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Conservation Biology in Sub-Saharan Africa

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Nguyễn Gia Hào

Academic year: 2023

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Among the most popular are radar products (Figure 10.4), which have become standard methods for obtaining elevation and terrain data (NASA as well as carbon stock estimates (Carreiras et al., 2012). Most importantly, remote sensing applications cannot be considered reliable without verification using field data (see Burton 2017,).

Table 10.1 Three ways how humans have changed the natural world.
Table 10.1 Three ways how humans have changed the natural world.

Maintaining Complex and Adaptive Ecosystems

  • Maintaining critical ecosystem processes
  • Minimising external threats
  • Adaptive management
  • Being minimally intrusive

Biocontrol also offers the opportunity to control invasive species that are difficult to manage with chemical pesticides and mechanical control (at least without significant additional damage to the environment), such as submerged aquatic weeds (Coetzee et al., 2011). The tick berry, for example, continues to thrive despite the release of over 40 biocontrol agents (Zalucki et al., 2007).

Figure 10.4 A radar composite of equatorial Africa obtained in 1996 by Japan’s Earth Resources Satellite
Figure 10.4 A radar composite of equatorial Africa obtained in 1996 by Japan’s Earth Resources Satellite

Restoring Damaged Ecosystems

Ecological restoration approaches

Land managers restore some ecosystem functions and some of the species that were dominant or characteristic of the ecosystem. Land managers restore an area to determine ecosystem structure, species mix, and ecosystem functioning.

Figure 10.10 Several approaches can be followed when restoring an ecosystem, ranging from taking no  action and letting the ecosystem regenerate naturally to completely restoring a degraded site
Figure 10.10 Several approaches can be followed when restoring an ecosystem, ranging from taking no action and letting the ecosystem regenerate naturally to completely restoring a degraded site

Major restoration targets

Fortunately, many African plant species are also good candidates for sustainable restoration initiatives, including camphor bush (Tarchonanthus camphoratus), sickle-leaved false thistle (Albizia harveyi), silverleaf (Terminalia sericea), and weeping eyelash (Peltophorum ; Friencandy 2005; 2005). They are also among the most important carbon sinks in the world, storing four times more carbon per hectare than other tropical forest types (Donato et al., 2011).

Figure 10.D (Top)  June  2016:  project  participants  planting  trees  on  the  University  of  Nairobi,  Chiromo campus, following the Miyawaki method; (Bottom)
Figure 10.D (Top) June 2016: project participants planting trees on the University of Nairobi, Chiromo campus, following the Miyawaki method; (Bottom)

The future of ecological restoration

They provide food to local communities, support ecotourism industries and protect coasts by reducing wave energy by as much as 97% (Ferrario et al., 2014). Still, restoring coral reefs is worth the effort; a meta-analysis found that it is almost 20 times cheaper to restore coral reefs than to construct artificial coastal protection systems (Ferrario et al., 2014).

Combatting Climate Change Through Ecosystem Conservation

100 years to develop (Bonnell et al., 2011) – so it may take decades for even effective restorations to deliver full benefits. For example, there are concerns that REDD+ programs could develop into a form of perverse subsidies, for example when native vegetation is cut down to create plantations (Figure 10.12) with trees at high risk of becoming invasive (Lindenmayer et al., 2012).

Summary

Similarly, there are concerns about the strong emphasis on forests, possibly at the expense of other important ecosystems and ecosystem services (Bond, 2016). However, there are concerns that some REDD+ funds have become a form of perverse subsidies, for example when native vegetation is cleared to establish plantations of invasive trees.

Topics for Discussion

Suggested Readings

Bibliography

Studying Species and Populations

  • Obtaining natural history data

To save a species from extinction, it is essential to have a firm grip on the species. To save a species from extinction, it is essential to have a firm grip on the species' distinctive characters, in others.

Figure 11.A  The oribi is a grassland specialist that requires both short and tall grasslands and tends  to forage at least 15 m from wooded patches
Figure 11.A The oribi is a grassland specialist that requires both short and tall grasslands and tends to forage at least 15 m from wooded patches

Saving Species Through Translocations

  • Important considerations for translocations

Great progress has also been made in calculating predator carrying capacity by monitoring prey densities (Hayward et al., 2007a). Another study found that reintroduced cheetahs were all killed within a year of release (Houser et al., 2011).

Figure 11.4  A team of wildlife  rehabilitators release a group of  Cape vultures (Gyps coprotheres,  EN) near a vulture restaurant in  South Africa
Figure 11.4 A team of wildlife rehabilitators release a group of Cape vultures (Gyps coprotheres, EN) near a vulture restaurant in South Africa

Managing and Facilitating Movement Dynamics

  • Connectivity in terrestrial ecosystems
  • Connectivity in freshwater ecosystems
  • Connectivity in marine ecosystems
  • Mimicking connectivity
  • Management considerations in connectivity conservation

In contrast, protection of riparian zones has been found to increase palm oil yields (Horton et al., 2018). See also Dupuis-Desormeaux et al., [2018] for the use of fence gaps and exclusion fences to mitigate some negative fence impacts.).

