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Saving the World's Terrestrial Megafauna

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  • Biodiversity Research Institute (CSIC - Oviedo University - Principality of Asturias)

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From the late Pleistocene to the Holocene and now the so-called Anthropocene, humans have been driving an ongoing series of species declines and extinctions (Dirzo et al. 2014). Large-bodied mammals are typically at a higher risk of extinction than smaller ones (Cardillo et al. 2005). However, in some circumstances, terrestrial megafauna populations have been able to recover some of their lost numbers because of strong conservation and political commitment, as well as human cultural changes (Chapron et al. 2014). Indeed, many would be in considerably worse predicaments in the absence of conservation action (Hoffmann et al. 2015). Nevertheless, most mammalian megafauna face dramatic range contractions and population declines. In fact, 59% of the world's largest carnivores (more than or equal to 15 kilograms, n = 27) and 60% of the world's largest herbivores (more than or equal to 100 kilograms, n = 74) are classified as threatened with extinction on the International Union for the Conservation of Nature (IUCN) Red List (supplemental tables S1 and S2). This situation is particularly dire in sub-Saharan Africa and Southeast Asia, home to the greatest diversity of extant megafauna (figure 1). Species at risk of extinction include some of the world's most iconic animals—such as gorillas, rhinos, and big cats (figure 2 top row)—and, unfortunately, they are vanishing just as science is discovering their essential ecological roles (Estes et al. 2011). Here, our objectives are to raise awareness of how these megafauna are imperiled (species in tables S1 and S2) and to stimulate broad interest in developing specific recommendations and concerted action to conserve them
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Saving the World’s Terrestrial Megafauna
WILLIAM J. RIPPLE, GUILLAUME CHAPRON, JOSÉ VICENTE LÓPEZ-BAO, SARAH M. DURANT, DAVID W. MACDONALD,
PETER A. LINDSEY, ELIZABETH L. BENNETT, ROBERT L. BESCHTA, JEREMY T. BRUSKOTTER, AHIMSA CAMPOS-ARCEIZ,
RICHARD T. CORLETT, CHRIS T. DARIMONT, AMY J. DICKMAN, RODOLFO DIRZO, HOLLY T. DUBLIN, JAMES A. ESTES,
KRISTOFFER T. EVERATT, MAURO GALETTI, VARUN R. GOSWAMI, MATT W. HAYWARD, SIMON HEDGES, MICHAEL HOFFMANN,
LUKE T. B. HUNTER, GRAHAM I. H. KERLEY, MIKE LETNIC, TAAL LEVI, FIONA MAISELS, JOHN C. MORRISON,
MICHAEL PAUL NELSON, THOMAS M. NEWSOME, LUKE PAINTER, ROBERT M. PRINGLE, CHRISTOPHER J. SANDOM,
JOHN TERBORGH, ADRIAN TREVES, BLAIRE VAN VALKENBURGH, JOHN A. VUCETICH, AARON J. WIRSING,
ARIAN D. WALLACH, CHRISTOPHER WOLF, ROSIE WOODROFFE, HILLARY YOUNG, AND LI ZHANG
From the late Pleistocene to the
Holocene and now the so-called
Anthropocene, humans have been
driving an ongoing series of species
declines and extinctions (Dirzo et al.
2014). Large-bodied mammals are
typically at a higher risk of extinction
than smaller ones (Cardillo etal. 2005).
However, in some circumstances, ter-
restrial megafauna populations have
been able to recover some of their lost
numbers because of strong conserva-
tion and political commitment, as well
as human cultural changes (Chapron
et al. 2014). Indeed, many would be
in considerably worse predicaments
in the absence of conservation action
(Hoffmann etal. 2015). Nevertheless,
most mammalian megafauna face dra-
matic range contractions and popu-
lation declines. In fact, 59% of the
world’s largest carnivores (more than
or equal to 15 kilograms, n = 27) and
60% of the world’s largest herbivores
(more than or equal to 100 kilograms,
n = 74) are classified as threatened with
extinction on the International Union
for the Conservation of Nature (IUCN)
Red List (supplemental tables S1 and
S2). This situation is particularly dire
in sub-Saharan Africa and Southeast
Asia, home to the greatest diversity of
extant megafauna (figure 1). Species at
risk of extinction include some of the
world’s most iconic animals—such as
gorillas, rhinos, and big cats (figure2
top row)—and, unfortunately, they are
vanishing just as science is discov-
ering their essential ecological roles
(Estes etal. 2011). Here, our objectives
are to raise awareness of how these
megafauna are imperiled (species in
tables S1 and S2) and to stimulate
broad interest in developing specific
recommendations and concerted
action to conserve them.
Megafauna provide a range of dis-
tinct ecosystem services through top-
down biotic and knock-on abiotic
processes (Estes et al. 2011). Many
megafauna function as keystone spe-
cies and ecological engineers, gen-
erating strong cascading effects in
the ecosystems in which they occur.
These species also provide impor-
tant economic and social services.
For example, ecotourism is the fast-
est growing subsector of tourism in
developing countries (UNEP 2013),
and megafauna are a major draw for
these tourists. Besides contributing
considerable revenue to conservation,
wildlife-based tourism can contribute
significantly to education, economies,
job creation, and human livelihoods.
