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Michigan State UniversityWildlife Toxicology Laboratory

Glossary of Terms

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  • addled eggs: eggs that will not hatch despite being incubated
  • amphibian: any of a class (amphibian) of cold-blooded vertebrates (such as frogs, toads, or salamanders) intermediate in many characteristics between fishes and reptiles and having gilled aquatic larvae and air-breathing adults
  • aquatic: living or growing in water
  • aquatic emergent insects: insects with an aquatic larvae stage that emerge from the river during the adult stage, becoming an important food resource for wetland wildlife and providing a link between the aquatic and terrestrial ecosystems
  • aquatic toxicology: the study of the effects of artificially produced or introduced chemicals, natural materials, and activities on aquatic organisms at various levels of organization, from subcellular through individual organisms to communities and ecosystems
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  • basin (river): an enclosed or partly enclosed water area
  • benthic: of, relating to, or occurring at the bottom of a body of water
  • benthic invertebrates: aquatic animals without backbones that dwell on or in the bottom sediments of fresh or salt water (Note: benthos refers to the bottom, and these animals are also called zoobenthos; many of these inhabitants are immature stages of insects, such as mayflies, stoneflies, caddis flies, and midges.)
  • body burden: the amount of a harmful substance permanently stored in a living organism, usually expressed in mass units, such as grams and milligrams (Note: the substance may be radioactive or chemically toxic. Many harmful substances can be eliminated naturally by the body, but some are removed very slowly or not at all. Water soluble molecules are usually easy to remove. Non-polar molecules (that is, molecules that have no separation of charge, so no positive or negative poles are formed), however, are lipophilic and tend to accumulate in fat tissue, which is also non-polar, and therefore difficult for the body to eliminate.) See also non-polar molecule.
  • bolus samples: small masses of chewed food
  • breeding cycle: the time period for reproduction—beginning at nest building and continuing through egg laying and raising young to the point of independence
  • breeding season: the most suitable season, usually with favorable conditions and abundant food and water, for breeding among wild animals and birds (Note: different species of wild animal and birds have different breeding seasons according to their particular requirements and food availability, etc.)
  • burrow excavating: a process during which an active nest of a burrowing bird, such as the belted kingfisher, is accessed by means of careful digging in order to gather reproductive data, such as clutch size
  • burrow: a hole or excavation in the ground made by an animal for shelter and habitation
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  • cavity: a hole or opening in a tree trunk or limb
  • cavity nesting bird: birds that nest in cavities in dead or decadent trees or in a nest box
  • clutch: the total number of eggs laid by a female bird in one nest attempt
  • confluence: the flowing together of two or more rivers; also, the combined river formed by the conjunction of two or more rivers
  • contaminants: those compounds that potentially make a habitat unfit for use by the introduction of unwholesome or undesirable elements
  • contaminant concentration: the amount of a contaminant within a given system, often measured in parts per million or parts per billion
  • contaminant concentration analysis: the process by which a specific contaminant concentration is determined via chemical analysis
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  • delineating territories: the process of distinguishing the home ranges of single or breeding pairs of wildlife species
  • dietary exposure: the line of evidence analyzing the introduction of contaminants to an individual via dietary items
  • dioxins: any of several persistent toxic heterocyclic hydrocarbons that occur especially as by-products of various industrial processes (such as pesticide manufacturing and paper making) and waste incineration (Note: current scientific literature uses the term dioxins to denote the chlorinated derivatives of dibenzo-p-dioxin, more precisely the polychlorinated dibenzodioxins [PCDDs].)
  • downstream: in the direction of or nearer to the mouth of a stream or river
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  • ecological risk assessment: a process for systematically evaluating how likely it is that adverse ecological effects may occur as a result of exposure to one or more stressors (Note: the goal of ecological risk assessment is to help understand the relationships between stressors and ecological effects to inform risk management decisions. These can be applied prospectively—to predict the likelihood of future adverse effects—and retrospectively—to evaluate the likelihood that observed effects are caused by past exposure to stressors. The ecological risk assessment process can be adapted to predict beneficial changes or risks from natural events. Ecological risk assessments help risk managers determine which course of action to take for ecosystems that have been, or could be, exposed to stressors. Ecological risk assessments are used for many types of management actions, including the regulation of hazardous waste sites, industrial chemicals, and pesticides.)
  • egested: the act or process of discharging undigested or waste material from a cell or organism, defecation
  • environmentalist: one concerned about environmental quality, especially of the human environment with respect to the control of pollution
  • enzymes: biomolecules that increase the rate of various chemical reactions
  • enzyme induction: the increase in an enzyme’s production rate due to the presence of a gene expression altering compound
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  • fledge: the act of leaving the nest or nest cavity after reaching a certain stage of maturity, often associated with the completed development of feathers
  • fledgling: a young bird that has just fledged, i.e., developed or grown feathers
  • fledge success: the success of nestlings to develop normally and fledge from the nest
  • fledgling survival: the survival of young birds to fledglings after they have hatched
  • floodplain: level land that may be submerged by floodwaters or a plain built up by stream deposition
  • food chain: an arrangement of the organisms of an ecological community according to the order of predation in which each uses the next lower member as a food source; also called food web
  • forage (n.): food for animals, especially when taken by browsing or grazing
  • forage fish: any fish eaten by large predatory fish, seabirds, or marine mammals (Note: forage fish are usually abundant and often swim in large schools. Forage fish are an important link in the aquatic food web because they transfer energy between primary and secondary producers, such as plankton, to top predators, such as seabirds and larger fish.)
