (Middle-
ton et al., 2011). Human desert communities inhabit an
exceptionally harsh and unpredictable environment and are
especially vulnerable to the impacts of ecosystem degradation
and the disruption of critical ecosystem services (Mortimore
et al., 2009). However, as with desert biodiversity, the plight
of desert-dwelling people has gained little global attention.
The UN Convention to Combat Desertification (UNCCD), a
convention specifically designed to address the needs of such
communities, remains one of the weakest of the UN conven-
tions (Conliffe, 2011). Lack of funding and political will have
meant that progress towards the UNCCD’s goal of reversing
land degradation and desertification has been elusive (Tollef-
son & Gilbert, 2012). Meanwhile the people living in these
environments continue to be perceived as peripheral and
unimportant and are neglected by political and business
communities (Middleton et al., 2011).
Desert peoples and ecosystems are likely to face even greater
challenges in the near future, because the rate of climate
change is projected to be particularly high in the desert biome
(Loarie et al., 2009). Yet deserts also have substantial potential
to contribute to climate regulation. The vast extent of deserts
and other dryland ecosystems harbour an estimated one-third
of terrestrial global carbon stock (Trumper et al., 2008), with
further potential for carbon sequestration through improved
land management (Keller & Goldstein, 1998; Lal, 2001).
THE SAHARA A FORGOTTEN DESERT
Desert ecosystems have not only been neglected by the con-
servation and development communities, but they have also
received disproportionately little scientific attention
compared with other biomes. Between 2000 and 2011, the
majority of scientific publications in ecology focused on the
forest biome (67%) and only a minority on deserts (9%)
(Durant et al., 2012). The Sahara, the world’s largest desert,
harbours iconic large mammal biodiversity, yet has attracted
very little scientific attention. Over the same period, only 31
ISI ecology papers were focused on aspects of Saharan biodi-
versity
Moreover, a recent review by Brito et al. (2013) con-
firms that there has been little biodiversity research in the
Sahara over the last decade and that the central Sahara has
been almost entirely neglected.
The lack of scientific attention given to desert biodiversity
is mirrored by a lack of financial support. Although the Sah-
aran nations cover 43% of Africa’s land mass, they only
received 12% of Global Environment Facility funding to
Africa over the period 19912009 (Global Environmental
Facility, 2010; Durant et al., 2012). Similarly, only 1% of
funds provided by the UK’s Darwin Initiative between 1992
and 2008 went to projects in desert biomes, compared with
23% to forests over the same period (Hardcastle, 2008;
Durant et al., 2012). Such low levels of research and funding
can allow key species to disappear from desert landscapes
largely unreported and unnoticed by conservationists and
scientists.
Two workshops organized by the Zoological Society of
London and the Wildlife Conservation Society in 2010 and
2012 have shed long overdue light on the status of large ver-
tebrate biodiversity in the Sahara. These workshops used an
expert-based mapping process (Sanderson et al., 2002;
IUCN/SSC, 2006, 2007a,b, 2008, 2012) to establish current
areas of known resident range for 14 species and subspecies
of large vertebrate found in the Saharan region. These taxa
include all of the large herbivores and all but one of the large
carnivores found in the region. The presence of both groups
is indicative of effective ecosystem function and management
(Estes et al., 2011; Fritz et al., 2011; Poisot et al., 2013). The
single species not included in the analysis was the striped
hyena (Hyaena hyaena), for which little distributional
information is available.
Participants in the mapping process were species experts
and protected area managers who contributed data on the
species’ distribution and status, drawing upon their own and
their colleagues’ information and experience. In this process,
the Sahara was defined as land receiving <250 mm annual
rainfall, covering a total area of 9,775,572 km
2
. Each species
was mapped in turn. All land formerly occupied by the spe-
cies before major anthropogenic change (agreed to be prior
to c. 1800) was considered to fall inside the historical range.
For many areas, detailed historical data on distribution were
available; elsewhere, historical distribution was estimated
based on the species’ broad habitat requirements. Point loca-
tions of species presence were used to help delineate geo-
graphic range polygons of current resident range. Current
ISI Web of Science http://wok.mimas.ac.uk, 17 Oct 2013, search,
subject area ecology, including ‘Sahara’. 130 publications found of
which 31 included information on biodiversity in the Sahara desert
(most referred to sub-Saharan Africa).
