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23.1: The Science of Conservation Biology

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    Figure \(\PageIndex{1}\): East Africa’s great migration is one of the most famous wildlife spectacles on Earth. Each year, tens of thousands of tourists from around the world flock to the region to see the 1.7 million common wildebeest (Connochaetes taurinus, LC) and hundreds of thousands of other plains mammals make their way from Tanzania’s Ngorongoro Conservation Area, through the Serengeti Plains, to Kenya’s Maasai Mara National Reserve. "Wildebeest Migration in Serengeti National Park, Tanzania" by Daniel Rosengren is licensed under CC BY 4.0. 

    Popular interest in protecting biological diversity—which describes the amazing range of species, genetic diversity within each species, and the multitude of Earth’s complex biological communities with their associated ecosystem processes—has intensified during the past few decades. During this time, scientists and the public have recognized that biological diversity (often shortened to biodiversity) is being lost at increasing rates. Across the world, human activities are destroying ecological communities that have developed over millions of years. Over the next several decades, thousands of species and millions of populations will likely go extinct.

    The fundamental driver of all the biodiversity losses we are currently witnessing is a rapidly expanding human population coupled with increased consumptive needs. In 1850, after roughly 300,000 years of Homo sapiens on the planet, there were around 1 billion people on Earth. By 1987, not even 140 years later, the world’s human population had surpassed 5 billion. By 2017, there were 7.5 billion humans globally, of which over 1 billion lived in Sub-Saharan Africa (World Bank, 2019). With this many people, the human population grows by tens of millions of people each year, even with modest population growth Figure \(\PageIndex{2}\) . To make matters worse, Sub-Saharan Africa has the fastest population growth rate in the world, with a projected human population estimate of over 4 billion people by the year 2100—a number that is well beyond the ecological capacity of the region to support.

    A bar graph shows the human population growing from 0.1 billion in 1700, to 0.2 billion in 1950, to 0.7 in 2000, and to an estimated 2.2 billion by 2050.

    Figure \(\PageIndex{2}\): Sub-Saharan Africa’s human population crossed the 1 billion mark in 2015. At the current annual population growth rate of 2.7%, more than 28 million people will be added to the region in 2019. This number will escalate each subsequent year as increases are compounded. Sources: Biraben, 2003; World Bank, 2019, CC BY 4.0. 

    To survive and prosper, people use natural resources. They harvest and use oil, water, and wildlife products, and convert natural ecosystems for agriculture, cities, roads, and industrial activities. This consumption, which reduces natural habitat and the associated wildlife populations, is intensifying because of the demands of a rapidly increasing human population. Consumption of resources also increases as countries develop and industrialize: the average citizen of the USA uses five times more resources than the average global citizen, 11 times more than the average Chinese citizen, and 32 times more than the average Kenyan citizen (Worldwatch Institute, 2015). This growth in the number of humans, together with their ever-more-intensive use of natural resources, is the fundamental driver behind most current species extinctions.

    For conservation biologists and other nature lovers, the widespread extinction of species and destruction of natural ecosystems are incredibly discouraging.

    Conservation Biology as a Discipline

    As a distinct scientific field, conservation biology is an integrated, multidisciplinary subject that developed in response to the challenge of preserving populations, species, ecosystems, and biological interactions. The main aim of conservation biology is to ensure the long-term preservation of biodiversity. To achieve its aim, conservation biology has set three goals:

    • To document Earth’s biological diversity.
    • To investigate how humans influence species, evolution, and ecosystem processes.
    • To investigate practical approaches to protect and restore biological communities, maintain genetic diversity, and prevent the extinction of species.

    The first two goals describe typical scientific research investigating objective facts. The third goal, however, is a part of what makes conservation biology a normative discipline; that is, conservation biology incorporates human values, not just facts, to understand and achieve its value-laden goals (Lindenmayer and Hunter, 2010). In this sense, conservation biology is related to environmentalism, in which people aim to protect the natural environment for its own sake. However, conservation biology is at its core a scientific discipline; it is founded on scientific principles. This is not to say you must be a scientist to practice conservation biology; there are many people who are not scientists who apply the principles of conservation biology in their professional and personal lives.

    The emergence of conservation biology as a distinct scientific field in the 1970s has given rise to the formation of various formal societies representing the field in a united voice. Most notable among these is the Society for Conservation Biology (SCB, Figure \(\PageIndex{3}\)), which is a non-profit international professional organization with a mission to advance “the science and practice of conserving the Earth’s biological diversity”. To facilitate opportunities where like-minded people can share ideas locally, the SCB has regional branches, including an active Africa Section ( which hosts regular conferences. In addition to the SCB, a great number of other local, national, and regional conservation organizations also exist and act as mouthpieces for grassroots movements and as custodians of nature. Many of these groups focus on specific animals or local protected areas. Others organically adapt their missions and visions in response to a specific need or threat. For example, established in 1913 as an exchange forum between collectors of rare plants, the Botanical Society of South Africa now actively works toward protecting those rare plants in their natural habitats.