Many of the surviving mammalian
megafauna remain beset by long-
standing and generally escalating
threats of habitat loss, persecution,
and exploitation (Ripple et al. 2014,
2015). Large mammals are extremely
vulnerable to these threats because
of their large area requirements, low
densities (particularly for carnivores),
and relatively “slow” life-history traits
(Wallach et al. 2015). Various anthro-
pogenic forces such as deforestation,
agricultural expansion, increasing live-
stock numbers, and other forms of
human encroachment have severely
degraded critical habitat for mega-
fauna by increased fragmentation or
reduced resource availability. Although
some species show resilience by adapt-
ing to new scenarios under certain
conditions (Chapron et al. 2014),
livestock production, human popula-
tion growth, and cumulative land-use
impacts can trigger new conflicts or
exacerbate existing ones, leading to
additional declines. According to the
Food and Agriculture Organization,
as of 2014, there were an estimated 3.9
billion ruminant livestock on Earth
compared with approximately 8.5 mil-
lion individuals of 51 of the 74 spe-
cies of wild megaherbivores for which
population estimates are available
within their native ranges (table S2), a
magnitude difference of approximately
400 times.
The current depletion of mega-
fauna is also due to overhunting and
persecution: shooting, snaring, and
poisoning by humans ranging from
individuals to governments, as well as
by organized criminals and terrorists
(Darimont et al. 2015). Megafauna
are killed for meat and body parts
for traditional medicine and orna-
ments or because of actual or per-
ceived threats to humans, their crops,
or livestock. Meat and body parts are
sold locally, sold to urban markets,
or traded regionally and internation-
ally. Striking instances include the
slaughter of thousands of megafauna,
such as African elephants (Loxodonta
africana) for their ivory, rhinoceroses
for their horns, and tigers (Panthera
tigris) for their body parts. In addi-
tion, many lesser-known megafauna
species (figure 2, bottom row) are now
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Figure 1. A richness map of (a) the number of megafaunal species, (b) the number of declining megafauna species, and
(c) the number of threatened megafaunal species in their native ranges. Megafauna are defined as terrestrial large
carnivores (more than 15 kilograms) and large herbivores (more than 100 kilograms). Threatened includes all species
categorized as Vulnerable, Endangered, or Critically Endangered on the IUCN Red List (see supplemental tables).
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declined markedly in many protected
areas (IUCN 2015).
Although many of the general
causes and mechanisms of declines
are well identified and recognized, this
understanding has not translated into
adequate conservation action. Some
of the existing mammal-prioritiza-
tion schemes could be incorporated
into a comprehensive global strategy
for conserving the largest mammals
(Rondinini etal. 2011). Increasing pri-
oritization and political will to conserve
megafauna—and actions to restore
or reintroduce them in areas where
they have declined or been extirpated
(such as plans to reintroduce scimitar-
horned oryx into Chad and to rehabili-
tate the entire Gorongosa ecosystem in
Mozambique)—are urgently needed.
We suggest that the problem has two
(IUCN 2015). The Sumatran rhino
(Dicerorhinus sumatrensis) is already
extinct in the wild in Malaysia and is
very close to extinction in Indonesia,
with the population collapsing during
the last 30 years from over 800 to fewer
than 100 (table S2). The Javan rhino
(Rhinoceros sondaicus) is down to a
single population of approximately
58 in a single reserve (table S2). The
Critically Endangered Bactrian camel
(Camelus ferus) and African wild ass
(Equus africanus) are not far behind.
Even in protected areas, megafauna
are increasingly under assault. For
example, in West and Central Africa,
several large carnivores (including
lions, Panthera leo; African wild dogs,
Lycaon pictus; and cheetahs, Acinonyx
jubatus) have experienced recent
severe range contractions and have
imperiled (tables S1 and S2). Most
of the world’s megaherbivores remain
poorly studied, and this knowledge
gap makes conserving them even more
difficult (Ripple etal. 2015).
Under a business-as-usual scenario,
conservation scientists will soon be
busy writing obituaries for species and
subspecies of megafauna as they vanish
from the planet. In fact, this process is
already underway: eulogies have been
written for Africa’s western black rhi-
noceros (Diceros bicornis longipes) and
the Vietnamese subspecies of the Javan
rhinoceros (Rhinoceros sondaicus
annamiticus, IUCN 2015). Epitaphs
will probably soon be needed for the
kouprey (Bos sauveli), last seen in
1988; and the northern white rhinoc-
eros (Ceratotherium simum cottoni),
which now numbers three individuals
Figure 2. Photographic examples of threatened megafauna. Top row left to right: photos of well-known species, including
the Western gorilla (Gorilla gorilla) (CR), black rhino (Diceros bicornis) (CR), and Bengal tiger, (Panthera tigris tigris)
(EN). Bottom row left to right: photos of lesser-known species, including the African wild ass (Equus africanus) (CR),
Visayan warty pig (Sus cebifrons) (CR), and banteng (Bos javanicus) (EN). Photo credits: Julio Yeste, Four Oaks, Dave M.
Hunt, Mikhail Blajenov, KMW Photography, and Kajornyot.
