Shrinking Biodiversity. Current Status and Perspectives in Madagascar and Tanzania

Table of Contents

Table of Contents

List of Abbreviations

Abstract

Tanzania
Value of Biodiversity to Tanzania
Biodiversity Status
Terrestrial Ecosystems
Species and Plant Diversity
Coastal and Marine Ecosystem
Inland Water Ecosystem
Threats to Biodiversity
Trends in Biodiversity
Nature Conservation Programs
Section Conclusion

Madagascar
Value of Biodiversity to Madagascar
Economic Values
Socio-cultural Values
Scientific Values
Biodiversity Status
Ecosystem Status
Species Status
Trends in Biodiversity
Trends at Ecosystems Level
Trends at Species Level
Threats to Biodiversity
Nature Conservation Programs
Section Conclusion

References
Tanzania
Madagascar

List of Abbreviations

CBD Convention on Biological Diversity

CDC Country Development Cooperation

COVID-19 Coronavirus disease

DLC Duke Lemur Center

DNA deoxyribonucleic acid

FAO The Food and Agriculture Organization

GDP Gross Domestic Product

IUCN International Union for Conservation of Nature

MAST Manifattura di Arti, Sperimentazione e Tecnologia

MEA Millennium Ecosystem Assessment

MEF Ministry of Environment and Forests

MRPA Managed Resources Protected Areas

NBSAP National Biodiversity Strategies and Action Plans

NGOs Non-Governmental Organizations

PA Protected Area

PROTECT Promoting Tanzania's Environment, Conservation, and Tourism

RTI Research Triangle Institute

SCBD The Secretariat of the Convention on Biological Diversity

UNDP The United Nations Development Program

UNEP-WCMC The UN Environment Programme World Conservation Monitoring Centre

UNESCO The United Nations Educational, Scientific and Cultural Organization

USAID The United States Agency for International Development

USD The United States Dollars

WCS Wildlife Conservation Society

WD-OECM World Database on Other Effective Area-based Conservation Measures

WDPA The World Database on Protected Areas

WWF World Wildlife Fund

Abstract

In the post-industrial period and currently, the biodiversity loss is accelerating globally. Tanzania and Madagascar possess a very high degree of biodiversity of ecosystems, plants and wildlife sustaining critically the livelihoods and wellbeing of millions of people. Both countries face extinction of endemic, as well as other species, degradation of habitats as a result of mainly the poverty, climate change, invasive species, agricultural expansion and lack of effective natural resources management and conservation education of population. In the framework of Convention on Biological Diversity, these East African countries have set goals and targets to tackle the imminent and long-term threats to biodiversity. However, alarming trends continue and threaten the ecosystems and vulnerable species of the countries with extinction such as deforestation and species extinction among others. More investment needs to be spent on existing research and effective management practices if the loss of biodiversity is to be reversed.

"We have reached an unprecedented moment whereby humans change the Earth and its processes more than all other natural forces combined".

Edward Burtynsky - The Anthropocene Project, MAST Foundation

In almost all Earth's ecosystems, biodiversity loss is on the rise. In order to grasp the seriousness of this global trend it is necessary to have a common understanding of the concept and know why it is important at all. The Convention on Biological Diversity (CBD) defines biological diversity as being “the variability among living organisms from all sources including, inter alia, terrestrial, marine and other aquatic ecosystems and the ecological complexes of which they are part; this includes diversity within species, between species and of ecosystems” (Convention on Biological Diversity, 1992). The definition delineates three aspects of biodiversity, namely, genetic diversity, species diversity and ecosystem diversity. Genetic diversity is based on the idea that even the members of same species are different at genetic or DNA level and this drives the evolution process by natural selection (Hughes, Brian D.Inouye, Marc T. J. Johnson, Nora Underwood, & Mark Vellend, 2008). Species diversity is a simple measure of count of species within a genus (Macarthur, 1965), while ecosystem diversity refers to quantity, types and patterns of terrestrial and marine/wetland ecosystems and the living processes in them (Burton V. Barnes & Marc Lapin, 1995).