    The logo for the Society for Conservation Biology is shown, represented by a circle enclosing a wave, with a bird head and leaf wings.

    Figure \(\PageIndex{3}\):  The logo of the Society for Conservation Biology (SCB) has several layers of symbolism. Enclosed in the circle of life are ocean waves, representing change. The bird symbolises beauty, and the leaves (the bird’s wings) remind us of nature’s productivity. Image courtesy of SCB, all rights reserved.

    In recent years, conservation practice has evolved from just a plan to save the environment to a vision that includes sustainable development and social justice.

    Conservation biology also has a history of adapting to new challenges. The very first conservation activities, in Africa and beyond, were geared towards securing the rights to valuable natural resources for people in powerful positions, such as kings and tribal chiefs, enforced through a strictly adherence to cultural norms and customary laws. But as a growing human population expanded its influence on the environment, and wildlife started to decline, earliest conservation models gradually shifted towards fortress conservation approaches (Wilshusen et al., 2002) which aimed to shield wildlife from people by setting aside protected areas where human activities were strictly controlled.

    Today, however, as human populations are exploding, and consumption is increasing, even protected areas are increasingly unable to withstand the multitude of threats to biodiversity that ignore property boundaries and political borders. In response, fortress conservation approaches are beginning to make way for large-scale integrated activities that highlight the social and economic benefits of biodiversity conservation. To do this, new alliances are being formed and new agendas are being established, such as those that directly link human health with environmental health (Box \(\PageIndex{1}\)). These integrated conservation philosophies that pursue strategies that benefit both humans and biodiversity show much promise because they focus on fundamental extinction drivers, and advocate for more inclusive sustainable development. In this way, the practice of conservation has evolved from just a plan to save the environment to a vision that accomplishes its goals through sustainable development and social justice.

    Yet, as we consider how to best invest limited conservation resources, some difficult questions arise. With seemingly more work to be done than can be accomplished, should we let some species go extinct (Bottrill et al., 2008)? Which species? Who decides? How can we even dare to think that we can play god? Such questions predictably bring about strongly opinionated and emotional debate (Soulé, 2013 vs. Marvier, 2014; Tallis and Lubchenco, 2014). Given the successful track record of fortress conservation initiatives in preventing extinctions despite limited budgets (Young et al., 2014), as well as the promising progress of more complex people-centred initiatives (Pooley et al., 2014), it seems clear that conservation relies on some balance between these two conservation philosophies (Sodhi et al., 2011). Conservation biologists of tomorrow will be able to fine-tune the balance between these strategies by closely inspecting the successes and failures of our actions today.

    Box \(\PageIndex{1}\) Conservation Through Public Health: A Case Study

    Gladys Kalema-Zikusoka

    Conservation Through Public Health,

    Kampala, Uganda.

    Conservation Through Public Health (CTPH) is a grassroots non-governmental organization (NGO) and non-profit that promotes biodiversity conservation by enabling people, wildlife, and livestock to coexist. The organization was founded in 2003 after fatal scabies skin disease outbreaks in mountain gorillas (Gorilla beringei beringei, EN) were traced to people living around Bwindi Impenetrable National Park, Uganda, who had limited access to basic health services (Kalema-Zikusoka et al., 2002). Since then, CTPH has contributed to conservation and sustainable development in Africa by improving human and animal health and welfare in and around protected areas.

    One of the main goals of CTPH is to reduce disease transfer between humans and gorillas. We accomplish this through an integrated population, health, and environment (PHE) program that was established in 2007 with funding from the US Agency for International Development (USAID). As a first step, piloted around Bwindi, CTPH held consultative meetings with local leaders, during which at least one Village Health and Conservation Team (VHCT) volunteer was selected from each village and two from each parish (consisting of 11 villages) to oversee distribution of family planning supplies. This initiative rapidly expanded into a sustainable social service delivery network that promotes family planning, hygiene, and sanitation. The network resulted in a 20% to 60% (national average is 30%) increase in new users to modern family planning, and a 10% to 60% increase in adoption of hand washing facilities at homes visited by VHCTs. VHCT volunteers also refer people suffering from infectious diseases and malnutrition to local health centres and promote more sustainable alternative livelihoods. Another group of community volunteers, the “Human and Gorilla Conflict Resolution” (HUGO) team, in turn collect gorilla faecal samples left on communal land to monitor their health Figure \(\PageIndex{4}\), and visually monitor gorillas for clinical signs of disease inside and outside protected areas (Gaffikin and Kalema-Zikusoka, 2010). In the process, we have seen reduced disease incidences in the gorillas, reduced conflict between people and gorillas, and improved attitudes toward conservation. One unintended outcome has been increased gender equality: men are now more involved in family planning, and women are more involved in natural resource management.

