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Abstract

Global conservation policy must stop the disappearance of Earth's few intact ecosystems
OBITUARY Thomas Steitz,
ribosome Nobel laureate,
remembered p.36
CORRESPONDENCE Staff at the FAO
can advise on data analysis
and interpretation p.35
HISTORY How the CIA
co-opted science in
the cold war p.32
ECOLOGY Domestic safari finds
rich biodiversity down the
back of the sofa p.31
Protect the last of the wild
Global conservation policy must stop the disappearance of Earth’s few intact
ecosystems, warn James E. M. Watson, James R. Allan and colleagues.
A
century ago, only 15% of Earth’s
surface was used to grow crops and
raise livestock1. Today, more than
77% of land (excluding Antarctica) and
87% of the ocean has been modified by the
direct effects of human activities
2,3
. This is
illustrated in our global map of intact eco-
systems (see ‘What’s left?’).
Between 1993 and 2009, an area of terres-
trial wilderness larger than India — a stag-
gering 3.3million square kilometres — was
lost to human settlement, farming, mining
and other pressures4. In the ocean, areas that
are free of industrial fishing, pollution and
shipping are almost completely confined to
the polar regions5.
Numerous studies are revealing that
Earth’s remaining wilderness areas are
increasingly important buffers against the
effects of climate change and other human
impacts. But, so far, the contribution of
intact ecosystems has not been an explicit
target in any international policy framework,
such as the United Nations’ Strategic Plan for
Biodiversity or the Paris climate agreement.
This must change if we are to prevent
Earth’s intact ecosystems from disappear-
ing completely.
LAST CHANCE
In 2016, we led an international team of
scientists to map the worlds remaining
terrestrial wilderness
3,4
. This year, we pro-
duced a similar map for intact ocean eco-
systems2 (see ‘Wild Earth’). The results of
these efforts show that time is running out
to safeguard the health of the planet — and
human well-being.
Some conservationists contend that
A Xikrin woman walks back to her village from the Cateté River in Brazil.
TAYLOR WEIDMAN/ZREPORTAGE.COM/ZUMA
1 NOVEMBER 2018 | VOL 563 | NATURE | 27
COMMENT
particular areas in fragmented and
otherwise-degraded ecosystems are more
important than undisturbed ecosystems
6,7
.
Fragmented areas might provide key ser-
vices, such as tourism revenue and benefits
to human health, or be rich in threatened
biodiversity. Yet numerous studies are start-
ing to reveal that Earths most intact eco-
systems have all sorts of functions that are
becoming increasingly crucial2,8,9.
Wilderness areas are now the only places
that contain mixes of species at near-natural
levels of abundance. They are also the only
areas supporting the ecological processes
that sustain biodiversity over evolution-
ary timescales10. As such, they are impor-
tant reservoirs of genetic information, and
act as reference areas for efforts to re-wild
degraded land and seascapes.
Various analyses reveal that wilderness
areas provide increasingly important ref-
uges for species that are declining in land-
scapes dominated by people
11
. In the seas,
they are the last regions that still contain
viable populations of top predators, such as
tuna, marlins and sharks9.
Safeguarding intact ecosystems is also key
to mitigating the effects of climate change,
which are making the refuge function of
wilderness areas especially important. A
2009 study, for instance, showed that Car-
ibbean coral reefs that have low levels of
pollution or fishing pressure recovered from
coral bleaching up to four times faster than
did reefs with high levels of both12. And a
2012 global meta-analysis revealed that the
impacts of climate change on ecological
communities are more severe in fragmented
landscapes13.
Many wilderness areas are critical
sinks for atmospheric carbon dioxide.
For example, the boreal forest is the most
intact ecosystem on the planet and holds
one-third of the worlds terrestrial carbon.
And intact forested ecosystems are able to
store and sequester much more carbon than
are degraded ones
8
. In the tropics, logging
and burning now accounts for up to 40%
of total above-ground carbon emissions
14
.
In the ocean, seagrass meadows that are
degraded (such as by sediment pollution)
switch from being carbon sinks to major
carbon sources15.
Moreover, models based on geography,
rainfall, degree of deforestation and so on
are starting to reveal the degree to which
wilderness areas regulate the climate and
water cycles — locally, regionally and glob-
ally. Such areas also provide a buffer against
extreme weather and geological events. Sim-
ulations of tsunamis, for instance, indicate
that healthy coral reefs provide coastlines
with at least twice as much protection as
highly degraded ones16.