The importance of biodiversity is not complex to understand. Considering the values of ecosystems and species diversities such as environmental services that sustain different crucial life cycle processes, their economic value and socio-cultural role for especially the developing countries, it is apparent that even one species matters when it comes to wellbeing of nature, including the humans. However, unfortunately, in the post-industrial period and currently, the biodiversity loss is accelerating. A feature article published in 2009 in Nature journal illustrates the nine planetary boundaries and shows that biodiversity boundary has been critically trespassed thanks to anthropogenic impacts threatening the functioning of the whole planet (Rockström, et al., 2009). Although at a preliminary level, this article proposes the extinction rate as an indicator of when Earth would lose its resilience due to biodiversity loss and suggests a tipping point of ten species per million species per year. It also states that this century would witness climate change as the main drivers of biodiversity loss coupled with other human-induced changes leading to almost 30% of mammals, amphibians and bird species being in danger of extinction.

The current paper discusses the biodiversity status and perspectives of two of biologically and culturally richest countries in the world – Tanzania and Madagascar. These East African countries possess a very high degree of biodiversity of ecosystems, plants and wildlife sustaining critically the livelihoods and wellbeing of millions of people. At same time, Tanzania and Madagascar have one of lowest human development indices in the world emphasizing the value of biodiversity to these countries and explaining the current rate of overexploitation and other human activities in relation to biodiversity.

Tanzania

In this section, biodiversity of Tanzania is discussed in more detail. The landscape and significance of biodiversity in Tanzania will be covered first, followed by the present state of biodiversity and threats. Conservation programs and a section conclusion will be addressed at the end of this section.

Value of Biodiversity to Tanzania

Tanzania is East Africa's largest country, with the islands of Zanzibar, Pemba, and Mafia. Besides the modest coastal belt of the mainland and the surrounding islands, the majority of mainland Tanzania is over 200 meters in height. The East African Rift System cuts through mainland Tanzania in two north-south sections, creating a span of narrow, deep depressions mainly filled with lakes (National Geographic, n.d.). Between the two branches is the central plateau, which covers more than a third of the nation. Africa's highest point, Mount Kilimanjaro, is surrounded by three of the continent's greatest lakes: Lake Tanganyika (world's second deepest lake), Lake Nyasa and the world´s second-largest freshwater lake, Lake Victoria (National Geographic, n.d.). Tanzania's inland water covers roughly 59,000 square kilometres, due to its many lakes. The diversity of soils in mainland Tanzania outnumbers that of any other African country. The most fertile soils are reddish brown volcanic soils found in the highlands. Many river basins offer good soils as well, although they are prone to floods and require drainage management. The inner plateaus' red and yellow tropical loams, however, have a moderate-to-poor fertility (Mascarenhas et al., n.d.).

Tanzania's mainland is divided into four distinct climatic and geographical zones:” the hot and humid coastal lowlands of the Indian Ocean shoreline, the hot and arid zone of the broad central plateau, the high inland mountain and lake region of the northern border, where Mount Kilimanjaro is situated, and the highlands of the northeast and southwest, the climates of which range from tropical to temperate” (Mascarenhas et al., refers to climate section., n.d.).

Approximately 90 percent of Tanzanians live in rural regions and rely on what they can cultivate on their land to survive. Tanzania has a significant number of natural resources that boost the economy and improve human well-being. Hence, biodiversity is a big driver for Tanzania's economy. Given the above, Tanzania´s wealth of biodiversity is extremely important to the country. Fishing, livestock, agriculture, and forestry combined account for more than 65 percent of GDP, more than 60 percent of total export earnings and over 80 percent of total employment (5th National Report, 2014). The country is benefiting considerably from biodiversity as it is crucial for attracting tourists, food source, pharmaceuticals, for decomposing organic waste and soil conditions, and building energy and materials. Likewise, the industry is relying heavily on biodiversity especially agro, forest, pharmaceutical- and food industries. Tanzania is one of the world’s greatest reservoirs of biodiversity due to its huge national parks, wetlands, marine, and freshwater systems, significant reservoirs of plant and animal species, the Eastern Arc mountains, and coastal forests. Tanzania has 18 endemic lizard species, ten bird species, 31 endemic amphibian species, nine snake species, roughly 80 percent of the renowned African violet flowers, and 40 percent of the world´s wild coffee types (5th National Report, 2014). Moreover, World Heritage Sites add a great value to the biodiversity: Serengeti National Park, Selous Game Reserve, Kilimanjaro National Park, Ngorongoro Conservation Area as well as three Biosphere Reserves, i.e. Lake Manyara, Ngorongoro – Serengeti and East Usambara. These reserves are home to a diverse range of mammals, reptiles, birds, and amphibians, all of which contribute significantly to security of food, government revenue, and community income (5th National Report, 2014).