116 Diversity and Distributions, 20, 114–122, ª2013 John Wiley & Sons Ltd
S. M. Durant et al.
range was land where participants agreed that the species was
known or was highly likely to be still resident. This was gen-
erally defined as land where there was evidence of the species
being present within the last 10 years. However, for areas
where there had been little or no ground-based surveying in
recent years, resident range could include land, which con-
tained suitable habitat and/or prey, provided it was connected
to the known range of the species. At the workshop, maps
were reviewed and modified through discussion among par-
ticipants. The maps were circulated to participants unable to
attend the workshop in person, in order to reach an expert
consensus on current and historical distributions. These maps
were then used to evaluate the proportions of each species’
current geographic range compared with historical range.
Of the 14 species and subspecies assessed, 10 (71%) are
endemic to the Sahara or the wider SaheloSaharan region
and 12 (86%) are considered by the IUCN Red List to be
either extinct in the wild or globally threatened with extinc-
tion (Table 1). The maps (shown in Fig. 1) clearly show a
massive collapse in large vertebrate distributions across the
region. Thirteen of the 14 species have disappeared from
66% or more of their historical Saharan range, and nine spe-
cies have disappeared from 90% or more of their range
(Table 1, Fig. 1). Shockingly, half of the 14 species are either
regionally extinct or confined to 1% or less of their historical
range. The range collapse of the species still extant raises
serious concerns for their future survival in the region; only
the Nubian Ibex (Capra nubiana) still inhabits most of its
historical range, but even this species is classified as vulnera-
ble, due to numerous threats throughout its range, including
widespread hunting (Alkon et al., 2008).
Difficulties in access for conservationists and other key
actors due to lack of roads and a hostile terrain, exacerbated
by past and ongoing instability across the region, have
undoubtedly contributed to the declines of this iconic desert
fauna (Brito et al., 2013). Widespread and unsustainable
hunting is also reported to have posed a significant threat to
vertebrates across the region (Beudels-Jamar et al., 2006;
Brito et al., 2013). However, it is difficult to escape the con-
clusion that lack of financial support and scientific attention
Table 1 Percentage loss of range compared with historical range for 14 species of large vertebrate in the Saharan region. Estimates
calculated from maps in Fig. 1.
Species Scientific name
IUCN Red
List status
Endemic to the
SaheloSaharan
region?
Historical
range (km
2
)
Current known
resident range (km
2
) % range loss
Scimitar-
horned
oryx
Oryx dammah Extinct in the
Wild
Yes 1,543,784 0 100
Addax Addax
nasomaculatus
Critically
Endangered
Yes 6,911,931 47,155 99
Bubal
hartebeest
Alcelaphus
buselaphus
buselaphus
Extinct Yes 500,969 0 100
Dorcas
gazelle
Gazella dorcas Vulnerable Yes 9,739,599 1,357,723 86
Nubian ibex Capra nubiana Vulnerable No 320,636 287,902 10
Barbary
sheep
Ammotragus lervia Vulnerable Yes 2,361,570 535,031 77
Slender
horned
gazelle
Gazella leptoceros Endangered Yes 1,298,549 182,005 86
Cuvier’s
gazelle
Gazella cuvieri Endangered Yes 279,525 96,330 66
Dama
gazelle
Nanger dama Critically
Endangered
Yes 3,616,260 23,720 99
North
African
ostrich
Struthio camelus
camelus
Least Concern*Yes 9,421,600 18,710 99.8
Leopard Panthera pardus Near
Threatened
No 891,817 29,221 97
Saharan
cheetah
Acinonyx jubatus
hecki
Critically
Endangered
Yes 8,360,570 813,947 90
African
wild dog
Lycaon pictus Endangered No 2,606,295 0 100
Lion Panthera leo Vulnerable No 738,644 0 100
*Saharan race morphologically and genetically distinct but Red List status not yet assessed.
Diversity and Distributions, 20, 114–122, ª2013 John Wiley & Sons Ltd 117
Collapse of the Sahara’s megafauna
have also played a role (e.g. Laurance, 2013). Despite this,
there have been some successes. Niger is to be congratulated
on its recent proclaimation of the 97,000 km
2
Re
´serve Natu-
relle Nationale du Termit et du Tin Toumma, which har-
bours around 150 of the world’s 200 remaining wild addax
and one of a handful of remaining populations of dama
gazelle. Chad also deserves support for its programme to
bring back scimitar-horned oryx, currently extinct in the
wild, to the Ouadi Rime
´-Ouadi Achim Game Reserve
(Bemadjim et al., 2012). These successes result from support
from organizations such as the Convention on Migratory
Species (CMS) (UNEP/CMS, 1999; Beudels-Jamar et al.,
2006), the Environment Agency Abu Dhabi, the Sahelo
Saharan Special Interest Group and the Sahara Conservation
Fund, which have stimulated a wide range of important
conservation efforts in the region.