Wilderness regions are home to some
of the most politically and economically
marginalized indigenous communities on
Earth. These people (who number in the
hundreds of millions) are reliant on intact
marine and terrestrial ecosystems for
resources such as food, water and fibre17.
Many have established biological and cul-
tural connections with their environment
over millennia. Securing the wilderness is
central to reducing their poverty and mar-
ginalization — and to achieving numerous
UN Sustainable Development Goals, from
reducing inequality to improving human
well-being.
GLOBAL TARGETS
We believe that Earths remaining wilder-
ness can be protected only if its importance
is recognized within international policy
frameworks.
Currently, some wilderness areas are
protected under national legislation such
as the 1964 US Wilderness Act, which
protects 37,000km
2
of federal land. But in
most nations, these areas are not formally
defined, mapped or protected, and there
is nothing to hold nations, private indus-
try, civil society or local communities to
account for their long-term conservation.
What is needed is the establishment of
global targets within existing international
frameworks — specifically, those aimed at
conserving biodiversity, avoiding dangerous
climate change and achieving sustainable
development.
There are several ways to do this imme-
diately. The carbon sequestration and stor-
age capacities of wilderness areas could be
formally documented, and the importance
of conserving them written into the policy
recommendations of the UN Framework
Convention on Climate Change (UNFCCC).
Such a move would enable nations to make
the protection of wilderness areas an integral
part of their strategy for reducing emissions.
As an example, under the UNFCCC
process for reducing emissions from defor-
estation and forest degradation (REDD+),
landowners can be compensated if they
refrain from clearing an area of tropical for-
est that they’d planned to develop. However,
there are no incentives for nations, private
industry or communities to protect crucial
carbon sinks, even when no imminent devel-
opment is identified. This means that there
is nothing to stop the slow erosion of these
places from small-scale and often unplanned
industrial activity. Similar policies are needed
to protect other carbon-ri ch ecosystems, such
as seagrass meadows, and temperate and
boreal forests, especially in developed coun-
tries that do not currently receive financial
support under the UNFCCC.
Later this month, Egypt will host the
14th gathering of the Conference of the
Parties to the Convention on Biological
Diversity (CBD). Signatory nations, intra-
governmental organizations such as the
International Union for Conservation of
Nature (IUCN), non-governmental organi-
zations and the scientific community will
meet to work towards a strategic plan for
the protection of biodiversity after 2020.
We urge participants at the meeting to
To map Earth’s remaining terrestrial
wilderness, we used the best
available data on eight indicators of
human pressures at a resolution of
1square kilometre. These were: built
environments, crop lands, pasture
lands, population density, night-time
lights, railways, major roadways and
navigable waterways3,4. (Data were
collected in 2009.) For our map of
intact ocean ecosystems, we used
2013 data on fishing, industrial
shipping and fertilizer run-off, among
16 other indicators2.
We identified wilderness land or
ocean areas as those that were free of
human pressures, with a contiguous
area of more than 10,000 km2 on land.
J.E.M.W.
et al
.
WILD EARTH
Mapping methods
28 | NATURE | VOL 563 | 1 NOVEMBER 2018
COMMENT
include a mandated target for wilderness
conservation. In our view, a bold yet achiev-
able target is to define and conserve 100% of
all remaining intact ecosystems.
A mandated global target will make it
easier for governments, non-governmental
organizations and entities such as the Global
Environment Facility (a multinational fund-
ing programme that tackles environmental
and sustainability problems) to leverage
funding and mobilize action on the ground.
It will also help to enable action under the
various conventions that are attempting to
protect biodiversity. For example, officially
recognizing the contribution that the wil-
derness makes to the ‘outstanding universal
value’ of certain areas could lead to the desig-
nation of new Natural World Heritage Sites.
Under the UN World Heritage Conven-
tion, Natural World Heritage Sites are cur-
rently selected for their outstanding natural
beauty, or because they contain unique bio-
diversity or ecological and geological fea-
tures. The wilderness is associated with all
of these criteria, but its importance has yet
to be specifically acknowledged.
Almost two-thirds of marine wilderness
lies in international waters, beyond the
immediate control of nations. The United
Nations Convention on the Law of the Sea
is currently negotiating a legally binding
agreement to govern high-seas conserva-
tion. Keeping Earth’s remaining marine
wilderness off-limits to exploitation should
be a key component of the new treaty. Strict
limits on government subsidies of harmful
fishing will also be crucial here; without
these, more than half of high-seas industrial
fishing would be unprofitable18.
