Term
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Definition
| Process of genetic change within a population due to natural selection, whereby the average state of a character becomes better suited to some feature of the environment. |
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Term
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Definition
| The practice of revisiting management decisions and revising them in the light of new information. |
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Term
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Definition
| A single reserve that is large enough to fulfill its conservation functions, or in a reserve system, a sufficient number or area of reserved sites to achieve conservation objectives. |
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Term
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Definition
| Land used for crops, pasture, and livestock; the adjacent uncultivated land that supports other vegetation and wildlife; and the associated atmosphere, the underlying soils, groundwater, and drainage networks. |
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Term
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Definition
| The phenomenon where at the point when population density is too low for individuals to find mates, reproductive success sharply declines. |
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Term
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Definition
| One of a pair of genes at a particular genetic locus. Different alleles are usually named for having a specific phenotypic affect (e.g., wild type versus mutant, albino versus normal, fine-spot versus large-spot). |
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Term
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Definition
| Describes two or more populations or species that occur in geographically separate areas. See also sympatric. |
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Term
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Definition
| One of several possible forms of an enzyme that is the product of a particular allele at a given gene locus. |
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Term
| alternative futures analysis |
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Definition
| A form of conservation planning where stakeholders and conservation biologists work together to propose and examine the consequences of distinct possible future states for an area, and use these projections as a basis for land use planning. |
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Term
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Definition
| The number of species occurring within a given habitat. |
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Term
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Definition
| Any human-oriented perspective of the environment, but usually used to emphasize a distinction between humans and nonhumans. For example, assessing a tropical forest in terms of its potential timber value is an exclusively anthropocentric perspective. |
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Term
| anthropogenic climate change |
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Definition
| The change in global, regional, and local climate as a result of human activities. Often referred to only as climate change or global warming. |
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Term
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Definition
| The ratio of internal area to edge habitat of a region. The area/perimeter ratio is an indication of the amount of interior habitat with respect to edge habitat, and may indicate potential success of a reserve in protecting interior species. |
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Term
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Definition
| Restoration undertaken to expand a site in area or quality. |
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Term
| background extinction rate |
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Definition
| Historical rates of extinction due to environmental causes not influenced by human activities, such as the rate of species going extinct because of long-term climate change. |
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Term
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Definition
| A branch of modern statistics that bases statistical inferences and decisions on a combination of information derived from observation or experiment and from prior knowledge or expert judgment. Contrast this approach with classical statistics, which regards only the data from observations or experiments as useful for estimation and inference. |
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Term
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Definition
| The change or turnover of species from one habitat to another. |
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Term
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Definition
| This is the value that people place on goods that they may wish to save for future generations, usually similar to existence value. |
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Term
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Definition
| A perception of the world that values the existence and diversity of all biological species, as opposed to a human-centered perspective (anthropocentrism). |
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Term
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Definition
| The variety of living organisms considered at all levels of organization, including the genetic, species, and higher taxonomic levels; and the variety of habitats and ecosystems, as well as the processes occuring therein. |
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Term
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Definition
| The use of a species to consume or otherwise control the population of a pest or invasive species. |
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Term
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Definition
| The ability to support and maintain balanced, integrated, functionality in the natural habitat of a given region. |
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Term
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Definition
| A large, regional ecological unit, usually defined by some dominant vegetative pattern, such as the coniferous forest biome. |
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Term
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Definition
| A concept of reserve design in which a large tract of natural area is set aside, containing an inviolate core area for ecosystem protection, a surrounding buffer zone in which nondestructive human activities are permitted, and a transition zone in which human activities of greater impact are permitted. Three goals of a biosphere reserve are conservation, training (education), and sustainable human development compatible with conservation. |
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Term
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Definition
| An area in a reserve surrounding the central core zone, in which nondestructive human activities such as ecotourism, traditional (low-intensity) agriculture, or extraction of renewable natural products, are permitted. |
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Term
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Definition
| Meat from animals, including edible invertebrates, that is harvested in the wild. |
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Term
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Definition
| The phenomenon where the extinction or change in abundance of a species causes changes in the abundance or extinction of many other species, which in turn causes such changes in still more species. |
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Term
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Definition
| A system of classification based on historical (chronological) sequences of divergence from a common ancestor. |
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Term
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Definition
| A diagram of cladistic relationships. An estimate or hypothesis of true genealogical relationships among species or other groupings. |
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Term
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Definition
| A concept in which particular genes from multiple loci have coevolved to collectively enhance fitness under a given set of environmental conditions. |
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Term
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Definition
