Outline of Hypnea (1999) Course
INTRODUCTION Definition and meaning, guiding principles, economics/ politics/education, World conservation strategies.
THE ISSUES Human expectations, human pressures, exploitation (habitats & species), interdependence, extinction.
BIODIVERSITY AND RARITY
Within and between geographical habitats; taxonomic status; species packing and turnover, endemism - islands, relicts, anthropogenic effects.
FITNESS AND VIABILITY Maintenance of small isolated populations, deterministic and stochastic extinctions.
COMMUNITY PROCESSES
Limited membership; mutually co-dependant assemblages; biocontrol; expert systems.
SENSITIVE HABITATS
Tropics, mountain areas, wetlands, social values and issues, conservation, development and greed; understanding of traditional practices.
MANAGEMENT
Management practices. Use of fire in management. Adaptive management. IEM process.
BIOGEOGRAPHY, PATCHES & FRAGMENTATION
Surface area to volume; edge threats and benefits; guidelines for reserve selection and management, immigration and extinction rates.
PROTECTED AREAS AND CONSERVATION PRACTICES
Conservation = maintenance of biological processes, harnessed for sustainable (?) utilization by people.
RESTORATION
Flexibility essential, restoration, reclamation and regeneration of ecosystems (e.g. desertification); damaged ecosytems and their use/misuse.
ECOTOURISM
Putting value on natural resources. Potential of ecotourism.
GREEN POLITICS
Putting environmental sustainability on the political agenda and incorporating environmental expertise into national and international policy.
PRACTICAL THEME- MAPPING AND MANAGING RESOURCES
Understanding maps and GIS. Introduction to remote sensing and field collection of spatial data.
APPLICATION AND COURSE PROJECT
Planning, developing and managing the False Bay Coastal Park and to present results as a web page.
Introduction
Conservation biology is a mission orientated discipline comprising both pure and applied science (conservation defined)
The breadth of conservation biology is as broad as biology itself. Traditionally it focuses the knowledge and tools of all biological disciplines - from molecular biology to population biology into one issue.
Conservation biology’s integrative nature makes it one of the most challenging fields, limited by the capacity of its mangers. It is neither a pure nor an applied field but its effectiveness is based on its originality and like other field its scientific rigour.
People have been responsible for extinctions for thousands of years such as the large mammal fauna of the Americas, which followed human colonization from Asia about 11 000 years ago. Aristotle in the Greek period commented on the widespread destruction of the Baltic forests. At the same time the forests of southern Asia were being felled to meet the burgeoning ship industry that was vital for the developing trade markets (the arid lands of Turkey, Syria, Iraq and Iran are the result of massive exploitation of fragile woodlands). Even Italy and Greece were formerly far more heavily wooded than they are today.
People have sought to protect wildlife for > 2000 years. For example the local chief Sakhile in Transkei decreed that local forests around Dwesa were royal and forbade hunting in them. Formalized philosophies of conservation biology developed into two branches during the 19th century with preservationists wanting pure wilderness based on a spiritual appreciation for nature and the conservationists advocating a resource-based approach to the management of natural resources. It was the publication of Aldo Leopold’s “A Sand County Almanac” in 1949 that a third philosophy within conservation biology was borne, that of Ecological Land Ethic. This philosophy articulated that complicated and integrated systems of integrated processes and components existed in fashion similar to a “fine Swiss watch”. Leopold saw ecosystems existing within equilibriums, a view subsequently replaced by non-equilibrium views. Even today the science of conservation is still developing since it has been marred by past academic prejudice, which has left its development as a discipline to wildlife managers, foresters and field biologists. Fortunately biology student and biological courses today are not asking whether they should be conservationist in the approach but rather how you can adopt this approach.
Three guiding principles for Conservation Biology have emerged
Principle 1: Evolutionary Change. This is based on the population geneticist Theodosius Dobzhansky who stated, “nothing in biology makes sense except in the light of evolution”. Evolution is the most plausible explanation for the immense pattern of biology diversity that exist on the planet and consequently the genetic composition of organisms is continuously changing whether due to factors of isolation existing within small and or isolated populations, immigrations from other populations or natural selection itself. Consequently the goal of this principle is to allow populations to change in response to environmental changes through adaptations.
Principle 2: Dynamic Ecology. Views the ecological world as dynamic and largely functioning through non-equilibrium principles. It specifically rejects the equilibrium viewpoint, which defines stable end points such as climax communities and other concepts such as the “balance of nature”. This view sees the regulation of ecological structure as not being maintained through internally generated processes (e.g. ecological pyramids and the transfer of energy through food chains) but through external processes, in the form of natural processes such as fires, floods, droughts, storms, earth moving, outbreaks of disease and or parasites as the overriding factors. We know that non-equilibrium processes maintain almost all ecosystems e.g. fire in fynbos. Consequently ecosystems consist of patches and mosaics of habitats that not internally uniform with clearly defined species assemblages, and that internal composition change in response to disturbances. Nevertheless this non-equilibrium viewpoint does not suggest that species interactions are ephemeral or totally unpredictable and that integral to communities are clusters of species that have strong interactions that are legacies of long periods of co-existence. The critical focus of this principle is the integration of non-equilibrium processes within a hierarchy of species interactions and recognizes that ecosystems are open with fluxes of species, materials and energy.