Figure 11.9  Protecting riparian  zones  such  as  this  one  along  the Turkwel River in northern  Kenya is an effective strategy  for maintaining connectivity  and securing a range of  ecosystem services
Figure 11.9 Protecting riparian zones such as this one along the Turkwel River in northern Kenya is an effective strategy for maintaining connectivity and securing a range of ecosystem services

Managing Species Sensitive to Climate Change

While slowing habitat loss could slow the overall impacts of climate change (Section 10.4), preventing the extinction of many climate-sensitive species will require a range of proactive conservation management strategies that allow species to adapt at their own pace as and when necessary. Supported colonization, also called supported migration, involves the proactive relocation of climate-sensitive species.

Ex Situ Conservation Strategies

  • Types of ex situ facilities
  • Challenges facing ex situ facilities

Ex situ and in situ conservation are complementary strategies (Figure 11.13; see also Conde et al., 2011). Protecting a well-represented sample of the world's biodiversity plays only a minor role in ex situ conservation efforts.

Figure 11.13  There are several ways in which in situ (on site) and ex situ (off-site) conservation can comple- comple-ment each other
Figure 11.13 There are several ways in which in situ (on site) and ex situ (off-site) conservation can comple- comple-ment each other

Thoughts on Neglected Taxa

However, conservation biologists working in ex situ facilities are constantly trying to find ways to overcome these challenges. Others use cryopreservation and genome resource banks for long-term storage of embryos, eggs, sperm, or purified DNA, at least until those tissues can be used to increase the genetic diversity of a species, or perhaps even to revive an extinct species (see extinction, Section 8.8).

Figure 11.D  (Top) The world’s first African buffalo calf conceived by in vitro fertilisation
Figure 11.D (Top) The world’s first African buffalo calf conceived by in vitro fertilisation

Summary

One explanation for this difference is that plants are often seen as the background of the environment rather than the critical basis (as primary producers) of any food web on Earth. Some groups of experts are also organized into Specialist Groups (https://www.iucn.org/ssc-groups) of the IUCN.

Topics for Discussion

Suggested Readings

Patterns of elephant impact on woody plants in the Hluhluwe-iMfolozi Park, Kwazulu-Natal, South Africa. Options for moose: A multiscale assessment of antipredator responses of a vulnerable prey species to their main predator in the Eastern Cape, South Africa.

Identifying Legislative Priorities

As with other crimes, environmental crimes are generally defined by legislative action, when governments pass environmental laws and regulations that restrict certain types of activities. The effectiveness of these laws and regulations in protecting the environment rests on three main factors: (1) identification of conservation priorities, (2) establishment of regulations that address those needs, and (3) enforcement of environmental laws and regulations.

Figure 12.1  Key global ivory smuggling routes from 2009–2011, based on seizure data. More recent work  has  shown  that  poached  elephants  continue  to  originate  from  Tanzania,  Mozambique,  and  Cameroon,  while several seizures were now also from G
Figure 12.1 Key global ivory smuggling routes from 2009–2011, based on seizure data. More recent work has shown that poached elephants continue to originate from Tanzania, Mozambique, and Cameroon, while several seizures were now also from G

Environmental Laws and Policies

  • International agreements
  • National and local laws

One of the most important international environmental treaties is the Convention on Biological Diversity (CBD, https://www.cbd.int). International treaties are particularly important for the marine environment, as about two-thirds of the world's oceans (50% of the planet) fall outside any.

Table 12.1  The UN, with governments across the world, have agreed to work on five  strategic goals and 20 specific targets (collectively known as Aichi Biodiversity Targets) to
Table 12.1 The UN, with governments across the world, have agreed to work on five strategic goals and 20 specific targets (collectively known as Aichi Biodiversity Targets) to

Environmental Law Enforcement

  • New technologies in environmental law enforcement

An example is South Africa, where over 500 current and potential invasive species are classified into three categories (http://www.invasives.org.za): Category 1 (immediately destroyed, cannot be owned), Category 2 (kept only by permit, no trade) and Category 3 (no trade, no breeding, but no need to remove) (Z). Conservationists have also become more aware of the strategies they use to plan and conduct law enforcement monitoring.