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Convention on International Trade in
Endangered Species of Wild Fauna and
Flora (CITES) have had some success
in safeguarding species. However, the
decisions of these conventions are not
always binding, and they will require
substantially increased political will
and financial support if they are to be
effective in the critical task of securing
the survival of the world’s megafauna.
Some regional instruments such as
the CMS Gorilla Agreement and the
Global Tiger Initiative incorporate
environmental or biodiversity commit-
ments and are playing a growing role in
protecting biodiversity. International
agreements are often well placed for
enforcing regional frameworks for
megafauna; examples include the
responsibility as scientists who study
megafauna to act to prevent their
decline. We therefore present a call
to the broader international commu-
nity to join together in conserving
the remaining terrestrial megafauna
(see declaration in box 1).
From declaration to action
Social and political commitment to
provide sufficient protection across
the vast landscapes needed for the
conservation of the world’s megafauna
is increasingly required. International
frameworks and conventions such
as the Convention on Biological
Diversity (CBD), the Convention on
the Conservation of Migratory Species
of Wild Animals (CMS), and the
parts: (1) a need to further and more
effectively implement, expand, and
refine current interventions at relevant
scales and (2) a need for large-scale
policy shifts and global increases in
funding for conservation to alter the
framework and ways in which people
interact with wildlife.
In order to save declining species,
there is a need to increase global
conservation funding by at least
an order of magnitude (McCarthy
et al. 2012). Without such a trans-
formation, there is a risk that many
of the world’s most iconic species
may not survive to the twenty-sec-
ond century. We must not go qui-
etly into this impoverished future.
Rather, we believe it is our collective
Box 1. A declaration to save the world’s terrestrial megafauna.
We conservation scientists
1. Acknowledge that most of the terrestrial megafauna species are threatened with extinction and have declining populations. Some
megafauna species that are not globally threatened nonetheless face local extinctions or have Critically Endangered subspecies.
2. Appreciate that “business as usual” will result in the loss of many of the Earth’s most iconic species.
3. Understand that megafauna have ecological roles that directly and indirectly affect ecosystem processes and other species through-
out the food web; failure to reverse megafaunal declines will disrupt species interactions, with negative consequences for ecosystem
function; biological diversity; and the ecological, economic, and social services that these species provide.
4. Realize that megafauna are epitomized as a symbol of the wilderness, exemplifying the public’s engagement in nature, and that this
is a driving force behind efforts to maintain the ecosystem services they can provide.
5. Recognize the importance of integrating and better aligning human development and biodiversity conservation needs through the
engagement and support of local communities in developing countries.
6. Propose that funding agencies and scientists increase conservation research efforts in developing countries, where most threatened
megafauna occur. Specifically, there is a need to increase the amount of research directed at finding solutions for the conservation
of megafauna, especially for lesser-known species.
7. Request the help of individuals, governments, corporations, and nongovernmental organizations to stop practices that are harmful
to these species and to actively engage in helping to reverse declines in megafauna.
8. Strive for increased awareness among the global public of the current megafauna crisis using traditional media as well as social
media and other networking approaches.
9. Seek a new and comprehensive global commitment and framework for conserving megafauna. The international community
should take necessary action to prevent mass extinction of the world’s megafauna and other species.
10. Urge the development of new funding mechanisms to transfer the current benefits accrued through the existence values of mega-
fauna into tangible payments to support research, conservation actions, and local people who bear the cost of living with wildlife
in the places where highly valued megafauna must be preserved.
11. Advocate for interdisciplinary scientific interchange between nations to improve the social and ecological understanding of the
drivers of the decline of megafauna and to increase the capacity for megafauna science and conservation.
12. Recommend the reintroduction and rehabilitation, following accepted IUCN guidelines, of degraded megafauna populations
whenever possible, the ecological and economic importance of which is evidenced by a growing number of success stories, from
Yellowstone’s wolves (Canis lupus) and the Père David’s deer (Elaphurus davidianus) in China to the various megafauna species of
Gorongosa National Park in Mozambique.
13. Affirm an abiding moral obligation to protect the Earth’s megafauna.
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William J. Ripple (bill.ripple@oregonstate.edu),
Robert L. Beschta, Michael Paul Nelson,
Luke Painter Christopher Wolf, and Thomas
M. Newsome are affiliated with the Global
Trophic Cascades Program of the Department of
Forest Ecosystems and Society at Oregon State
University, in Corvallis; TMN is also with the
Desert Ecology Research Group of the School of
Biological Sciences at the University of Sydney,
in Australia; the Centre for Integrative Ecology
at the School of Life and Environmental Sciences
at Deakin University, in Geelong, Australia;
and the School of Environmental and Forest
Sciences, at the University of Washington, in
Seattle. Guillaume Chapron is affiliated with the
Department of Ecology at the Swedish University
of Agricultural Sciences, in Riddarhyttan.
José Vicente López-Bao is with the Research
Unit of Biodiversity at Oviedo University, in
Mieres, Spain. Sarah M. Durant and Rosie
Woodroffe are with the Institute of Zoology at
the Zoological Society of London, Regents Park.