Principle 3: The Human Presence. Humans are participants within both natural and perturbed ecosystems and presence within ecosystems needs to be recognized and accounted for. Conservation efforts cannot wall off nature to safe guard it from humans since ecosystems must be seen are open systems and nature reserves inevitable exist within a surrounding landscape that is intensively utilized by humans. This principle explicitly integrates humans into conservation practice. For example indigenous local knowledge can be integrated into the formulation of conservation practice, local residents can be employed within the management and education functions of nature reserves. Ultimately reserves need to be “user friendly” to gain and maintain public support. Native human cultures forms historical components to the landscape and must be explicitly recognized as a form of diversity in the same way that biodiversity is. Many traditional societies have developed sustainable models of existence that can serve as models for modern sustainable development.
Economics as a discipline are strictly speaking external influences within the field of Conservation Biology. However, certain principles of economic theory are required when acquiring and managing funds for scientific research and acquisition of land for conservation practices. Increasingly nature conservation can be seen as a form of land use and its value for generating capital through tourism is compared to other economic activities. As human society’s become increasingly capitalistic in their structures so do their need to put value of natural resources. The development of environmental audits using species and habitats as the foci is still in its infancy. Defining the value for a global society of a Panda or Blue Whale will be debated well into the next millennium. Nevertheless growing leisure and tourism industries will put increasing value to living resources exiting in their natural habitats and will become integral to the economies of many third world nations!
It is naïve that Conservation Biology should be apolitical despite the fact that it should be for all people. Inevitably the only realistic paths to sustainable conservation are through the provision of a reasonable standard of living for all people. This will require greater equity between the “haves” and “have-nots” and is only achievable through political systems that encourage some people to accept lower standards of living so that others may escape the effects of desperate poverty. Conservation also needs the support of party politicians at local, regional and national level, which inevitably requires that conservation biologists will need to invest time to lobbying and education. The relationships between unequal access to resources, unsustainable of development generally, and the loss of biodiversity in particular were major themes of the United Nations Conference on Environment and Development held in Rio de Janeiro in June 1992. Since they have more to lose people and politicians from the developed northern industrialized nations have had difficulty in participating in this discourse, and even greater difficulty participating in the design of global institutions to address the roles of inequality in environmental degradation.
Education is the means by which conservation is transferred from economic theory into social practice. For conservation to work people must want it rather than have it imposed upon them. To want and believe in conservation principles means to understand and appreciate the inter-relatedness of humans and their societies with their biological and natural environments. The University of the Western Cape must be almost unique among Southern African higher education institutions in that conservation is explicitly recognized within its mission statement and is one of only two campuses that have officially recognized Nature Reserves (University of Port Elizabeth being the other). UWC is also fortunate in having an Environmental Education and Resource Unit, which undertakes many outreach programmes for local communities.
People’s realization of their roles in determining their future on earth prompted the development in the 1980’s of the World Conservation Strategy.
The surface of the earth is undergoing many human-imposed changes that match the upheavals of Pleistocene glaciations. Evolution is measured on a geological time scale of millions of years, however today changes such a as increasing temperatures and a doubling of CO2 levels in the atmosphere are occurring within decades.
Human expectations are a decent standard of living, which includes, food, shelter and water, space, education and a freedom of choice.
Human pressure is a global problem arising from population growth. By 2110 + 10.5 X 10-9 people will exist which is double that of the present world population. Of these 9.1 X 10-9 will be living in the developing nations of the world which are the most impoverished and where the most amount of damage to the natural environment will occur and where there is greatest biodiversity. For example Kenya will increase from 17 million in 1980 to 109 million in 2095 and Columbia increasing from 27 million to 60 million in the same period. Many countries that a few years were self-sufficient in food now have to import food (e.g. Namibia).
Hungry and dissatisfied people do not always make the best use of their living space. They tend to make extensive rather than intensive use of the land and techniques that could improve the situation are generally unavailable or beyond local budgets (e.g. inorganic fertilizers, high yield seeds and mechanized methods. Wastefulness is not the preserve of the poor and wealthy first-world society is even more wasteful especially with respect to energy utilization and their industries have had greater impacts on upsetting global atmospheric patterns. In many developing countries large tracts of land are cleared to provide exports to these wealthy countries. The Brazilian forest has been converted to cattle ranching to provide beef for the North American fast food industry. Fisheries industries of developing countries have collapsed due to local exploitation of the resources for export to the wealthy nations.
