Chapter 1 conservation biology PDF

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Chapter 1: What Is Conservation Biology Environmental problems and human population growth

Large and rapid increase of human population has put incredible stress on planets biodiversity and natural systems which we rely on. Likelihood of outgrowing planets capacity However, some countries have shown it is possible to lower growth rates such as Cuba, Costa Rica and Germany Development and education lead to lower/smaller family sizes eventually Wealthy use a disproportionate share of global resources – reversible Conservation biology response to biodiversity crisis Challenging and imperative Synthetic field Encompasses biogeography, anthropology, philosophy, sociology, economics, population genetics and ecology for maintenance of biodiversity Crisis discipline Aiming to understand mechanisms of natural ecological systems Therefore better maintenance of biodiversity Human population growth has fragmented, simplified, homogenized and destroyed many ecosystems Aiming to maintain diversity (genes and populations), species habitats, ecosystems and landscapes Maintain natural processes such as natural selection, photosynthesis, energy transfer, biochemical cycling and hydrologic cycles. 1965, ecologists G. Evelyn Hutchinson compared the natural world to a theatre, saying it was the stage for an evolutionary play. To retain the actors in that evolutionary play and the ecological stage on which it is performed “New” conservation biology Recognises contributors from non-biologists – social science, economics and political science Management redirected towards stewardship Used to be more economically focused on utilitarian values Should change from reactive analysis to proactive science

A brief history of conservation biology

Globally conserving and protecting natural environment fairly recent activity Conserving economically important natural resources going on far longer Always thought that conservation is a western idea Many examples of natural resource management in other cultures “Dammar” agroforestry in Sumatra “Dammar” – Shorea javanica Plots structurally similar to natural successional plots Helps support regional biodiversity

Natural forest plots converted over 10-20 years Complex modified forest Accepted that with humankind comes destruction Increased rate of destruction due to significantly increasing population and therefore growing needs Diamond (1992) – anywhere that humans have colonised, environmental degradation and destruction occurs Many societies tried to reduce the negative impact they have had/are having on an environment Have a lasting impact on environment (destructive impact) Europe Conservation efforts mainly devoted to private game management and maintenance of Royal preserves and private manor land Little attention paid to commons/public land Led to their exploitation Europe mainly deforested by early 18th century Many forests in UK destroyed by 12th century – demand for charcoal Establishment of US Forest Service 1905 by President Theodore Roosevelt

Conservation in the United States

Aboriginal people Low population densities and lack of technology American Indians used fire extensively to manage land for agriculture and game Similar to conservation methods used today Colonial period Forest in North America exploited for lumber, ship masts, naval stores and charcoal Demand in Europe Domestic demand grew due to rapidly increasing population Theory of supply and demand Lumber needed for railroad and building construction Philosophy that nature’s bounty will never run out Forest not only economic resource Religious attitudes Puritans saw as abode of devil Wilderness seen as an evil place full of danger Romantic-Transcendental Conservation Ethic Ralph Waldo Emerson and Henry David Thoreau in east John Muir in west E and T argued nature’s anthropogenic value in 1800s Quasi-religious sense – temple to communicate with God Nature place to refresh and cleanse human soul John Muir – Sierra Club When people go to the mountains they are going home Resource Conservation Ethic Forester Gifford Pinchot in 20th Century

Based in popular utilitarian philosophy of John Stuart Mill “The greatest good of the greatest number for the longest time” 1947 Economically focused and would only conserve a species if it had an economic value “The first great fact about conservation is that it stands for development” 1947 Approach stresses equity – fair distribution of resources among consumers (in present and future) – almost sustainability? Multiple use concept Current mandate of U.S. Forest Service and Bureau of Land Management Multiple uses of land are attempted simultaneously For example, logging, grazing, wilderness preservation, recreation and watershed protection Government regulation needed to develop and enforce conservation policy Evolutionary-Ecological land ethic Aldo Leopold – A sand country almanac, 1949 States that nature is a complicated and integrated system of independent processes and components Equilibrium view Then replaced by dynamic, nonequilibrium ecological perspective