All the Saharan nations require additional support if they
are to safeguard biodiversity effectively across such enormous
landscapes, particularly in the context of escalating conflicts
in the region (Brito et al., 2013). This can only be obtained
if the conservation and scientific communities increase their
focus on biodiversity in these hitherto neglected ecosystems.
RESTORING THE EMPTY DESERT
The world will be a poorer place if the unique biodiversity
of deserts such as the Sahara is allowed to disappear (Brito
et al., 2013). Given low human densities and that over 90%
of tropical arid and hyperarid lands remain uncultivated
(Mortimore et al., 2009), management of natural resources
in desert ecosystems may be substantially cheaper than
maintaining or restoring tropical forest habitats. Although
there is no comprehensive analysis of the causes and pat-
terns of biodiversity loss in deserts, species threat status
appears to be related to body size (Brito et al., 2013), sug-
gesting that key pressures are likely to be habitat loss or
degradation and hunting or persecution by humans (Safriel
et al., 2005).
(a)
Scimitar horned oryx
(b)
Addax
(c)
Bulbal hartebeest
(d)
Dorcas gazelle
(e)
Nubian Ibex
(f)
Barbary sheep
Figure 1 Maps of range loss for 14
species in the Sahara. The Saharan region
was defined as land where annual rainfall
was below the 250 mm isohyet (grey
shading) obtained from wordclim.org.
Historical range (thick black line) refers
to land formerly occupied by the species
prior to major anthropogenic change,
that is, prior to c. 1800. Resident range
(black shading) refers to land supporting
resident populations of a species within
the last 10 years. Note that resident
range covers areas where species are
known to occur. There are areas outside
this range where species may still occur,
but where information is lacking;
however, the extent of such areas is not
expected to significantly change the range
loss estimates in Table 1. Note also that
maps do not depict resident or historical
range outside the Sahara, although not
all species are endemic to the desert.
Small fenced reserves where populations
are not self-sustaining are not depicted
on these maps.
118 Diversity and Distributions, 20, 114–122, ª2013 John Wiley & Sons Ltd
S. M. Durant et al.
There is increasing evidence of a need for a paradigm shift
in approaches to biodiversity conservation and human devel-
opment in desert systems (Mortimore et al., 2009; IIED,
2013). Large herbivores living in deserts are nomadic and
wide-ranging, able to respond quickly to sporadic rainfall
events and to take advantage of the nutrients provided by
fresh growth (Beudels-Jamar et al., 2006). Desert-dwelling
nomadic pastoral people mimic the mobility adaptations of
the wildlife with which they share their land, enabling them
also to take advantage of variable rainfall and to exploit graz-
ing resources at the peak of their productivity (McCabe,
2004; Homewood, 2009). Unfortunately, however, there is
increasing pressure for people to settle through expanding
policies of well construction and efforts to increase agriculture
in deserts, in the mistaken belief this is the route to food secu-
rity (IIED, 2013). Such changes in land use in unpredictable
(g)
Slender horned gazelle
(h)
Cuvier’s gazelle
(i)
Dama gazelle
(j)
North African ostrich
(k)
Leopard
(l)
Saharan cheetah
(m)
African wild dog
(n)
Lion
Figure 1 Continued.
Diversity and Distributions, 20, 114–122, ª2013 John Wiley & Sons Ltd 119
Collapse of the Sahara’s megafauna
low rainfall environments have led to widespread desertifica-
tion, which have, in turn, increased the vulnerability of the
people and livestock who inhabit these systems.
Accommodating mobility of both wildlife and people
presents significant political and social challenges, particu-
larly in areas of conflict and where transboundary move-
ments are extensive, such in many areas of the Sahara.
However, surmounting these challenges and accepting that
mobility is key to efficient use of dryland resources are
essential precursors to the sustainable management of desert
ecosystems (IIED, 2013). This is also increasingly critical as
we approach an era where climate change is expected to
exacerbate drought in many regions of the globe (IPCC,
2012). While biodiversity hotspots are clearly important
and deserving of world attention, the velocity of climate
change in desert biomes is predicted to be among the fast-
est, while that in tropical forests comparatively low (Loarie
et al., 2009). Adaptation to the impacts of climate change
in deserts is thus likely to be particularly urgent. If the
neglect of desert biodiversity continues then there is a real
risk that much of their unique flora and fauna will be lost
and, along with it, some of the key information and tools
for adaptation to a warming planet.