Biodiversity Status

The United Republic of Tanzania is very rich in biodiversity and one of the mega-biodiversity rich countries worldwide. Tanzania's mega-biodiversity is found in both protected and non-protected places and encompasses ecosystems, species, and genetic resources. “Tanzania's natural ecosystems are split into three groups: terrestrial ecosystems, coastal and marine ecosystems, and inland water ecosystems (lakes, rivers, dams, and wetlands)” (NBSAP, 2015, p. 11).

Tanzania hosts six of the 25 globally known biodiversity hotspots: The Great Lakes for Cichlid fishes; the Marine Coral Reef ecosystems; The Eastern Arc Old Block-Mountain Forests; the Coastal Forests; the Ecosystems of the Alkaline Rift-Valley Lakes; and the grassland savannas for large mammals (e.g., Serengeti Park) (SCBD, n.d.). The Eastern Arc Mountains in Tanzania and Kenya comprise the majority of Tanzania's wet montane tropical forest and are East Africa's biologically richest area for its size. They also have the highest percentage of endemic species of any East African region and are one of the world’s 17 most endangered tropical forest ecosystems or global hotspots (Newmark, 2002).

Terrestrial Ecosystems

Forests, mountains, drylands, savannah, and agricultural lands are types of terrestrial ecosystems. Tanzania's forest cover is approximately 48 million hectares (about 55 percent of the total land area), with woods accounting for around 51 percent of the total land area, or 93 percent of the forest area. The rest of seven percent are lowland forests, mangrove forests, plantations, and humid montane forests. Additionally, Tanzania has roughly 44 million hectares of agricultural land (NBSAP, 2015).

The natural forests of Tanzania are divided into three categories: montane forests, mangroves and miombo woods. The majority of the montane forests have a high-water catchment value, making them a key river source. Yet, African Sandalwood field stocks have plummeted, and human pressure on this species is so intense that it is on the verge of extinction unless immediate silvicultural treatments¹ are implemented (6th National Report, 2019). Mangroves are high-productivity environments that produce significant amounts of organic matter that provides food for a variety of organisms. They further contribute to the stabilization of the shoreline by preventing erosion, filtering water, and settling sediments that might otherwise harm seagrass habitats and coral reefs. However, the density of Mangroves has decreased significantly over the years (Torell et al, 2007).

Species and Plant Diversity

The country has a large number of species, with at least 14,500 known and documented species, and is one of the 15 countries in the world with the most endemic and vulnerable species. It accounts for nearly four percent of all threatened species worldwide. Tanzania is also home to more than a third of Africa's total plant species and ranks 12th in the world in terms of bird species (SCBD, n.d.). Tanzania has between 400 and 3,000 endemic species, with mammals and cycads having the highest proportion of threatened species, and amphibians and plants having the highest number of threatened endemic species. Endemic plants are African Blackwood (Mpingo), African Teak (mninga), Erythrina schliebenii, Karomia gigas (one of the world's rarest trees) and Uvariodendron gorgonis (evergreen tree) and marine animals as sea turtles, as well as coelacanth and dugongs (NBSAP, 2015). Over the previous decade, the number of vulnerable species in the country has nearly tripled, which can be attributed to habitat loss, overexploitation, fragmentation, and degradation, along with climate change effects (SCBD, n.d.). The black rhinoceros, shoebill stork, wild dog, Kihansi Spray toad, chimpanzee, red colobus monkey, African elephant, cheetah, and wattled crane all have significant populations in Tanzania that are endangered and threatened. The savannah grasslands, defined by the dry miombo woods, make up a large portion of the wildlife region (SCBD, n.d.). Tanzania has a high level of species endemism that can be linked to the country's complex topography and biological isolation in some places, generating unique microclimates and ecological circumstances that support the several endemic species (NBSAP, 2015).

Coastal and Marine Ecosystem

The coastal zone of Tanzania is rich in wildlife and natural resources. Coral reefs, mangrove forests, seagrass beds, and maritime fisheries are all significant ecosystems. Tanzania's coastal and marine ecosystems cover roughly 241,500 km2, which is about 20 percent of the total land area of the country. Coral reefs are high-diversity, high-productivity tropical shallow-water habitats. They run the length of Tanzania's continental shelf, which is 600 kilometres long. Tanzania’s coral reefs are home to approximately 500 species of fish and other invertebrates, making them a valuable fisheries resource that supports 90 percent of artisanal marine fisheries over 3,580 km2. However, human, and natural threats have decreased coral reefs tremendously (Torell et al, 2007).