Modern Conservation Biology: A Synthesis

Balanced approach replacing extreme preservationist and exploitative utilitarian philosophies Ethical stewardship using natural and social sciences for theory and practise 1960s and 1970s obvious that pristine ecosystems disappearing rapidly Previous conservation efforts directed towards large vertebrates, soils and water Did not embrace intricacies of complex ecosystem function Overlooked “minor” biotic components such as insects, fungi and bacteria Attempts to rectify this in following years Publications Environmental Conservation, Raymond and Dasmann, 1959 Biological Conservation, David Ehrenfeld, 1970 Combined good evolutionary ecology with human resource conservation Conservation Biology: An Evolutionary-Ecological Perspective, Micheal Soulé and Bruce Wilcox, 1980 Conservation and Evolution, Frankel and Soulé, 1981 Genetics and Conservation: A Reference for Managing Wild Animals and Plant Populations, SchonewaldCox et al., 1983 Society for Conservation Biology formed in 1985 Started new journal called Conservation Biology Complemented Biological Conservation and The Journal of Wildlife Management

Guiding Principles for Conservation Biology

“The world view shared by scientific discipline or community” Kuhn 1972 “The family of theories that undergird a discipline” Pickett et al. 1992

Principle 1: Evolutionary Change “Nothing in biology makes sense except in the light of evolution” Theodosius Dobzhansky Unites all of biology Historical perspective on dynamics of life “Ground rules” for how living world operates Solutions to biological conservation problems must be considered and developed with an evolutionary framework – Meffe 1993 Genetic composition of populations most likely to change over time due to genetic drift of small populations, immigration from other populations and natural selection Aiming to conserve status quo, not stop genetic change Ensure that populations are able to respond to environmental change in an adaptive manner Principle 2: Dynamic Ecology Nature is dynamic Recognises ecological systems are not in equilibrium No stable point Regulation of ecological function and structure normally related to external pressures in form of natural disturbances such as fires, floods, droughts, storms, earth movement and outbreak of disease and parasites – not internally generated Ecological systems are open systems Fluxes of species, materials and energy Change is the universal feature of ecological communities Principle 3: The Human Presence Human’s part of natural and degraded ecological systems “Indigenous knowledge” used when developing reserve management plans “User-friendly” to build public support Allow limited public access to nature trails and develop educational programs Pride in natural heritage Aboriginal and tribal people Part of ecological landscape and have an ethical right to be there Bring different types of diversity – cultural and linguistic Some cultures developed sustainable methods of existence Now base for modern sustainable development Understand internal systems of values and knowledge of local natural resources – work with them Also incorporate modern cultures as they have largest influence Twin goals of biological conservation and sustainable economic development

Some Postulates of Conservation Biology

Cofounder of Society for Conservation Biology, Michael Soulé developed 4 postulates (1985) Help define ethical and philosophical foundations of conservation biology Diversity of organisms is good Biophilia Natural diversity good for well-being Extinction is bad

Ecological complexity is good “Expresses a preference for nature over artifice, for wilderness over garden” Simplification of ecosystems by humans is bad Evolution is good Bad to interfere with evolutionary patterns Biotic diversity has intrinsic value Regardless of utilitarian value Should not destruct diversity

Some characteristics of Conservation Biology

Crisis discipline Actions taken without complete knowledge Use available information with best intuition Must tolerate uncertainty Asked for advice by governments and private agencies on issues such as design of nature reserves, potential effects of introduced species, propagation of rare and endangered species and ecological effects of development Politically and economically charged Multidisciplinary Science Contributions from molecular genetics, biogeography, philosophy, landscape ecology, policy development, sociology, population biology and anthropology. Melding of “pure” fields of population biology and ecology with “applied” fields Strong philosophical input from social sciences Understanding of humanistic viewpoint Holistic field which involves entire ecosystems Cross-disciplinary perspective Conference in 1989 – cross-disciplinary breadth with disciplinary depth, field experience, communication skills and leadership skills Inexact science “Uncertainty is inherently part of ecology and conservation, and probabilistic, rather than prescriptive answers to problems are the norm” Include safety margins and recovery strategies Value-laden science Science supposed to be value-free, but because it is carried out by humans it is influence by opinions, goals and desires Mission-oriented Goal to conserve natural ecosystems and biological processes Scientists have responsibility to society for goal of biodiversity preservation Science with an evolutionary time scale Long-term validity of ecosystems and preservation of biodiversity Evolution is central concept in biology Science of eternal vigilance Protected areas not safe forever – repeatedly under pressure Conservation biologists must be continually protecting natural areas...