2014 is the halfway point in the United Nations Decade
for Deserts and the Fight against Desertification and the
fourth year of the United Nations Decade for Biodiversity.
This is an opportune decade for the world’s attention to
focus on securing the sustainable management of desert eco-
systems. Such approaches need to take into account the
extreme variability in desert systems and to enshrine the
need for mobility of both people and wildlife. Governments
are committed to meet the minimum target of a zero net
rate of land degradation as agreed at Rio +20 in the UN
Convention on Sustainable Development (UNCSD, 2012). If
this goal is to be achieved, it will require the full engagement
of the scientific community. We urge scientists and conserva-
tionists to prioritize applied research into the conservation of
biodiversity and the restoration of ecosystem function in
deserts, including restocking of wildlife, so that these can
once more support their full complement of species and pro-
vide increased resilience for local human communities. There
is an urgent need for baseline information on biodiversity
trends and threats to desert ecosystems, and for research and
development of locally appropriate strategies and tools to
strengthen conservation management (Davies et al., 2012).
This will require sustained financial support and capacity
development within desert range states. However, over the
medium to long term, such investment is likely to be more
cost-effective than trying to address and reverse the ecologi-
cal and socio-economic impacts of biodiversity loss and eco-
system service degradation in a changing climate. Restoring
ecosystem function and implementing sustainable manage-
ment of desert ecosystems will not only benefit biodiversity
and some of the world’s most impoverished and marginal-
ized human communities, but will also help to mitigate
against global climate change.
ACKNOWLEDGEMENTS
We are very grateful to Eilidh Young for information about
the Darwin Initiative. We are also grateful to E Sogbohossou,
A Tehou, U Belemsobgo, P Kafando, A Ndjidda, Y Saidu,
J-B Mamang-Kanga, M Sidibe, K Nayabi, P Henschel, L
Marker, H de Iongh and G Rasmussen for their participation
in the 2012 cheetah and wild dog strategic planning work-
shop in Niger. Finally, we are grateful to the Howard G Buff-
ett Foundation, the Zoological Society of London and the
Wildlife Conservation Society for their support of the work-
shops allowing the development of the species maps.
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BIOSKETCH
Sarah M. Durant is a conservation scientist with research
interests in carnivore conservation, biodiversity monitoring,
human wildlife coexistence and conservation management.
Coauthors were participants in the ZSL desert declines work-
shop and/or the strategic planning workshop for conserva-
tion of cheetah and African wild dog in western, central and
northern Africa.
Author contributions: SMD led project development and
implementation, wrote and edited drafts of the manuscript
and coordinated manuscript submission; NP contributed to
project development and implementation, editing drafts,
workshop organization and facilitation, and produced the
figures and tables. She is senior author; TW and JN contrib-
uted to project development and implementation, editing
drafts, and assisting with mapping process; SB contributed to
editing drafts and workshop facilitation; RW contributed to
editing drafts and workshop organization; PdO and CR con-
tributed to project development and implementation, editing
drafts and workshop organization; All remaining coauthors,
listed in alphabetical order, edited drafts, attended one or
both workshops and contributed data or technical support.
Editor: David Richardson
122 Diversity and Distributions, 20, 114–122, ª2013 John Wiley & Sons Ltd
S. M. Durant et al.
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... This is the case for the Sahara-Sahel biome in northern Africa, home to over 1000 species of terrestrial vertebrates (Brito et al., 2016). Over the past decades, this important biome has been experiencing rapid changes due to increasing livestock densities, land-use changes, hunting, and social conflict (Brito et al., 2016;Durant et al., 2014), but data to assess the impacts of this changes on biodiversity trends is limited (e.g., Stabach et al., 2017). Currently, 79 vertebrate species inhabiting the Sahara-Sahel-including 23 birds-are listed on the IUCN Red List as threatened or near-threatened (Brito et al., 2016). ...