| Originally referred to lands in medieval Europe that were owned by townships rather than by private individuals. Now used to include any exploitable resource that is not privately owned. Sometimes applied to so-called “open resources” that are neither privately owned nor regulated by a country or agency. |
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Term
| community based conservation |
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Definition
| A conservation approach that is rooted in local community development, is highly participatory, and seeks to make both conservation and development goals primary. |
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Term
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Definition
| In a reserve system context, a site selection process that includes many or most biodiversity features (e.g., species, ecological communities). |
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Term
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Definition
| An integrative approach to the protection and management of biodiversity that uses appropriate principles and experiences from basic biological fields such as genetics and ecology; from natural resource management fields such as fisheries and wildlife; from social sciences such as anthropology, sociology, philosophy, and economics; as well as other fields such as the creative arts and communications. |
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Term
| constructed market approach |
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Definition
| Also known as hypothetical market approach. Used in contingent valuation to express nonmarket values. For example, by determining a representative population’s willingness to pay to save a natural area or species a hypothetical market value can be assigned. |
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Term
| contingent valuation method |
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Definition
| Uses questionnaires and other inquiry methods to find nonmarket or indirect market values. Often expressed as a question, “How much would you be willing to pay to save the Artic National Wildlife Refuge?” See also willingness to pay. |
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Term
| conventional market approach |
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Definition
| Assigns a market value to environmental goods or services by comparing them to similar goods and services that have known market values. The general methods include opportunity costs, production-function, and substitute/alternative cost. |
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Term
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Definition
| A method of evaluating projects by assessing all project costs and benefits, usually in monetary units, over the lifetime of the project. See also discounting and net present value. |
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Term
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Definition
| According to U.S. Federal law, the ecosystems upon which endangered and threatened species depend. |
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Term
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Definition
| A precautionary approach that argues that certain environmental goods, services, and species are too important to be traded for gains in other forms of capital (e.g., financial, human-generated goods, human capital). Critical natural capital is said to be non-substitutable. An example might be the last remaining population of an endangered species. |
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Term
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Definition
| The aggregate desire for economic goods and services. The quantity of a good or service that consumers are willing to purchase at different prices. Demand involves the relationship between quantity and price. |
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Term
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Definition
| A randomly interbreeding (panmictic) local population. |
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Term
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Definition
| A significant, usually temporary, reduction in genetically effective population size, either from a population “crash” or a colonization event by a few founders. |
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Term
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Definition
| Chance populational events, such as sex ratios or the act of finding a mate that influence survival in small populations. |
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Term
| density-dependent factors |
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Definition
| Life history or population parameters that are a function of population density. |
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Term
| density independent factors |
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Definition
| Life history or population parameters that are independent of population density. |
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Term
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Definition
| The value we receive by using some part of the environment. For example, logging is a direct use value of a forest. |
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Term
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Definition
| The technique of placing a value on a project or resource at different times in the future. A high discount rate assumes that current values will decline rapidly in the future. |
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Term
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Definition
| The value of ecological entities irrespective of their usefulness to humans |
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Term
| ecological economic efficiency |
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Definition
| This is the ratio of man made capital services gained to natural capital services lost as a result. Clear-cutting a watershed results in poor efficiency. Sustainable logging would have higher efficiency. |
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Term
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Definition
| The impact a human community or nation has in terms of the amount of land or sea needed to produce the resources consumed. |
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Term
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Definition
| A characteristic of an ecosystem that is related to, or derived from, a measure of biotic or abiotic variable that can provide quantitative information on ecological structure and function. An indicator can contribute to a measure of integrity and sustainability. |
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Term
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Definition
| A living system exhibits integrity if, when subjected to disturbance, it sustains and organizes self-correcting ability to recover the state that is normal for that system. See also biological integrity. |
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Term
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Definition
| Habitat expansion or density increase of a species when one or more competing species are not present. |
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Term
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Definition
| The process of using ecological principles and experience to return a degraded ecological system to a more ecologically functional state. The goal of this process is to emulate the structure, function, diversity, and dynamics of the specified ecosystem. |
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Term
| ecologically functional population |
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Definition
| A population that is of sufficient size to fulfill its ecological roles. |
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Term
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Definition
| A relatively large area of land or water that contains a geographically distinct assemblage of natural communities. |
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Term
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Definition
| An approach to maintaining or restoring the composition, structure, and function of natural and modified ecosystems for the goal of long-term sustainability. It is based on a collaboratively developed vision of desired future conditions that integrates ecological, socioeconomic, and institutional perspectives, applied within a geographic framework defined primarily by natural ecological boundaries. |
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Term
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Definition