Figure 12.5  Rangers at Garamba  National Park, DRC, found 73  kg of giant ground pangolin  (Smutsia gigantea,  VU)  scales  (from about 20 animals) and  two elephant tusks in this  hand-cuffed  poacher’s  possession
Figure 12.5 Rangers at Garamba National Park, DRC, found 73 kg of giant ground pangolin (Smutsia gigantea, VU) scales (from about 20 animals) and two elephant tusks in this hand-cuffed poacher’s possession

CONTROL ROOM

Analyse information and identify a potential incident

The Limits of Environmental Laws and Regulations

  • Lack of capacity
  • Conflicting government priorities
  • Informal economies, traditional activities, and the law
  • Trade embargoes and sanctions

Today, the $91–258 billion environmental crime industry is the world's fourth largest illegal enterprise, after drug smuggling, counterfeiting, and human trafficking ( Nellemann et al., 2016 ). It is therefore important to carefully explain the reasoning behind those changes (e.g. “bushmeat hunting drives away tourist dollars”, Rogan et al., 2017).

Figure 12.6  Fishermen from Tanji  fishing village in The Gambia  fixing their nets after a day out  at sea
Figure 12.6 Fishermen from Tanji fishing village in The Gambia fixing their nets after a day out at sea

Conclusion

The two main causes of the alarmingly rapid loss of wildlife in Africa today are: (1) unsustainable use of land and natural resources, mostly related to decision-making that does not prioritize conservation considerations; and (2) overharvesting of wild animals and plants through poaching and illegal logging. Poaching and illegal logging may be driven locally for subsistence use, due to poverty; due to a lack of other protein, energy and income sources;.

Figure 12.D  In 2004,  Angolan authorities confiscated Massamba, an orphaned chimpanzee (Pan  troglodytes, EN),  from poachers, as part of a crackdown on the illegal wildlife trade
Figure 12.D In 2004, Angolan authorities confiscated Massamba, an orphaned chimpanzee (Pan troglodytes, EN), from poachers, as part of a crackdown on the illegal wildlife trade

Summary

Topics for Discussion

Suggested Readings

A biome-scale assessment of the impact of invasive alien plants on ecosystem services in South Africa. Exposing the illegal trade of cycad species (Cycadophyta: Encephalartos) in two traditional medicine markets in South Africa using DNA barcoding.

Sea anemones and cold-water corals are among the species that enjoy protection in the 1000 km 2  Table Mountain  National Park Marine Protected Area (MPA), South Africa
Sea anemones and cold-water corals are among the species that enjoy protection in the 1000 km 2 Table Mountain National Park Marine Protected Area (MPA), South Africa

Establishing Protected Areas

  • Government protected areas
  • Community conserved areas
  • Privately protected areas
  • Co-managed protected areas
  • Field stations and marine laboratories

Because the ecotourism potential of these privately protected areas depends on how well the property is managed (Clements et al., 2016), private landowners often invest significant efforts to maintain and even expand the wildlife populations on their land. In some areas, private conservation areas can even employ more people, pay better wages, and contribute more to the local economy than government protected areas (Sims-Castley et al., 2005).

Figure 13.1  Land clearing and agricultural development pushes right up to the eastern edge of Bwindi  Impenetrable  National  Park,  Uganda
Figure 13.1 Land clearing and agricultural development pushes right up to the eastern edge of Bwindi Impenetrable National Park, Uganda

Classification of Protected Areas

Today, there are biological field stations in at least 24 sub-Saharan African countries (Tydecks et al., 2016). Among them are Namibia's Gobabeb Research and Training Center which focuses on desert conservation, Kenya's Mpala Research Center (Box 13.1) which investigates the potential for wildlife and livestock to coexist, Nigeria's A.P.

Figure 13.A  Participants in the Kid’s Twiga Tally trying to differentiate individual giraffes using  photos to understand how the IBEIS software works
Figure 13.A Participants in the Kid’s Twiga Tally trying to differentiate individual giraffes using photos to understand how the IBEIS software works

Prioritisation: What Should be Protected?

  • Species approach
  • Ecosystem approach
  • Wilderness approach
  • Hotspot approach
  • Gap analysis approach
  • Optimisation approach

Existing protected areas (all marked) were enclosed, but proposed protected areas such as Itombwe and Kabobo and community reserves (purple border) were not. One of the most popular packages is Marxan (http://marxan.org), a freely available program that identifies the optimal location for protected areas based on flexible, user-defined criteria (Watts et al., 2009).

Table 13.1  Description of Categories I–VI of the IUCN’s classification of protected areas.
Table 13.1 Description of Categories I–VI of the IUCN’s classification of protected areas.

How Much Land Should We Protect?

  • A neglected system: marine protected areas

Furthermore, the amount of protected land does not necessarily mean adequate protection for all ecosystems (Watson et al., 2016). There is also an urgent need to increase law enforcement in the marine environment (Brashares et al., 2004).