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... Gazella leptoceros is sparsely distributed throughout the Sahara Desert in northern Africa from longitude W 4°20ʹ east to the Nile River (Flower 1932;Mallon et al. 2020). Confirmed records of occurrence, collected from 2000 to 2020, are limited to Algeria, Tunisia, Libya, and Egypt ( Fig. 3; Mallon et al. 2020), with the current extent of known occurrence covering an estimated 182,005 km 2 (Durant et al. 2014). In Algeria and Tunisia, distribution of G. leptoceros closely matches the large ergs (sand seas) south of the Atlas Mountains, particularly the Grand Erg Occidental (Great Western Sand Sea) of northwestern Algeria and the Grand Erg Oriental (Great Eastern Sand Sea) that straddles the border of Algeria and Tunisia (Devillers et al. 2006;Mallon et al. 2020). ...
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Breeding programs have an essential role in the recovery of threatened populations through optimal genetic management and mating strategies. The dama gazelle ( Nanger dama ) is a North African ungulate listed as critically endangered. The mhorr subspecies is extinct in the wild and currently survives thanks to the creation in 1971 of an ex situ breeding program. The aim of the present study was to assess the evolution of genetic variability in this mhorr gazelle captive population, as well as the mating strategy used in two reference populations studied (Almeria and Europe). The entire pedigree, with 2739 animals, was analyzed to measure demographic characters, pedigree completeness level, probability of gene origin, level of relatedness and genetic structure of the population. The population size has been progressively increasing, with up to 264 individuals alive in Europe at the time of the study. The average number of equivalent complete generations was 5.55. The effective number of founders and ancestors was both 3, and the founder genome equivalent was 1.99. The genetic contributions of the four main ancestors were unbalanced. The average values of inbreeding and average relatedness for the whole pedigree were, respectively, 28.34% and 50.14%. The effective population size was 8.7 by individual increase in inbreeding and 9.8 by individual increase in coancestry. F ‐statistics evidenced a very small level of population subdivision ( F ST = 0.033370). The mating strategy used, based on the minimum coancestry of the individuals, has minimized the losses of genetic variability and helped to balance the genetic contributions between ancestors. The strategy also avoided large subdivisions within the population and the appearance of new bottlenecks. This study shows how pedigree analysis can both be used to determine the genetic variability of the population and to assess the influence of the mating strategy used in the breeding program on such variability.
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Deserts and arid regions are generally perceived as bare and rather homogeneous areas of low diversity. The Sahara is the largest warm desert in the world and together with the arid Sahel displays high topographical and climatic heterogeneity, and has experienced recent and strong climatic oscillations that have greatly shifted biodiversity distribution and community composition. The large size, remoteness and long-term political instability of the Sahara-Sahel, have limited knowledge on its biodiversity. However, over the last decade, there have been an increasing number of published scientific studies based on modern geomatic and molecular tools, and broad sampling of taxa of these regions. This review tracks trends in knowledge about biodiversity patterns, processes and threats across the Sahara-Sahel, and anticipates needs for biodiversity research and conservation. Recent studies are changing completely the perception of regional biodiversity patterns. Instead of relatively low species diversity with distribution covering most of the region, studies now suggest a high rate of endemism and larger number of species, with much narrower and fragmented ranges, frequently limited to micro-hotspots of biodiversity. Molecular-based studies are also unravelling cryptic diversity associated with mountains, which together with recent distribution atlases, allows identifying integrative biogeographic patterns in biodiversity distribution. Mapping of multivariate environmental variation (at 1 km × 1 km resolution) of the region illustrates main biogeographical features of the Sahara-Sahel and supports recently hypothesised dispersal corridors and refugia. Micro-scale water-features present mostly in mountains have been associated with local biodiversity hotspots. However, the distribution of available data on vertebrates highlights current knowledge gaps that still apply to a large proportion of the Sahara-Sahel. Current research is providing insights into key evolutionary and ecological processes, including causes and timing of radiation and divergence for multiple taxa, and associating the onset of the Sahara with diversification processes for low-mobility vertebrates. Examples of phylogeographic patterns are showing the importance of allopatric speciation in the Sahara-Sahel, and this review presents a synthetic overview of the most commonly hypothesised diversification mechanisms. Studies are also stressing that biodiversity is threatened by increasing human activities in the region, including overhunting and natural resources prospection, and in the future by predicted global warming. A representation of areas of conflict, landmines, and natural resources extraction illustrates how human activities and regional insecurity are hampering biodiversity research and conservation. Although there are still numerous knowledge gaps for the optimised conservation of biodiversity in the region, a set of research priorities is provided to identify the framework data needed to support regional conservation planning.
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