David W. Macdonald and Amy J. Dickman are
with the Wildlife Conservation Research Unit
of the Department of Zoology at the University
of Oxford and the Recanati-Kaplan Centre, in
Abingdon, United Kingdom. Peter A. Lindsey and
Luke T. B. Hunter are affiliated with Panthera,
in New York. PAL is also affiliated with the
Mammal Research Institute of the Department
of Zoology and Entomology at the University of
Pretoria, in Gauteng, South Africa ; and LTBH
is also affiliated with the School of Life Sciences
at the University of KwaZulu-Natal in Durban,
South Africa. Elizabeth L. Bennett, Simon
Hedges, and Fiona Maisels are affiliated with
the Wildlife Conservation Society, in New York;
FM is also with the School of Natural Sciences
at the University of Stirling, in the United
Kingdom. Holly T. Dublin is affiliated with
IUCN Species Survival Commission’s African
Elephant Specialist Group at the IUCN Eastern
and Southern African Regional Office in Nairobi,
Kenya. Jeremy T. Bruskotter is affiliated with the
School of Environment and Natural Resources
at The Ohio State University, in Columbus.
Ahimsa Campos-Arceiz is with the School of
Geography at the University of Nottingham
Malaysia Campus. Richard T. Corlett is affiliated
with the Center for Integrative Conservation of
the Xishuangbanna Tropical Botanical Garden
at the Chinese Academy of Sciences, in Menglun,
Yunnan, China. Chris T. Darimont is with the
Department of Geography at the University
of Victoria and the Raincoast Conservation
Foundation, in British Columbia, Canada.
Rodolfo Dirzo is affiliated with the Department
of Biology at Stanford University, in California.
James A. Estes is with the Department of Ecology
and Evolutionary Biology at the University of
California, in Santa Cruz. Kristoffer T. Everatt,
Matt W. Hayward, and Graham I. H. Kerley
are affiliated with the Centre for African
Conservation Ecology at Nelson Mandela
University, in Port Elizabeth, South Africa;
MWH is also with the School of Biological
six other languages: Spanish, Chinese,
French, Portuguese, Malay (Bahasa
Malaysia), and Thai.
Acknowledgments
We thank L. West for work on the esti-
mated population sizes in the supple-
mental appendices.
Supplemental material
The supplemental material is available
online at http://bioscience.oxfordjourn-
als.org/lookup/suppl/doi:10.1093/biosci/
biw092/-/DC1.
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an extinction process that appears to
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Supplementary resource (1)

... The world now recognizes that human activities have placed many iconic species in a precarious state (Ripple et al., 2016). Taking action to safeguard them and their habitat has been at the forefront of conservation science since the 1980s. ...
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... As human populations grow and natural habitat shrinks, carnivores and humans overlap spatially resulting in more conflict over space and resource use (Ripple et al. 2016). Human-carnivore conflict (HCC) has been a threat to biodiversity conservation, and the need to develop good conservation methods for coexistence is vitally important on one hand for maintaining viable carnivore populations, but on the other hand for improving livestock security, local livelihoods and safety Dickman 2010;LeFlore et al. 2019;Ogada et al. 2003). ...
... Biodiversity declines are particularly evident among global populations of large-bodied "megafauna" (i.e. mammal species >100 kg of body mass) (Ripple et al. 2016) of both herbivorous (Ripple et al. 2015) and carnivorous species (Ripple et al. 2014). East Africa is no exception to this worrisome global pattern. ...
Chapter
For millennia, people have lived alongside wildlife in the semi-arid savanna of the Tarangire Ecosystem (TE), northern Tanzania. The TE preserves one of the last long-distance wildlife migrations in Africa as well as a large and diverse human population. Initial wildlife conservation approaches, settlement politics, and changes in human livelihoods have created a fragmented coupled social-ecological system that currently faces serious challenges for both people and wildlife. In this introduction to the book “Tarangire: Human-Wildlife Coexistence in a Fragmented Ecosystem” we outline the environmental and climatic settings as well as the social, economic, and political structures and histories of the ecosystem. The combination of heterogeneous geology, variable rainfall, a historical focus on conserving dry-season ranges of wildlife, and an expanding human population brings people and wildlife in contact, often with negative consequences for humans and wildlife. From an anthropocentric perspective, large carnivores and elephants are perceived as particularly problematic. In this book, we adopt a social-ecological approach and present different perspectives on wildlife conservation in the TE as frameworks for integrated and effective solutions. The first section of the book addresses the human dimension in human-wildlife interactions, whereas the second section employs a more ecocentric perspective and summarizes the status and ecologies of key large-mammal populations in the TE. The third section addresses human-wildlife interactions explicitly with an eye towards solutions.
... Terrestrial mammals, especially large species, are usually of socioeconomic importance, so effective management of their populations is a matter of special concern, one which in the human-dominated landscape poses a considerable challenge (König et al., 2020;Linnell et al., 2020;Ripple et al., 2016). Since beavers facilitate the occurrence of larger numbers of mammal species and are active within a restricted area, our study highlights the potential role of beavers in landscape planning and management. ...