Our maps exclude Antarctica because it
is off-limits to direct resource exploitation
such as mining, and the indirect effects of
human activities there are harder to meas-
ure. But it is a crucial wilderness area that
is urgently in need
of protection.
Antarctica’s isola-
tion and extreme
conditions have
prevented the lev-
els of degradation
experienced else-
where. But invasive
species, pollution,
increased human
activity and, above all, climate change are
threatening its unique biodiversity and its
ability to regulate the global climate.
The Antarctic Treaty System’s Committee
for Environmenta l Protection has prior itized
research and action targeted at minimizing
human impacts in its latest five-year plan.
Signatory nations must now commit to
implementing measures targeted at reduc-
ing human impacts, such as strict biosecurity
procedures that minimize the risk of visitors
to Antarctica introducing invasive species.
LOCAL ACTION
How can changes in policy at the global level
translate into effective national action?
By our measure, 20 countries contain
94% of the world’s remaining wilderness
(excluding the high seas and Antarctica).
More than 70% is in just five countries —
Russia, Canada, Australia, the United States
and Brazil (see ‘What’s left?’). Thus, the steps
these nations take (or fail to take) to limit the
expansion of roads and shipping lanes, and
to rein in large-scale developments in min-
ing, forestry, agriculture, aquaculture and
industrial fishing, will be critical.
One obvious intervention that these
nations can prioritize is establishing pro-
tectedareas in ways that would slow the
impacts of industrial activity on the larger
landscape or seascape19. Given the scale of
wilderness areas, however, the expansion of
strictly enforced protected areas won’t suff ice.
Several studies show that stopping
industrial development to protect the live-
lihoods of indigenous people can conserve
biodiversity and ecosystem services just as
PAUL NICKLEN/NGC
Emperor penguins
in the Ross Sea.
1 NOVEMBER 2018 | VOL 563 | NATURE | 29
“Mechanisms
that enable the
private sector to
protect, rather
than harm,
wilderness
areas will be
crucial.”
well as strictly protected areas can. As such,
the recognition of local community rights
to land ownership and management could
be a key way to limit the impacts of indus-
trial activity8.
Mechanisms that enable the private sec-
tor to protect, rather than harm, wilderness
areas will be crucial. Specifically, the preser-
vation of intact ecosystems needs to feature
among lenders’ investment and performance
standards, particularly for organizations
such as the World Bank, the International
Finance Corporation and the regional
development banks. Initiatives that enable
companies to declare their supply chains
deforestation-free’ (such as for products
containing palm oil) should be expanded to
help to secure more intact ecosystems.
In the oceans, regional fisheries manage-
ment organizations (RFMOs), formed by
countries to manage shared fishing inter-
ests, have effectively closed large areas of
the high seas. For example, the North East
Atlantic Fisheries Commission (an RFMO
founded in 1980) has shut more than
350,000square kilometres of the Atlantic
to bottom trawling. The power of RFMOs
could be increased to enable the creation of
broader, scaled-up conservation agreements
for the high seas.
Wild places are facing the same extinction
crisis as species. Similarly to species extinc-
tion, the erosion of the wilderness is essen-
tially irreversible. Research has shown that
the first impacts of industry on wilderness
areas are the most damaging11. And once it
has been eroded, an intact ecosystem and its
many values can never be fully restored.
As US President Lyndon B. Johnson
observed when he signed the US Wilder-
ness Act in 1964, “If future generations are
to remember us with gratitude rather than
contempt … we must leave them a glimpse of
the world as it was in the beginning.
Already we have lost so much. We must
grasp this opportunity to secure the wilder-
ness before it disappears forever.
James E. M. Watson is a professor of
conservation science at the University of
Queensland, and director of the Science
and Research Initiative at the Wildlife
Conservation Society, Bronx, New York,
USA. Oscar Venter is an associate professor
at the Natural Resource and Environmental
Studies Institute, University of Northern
British Columbia, Prince George, Canada.
Jasmine Lee is a PhD candidate in the
School of Biological Sciences, University of
Queensland, StLucia, Australia. Kendall R.