    A Ugandan park ranger in a green uniform and hat with medical gloves stands in a densely vegetated area and demonstrated to another man wearing a pink shirt and medical gloves how to use a sampling tool.

    Figure \(\PageIndex{4}\): A park ranger from the Uganda Wildlife Authority teaching HUGO community volunteers how to collect faecal samples from gorilla night nests during a CTPH training workshop. Photograph by CTPH, CC BY 4.0.

    Our experience in initiating and managing PHE programs for the past 10 years has taught us several lessons. One of the most important lessons to ensure project sustainability is to regularly engage with local leaders and the government. The Uganda Wildlife Authority, Uganda’s Ministry of Health, and local health centres all attend CTPH meetings with VHCTs. Attendance by and representation of these groups not only informs them of our activities, but also provides a platform to inform or train the VHCTs in what they would like them to disseminate to the local communities.

    We have also learnt that PHE-implementing partners and projects need to be well-suited to each other and each site; this remains true even though health needs are often the same, regardless of the location. For example, at Mount Elgon National Park in Uganda, we found that training VHCTs in reducing conflict with park management played a key role in changing community attitudes toward conservation. In contrast, at Virunga National Park, Democratic Republic of the Congo (DRC), we found that VHCTs needed to work more closely with local health centres to prevent disease transmission between people and gorillas, and to promote family planning in a largely Catholic country.

    Lastly, we found that establishing income-generating projects for groups rather than individuals was key to sustaining VHCT networks and program goals beyond donor funding cycles where we have had no volunteer dropouts in the first 10 years of initiating the PHE program. These key components were accomplished by initiating livestock group enterprises and by encouraging VHCT volunteers to invest generated income into Village Saving and Loan Associations (see

    The Role of Conservation Biologists

    While there are a few extinctions that have only one cause, more generally, extinctions occur because several factors acted simultaneously and/or sequentially. Blaming a certain industry or specific group of people for an extinction (or other biodiversity loss) is thus simplistic, ineffective, and often counter-productive. Though challenging, a better approach would be to better understand how local, national, and international links led to those losses, and to find viable alternatives to prevent it from happening again. To succeed in this challenge, conservation biologists should strongly consider taking on one or more of several roles:

    • Conservation biologists should be curious. The world around us is full of natural wonders waiting to be discovered. These discoveries underpin conservation action, by allowing us to define all the different components of biodiversity, enabling us to better understand the needs of different species, and providing us with opportunities to celebrate our conservation successes.
    • Conservation biologists must be good listeners. Sometimes, the only difference between attracting a new ally and making an enemy, or between developing a landscape and saving a species from extinction, is the way we communicate. Conservationists must be careful and respectful listeners, especially to opposing perspectives. Careful listening is particularly important in rural areas, where villagers often have practical concerns related to their daily contact with wildlife, such as staying safe and preventing crop damage and livestock loss. Quite often, those villagers may also have unique insights into wildlife ecology that could prove valuable in local conservation measures.
    • Conservation biologists must be law-abiding citizens. Activities that involve wildlife and ecosystems are regulated by laws and regulations. These laws are important because ethical boundaries differ from person to person—activities acceptable to one group of people may be considered harmful by another. As conservation biologists, abiding by environmental laws is especially important if we want others to take those laws seriously.

      Laws are important because ethical boundaries differ from person to person—activities acceptable to one person may be immensely harmful to another.

    • Conservation biologists should become effective communicators. They should be able to discuss the problems facing biodiversity in depth, as well as the consequences of losing biodiversity, to as broad a range of people as possible. Groups like hunters, community leaders and organisers, and church leaders may be interested in participating in conservation efforts once they recognize that their activities, health, and emotional well-being depend on conservation action.
    • Conservation biologists could become politically active leaders, so that they can influence public opinion and policy. As a starting point, those interested in this role can join a conservation organization to learn more about broader issues. They could also use their personal networks to form alliances with lawyers, citizen groups, and politicians.
    • Conservation biologists could become pro-active land managers. Those taking on this task must be willing to walk on the land and go out on the water to find out what is really happening. They should also talk with local people to communicate their knowledge to others in ways that are clear and easily understood.
    • Above all, a conservation biologist must be honest. To encourage effective action, both from the public and through policy, conservationists must present arguments backed by reliable evidence. To do otherwise, conservation biologists could lose credibility, which would very likely delay or even compromise conservation efforts.