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There is increasing awareness of the ecosystem engineering services provided by recovering populations of Eurasian beaver. By modifying aquatic environments, this species has a significant, positive influence on biodiversity. Beaver activity affects not only aquatic ecosystems but also terrestrial habitats and organisms. Our study compares and evaluates the species richness and activity of terrestrial mammals in winter at beaver ponds (N = 65) and randomly-selected reference sites along nearby watercourses unmodified by beavers (N = 65) in Poland (central Europe). Mammal assemblages were investigated near pond/watercourse edges, and also at some distance from them. The species richness of mammal and numbers of their tracks were respectively 25% and 33% greater on the beaver than on the reference sites. The higher species richness on beaver sites extended to areas 40–60 m distant from ponds, devoid any signs of beaver activity. Twenty-three mammal species were recorded on beaver sites (mean species richness 3.8 ± 1.6 SD), and 20 on reference ones (3.0 ± 1.5 SD). The numbers of tracks of grey wolf, least weasel and European polecat were higher on beaver than reference sites. Mammal species richness and activity were related to the existence of beaver ponds, but were also correlated with the numbers of snags and coverage of grass, bramble and coniferous saplings in neighbouring terrestrial habitats. Large and small carnivores occurred more frequently and were more active on beaver sites. The frequencies of occurrence of mesocarnivores, mesoherbivores and small herbivores were correlated with habitat characteristics, regardless of whether beavers were present or not. Our results highlight the fact that both pond creation and the habitat changes resulting from the presence of beavers rearrange the occurrence and activity of the terrestrial mammal assemblage.
... As these roles are often near the top of trophic systems, large carnivores can be key ecological regulators facilitating the maintenance of ecosystem health (Estes et al., 2011;Ripple et al., 2014). Despite their ecological importance, >75% of the world's remaining large carnivore populations have declining trajectories (Ripple et al., 2014(Ripple et al., , 2016Wolf and Ripple, 2017) principally driven by habitat loss and fragmentation, overhunting, prey depletion, and conflict with humans (Dickman, 2010;Ripple et al., 2014;Eklund et al., 2017;Wolf and Ripple, 2017;Krafte Holland et al., 2018). Conflict between humans and carnivores tends to be associated with threats to human security and private property (Ripple et al., 2014;van Eeden et al., 2018a,b). ...
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Carnivore depredation of livestock is one of the primary drivers of human-carnivore conflict globally, threatening the well-being of livestock owners, and fueling large carnivore population declines. Interventions designed to reduce carnivore depredation typically center around predictions of depredation risk. However, these spatial risk models tend to be informed by data depicting the number of livestock attacked by carnivores. Importantly, such models omit key stages in the predation sequence which are required to predict predation risk, or in this case depredation risk. Applying the classic predation risk model defined by Lima and Dill demonstrates that depredation risk is dependent upon quantifying the rates at which carnivores encounter livestock before attacking. However, encounter rate is challenging to estimate, necessitating novel data collection systems. We developed and applied such a system to quantify carnivore-livestock encounters at livestock corrals (i.e., bomas) across a 9-month period in Central Kenya. Concurrently, we monitored the number of livestock attacked by carnivores at these bomas. We calculated carnivore-livestock encounter rates, attack rates, and depredation risk at the boma. We detected 1,383 instances in which carnivores encountered livestock at the bomas. However, we only recorded seven attacks. We found that the encounter rate and attack rate for spotted hyenas were almost six and three times higher than that for any other species, respectively. Consequently, spotted hyenas posed the greatest depredation risk for livestock at the boma. We argue that better understanding of carnivore-livestock encounter rates is necessary for effective prediction and mitigation of carnivore depredation of livestock.
... Through opposing bottom-up forces, primary productivity can regulate consumer population abundance and in turn, their predators (Caughley, 1976;Sinclair, 1977;Houston, 1982). Evidence of trophic cascades following predator reintroductions has fostered support for conservation of large carnivores as agents improving biodiversity (Miller et al., 2001;Beschta, 2004, 2012;Estes, 2005;Schmitz, 2006;Ripple et al., 2014Ripple et al., , 2016. Conversely, predators' top-down effects on ungulate populations are used as support for controversial predator control activities (Boertje et al., 1996;Titus, 2007). ...
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As climate change accelerates in northern latitudes, there is an increasing need to understand the role of climate in influencing predator-prey systems. We investigated wolf population dynamics and numerical response in Denali National Park and Preserve in Alaska, United States from 1986 to 2016 under a long-term range of varying climatic conditions and in the context of prey vulnerability, abundance, and population structure using an integrated population modeling approach. We found that wolf natality, or the number of wolves added to packs, increased with higher caribou population size, calf:cow ratio, and hare numbers, responding to a 1-year lag. Apparent survival increased in years with higher calf:cow ratios and cumulative snowfall in the prior winter, indicators of a vulnerable prey base. Thus, indices of prey abundance and vulnerability led to responses in wolf demographics, but we did not find that the wolf population responded numerically. During recent caribou and moose population increases wolf natality increased yet wolf population size declined. The decline in wolf population size is attributed to fewer packs in recent years with a few very large packs as opposed to several packs of comparable size. Our results suggest that territoriality can play a vital role in our study area on regulating population growth. These results provide a baseline comparison of wolf responses to climatic and prey variability in an area with relatively low levels of human disturbance, a rare feature in wolf habitat worldwide.