| The conditions and processes of natural ecosystems and species that provide some, usually utilitarian, human value. As examples, riparian swamps protect downstream property from flood damage or wild bees pollinate certain food crops. Ecosystem services are examples of indirect use values. |
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Term
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Definition
| Nature-based tourism; sometimes visiting new cultures is included in the definition. |
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Term
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Definition
| The negative influence of a habitat edge on interior conditions of a habitat, or on species that use interior habitat. Also, the effect of adjoining habitat types on populations in the edge ecotone, often resulting in more species in the edge than in either habitat alone. |
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Term
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Definition
| Achieving conservation objectives with the least possible cost. In a reserve system this often equates to minimizing the number of sites that need protection. |
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Term
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Definition
| An economic term that refers to the market’s ability to match resources with material ends. The apportionment of resources to the production of different goods and services. |
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Term
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Definition
| Species threatened with extinction by anthropogenic or natural changes in their environment. Requirements for declaring a species globally Endangered are described in the IUCN Red List. Countries often also have legal requirements for designating a species as endangered, such as in the U.S. Endangered Species Act. According to U.S. Federal law, an endangered species is a species in imminent danger of extinction throughout all or a significant portion of its range. |
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Term
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Definition
| Any localized process or pattern, but usually applied to a highly localized or restrictive geographic distribution of a species. |
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Term
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Definition
| Any localized process or pattern, but usually applied to a highly localized or restrictive geographic distribution of a species. |
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Term
| environmental impact assessment |
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Definition
| An analysis of the total beneficial and negative impacts of a project on the environment. |
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Term
| enviromnental modification |
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Definition
| Modification of the phenotype as a result of environmental influences on the genotype. |
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Term
| enviromnental uncertainty |
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Definition
| Unpredictable sources of density-independent mortality, such as an early snowstorm, that jeopardize the survival of a small population by pushing it below its minimum viable population size. |
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Term
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Definition
| Interactions among alleles at two or more loci that affect the state of a single trait, where the combined effects differ from the sum of the individual locus effects. |
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Term
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Definition
| A state reached when a population’s birth and immigration rates are equal to its mortality and emigration rates. Also applied to species changes in a community or to any other ecological process in which the rate of increase equals the rate of decrease, resulting in a steady state. |
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Term
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Definition
| Naturally, the slow aging process during which a lake, estuary, or bay evolves into a bog or marsh and eventually disappears. During the later stages of eutrophication the water body is choked by abundant plant life due to higher levels of nutritive compounds such as nitrogen and phosphorus. Human activities can accelerate the process, leading to rapid algal growth, and later hypoxia. |
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Term
| evolutionarily significant unit |
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Definition
| Partially genetically differentiated populations that represent a significant component of the evolutionary legacy of the species and that are considered to require management as separate units. |
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Term
| evolutionary-ecological land ethic |
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Definition
| A philosophical approach to conservation derived from the evolutionary and ecological perspective, first advanced by Aldo Leopold. Nature is seen not as a collection of independent parts, to be used as needed, but as an integrated system of interdependent processes and components, in which the disruption of some components may greatly affect others. This ethic is the philosophical foundation for modern conservation biology. |
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Term
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Definition
| The value, usually nonmarket, that is assigned by society to a place or species simply because its existence is considered important. For example, the Arctic Wildlife Refuge has a significant existence value for many people even though they may never visit it. |
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Term
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Definition
| The consumptive use of any natural resource |
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Term
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Definition
| Conservation efforts that take place in zoos, aquaria, greenhouses, or in other facilities. Usually involves storing and rearing individuals or genetic material for future reintroduction. Contrast with in situ conservation. |
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Term
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Definition
| A cost, usually in terms of environmental degradation, that results from an economic transaction but which is not included as a debit against economic |
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Term
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Definition
| A population size or density below which a population becomes at risk of immediate extinction. Used to describe the phenomenon when risk of extinction rises sharply with only a small change in population size or number of habitat patches occupied. |
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Term
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Definition
| Refers to a system whose output modifies input to the system. Prices play this role in market systems. |
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Term
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Definition
| The relative contribution of an individual’s genotype to the next generation in the context of the population’s gene pool. Relative reproductive success. |
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Term
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Definition
| All individuals in a population are identically homozygous for a locus (e.g., all A1A1). |
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Term
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Definition
| The principle that the founders of a new population carry only a random fraction of the genetic diversity found in the larger, parent population. Change in the genetic composition of a population due to founding or origin from a small number of individuals. |
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Term
| fundamental theorem of natural selection |
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Definition
| The basic theorem of population genetics, which states that the rate of evolutionary change in a population is proportional to the amount of genetic diversity (specifically, additive genetic variance) available in the population. |
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Term
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Definition
| The number of species found within a large region, which typically includes several habitats. |
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Term
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Definition
| The use of various remote sensing data sets to build overlaid sets of maps of various parameters (e.g., vegetation, soils, protected areas, species distributions) to identify spatial gaps in species protection and management programs. |