Jones is a conservation planning specialist
and John G. Robinson is executive vice-
president of conservation and science at
the Wildlife Conservation Society, Bronx,
New York, USA. Hugh P. Possingham is
chief scientist at The Nature Conservancy,
Arlington, Virginia, USA. James R. Allan
is a postdoctoral research fellow in the
School of Biological Sciences, University of
Queensland, StLucia, Australia.
e-mails: jwatson@wcs.org;
james.allan@uqconnect.edu.au
1. Klein Goldewijk, K., Beusen, A., van Drecht, G. &
de Vos, M. Glob. Ecol. Biogeogr. 20, 73–86 (2011).
2. Jones, K. R. et al. Curr. Biol. 28, 2506–2512 (2018).
3. Allan, J. R., Venter, O. & Watson, J. E. M. Sci. Data
4, 170187 (2017).
4. Watson, J. E. M. et al. Curr. Biol. 26, 2929–2934
(2016).
5. Halpern, B. S. et al. Nature Commun. 6, 7615
(2015).
6. Kareiva, P. & Marvier, M. BioScience 62, 962–969
(2012).
7. Ricketts, T. H. et al. Proc. Natl Acad. Sci. USA 102,
18497–18501 (2005).
8. Watson, J. E. M. et al. Nature Ecol. Evol. 2,
599–610 (2018).
9. D’agata, S. et al. Nature Commun. 7, 12000 (2016).
10. Soulé, M. E. et al. Pacific Conserv. Biol. 10,
266–279 (2004).
11. Betts, M. G. et al. Nature 547, 441–444 (2017).
12. Carilli, J. E., Norris, R. D., Black, B. A., Walsh, S. M.
& McField, M. PLoS ONE 4, e6324 (2009).
13. Mantyka-pringle, C. S., Martin, T. G. &
Rhodes,J.R. Glob. Change Biol. 18, 1239–1252
(2012).
14. Houghton, R. A., Byers, B. & Nassikas, A. A. Nature
Clim. Change 5, 1022–1023 (2015).
15. Howard, J. et al. Front. Ecol. Environ. 15, 42–50
(2017).
16. Kunkel, C. M., Hallberg, R. W. & Oppenheimer, M.
Geophys. Res. Lett. 33, L23612 (2006).
17. Millennium Ecosystem Assessment. Ecosystems
and Human Well-Being: Current State and Trends
(Island Press, 2005).
18. Sala, E. et al. Sci. Adv. 4, eaat2504 (2018).
19. Watson, J. E. M., Dudley, N., Segan, D. B. &
Hockings, M. Nature 515, 67–73 (2014).
Area (millions of square kilometres)
0 10
Other (n = 78)
Egypt
Greenland
United Kingdom
Chad
Norway
Mali
Mauritania
Niger
Denmark
Libya
Algeria
New Zealand
China
Kiribati
France
Brazil
United States
Australia
Canada
Russia
15 205
Terrestrial Marine
Terrestrial Marine
REMAINING WILDERNESS:
Amazon
(Brazil)
Boreal forest (Canada)
Desert (Australia)
Okavango Delta
(Botswana)
THE WILDEST COUNTRIES
Twenty countries contain 94% of the world’s wilderness, excluding Antarctica and the high seas.
WHAT’S LEFT?
The top 5 alone contain more than
70% of the world’s wilderness.
THE HUMAN FOOTPRINT
77% of land (excluding Antarctica) and 87% of the ocean has been modied by
the direct eects of human activities.
Earth’s remaining wilderness areas are becoming increasingly important buers against changing conditions
in the Anthropocene. Yet they aren’t an explicit target in international policy frameworks.
Arctic tundra (Alaska)
SOURCE: REFS 2 & 3
30 | NATURE | VOL 563 | 1 NOVEMBER 2018
COMMENT
... Human activity affects over 77% of the terrestrial land cover, which has had a severe impact on the intactness of natural areas (Beyer et al., 2020;Watson et al., 2018;Williams et al., 2020). A time-series analysis of satellite observations shows a rapid expansion of human land use at the expense of natural land cover (Ellis, 2019;Potapov et al., 2017;Watson et al., 2018). ...