Inland Water Ecosystem

Lakes, rivers, springs, natural ponds, subterranean sources, man-made reservoirs, and wetlands are among Tanzania's abundant freshwater resources. Lakes cover roughly six percent of the land area and include the transboundary major lakes that are Lake Tanganyika, Lake Victoria and Lake Nyasa. Kilombero, Rufiji, Wami, Mara, Ruaha, Ruvuma, Malagarasi, Kagera, and Pangani, as well as their tributaries and accompanying small streams, form a varied network of permanent and seasonal rivers. Many rivers are not protected, with the exception of a few rivers located within protected areas, and hence face decreasing ecological integrity as well as disturbance of ecosystem goods and services they provide (NBSAP, 2015). The large lake system, inland drainage systems, important river networks, and deltaic mangroves account for around ten percent of the country's territory that equals around 88,300 km2 of total land area. Wetlands are one of the most productive ecosystems and are consequently essential for energy generation, water retention, flood control, groundwater recharge, and river and lake eutrophication prevention, as well as, maintaining specialized biota and traditional uses. Many wetlands were automatically protected a few decades ago because of their remoteness, size, and negligible utility for agriculture or other economic activity. Nonetheless, as a consequence of various socioeconomic developments, the country's wetlands have recently undergone fast conversion, leading to their degradation. Tanzania's wetlands are home to about 650 different species of molluscs, crabs, and fish (6th National Report, 2019).

Threats to Biodiversity

The Millennium Ecosystem Assessment report demonstrates that biodiversity loss is related to environmental changes that have occurred at a faster rate in the last 50 years than at any other time in human history (MEA, 2005). Tanzania's biodiversity is facing significant reductions in ecosystem quality, species abundance, and diversity, despite its biological richness and conservation efforts. There are many pressing issues confronting biodiversity in Tanzania. The most urgent are: resource overexploitation, overgrazing, over-dependency of fuel wood for domestic use and bush fires as well as other influences on biodiversity and conservation as poverty, a lack of alternative energy sources, influx of immigrants, spread of alien species (water hyacinth, Nile perch), and a lack of community awareness about biodiversity protection (6th National Report, 2019). Invasive alien species are one of the world's most serious dangers to indigenous biodiversity, and their invasion and persistence will eventually result in a drastic reduction in biodiversity. They also have the potential to outgrow indigenous species. Over 60 species have been reported as invasive species in Tanzania (Kideghesho, Mwamende & Selemani, 2013). Agricultural methods, changes in atmospheric composition and climate change, and biological pest management are the biggest factors through which invasive alien species are introduced (NBSAP, 2015).

In addition, bush fires are on the rise, burning an average of eleven million hectares per year, primarily as a result of human activities such as farm preparation, honey harvesting, game hunting, pasture improvement burning, and charcoal burning (NBSAP, 2015). Other threats are illicit fishing, deforestation, illegal hunting and logging, mineral and aggregate mining, unplanned human settlement developments, agriculture, grazing and livestock migration, water quality degradation and cultural beliefs (6th National Report, 2019). Especially poaching and unrestricted legal hunting have resulted in overexploitation of wildlife. (Kideghesho, Mwamende & Selemani, 2013). Due to Tanzania’s distinctive species and fairly well-developed transportation infrastructure, it has emerged as a key destination for wildlife trafficking. As a result, well-armed poachers and well-organized trafficking networks have annihilated populations of rhinos, pangolins, big cats and elephants.

Moreover, local villages are pushed to over exploit their resources for living, as natural resource management strategies for livelihoods are generally unsustainable and not efficient (USAID, 2001). In many parts of the country, agricultural growth is a major contributor to habitat fragmentation and biodiversity loss; there is a growing demand for grazing areas and livestock feed as well as crop production. The number of goats and cattle grew tremendously in recent years. The expansion of agricultural and grazing land, along with unsustainable agricultural methods, has resulted in fragmentation of natural ecosystems, increasing biodiversity challenges (NBSAP, 2015).