Over exploitation and utilization leads to threats of habitat destruction and species extinction. Tropical forests have 50% of the world-estimated biodiversity. Yet we know little of the structure and functioning of such systems. It was only in 1972 that the Tasaday tribe in the Philippines was discovered only 24 kms from the outside world, yet these people had been isolated since Neolithic times. The loss of tropical forest is serious with estimates of 700 kms2 being seriously short of the loss that occurred from fires during 1997/1998 in southeast Asia. Other ecosystems under threats are wetlands (considered to be the most threatened in South Africa), coastal areas, arid and semi-arid rangelands, the latter being particularly vulnerable ecosystems since they are event driven.
Conservation History and Ethics:-
The inaugural issue of Conservation Ecology:-
Introduction to Conservation Biology and Biogeography:-
Human Population Growth:-
Conservation Biology – The Major Issues
Essentially human pressures on the biosphere are causing “ problems” - changes, some of which we understand and many of which we don’t and still others will remain unperceived and/or immeasurable.
Both human expectations and pressures have been discussed with the inefficient utilization of resources that threaten habitat with destruction and species with extinction.
Interdependence of organism is one of the critical issues if trophic cascades are to be avoided. Since the biosphere is comprised of a web of biologically linked process all of which are dependant on one another and link the biotic with the abiotic systems. See the section on species interactions which include competition, commensalisms, predation, parasitism, mutualism and herbivory. Mutualism is an obligate interaction the absence of which causes depression and even extinction of either or more usually both partners in the association. Common examples are lichens (algae and fungi) and symbiotic nitrogen fixing bacteria and fungi, which live in association with the rooting systems of vascular plants. In this example N2 is converted to NH3 undertaken by prokaryotic organisms in association with eukaryotic organisms, the prokaryotic organisms benefit with the supply of sugars and the eukaryotic organisms with the supply of sugars(e.g. Rhizobium in the Fabaceae family).pollination (sunbirds and ericas or bees and fruit orchids) and seed dispersal processes (ants and the elaisomes of certain fynbos plants). Herbivory is where animals consume plants and was historically considered to be examples of negative interactions but today are seen as beneficial since they even out competition between species and reduce the potential of one or a few species becoming dominant. Herbivory has alternatively been considered to include two systems which include Saprophages which include detritovores which are consumers of dead plant parts and biophages which are consumes of living organic material. Within the category biophages includes predators, which consume plants, animals and their propagules as entire entities, parasites with in effect are micro-predators whose combined effect can kill their host and browsers and grazers who are consumers of vegetative parts of plants. Plants often show responses to herbivory such as secondary compounds, spines, schlerophyllous leaves or silicates in grasses.
Extinction is the failure of a species as a population to maintain itself through reproduction. Extinction occurs when the last individual has died/or when the remaining individuals are incapable of producing viable and fertile offspring. The concept of extinction is important, but more important is to focus on the process. Extinctions are part of ongoing biological processes and factors that contribute to extinction are
Biotic factors:
Competition
Predation
Parasitism
Disease
Isolation
Habitat change:
Geological changes
Climate
Catastrophes (e.g. dinosaurs)
Man induced activities (e.g. quaternary extinctions and current extinctions)
Glossary
Biodiversity Glossary of Terms:-
Out of Date
Biodiversity and Rarity
OBJECTIVES
To understand the importance of biodiversity for ecological management and to identify where there are areas of high biodiversity both globally and nationally. To discuss what the state of the art for biodiversity research in southern Africa. Evaluate the concept of keystone species and discuss the process of extinction. Discuss how you can measure biodiversity and define alpha, beta and gamma diversity. Discuss why tropical areas are so diverse Understand why there are limits to species distributions.
VIEWPOINT
Diversity and rarity are synonyms for virtually everything in ecology. In effect if ecologist can explain and predict the patterns of diversity and rarity in communities it means that they have understood and quantified the distribution and abundance patterns of the community’s component species, a situation that rarely if ever occurs!
The concepts of diversity and rarity are consequently fundamental to much of conservation decision making and consequently when biologists working on different taxa and using different approaches have convergent results it is impressive. Rarity is divided into three components namely
1. Within habitat
2. Between habitat
3. Geographic
One of the major sources of complexity in the analysis of rarity is the sample or scale of the problem (the smaller the sample the more rare the species is one case). Endemism is a scale dependent concept. Discuss political endemism (rare in one political state but common in another political state. The concept of endemism at the global scale is meaningless since every species is endemic to the planet earth. One other approach to rarity is the taxonomic one, one taxa in a genus, family or order is a useful index for describing uniqueness. Rarity has been measured at one trophic level but ideally it should be measured at the community level and across trophic levels. Need to develop techniques to identify patterns and relate biological specialization with abundance. The robustness of such techniques is tested by their ability to be predictive. The other problem with rarity is that it’s a sampling intensity concept. The more that you sample an area the greater the amount of realized biodiversity and the greater the chance of report an endemic or rare species. For this reason we need to develop techniques that provide equitable probability or reporting rarity or endemism. Using remote-sensing techniques and various landscape indices is one avenue of research. Another approach is to set up rule-based decision analysis or expert systems. This uses prior or known information on which to develop rules from which the system is applied to new cases. For example one rule might be that generalist species are more widespread and common and therefore are not useful for defining conservation areas. From this line of research are the iterative techniques