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Term
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Definition
| The uni- or bidirectional exchange of genes between populations due to migration of individuals and subsequent successful reproduction in the new population. |
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Term
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Definition
| The site on a chromosome occupied by a specific gene. See also locus. |
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Term
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Definition
| Group of interbreeding adults and progeny that collectively represent the bank of genetic material available in the population for future adaptation. |
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Term
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Definition
| Random changes in population allele frequency and levels of genetic diversity due to the finite number of individuals contributing genes to the next generation. |
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Term
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Definition
| The entire genetic constitution of an organism, or the genetic composition at a specific gene locus or set of loci. |
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Term
| geographic information system |
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Definition
| A computerized system of organizing and analyzing any spatial array of data and information. |
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Term
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Definition
| Change in a species’ trait over distance or among different distinct populations. Measurable character divergence among geographically distinct populations that are often, though not necessarily, the result of local selection. |
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Term
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Definition
| A form of spatial statistics originally created for analyzing irregular geological features. Now used in ecology to create probability maps from a limited set of location-specific data points. |
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Term
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Definition
| Refers to how organisms perceive spatial heterogeneity. The more time that an organism spends in any particular kind of environment, the more coarsely grained that environment is said to be. |
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Term
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Definition
| A gas, such as carbon dioxide or methane, which contributes to potential climate change. |
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Term
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Definition
| In conventional economics, any rate of increase in value that exceeds the rate of inflation. |
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Term
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Definition
| The decrease in the quality of an area due to human activities. |
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Term
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Definition
The disruption of extensive habitats into isolated and small patches; or the result of development in a large area where habitat is now fragmented into separate units; often applied to forested habitats that have been fragmented by agricultural development or logging. |
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Term
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Definition
| The conversion or transformation of a natural area into a wholly human occupied area of little or no use to wild species. |
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Term
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Definition
| The conversion or transformation of a natural area into a wholly human occupied area of little or no use to wild species. |
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Term
| Hardy-Weinberg Equilibrium |
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Definition
| The stability of gene frequencies expected in a sexual, diploid population when a number of assumptions are met, including random mating, a large population, and no migration, mutation or selection. |
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Term
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Definition
| Recognizes that goods may be described by an array of objectively measurable characteristics. For example, the price of a house may be made up of the prices ascribed to the number and size of rooms, the size of the garden, the quality of local services and the nature of the surrounding environment. See implicit market approach. |
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Term
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Definition
| The proportion of observed variation in phenotype that can be attributed to differences in genotype. |
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Term
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Definition
| Hybrid vigor or superior performance of hybrid genotypes, usually based on comparison to parental genotypes. Heterosis often results from the masking of deleterious alleles that occur in a homozygous state in high frequency in populations. Sometimes called hybrid vigor. |
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Term
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Definition
| A measure of the genetic diversity in a population, as measured by the number of heterozygous loci across individuals. |
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Term
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Definition
| The condition in which an individual has two different alleles at a given gene locus (e.g., Aa). Heterozygous individuals can produce two different gametes. |
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Term
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Definition
| A set of ordered steps for solving a problem whose general purpose is not to find a optimal solution, but an approximate solution where the time or resources to find a perfect solution are not practical. |
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Term
| heirarchical analysis of genetic diversity |
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Definition
| An approach to defining population genetic structure for a species in nature that defines components of total genetic diversity in a spatially hierarchical fashion. Genetic diversity can be apportioned in a hierarchical fashion (e.g., alleles within individuals, individuals within populations, populations within regions) to accomplish this goal. |
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Term
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Definition
| Possession by two or more species (or groups) of a similar or identical trait that has not been derived by both species (or groups) from their common ancestor. Homoplasy could result from convergence, parallel evolution, or character reversal. |
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Term
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Definition
| an individual having two copies of the same allele at a locus (AA or aa). The individual is genetically invariant because it can produce only one kind of gamete. |
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Term
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Definition
| A geographic location characterized by unusually high species richness, often of endemic species. |
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Term
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Definition
| Waters with dissolved oxygen concentrations of less than 2 ppm, the level generally accepted as the minimum required for most marine life to survive and reproduce |
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Term
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Definition
| An equation describing the total impact of humans on natural systems as a function of population size (P), level of affluence (A), and technological sophistication employed (T). |
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Term
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Definition
| Assigns market values to goods and activities that include the perceived value of the environment. For example, one might accept less wages to wait tables in a national park restaurant because the surrounding environment has perceived value. Two common methods are travel cost and hedonic pricing. |
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Term
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Definition