    It is worth taking a moment to distinguish between two important pillars of conservation action, namely conservation advocacy and conservation science. Conservation advocacy describes the roles that conservation biologists adopt to guide social, political, and economical systems towards a personally-preferred outcome—adopting environmentally-friendly practices; incorporating these activities makes conservation biology a normative discipline. Conservation science, in contrast, describes activities that conservation biologists undertake to generate knowledge, like objectively describing biodiversity and measuring biodiversity’s response to stressors and safeguards. While conservation advocacy and conservation science often support and inform each other as to the next steps required for “doing conservation”, it is important to distinguish between these two pillars to ensure that policymakers and other stakeholders in the environment understand when we advocate for personal preferences and when we offer objective findings (Rykiel, 2001; Lackey, 2007; Nelson and Vucetich, 2009). The next section will further expand on the importance of science in conservation biology.

    The Importance of Scientific Methods

    The field of conservation biology applies scientific methods to achieve its goals. Like the medical sciences, which apply principles from physiology, anatomy, and genetics to problems of human health, conservation biologists solve biodiversity problems using principles from fields, such as mathematics, veterinary medicine, social sciences, and several natural sciences (Figure  \(\PageIndex{5}\)). Conservation biology differs from these and other component disciplines in that its primary goal is the long-term preservation of biodiversity. Unlike many other scientific fields, conservation biology can also be described as a crisis discipline (Soulé, 1985; Kareiva and Marvier, 2012). That is, conservation biologists are often required to take creative steps to respond to imminent threats, typically without complete knowledge of the systems requiring attention. Conservation scientists must also articulate long-term visions for conservation beyond solving immediate problems.

    Arrows connect three boxes. One box labeled "Natural Resource Management" includes bulletpoints of agriculture, ecotourism, ethnobotany, fisheries management, forestry, hazard evaluation, land-use planning, rangeland, water, and wildlife management. A box labeled "Conservation Biology" includes behavioral ecology, biogeography, ecology, eco-philosophy, environmental monitoring, genetics, landscape ecology, physiology, population biology, taxonomy, and veterinary medicine. A last box labeled "Integrated Conservation and Development Projects" includes anthropology, climate adaptation, communications, economics, ethics, psychology, public health, public policy, social sciences, and sustainable development.

    Figure \(\PageIndex{5}\): Conservation biology draws from many other sciences to protect biodiversity. It is closely related to natural resource management, which aims to manage biodiversity primarily for the benefit of humans. Integrated conservation and development projects (ICDP) are projects that manage nature for the benefit of both humans and biodiversity. After Kareiva and Marvier, 2012; Temple, 1991, CC BY 4.0.

    To be effective, conservation biologists must demonstrate the relevance of their findings to a range of stakeholders. To be successful in this task, the importance of sound scientific principles cannot be over-emphasised. Nature is a complex network of many interdependent connections and feedback loops. Science is underpinned by principles that provide conservationists the necessary quantitative and qualitative tools to better measure and control for all these different aspects of biodiversity. Such measurements allow us to gain a better understanding of complex natural systems, and the consequences of human activities. Reliable, unbiased data obtained from sound and transparent scientific methods also facilitate policymaking that is too often based on value judgments by non-experts who must balance many needs and different sources of information (Ntshotsho et al., 2015).

    One of the cornerstones of modern science is to identify a hypothesis (a proposed explanation for a specific observation) to evaluate. The best hypotheses, often expressed as goals or objectives, are usually those that are SMART:

    Specific: not overly general
    Measurable: has both units and a method of measurement
    Attainable: realistic to achieve
    Relevant: related to what needs to be accomplished
    Time-bound: achievable within a specific timeframe

    Identifying SMART goals and objectives is an essential aspect of conservation biology. Without such benchmarks, practitioners cannot know whether their tasks were successful, or when management actions should be adjusted to achieve success. While this may seem obvious, many previous conservation projects have failed because biologists neglected to set SMART goals and objectives (Tear et al., 2005). While lofty, “We’re going to save all species” is not a SMART conservation goal because it is overly general, hard to measure, unrealistic, and not time-bound. In contrast, “We want to protect 25% of our country’s wetlands within the next 10 years” is a SMART goal because it sets a very clear and measurable objective. In general, it is wise to set smaller short-term (e.g. quarterly), and medium-term (e.g. annual) goals as one works towards long-term (e.g. 5–10 years) objectives; this allows one to constantly assess progress, which in turn provides opportunities for celebrations and strategic adjustments as and when needed.