... As a result, most terrestrial large mammal migrations are in sharp decline or already extinct [13,14]. Moreover, protected areas tend to concentrate human population density at their edges [10,15], restricting animal mobility and leading to increased humanwildlife conflict, including increased incidences of poaching, and competition and/or predation of livestock [4,10,[16][17][18]. Finding solutions that ensure the coexistence of wildlife with humans, especially across areas with no form of environmental protection, is crucial for the future of conservation of these species [5,17]. ...
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Understanding how wildlife interacts with human activities across non-protected areas are critical for conservation. This is especially true for ungulates that inhabit human-dominated landscapes outside the protected area system in Nepal, where wildlife often coexists with livestock. Here we investigated how elevation, agricultural land, distance from roads, and the relative abundance of livestock (goats, sheep, cow and buffalo) influenced wild ungulate chital (Axis axis), nilgai (Boselaphustrago camelus), wild boar (Sus scrofa) and sambar (Rusa unicolor) abundance and occurrence. We counted all individuals of wild ungulates and livestock along 35 transects conducted between November 2017 and March 2018 in community forests of Bara and Rautahat distracts in the lowlands of Nepal. We assessed abundance and occurrence relation to covariates using Generalized Linear Models. We found that livestock outnumbered wild ungulates 6.6 to 1. Wild boar was the most abundant wild ungulate, followed by nilgai, chital, and sambar. Elevation and livestock abundance were the most important covariates affecting the overall abundance of wild ungulates and the distribution of each individual ungulate species. Our results suggest spatial segregation between wild ungulates, which occur mainly on high grounds (> 300 m.a.s.l.), and livestock that concentrate across low ground habitats (< 300 m.a.s.l.). Our results provide a critical first step to inform conservation in community forest areas of Nepal, where wildlife interacts with people and their livestock. Finding better strategies to allow the coexistence of ungu-lates with people and their livestock is imperative if they are to persist into the future.
... Yet, a substantial proportion of the distributional range of Africa's large carnivores [e.g., 78% of cheetah Acinonyx jubatus (Durant et al., 2017) and 83% of leopard Panthera pardus (Jacobson et al., 2016)] is outside current protected areas in mixed-use landscapes. Outside protected areas large carnivores face increasing and multiple threats, including conflicts due to livestock depredation, loss of prey and habitat, and land degradation and fragmentation (Ripple et al., 2016). However, large carnivore presence also indicates alternative possibilities for the management of multiple-use landscapes, if wildlife can provide value to local communities. ...
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Coexistence with large carnivores poses challenges to human well-being, livelihoods, development, resource management, and policy. Even where people and carnivores have historically coexisted, traditional patterns of behavior toward large carnivores may be disrupted by wider processes of economic, social, political, and climate change. Conservation interventions have typically focused on changing behaviors of those living alongside large carnivores to promote sustainable practices. While these interventions remain important, their success is inextricably linked to broader socio-political contexts, including natural resource governance and equitable distribution of conservation-linked costs and benefits. In this context we propose a Theory of Change to identify logical pathways of action through which coexistence with large carnivores can be enhanced. We focus on Africa's dryland landscapes, known for their diverse guild of large carnivores that remain relatively widespread across the continent. We review the literature to understand coexistence and its challenges; explain our Theory of Change, including expected outcomes and pathways to impact; and discuss how our model could be implemented and operationalized. Our analysis draws on the experience of coauthors, who are scientists and practitioners, and on literature from conservation, political ecology, and anthropology to explore the challenges, local realities, and place-based conditions under which expected outcomes succeed or fail. Three pathways to impact were identified: (a) putting in place good governance harmonized across geographic scales; (b) addressing coexistence at the landscape level; and (c) reducing costs and increasing benefits of sharing a landscape with large carnivores. Coordinated conservation across the extensive, and potentially transboundary, landscapes needed by large carnivores requires harmonization of top-down approaches with bottom-up community-based conservation. We propose adaptive co-management approaches combined with processes for active community engagement and informed consent as useful dynamic mechanisms for navigating through this contested space, while enabling adaptation to climate change. Success depends on strengthening underlying enabling conditions, including governance, capacity, local empowerment, effective monitoring, and sustainable financial support. Implementing the Theory of Change requires ongoing monitoring and evaluation to inform adaptation and build confidence in the model. Overall, the model provides a flexible and practical framework that can be adapted to dynamic local socio-ecological contexts.
... We selected this group for three reasons. First, habitat loss and fragmentation tend to have strongly detrimental effects on this taxon due the slow life history traits and greater habitat area requirements [44,45]. Second, these species are heavily impacted by conflict with humans, either through direct mortality, or via human hunting of their prey base [46,47]. ...