Figure 13.4  The location of Sub-Saharan Africa’s terrestrial and marine protected areas (MPAs), which falls  under the IUCN’s categories I–VI classification for protected areas
Figure 13.4 The location of Sub-Saharan Africa’s terrestrial and marine protected areas (MPAs), which falls under the IUCN’s categories I–VI classification for protected areas

Designing Protected Areas

  • What size should a protected area be?
  • Zoning as a solution to conflicting demands
  • Connectivity among protected areas
  • What about small isolated reserves?

But we now know that wildlife populations are often distributed among protected areas through the surrounding habitat matrix (Pryke et al., 2015). Many of the strategies used to maintain and restore ecosystem connectivity (Section 11.3) can be applied to the management of protected areas.

Figure 13.D  Vamizi Island has some of the world’s richest and most pristine coral reefs, as well  as the last population of the grey reef shark (Carcharhinus amblyrhynchos, NT) in Mozambique
Figure 13.D Vamizi Island has some of the world’s richest and most pristine coral reefs, as well as the last population of the grey reef shark (Carcharhinus amblyrhynchos, NT) in Mozambique

Managing Protected Areas

  • The importance of monitoring
  • The importance of working with local people
  • The importance of accommodating visitors
  • The IUCN Green List of Protected Areas

This is the case in South Africa, where the regional conservation authority Ezemvelo KZN Wildlife allows local people to sustainably harvest plant resources, such as thatched grasses and medicinal plants, from protected areas they manage (Beale et al., 2013b; see also Section 13.5.2). Developing plans that accommodate outside visitors is also an important aspect of protected area management.

Figure 13.7 Satellite imagery provides a cost-effective method for monitoring ecosystem conditions, both  inside  and  outside  protected  areas
Figure 13.7 Satellite imagery provides a cost-effective method for monitoring ecosystem conditions, both inside and outside protected areas

Challenges for Protected Areas

  • Funding limitations
  • Planning for climate change
  • Facing degazettement

The cost of these resources can add up quickly; for example, researchers estimate that more than $1 billion is needed each year to manage Africa's protected areas, including lion populations (Lindsey et al., 2018). Yet, Africa's protected areas are often understaffed, lacking basic equipment and facing funding gaps (Tranquilli et al., 2014; Watson et al., 2014).

Figure 13.10  The list of generic standards, to be adapted for local contexts, against which protected areas  will be evaluated before achieving IUCN Green List of Protected Areas status
Figure 13.10 The list of generic standards, to be adapted for local contexts, against which protected areas will be evaluated before achieving IUCN Green List of Protected Areas status

Summary

While there are legitimate reasons for some PADDDs (Fuller et al., 2010), few have been conducted with conservation goals in mind. As a general guideline, protected areas should be large and not fragmented where possible.

Topics for Discussion

Managing interactions with local residents and visitors is essential to the success of protected areas and should be part of a management plan.

Suggested Readings

Assessing the relationship between pathways of alien plant invaders and their impacts in protected areas. Well-managed protected areas are essential tools for ensuring intact ecosystems and the biodiversity they sustain.

Human-Dominated Landscapes

Damage to ecosystems such as rivers and streams in unprotected areas has repeatedly been shown to reduce biodiversity even within protected areas (Colvin et al., 2011; Woodborne et al., 2012). Furthermore, many species only occur in unprotected areas (Beresford et al. 2011), and some species even do better outside protected areas (Murgatroyd et al., 2016).

Turning the Page

As an alternative to retaliatory killing, the Kenyan government financially compensates herders for predation losses; however, the government has not always been consistent in this compensation (Goldman et al., 2010). Communal lands in East Africa dedicated to pastoralism are a good example illustrating the compatibility between traditional peoples and conservation efforts (McGahey et al., 2007).

Figure 14.2  Green infrastructure enables people living in urban centres to reduce their pressure on natural  ecosystems and live more comfortable lives
Figure 14.2 Green infrastructure enables people living in urban centres to reduce their pressure on natural ecosystems and live more comfortable lives

Insights from the City of Cape Town

The impact of agriculture

To make matters worse, much of sub-Saharan Africa's arable land has already been degraded to such an extent that it can no longer support viable food production (Drechsel et al., 2001). Such land conflicts are only going to get worse with climate change (Zabel et al., 2014).

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Figure 10.4 A radar composite of equatorial Africa obtained in 1996 by Japan’s Earth Resources Satellite
Figure 10.5 A food pyramid of a model savannah ecosystem, showing the various trophic levels and energy  pathways
Figure 10.7 Data on the control of invasive species in South Africa have shown that the larger the infesta- infesta-tion (a funcinfesta-tion of time passed since establishment), the more resources are required for eradicainfesta-tion
Figure 10.8 Members of South Africa’s Working for Water programme mechanically removing invasive  Australian wattles (Acacia spp.)
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