    Conservation biology’s ethical principles

    Conservation biology rests on a set of underlying ethical principles that is generally agreed upon (Soulé, 1985) and can be summarized as follows:

    • The diversity of species and biological communities should be preserved: Most people appreciate biodiversity. Hundreds of millions of people visit national parks, game reserves, zoos, botanical gardens, and aquaria each year. They spend money and take actions to protect these places and species. People also recognize that biodiversity has economic value, whether through tourism, consumption, or other services.
    • The untimely extinction of populations and species should be prevented: Throughout history, species have occasionally died off as a result of natural, non-human causes. The loss of a local population was generally temporary until a new population established itself through dispersal. However, human activities have increased the rate at which species are going extinct by more than a hundredfold. Meanwhile, there is no similar increase in the rate at which new populations and species are being created.
    • Ecological complexity should be maintained: In complex natural environments, biodiversity expresses many of its most valuable features and interactions. Although the biodiversity of species may be partially preserved in captivity, maintaining ecological complexity requires that natural areas be preserved.
    • Evolution should continue: Evolution creates new species, increases biodiversity over time, and facilitates adaptation to changing environmental conditions. People can help preserve these evolutionary processes by maintaining genetic diversity in wild populations and allowing populations to exchange genetic material. In captivity, many natural evolutionary processes do not occur, which can hamper survival when species are reintroduced in the wild.
    • Biodiversity has intrinsic value: The value of species, communities, and ecosystems does not depend on their utility to people. They are intrinsically valuable on their own, with unique evolutionary histories and ecological roles. There are certain iconic species that people simply want to have around, but other, lesser-known species or species seen as problematic to people are not less valuable.

    These principles are not absolute, nor are conservation biologists required to agree with them—they are actively discussed and debated. But many individuals and organizations agree with two, three, or all the principles, and support conservation efforts.

    Box \(\PageIndex{2}\) Biodiversity: Can Humanity be Saved?

    Nkengifor Nkeshia Valery, Regina International Cameroon, Member of Union Farms of Africa, Yaoundé, Cameroon.

    What happened over the past 200 years that we have arrived where we are? How did we get to this modern paradox? A society where we cherish comfort at the cost of the ever-increasing destruction of our planet. Never in the history of humanity has the environment been degraded to the point that even the air we breathe has become cancerous. Animals are exploited by industries at an alarming rate and those remaining are killed to enrich a privileged few. And all this evil happens with our complicity as indirect consumers. Our inheritance from God, the source of all our nourishment, does not belong to us. Yet it has been bought and exploited by multinational corporations and financial markets that hinder us from cultivating sustainably. We are pushed to feed ourselves and our crops with chemical products that are dangerous to our long-term health. We are also experiencing the start of the sixth mass extinction episode of biodiversity (Ceballos et al., 2017). As a result, the natural world has declared World War III against humanity. This is a war fought not by nation against nation, but that the environment has declared against the whole human race.

    This war condemns us to live in an illusion of freedom; we are, in fact, destroyed at an increasing rate by different dangerous diseases and rendered slaves of the polluted environments that we blindly accept. The question we need to ask is not whether we should act to save our planet, but what future and meaning we are going to give the word “HUMANITY”. We are all actors in a civilization that we are constructing; to quote the Indian leader Mahatma Gandhi: “If we could change ourselves, the tendencies in the world would also change. As a man changes his own nature, so does the attitude of the world change towards him. […] We need not wait to see what others do”. Let us pause and ask ourselves what we want the future to say of us. Are we a destructive generation, or a generation that is ready to sustainably preserve its biodiversity? It is a question every reader needs to ponder. The future is judging no one and blaming no one, but it needs us to change our habits towards protecting the world’s biodiversity.

    To change our attitude and make the world a better place, I drafted the following poem with passion to see my words become action for every lover of biodiversity


    We are a people of peace called forth out of humanity into restoring life to our natural habitat. We are governed and guided by a sense of sustainability. Conservation and protection is our priority in all things at all times we are led and driven by the spirit of an environment free of pollution we are called to effect and affect every life that we come in contact with towards the sustainable development of the environment​.

    We are called by humanity to be world changers we refuse to conform with the thinking pattern of the world system because we are world changers.

    Contributors and Attributions 

    Written and curated by A. Wilson and N. Gownaris (Gettysburg College) with material from the following open-access sources:

    23.1: The Science of Conservation Biology is shared under a CC BY-NC-SA 4.0 license and was authored, remixed, and/or curated by LibreTexts.