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Thesis
Full-text available
Sub-Saharan Africa is a hotbed of remarkable terrestrial biodiversity, home to a unique diversity of mammals. Unfortunately, this richness is threatened by the growing impact of human activities. While wildlife populations are declining, livestock numbers have been increasing for decades. With significant population growth predicted for the region this century, the pressures on biodiversity are likely to intensify. It is therefore imperative to closely monitor wild and domestic mammal populations. The conventional method of aerial counting using systematic sampling is still widely used to census these populations in open areas. However, the use of on-board photographic sensors on various remote sensing platforms offers the potential to improve and standardize traditional methods. However, processing the large quantities of data generated by these sensors remains a major challenge. In this context, the use of automatic approaches based on deep learning, a branch of artificial intelligence, appears to be a promising solution. The objective of this thesis is therefore to evaluate the effectiveness of the combined use of remote sensing and deep learning for the multi-species census of large African mammals. The research spans several protected areas and considers various mammal species, both wild and domestic. Firstly, I assessed the potential of pre-existing convolutional neural network architectures to automate the detection and identification of wild species in ultra-high resolution (UHR) images (Chapter 2). Three architectures were tested on a dataset comprising six large mammal species. The best model, achieving a mean Average Precision (mAP) of 80%, was applied to an independent dataset from Garamba National Park, Democratic Republic of Congo. It showed superior detection performance to previous studies in similar habitats, opening up promising prospects. However, detection limits were observed for the smallest species (warthog, Phacochoerus africanus), and a drop in precision was observed in herd situations for African elephant (Loxodonta africana) and buffalo (Syncerus caffer), due to a high number of false positives. Secondly, I developed a novel deep learning architecture named HerdNet in response to the limitations of pre-existing models (Chapter 3). HerdNet is a point-based object detector inspired by crowd-counting techniques. It has been tested on oblique images of domestic herds of camel (Camelus dromedarius), donkey (Equus asinus), sheep (Ovis aries) and goat (Capra hircus) from the Ennedi Natural and Cultural Reserve in Chad. HerdNet demonstrated better detection and counting accuracy than previous methods, on both oblique (+26% of F1 score) and nadir UHR images (+32%). In addition, it solves the problem of false positives in dense herd situations, with proximity-invariant precision. Although species identification could be improved, the practical benefits and potential use of HerdNet were discussed, promising a significant reduction in the human interpretation time associated with aerial surveys. Thirdly, I evaluated the contribution of oblique UHR imagery and deep learning on systematic aerial sample surveys, in a semi-automatic detection context (Chapter 4). I first quantified the reduction in human workload associated with the manual interpretation of oblique images acquired by an on-board camera system on light aircraft. HerdNet was used to detect, count and identify 12 animal species in the Queen Elizabeth Protected Area, Uganda, resulting in a 74% reduction in the number of images to be interpreted by humans. Next, I examined whether a semi-automated approach, incorporating HerdNet, combined with oblique image acquisition, improves the accuracy and precision of population estimates compared with the traditional method. This comparison was carried out for seven key species (e.g. elephant; waterbuck, Kobus ellipsiprymnus ssp. defassa; western hartebeest, Alcelaphus buselaphus ssp. major) in Comoé National Park, Côte d'Ivoire, covering 11,500 km². The semi-automatic approach showed significantly higher population estimates for smaller species, i.e. +241% for kob (Kobus kob spp. kob) and +163% for warthog (Phacochoerus africanus ssp. africanus), with tighter confidence intervals. However, the obstruction of animals by vegetation had a substantial impact on their detection in the images. Finally, human effort in the semi-automated approach was significantly reduced when compared to fully manual interpretation (estimated at -98%), resolving the major challenge of photographic methods. In conclusion, this thesis highlights the importance of using remote sensing and deep learning to standardize surveys of large African mammals and efficiently process the growing volume of images generated. Although the approach presented still requires further validation, the results obtained suggest a real potential to revolutionize traditional aerial survey methods. Consequently, the advancement of current aerial survey standards should be considered, as well as the use of other acquisition platforms (e.g. microlight aircrafts), less costly and less challenging to deploy than light aircraft. As for satellites, while recent advancements in image-based ecological monitoring have propelled their potential ahead of other methods, current constraints limit its viability as an immediate alternative. Nevertheless, the use of their images might serve as a valuable complement to organize and deploy other data acquisition platforms, rather than as a standalone survey solution. It is therefore crucial to foster interdisciplinary collaboration to promote these new technological approaches, which will help improve biodiversity monitoring and its long-term preservation.
... This 'wilderness conservation' approach has the potential to deliver long-term benefits at the cost of frontier woodland loss (Watson et al., 2018) and may induce leakages and rebound effects of cropland expansion in and around the area of conservation interest . Some evidence shows that remote protected areas with lower initial human pressure may experience more human pressure after establishment, and deforestation pressure can increase within protected areas once the surrounding forest is lost (Buřivalová et al., 2021;Geldmann et al., 2019). ...
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