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Protected areas (PAs) constitute one of the main tools for global landscape conservation. Recently, payments for environmental services (PES) have attracted interest from national and regional governments and are becoming one of the leading conservation policy instruments in tropical countries. However, the degree to which areas designated for PES overlap with areas that are critical for maintaining species’ landscape connectivity is rarely evaluated. We estimated habitat distributions and connectivity for 16 of the 22 mammalian carnivores occurring in the Caribbean region of Colombia, and identified the overlap between existing PAs and areas identified as being important for connectivity for these species. We also evaluated the potential impact of creation of new PAs versus new PES areas on conserving connectivity for carnivores. Our results show that PAs cover only a minor percentage of the total area that is important for maintaining connectivity (x ¼ 26:8% + 20:2 s:d:). On the other hand, PES, if implemented extensively, could contribute substantially to mammalian carnivores’ connectivity (x ¼ 45:4% + 12:8 s:d:). However, in a more realistic scenario with limited conservation investment in which fewer areas are set aside, a strategy based on implementing new PAs seems superior to PES. We argue that prioritizing designation of new PAs will be the most efficient means through which to maintain connectivity
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In a conservation setting where escalating tension has been the norm, the unarmed primarily female-composed Black Mambas Anti-Poaching Unit (BMAPU) in South Africa are a successful counterpoint in that they have decimated poaching using only diplomacy and patrols. We sought to understand if the BMAPU is achieving its secondary goal of influencing support for conservation and wildlife among the nearby populace via community-based conservation actions including outreach and environmental education. We also determined the impact that the program has on the Mambas themselves. Using a mixed-methods survey we conducted structured in-person interviews with 120 community members from four communities where the women of the BMAPU live, and among all the women that were on active duty in the BMAPU at the time of the surveys. We found that all participants in the BMAPU program reported improved self and community perception of their societal role as financial providers, as well as their sense of agency and self-efficacy, relative to before becoming rangers. We also found that having BMAPU rangers living in the communities by itself did not contribute to community-level support for wildlife conservation or protected areas. However, one community with both a large-scale children's conservation education program and an equitable distribution of financial benefits paid by the nearby conservation concessionaires was significantly more supportive of wildlife conservation and protected areas than the other three. Further research to parse the relative contributions of the two contributing factors of education and financial benefit would help clarify their relative contributions. From this study, we conclude that a combination of child-focused conservation education programs and equitable distribution of financial benefits leads to increased community support for wildlife, conservation, and protected natural areas, and decreases support for poaching.
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Large wild herbivores are crucial to ecosystems and human societies. We highlight the 74 largest terrestrial herbi-vore species on Earth (body mass > – 100 kg), the threats they face, their important and often overlooked ecosystem effects, and the conservation efforts needed to save them and their predators from extinction. Large herbivores are generally facing dramatic population declines and range contractions, such that ~60% are threatened with extinction. Nearly all threatened species are in developing countries, where major threats include hunting, land-use change, and resource depression by livestock. Loss of large herbivores can have cascading effects on other species including large carnivores, scavengers, mesoherbivores, small mammals, and ecological processes involving vegetation , hydrology, nutrient cycling, and fire regimes. The rate of large herbivore decline suggests that ever-larger swaths of the world will soon lack many of the vital ecological services these animals provide, resulting in enormous ecological and social costs.
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Previous studies show that conservation actions have prevented extinctions, recovered populations, and reduced declining trends in global biodiversity. However, all studies to date have substantially underestimated the difference conservation action makes because they failed to account fully for what would have happened in the absence thereof. We undertook a scenario-based thought experiment to better quantify the effect conservation actions have had on the extinction risk of the world's 235 recognized ungulate species. We did so by comparing species' observed conservation status in 2008 with their estimated status under counterfactual scenarios in which conservation efforts ceased in 1996. We estimated that without conservation at least 148 species would have deteriorated by one International Union for Conservation of Nature (IUCN) Red List category, including 6 species that now would be listed as extinct or extinct in the wild. The overall decline in the conservation status of ungulates would have been nearly 8 times worse than observed. This trend would have been greater still if not for conservation on private lands. While some species have benefited from highly targeted interventions, such as reintroduction, most benefited collaterally from conservation such as habitat protection. We found that the difference conservation action makes to the conservation status of the world's ungulate species is likely to be higher than previously estimated. Increased, and sustained, investment could help achieve further improvements. © 2015 The Authors. Conservation Biology published by Wiley Periodicals, Inc., on behalf of Society for Conservation Biology.
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Large ‘apex’ predators influence ecosystems in profound ways, by limiting the density of their prey and controlling smaller ‘mesopredators’. The loss of apex predators from much of their range has lead to a global outbreak of mesopredators, a process known as ‘mesopredator release’ that increases predation pressure and diminishes biodiversity. While the classifications apex- and meso-predator are fundamental to current ecological thinking, their definition has remained ambiguous. Trophic cascades theory has shown the importance of predation as a limit to population size for a variety of taxa (top–down control). The largest of predators however are unlikely to be limited in this fashion, and their densities are commonly assumed to be determined by the availability of their prey (bottom–up control). However, bottom–up regulation of apex predators is contradicted by many studies, particularly of non-hunted populations. We offer an alternative view that apex predators are distinguishable by a capacity to limit their own population densities (self-regulation). We tested this idea using a set of life-history traits that could contribute to self-regulation in the Carnivora, and found that an upper limit body mass of 34 kg (corresponding with an average mass of 13–16 kg) marks a transition between extrinsically- and self-regulated carnivores. Small carnivores share fast reproductive rates and development and higher densities. Large carnivores share slow reproductive rates and development, extended parental care, sparsely populated territories, and a propensity towards infanticide, reproductive suppression, alloparental care and cooperative hunting. We discuss how the expression of traits that contribute to self-regulation (e.g. reproductive suppression) depends on social stability, and highlight the importance of studying predator–prey dynamics in the absence of predator persecution. Self-regulation in large carnivores may ensure that the largest and the fiercest do not overexploit their resources.