| The mating of individuals who are more closely related than by chance alone, such as relatives. Also the correlation of genes within individuals relative to that expected if individuals had mated at random. |
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Term
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Definition
| A reduction in fitness and vigor of individuals as a result of increased homozygosity through inbreeding in a normally outbreeding population. |
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Term
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Definition
| A species or higher taxonomic group used as a gauge for the condition of a particular habitat, community, or ecosystem. A characteristic, or surrogate species for a community or ecosystem |
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Term
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Definition
| The value, either market or nonmarket, that is provided by an environmental service. See also option value. |
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Term
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Definition
| Conservation efforts that take place in the wild. Contrast with ex situ conservation. |
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Term
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Definition
| the worth of an entity as judged by its utility or usefulness to humans. |
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Term
| ICDP (Integrated Conservation and Development Project) |
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Definition
| A term applied to large conservation projects that have the dual goal of improving people’s livelihoods while protecting biodiversity and ecosystem functions. |
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Term
| intermediate disturbance hypothesis |
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Definition
| An hypothesis (with good empirical support) that posits that maximum species richness in many systems occurs at an intermediate level (of intensity or frequency, or both) of natural disturbance. |
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Term
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Definition
| The worth of an entity independent from external circumstances or its value to humans; value judged on inherent qualities of an entity rather than value to other entities. |
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Term
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Definition
| A nonnative species that spreads rapidly and outcompetes, preys on and otherwise reduces or eliminates populations of native species. |
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Term
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Definition
| A conservation element that is nonsubstitutable, that is, an element that must be protected if conservation goals are to be met. |
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Term
| keystone mutualist species |
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Definition
| Keystone species that perform a mutualistic function, such as plant species that are broadly used as pollen sources. |
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Term
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Definition
| A species whose impacts on its community or ecosystem are large, and much larger than would be expected from its abundance. |
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Term
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Definition
| Areas that are presently island habitats, but were formerly connected to the mainland during periods of lower ocean levels. Land-bridge islands tend to lose species over time in a process called “relaxation.” |
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Term
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Definition
| The intervening area among a set of habitat fragments. Also the spatial array of habitats across a landscape. |
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Term
| landscape species approach |
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Definition
| A conservation approach developed by the Wildlife Conservation Society that uses wide-ranging focal species to design conservation efforts over a large landscape with both conservation and human uses. |
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Term
| linear programming ( LP ) |
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Definition
| A mathematical approach that finds the optimal solution, e.g., maximum net profit, by changing the values of the various constraints. For example, the optimal critical habitat for a species might be determined by varying the constraints of reserve size, migration corridors, food abundance, and density of predators to determine which combination of real constraints provides the critical habitat with the highest probability of survival for the species in question. |
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Term
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Definition
| Physical location occupied by a gene on a chromosome. Used interchangeably with gene. See gene locus. |
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Term
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Definition
| A marine site in which some or all human uses are prohibited. |
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Term
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Definition
| The extinction of large numbers of taxa during a relatively brief geologic time frame, such as the extinction of dinosaurs at the end of the Cretaceous Period. |
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Term
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Definition
| Form of sexual selection where one sex (usually females) determines whether mating occurs or not, often on the basis of phenotypic or behavioral characteristics of the opposite sex. |
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Term
| maximum sustained yield (MSY) |
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Definition
| The largest harvest level of a renewable resource that can be sustained over a period of many generations. Harvest of a natural population at the population size representing the maximum rate of recruitment into the population, based on a logistic growth curve. |
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Term
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Definition
| Refers to medium-sized predators, such as raccoons and foxes, that often increase in abundance when larger predators are eliminated. |
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Term
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Definition
| A network of semi-isolated populations with some level of regular or intermittent migration and gene flow among them, in which individual populations may go extinct but can then be recolonized from other populations. |
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Term
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Definition
| The smallest area necessary for a reserve to have a complete, natural disturbance regime in which discrete habitat patches may be colonized from other patches within the reserve. |
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Term
| minimum viable population (MVP) |
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Definition
| The smallest isolated population that has a specified statistical chance of remaining extant for a specified period of time in the face of foreseeable demographic, genetic, and environmental stochasticities, plus natural catastrophes. |
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Term
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Definition
| Presence of only one allele at a locus. Lack of genetic diversity. Contrast wth polymorphic. |
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Term
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Definition
| Species that are distinguished on the basis of appearance; often used in field studies when taxonomies and keys are incomplete; a morphospecies is not a formal taxonomic entity. |
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Term
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Definition
| Similar to linear programming but more than one criterion is optimized. For example, one might want to jointly optimize the combination of tourist access and habitat quality for a species that has value for ecotourism. |
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Term
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Definition
| Those traits whose phenotype is affected by many genes. Also called polygenic traits. Often form continuous distributions (e.g., length, weight, condition factor). |
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Term
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Definition