Further, the decline of marine and coastal living resources, the devastation of coral reefs, coastal contamination, and erosion are the primary challenges to marine and coastal ecosystems. Destructive fishing activities account for much of the destruction of reef ecosystems. The usage of dynamite, which has been used in some areas of Tanzania for almost 40 years, is the most harmful fishing method. Every explosion instantaneously kills all fish and most other living organisms within a 15-to-20-meter radius, as well as entirely destroying the reef ecosystem (6th National Report, 2019). The destruction to coral reef structures is severe and mostly irreversible. Nevertheless, dynamite fishing has decreased across the country as a consequence of public awareness, increased regulation enforcement, and the formation of a Multi-Agency Task Team, which combats environmental and wildlife crime, among other things. However, small mesh seine nets used to catch fish on the bottom and around reefs are nearly as destructive as explosives (6th National Report, 2019). A lack of employment opportunities and education, poverty and rising demand for shellfish and fish work against incentives for using more sustainable fishing practices (Torell et al., 2007).

Additionally, over-harvesting of mangrove for firewood, construction poles, charcoal, and boat construction, which account for about 46 percent of mangrove forest degradation, while clear-cutting of mangrove for agriculture, hotel building, urbanization, solar salt production, and road construction account for another 30 percent. Rising demand and prices for mangrove charcoal and firewood from Zanzibar and Dar es Salaam will encourage even more people to participate in mangrove harvesting (Torell et al., 2007).

Furthermore, climate change, pests and diseases, and incorrect agro-chemical use harm pollinators and other important non-target organisms, putting biodiversity in the agricultural ecosystem at jeopardy. Climate change has an impact on nearly all ecosystems in Tanzania. Likewise, improper disposal of industrial and household waste on land and water bodies are polluting surface and groundwater supplies (6th National Report, 2019). The increasing reliance on artificial fertilizers and chemical sprays for farming, also close to rivers, is another significant issue (Torell et al., 2007). Substantial amounts of nutrients, mostly phosphates and nitrates, are present in most aquatic ecosystems as a result of household, industrial, and agricultural activities. Toxic substances from industries and mining activities, agricultural herbicides and pesticides, and sewage-effluent find their way into aquatic systems, and the majority of them are hazardous to wildlife and can cause long term damage (NBSAP, 2015).

Population growth is another factor for biodiversity loss. Tanzania's population climbed from 12.3 million in 1967 to 44.9 million in 2012 and is expected to reach 59.8 million by 2025. The majority of people in rural areas rely on subsistence agriculture for food and money, which leads to unsustainable resource extraction and habitat degradation, culminating in biodiversity loss (NBSAP, 2015).

Trends in Biodiversity

Tanzania has been a member of the Convention on Biological Diversity since 1996, and it is committed to upholding its international commitment to safeguard and maintain its biodiversity as a global resource. It is essential that the country protects its biodiversity, and it has taken a variety of steps to do so. The updated National Biodiversity Strategy and Action Plan (NBSAP) (2015-2020) of the government aims to address national targets built on objectives that contribute to global goals. Tanzania also acknowledges the need to develop new policies in response to new and emerging policy challenges, as well as the need to assess and improve the execution of current policies, plans, and strategies (SCBD, n.d.). About 40 percent of the total terrestrial land is already under protection. According to the 2009 nationwide elephant census, elephant populations in protected regions like Tarangire-Manyara and Serengeti increased by 64 percent, correspondingly. Nature parks and reserves have been established for the purpose of developing and administering nature reserves in Zanzibar. The Chumbe Island Coral Park Reef Sanctuary has been designated as one of the most diversified regions, with 90 percent of East Africa's hard coral species estimated to be found there (NBSAP, 2015). Several antelopes of the severely endangered Ader's duiker antelope and a huge population of the Coconut crab, as well as numerous endangered bird species, can be found in the Closed Forest Habitat. The East Africa Marine Ecoregion recognizes Jozani National Park as home to at least 291 vascular plant species from 83 families, 28 of which are indigenous, and 21 species that are vulnerable or endangered. The national park is also home to a diverse range of animals, both terrestrial and marine species, many of which are rare and endangered, including the Zanzibar leopard and the Zanzibar red Colobus monkey (NBSAP, 2015).

[...]

¹ Silvicultural treatments are applied to trees and stands to change, accelerate, or maintain their condition (https://www.nrs.fs.fed.us/fmg/nfmg/fm101/silv/p2_treatment.html, as of 03.07.2021)