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The conservation of large carnivores is a formidable challenge for biodiversity conservation. Using a data set on the past and current status of brown bears (Ursus arctos), Eurasian lynx (Lynx lynx), gray wolves (Canis lupus), and wolverines (Gulo gulo) in European countries, we show that roughly one-third of mainland Europe hosts at least one large carnivore species, with stable or increasing abundance in most cases in 21st-century records. The reasons for this overall conservation success include protective legislation, supportive public opinion, and a variety of practices making coexistence between large carnivores and people possible. The European situation reveals that large carnivores and people can share the same landscape.
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We live amid a global wave of anthropogenically driven biodiversity loss: species and population extirpations and, critically, declines in local species abundance. Particularly, human impacts on animal biodiversity are an under-recognized form of global environmental change. Among terrestrial vertebrates, 322 species have become extinct since 1500, and populations of the remaining species show 25% average decline in abundance. Invertebrate patterns are equally dire: 67% of monitored populations show 45% mean abundance decline. Such animal declines will cascade onto ecosystem functioning and human well-being. Much remains unknown about this “Anthropocene defaunation”; these knowledge gaps hinder our capacity to predict and limit defaunation impacts. Clearly, however, defaunation is both a pervasive component of the planet’s sixth mass extinction and also a major driver of global ecological change.
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Large carnivores face serious threats and are experiencing massive declines in their populations and geographic ranges around the world. We highlight how these threats have affected the conservation status and ecological functioning of the 31 largest mammalian carnivores on Earth. Consistent with theory, empirical studies increasingly show that large carnivores have substantial effects on the structure and function of diverse ecosystems. Significant cascading trophic interactions, mediated by their prey or sympatric mesopredators, arise when some of these carnivores are extirpated from or repatriated to ecosystems. Unexpected effects of trophic cascades on various taxa and processes include changes to bird, mammal, invertebrate, and herpetofauna abundance or richness; subsidies to scavengers; altered disease dynamics; carbon sequestration; modified stream morphology; and crop damage. Promoting tolerance and coexistence with large carnivores is a crucial societal challenge that will ultimately determine the fate of Earth’s largest carnivores and all that depends upon them, including humans.
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The huge conservation interest that mammals attract and the large datasets that have been collected on them have propelled a diversity of global mammal prioritization schemes, but no comprehensive global mammal conservation strategy. We highlight some of the potential discrepancies between the schemes presented in this theme issue, including: conservation of species or areas, reactive and proactive conservation approaches, conservation knowledge and action, levels of aggregation of indicators of trend and scale issues. We propose that recently collected global mammal data and many of the mammal prioritization schemes now available could be incorporated into a comprehensive global strategy for the conservation of mammals. The task of developing such a strategy should be coordinated by a super-partes, authoritative institution (e.g. the International Union for Conservation of Nature, IUCN). The strategy would facilitate funding agencies, conservation organizations and national institutions to rapidly identify a number of short-term and long-term global conservation priorities, and act complementarily to achieve them.
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Until recently, large apex consumers were ubiquitous across the globe and had been for millions of years. The loss of these animals may be humankind’s most pervasive influence on nature. Although such losses are widely viewed as an ethical and aesthetic problem, recent research reveals extensive cascading effects of their disappearance in marine, terrestrial, and freshwater ecosystems worldwide. This empirical work supports long-standing theory about the role of top-down forcing in ecosystems but also highlights the unanticipated impacts of trophic cascades on processes as diverse as the dynamics of disease, wildfire, carbon sequestration, invasive species, and biogeochemical cycles. These findings emphasize the urgent need for interdisciplinary research to forecast the effects of trophic downgrading on process, function, and resilience in global ecosystems.
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Paradigms of sustainable exploitation focus on population dynamics of prey and yields to humanity but ignore the behavior of humans as predators. We compared patterns of predation by contemporary hunters and fishers with those of other predators that compete over shared prey (terrestrial mammals and marine fishes). Our global survey (2125 estimates of annual finite exploitation rate) revealed that humans kill adult prey, the reproductive capital of populations, at much higher median rates than other predators (up to 14 times higher), with particularly intense exploitation of terrestrial carnivores and fishes. Given this competitive dominance, impacts on predators, and other unique predatory behavior, we suggest that humans function as an unsustainable "super predator," which—unless additionally constrained by managers—will continue to alter ecological and evolutionary processes globally. Copyright © 2015, American Association for the Advancement of Science.
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World governments have committed to halting human-induced extinctions and safeguarding important sites for biodiversity by 2020, but the financial costs of meeting these targets are largely unknown. We estimate the cost of reducing the extinction risk of all globally threatened bird species (by ≥1 International Union for Conservation of Nature Red List category) to be U.S. $0.875 to $1.23 billion annually over the next decade, of which 12% is currently funded. Incorporating threatened nonavian species increases this total to U.S. $3.41 to $4.76 billion annually. We estimate that protecting and effectively managing all terrestrial sites of global avian conservation significance (11,731 Important Bird Areas) would cost U.S. $65.1 billion annually. Adding sites for other taxa increases this to U.S. $76.1 billion annually. Meeting these targets will require conservation funding to increase by at least an order of magnitude.