| Refers to the simultaneous and compatible use of public land and water resources by different interest groups. For example, U.S. public law requires that national forests be open to recreational use, timber extraction, mining or other concessions, and biodiversity protection. In reality, the activities of the various interest groups generally conflict, and are often incompatible with biodiversity protection. |
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Term
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Definition
| A spontaneous change in the genotype of an organism at the genetic, chromosomal, or genomic level, usually caused by errors in replication. “Mutation” usually refers to alterations to new allelic forms, and represents new material for evolutionary change, although most mutations are either mildly or strongly deleterious. |
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Term
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Definition
| The decline in reproductive rate and downward spiral towards extinction due to chance fixation of new mildly deleterious mutations in small populations. |
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Term
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Definition
| An interspecific relationship in which both organisms benefit; frequently a relationship of complete dependence. Examples include flower pollination and parasite cleaning. |
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Term
|
Definition
| A major environmental cause of mortality, such as a volcanic eruption, that can affect the probability of survival for both large and small populations. |
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Term
|
Definition
| A process by which differential reproductive success of individuals in a population results from differences in one or more hereditary characteristics. Natural selection is a function of genetically based variation in a trait, fitness differences (differential reproductive success) among individuals possessing different forms of that trait, and inheritance of that trait by offspring. |
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Term
|
Definition
| A pattern of species biogeographic distribution in which larger habitats contain the same subset of species in smaller habitats, plus new species found only in the larger habitat. Common species are found in all habitat sizes, but some species are found only in progressively larger habitats. |
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Term
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Definition
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Term
|
Definition
| Net production of plant biomass, and the basis of all food webs. |
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Term
| neutral genetic variation |
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Definition
| Genetic variation (alleles or genotypes) that is not or appears not to be subject to natural selection. |
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Term
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Definition
| A condition in which the rate of increase does not equal the rate of decrease. In nonequilibrial population growth, environmental stochasticity disrupts the equilibrium. |
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Term
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Definition
| Contamination of water resources by excessive inputs of nutrients. In surface waters, excess algal production is a major concern. |
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Term
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Definition
| The value forgone when not taking a particular option. When choosing one option precludes other options, the value assigned to those other options is the opportunity cost. |
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Term
| opportunity cost approach |
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Definition
| Uses conventional markets to assign forgone value when one action is taken over another. For example, protecting trees in a reserve may have many benefits but it also has an opportunity cost in the form of forgone timber sales. |
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Term
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Definition
| An economic term that refers to assigning a value to some resource whose consumption is deferred to the future; the value placed on environmental assets by people who want the use of it in the future. Yet to be discovered medicinal plants means that rainforests have an option value. |
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Term
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Definition
| Reduction in reproductive fitness due to crossing of individuals from two genetically differentiated populations. |
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Term
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Definition
| The condition in which a heterozygote at a given locus has higher fitness than either homozygote. Also called heterozygote superiority. |
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Term
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Definition
| Exhibiting random breeding among individuals of a population. |
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Term
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Definition
| An established pattern of thinking. Often applied to a dominant ecological or evolutionary viewpoint; e.g., during earlier decades, the dominant paradigm in ecology held that communities were shaped by equilibrial processes. |
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Term
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Definition
| A conceptual approach to ecosystem and habitat analysis that emphasizes dynamics of heterogeneity within a system. Diverse patches of habitat created by natural disturbance regimes are seen as critical to maintenance of diversity. |
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Term
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Definition
| Use of pedigrees in conservation planning, particularly for captive propagation, to avoid inbreeding and maximize genetic diversity. |
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Term
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Definition
| The physical expression (outward appearance) of a trait of an organism, which may be due to genetics, environment, or an interaction of the two. |
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Term
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Definition
| Individuals returning to the same area to breed. |
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Term
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Definition
| the evolutionary relatedness of the species present in an area. |
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Term
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Definition
| The evolutionary or cladistic relationships among species or higher taxa; the relatedness through descent of any taxon; e.g., the phylogeny of birds leads back to certain lines of dinosaurs. |
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Term
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Definition
| Evolutionary relationships among species populations based on geographic relationships and historical gene flow patterns. |
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Term
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Definition
| Study of the geographical distribution of genealogical lineages, especially within species. |
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Term
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Definition
| The condition of genetically based, environmentally induced variation in characteristics of an organism. |
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Term
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Definition
| One gene affects two or more traits. |
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Term
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Definition
| A school of thought which holds that species concepts should vary with the taxon under consideration. Many different species definitions would be employed. |
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Term
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Definition
| The number of species found at a single point in space. |
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Term
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Definition
| More than one allele at a genetic locus. Contrast with monomorphic. |
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Term
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Definition
| Possessing more than two complete sets of chromosomes. |
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Term
| Population Viability Analysis (PVA) |
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Definition
| A quantitative analysis of the many environmental and demographic factors that affect survival of a population, usually applied to small populations at risk of extinction |
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Term
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Definition
| The principle that when information about potential risks is incomplete, decisions about the future policies should be based on a preference for avoiding unnecessary environmental or health risks. |
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Term
| production function approach |
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Definition
| Uses conventional markets to assign a value to some change in environmental conditions that affect productivity. For example, the value of reforesting a watershed could be expressed in the market value from increases in crop production that results from a more abundant water supply. |
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Term
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Definition
| A site where human uses are restricted or prohibited and where conservation of biodiversity is a primary goa |
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Term
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Definition
| The study of phenotypic traits that are influenced by multiple genetic and environmental factors (polygenic traits). |
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Term
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Definition
| A revegetation or land management goal that includes a lower diversity of species and may include substitutions by introduced species. |
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Term
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Definition
| The act of entirely reconstructing a site denuded of its terrestrial and/or aquatic systems. This commonly occurs on surface mined lands and in brownfields (severely damaged urban and industrial lands). Also termed creation, but creation implies transforming a site to a completely different ecosystem than had previously existed on the site. |
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Term
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Definition
| Creation of an alternative ecosystem following a disturbance, different from the original and having utilitarian rather than conservation values. To repair damaged or blocked ecosystem functions, with the primary goal of raising ecosystem productivity for the benefit of local people. |
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Term
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Definition
| An attempt to establish a species in an area which was once part of its historical range, but from which it has been extirpated or become extinct. |
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Term
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Definition
| The loss of species on land-bridge islands following separation from the mainland or the loss of species during any process of habitat fragmentation and isolation. |
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Term
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Definition
| Removal of toxicants from a contaminated environment using chemical, physical, or biological means. |
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Term
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Definition
| Any technique for analyzing landscape patterns and trends using low altitude aerial photography or satellite imagery. Any environmental measurement that is done at a distance. |
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Term
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Definition
| In a reserve system, the quality of a set of sites that together include all or most biodiversity elements (e.g., species or ecological communities). |
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Term
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Definition
| The recolonization of a habitat when a subpopulation of a metapopulation has gone locally extinct. |
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Term
| resource conservation ethic |
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Definition
| A philosophical approach to conservation derived from the views of forester Gifford Pinchot, based on the utilitarian philosophy of John Stuart Mill. Nature is seen as a collection of natural resources, to be used for “the greatest good of the greatest number for the longest time.” |
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Term
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Definition
| The process of identifying, evaluating and managing the risks that may arise from a given action or activity; e.g., the risk assessment of releasing a species as part of a biological control or a species reintroduction program. |
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Term
| Romantic Transcendental Conservation Ethic |
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Definition
| A philosophical approach to conservation derived from the writings of Emerson, Thoreau, and Muir, in which nature is seen in a quasi-religious sense, and as having uses other than human economic gain. This ethic strives to preserve nature in a wild and pristine state. |
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Term
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Definition
| The magnitude of a region or process. Refers to both spatial size—for example, a relatively small-scale patch or a relatively large-scale landscape; and temporal rate—for example, relatively rapid ecological succession or relatively slow evolutionary speciation. |
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Term
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Definition
| When the loss of population change in a species affects other species, often through their trophic interactions. |
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Term
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Definition
| Differential survival (viability selection) and reproduction (fertility selection) by different genotypes in the population or the differential success of genotypes passing gametes to other generations (sexual selection). See also natural selection. |
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Term
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Definition
| Capable of feeling or perception. Refers to a state of self-awareness among organisms, usually applied only to vertebrates. |
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Term
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Definition
| A common method used in systematic conservation planning where a search for potential sites to include in a reserve system can include both optimal (good) and nonoptimal (bad) choices initially to achieve a better final result. |
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Term
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Definition
| Traits whose phenotype is largely controlled by a single gene. Usually falls into discrete or qualitative categories such as normal versus albino coat coloration. |
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Term
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Definition
| A habitat in which local mortality exceeds local reproductive success for a given species. |
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Term
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Definition
| A population in a low-quality habitat in which the birth rate is generally lower than the death rate and population density is maintained by immigrants from source populations. |
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Term
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Definition
| An acronym for “single large or several small,” reflecting a debate that raged for several years asking whether, all else being equal, it was better to have one large reserve or several small reserves of the same total size. |
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Term
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Definition
| Spatial linkage of population dynamics such that high-quality habitats (sources) provide excess individuals that maintain population density, through migration, in low-quality habitats (sinks). |
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Term
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Definition
| A habitat in which local reproductive success exceeds local mortality for a given species |
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Term
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Definition
| A population in a high-quality habitat in which the birth rate greatly exceeds the death rate and the excess individuals leave as emigrants. |
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Term
| spatially-explicit population model |
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Definition
| A population model, especially a simulation model, that takes space, differences in habitat quality, and inter-habitat movement into consideration. |
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Term
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Definition
| Usually synonymous with “species richness,” but may also include the proportional distribution of species. |
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Term
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Definition
| The number of species in a region, site, or sample. See also a-, b- and g-richness. |
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Term
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Definition
| Management of natural resources that conserves them for future generations. Usually used to distinguish from short-term, utilitarian management objectives. |
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Term
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Definition
| An economy that has a constant stock of people and artifacts maintained at some desired sufficient levels by low rates of maintenance (or throughput). A steady state economy does not assume that continued economic growth, as measured by indicators like Gross Domestic Product (GDP), is prerequisite for sustainable development. |
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Term
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Definition
| Random; specifically refers to any random process, such as mortality due to weather extremes. |
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Term
| substitute/alternative cost approach |
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Definition
| Estimates the market value of an environmental good by comparing it to a logical substitute that has an established market value. For example, in this approach the value of hunting a deer would be approximated by the value of an equivalent amount of purchased meat. |
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Term
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Definition
| The natural, sequential change of species composition of a community in a given area. |
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Term
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Definition
| Addition of individuals to an existing population of conspecifics. Sometimes called reinforcement. |
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Term
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Definition
| he aggregate amount of goods or services available to satisfy economic needs or wants. The quantity of a good or service which producers are willing to sell at different prices. Supply involves the relationship between quantity and price. |
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Term
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Definition
| One or more species selected as focal species for conservation planning with the intention that other species will also be conserved by the same efforts. Surrogate species are often ones with large-ranges, or sensitive to disturbance, or which have similar ecology to target species. |
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Term
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Definition
| In general, the attempts to meet economic objectives in ways that do not degrade the underlying environmental support system. Note that there is considerable debate over the meaning of this term. In Chapter 18, we define it as “human activities conducted in a manner that respects the intrinsic value of the natural world, the role of the natural world in human well-being, and the need for humans to live on the income from nature’s capital rather than the capital itself.” |
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Term
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Definition
| An interaction that has more than additive effects; for example, when the joint toxicity of two compounds is greater than their combined, independent toxicities. |
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Term
| systematic conservation planning |
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Definition
| The deliberate planning process of selecting sites to include in a reserve system using explicit criteria. |
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Term
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Definition
| Used internationally to refer to any species listed as Critically Endangered, Endangered, or Vulnerable according to the IUCN Red List of Threatened Species definitions. According to U.S. Federal law, a threatened species is a species that is likely to become endangered in the foreseeable future. |
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Term
| total economic value (TEV) |
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Definition
| The sum of all use and nonuse values including both market and nonmarket. |
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Term
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Definition
| An idea (set forth primarily by Garrett Hardin) that unregulated use of a common, public resource for private, personal gain will result in overexploitation and destruction of the resource. |
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Term
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Definition
| Management technique often used in mitigation for endangered species protection whereby an individual, population, or species is removed from its habitat to be established in another area of similar or identical habitat. |
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Term
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Definition
| Commonly used to evaluate recreational or conservation areas. Estimates how much people are willing to pay in travel and opportunity costs to visit a particular site, or to see a particular phenomenon, e.g., a wild Bald Eagle. It is part of the implicit market approach. |
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Term
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Definition
| All values except existence value. |
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Term
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Definition
| A philosophical term applied to any activity that produces a product useful to humans, typically in some economic sense. Also used to describe a system of values which is measured by its contribution to human well-being, usually in terms of health and economic standard of living. |
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Term
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Definition
| The difficult to measure sense of well-being. Economists generally use monetary terms as surrogate measures of utility. Also the “want-satisfying” power of goods; personal satisfaction received through an economic gain. |
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Term
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Definition
| the process of a continuously distributed biota becoming separated by an intervening geographic event (such as mountain uplift or river flow), or extinction of intervening populations, resulting in subsequent independent histories of the fragmented biotas, and possible speciation events. |
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Term
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Definition
| A population size or density below which a population becomes vulnerable to extinction. Used particularly to describe the phenomenon when risk of extinction rises sharply with only a small change in population size or number of habitat patches occupied. |
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Term
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Definition
| The land area that drains into a stream; the watershed for a major river may encompass a number of smaller watersheds that ultimately combine at a common point. |
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Term
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Definition
| Used in contingent valuation to estimate the value of a nonmarket good. WTP would generally be determined through questionnaires distributed to a representative population asking something like, “How much would you be willing to pay to protect a certain reserve or species?” |
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Term
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Definition
| An important component of reserve design that controls human activities within and adjacent to conservation reserves, so that reserve function may be protected while some human activities, including those supplying some economic benefit, may take place. |
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