  • furans: cyclic flammable liquid compounds that are obtained from the wood oils of pines or made synthetically and are similar in toxicity to dioxins; used especially in organic synthesis
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  • Habitat Suitability Index: a tool for predicting the quality or suitability of habitat for a given species based on known affinities with habitat characteristics, such as depth and substrate type (Note: this information is combined with maps of these same habitat characteristics to produce maps of expected distributions of species and life stages. A suitability index provides a probability that the habitat is suitable for the species and, hence, a probability that the species will exist where that habitat occurs. If the value of the index is high in a particular location, then the chances that the species occurs there are higher than if the value of the index is low.)
  • hatch: to emerge (an organism) from an egg, pupa, or chrysalis
  • hatch success: the productive growth of eggs to a hatched bird; i.e., eggs that hatch
  • histology: a branch of anatomy that studies the minute structure of animal and plant tissues as discernible with the microscope; tissue structure or organization
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  • ice out: the time when lake or river ice melts (Note: specific definitions for ice out vary from body of water to body of water and person to person but generally fall within one of three meanings: 1. when the body of water is completely free of ice; 2. the moment when navigation is possible from point a to point b; 3. when 90 percent of a body of water is ice free.)
  • incubation: the process by which birds provide a constant temperature to their eggs in order to allow the appropriate conditions for the embryo to develop
  • indigestible: impossible to digest or not easily digested
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  • leg band: (also known as bird ringing and bird banding) an aid to studying wild birds by attaching a small, individually numbered metal or plastic ring to their legs (sometimes wings), so that various aspects of the bird’s life can be studied by finding the same bird later (Note: the information studied includes migration, longevity, mortality, population, feeding behavior, and other aspects of behavior.)
  • line of evidence: an approach for analyzing the exposure of wildlife to compounds, such as the analysis of dietary items to predict the exposure of chemical compounds therein, on individuals
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  • migratory species: species, particularly birds, that undertake regular seasonal journeys that include movements of varied distances made in response to changes in food availability, habitat, or weather (Note: migration is marked by its annual seasonality. In contrast, birds that are nonmigratory are known as resident birds.)
  • mist nets: nets used by ornithologists to capture wild birds for banding or other research projects (Note: the mesh net is typically made of nylon and resembles an oversized volleyball net. The grid size of the mesh netting varies according to the size of the avian species targeted for capture. Net dimensions are approximately 1–1.5 m high by 6–12 m long. When properly deployed, the nets are virtually invisible. If used by trained personnel, mist netting is an efficient method of capturing wild birds in flight while posing minimal risk of incidental injury to entrapped birds. The mist net consists of two poles with the net strung between them. A bird caught in a mist net will struggle, entangling itself further, so the net must be checked often and the bird removed promptly. Disentangling a bird from a mist net can be difficult and must be done carefully by trained personnel; if a bird is heavily tangled the mist net should be cut to avoid injuring the bird.)
  • morphology: a branch of biology that deals with the form and structure of animals and plants
  • multiple lines of evidence: the use of numerous approaches to analyze the exposure of wildlife to compounds, such as the analysis of dietary items to predict individual exposure to particular substances, the analysis of a receptor species’ tissues, and the analysis of reproductive endpoints
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  • necropsy: an autopsy performed on an animal
  • nest success: nests that produce one or more fledglings
  • nesting box: a human-made box provided for animals to nest in (Note: nest boxes are most frequently utilized for wild and domesticated birds, but certain species of mammals may also use them. Sometimes called a birdhouse, a box is typically made of wood in which cavity nesting birds can nest.)
  • nesting colonies: an area in which a breeding pair nests during their breeding season in close proximity to the nests of other breeding pairs of the same species in a communal effort to protect their nests from predator activity
  • nesting platform: an artificial or natural arrangement of materials on or in which eggs and nestlings are tended to by adult avian species
  • nestling: a young bird that has yet to mature to fledging age
  • non-polar molecule: a compound that occurs when there is an equal sharing of electrons between two different atoms (Note: examples of household non-polar compounds include fats, oil, and petrol/gasoline. Like dissolves like; therefore, most non-polar molecules are water insoluble at room temperature. However many non-polar organic solvents, such as turpentine, are able to dissolve non-polar substances.
  • nontarget occupancy: occupancy of a nest by a species not being studied
  • nonviable eggs: eggs that do not hatch
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  • obligate cavity nesters: dependent on natural cavities or, more importantly, nest boxes
  • ornithologist: one who studies the branch of zoology focused on birds
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  • passerine: a bird of the order passeriformes, which includes more than half of all bird species (Note: sometimes known as perching birds or, less accurately, as songbirds, the passerines form one of the most diverse terrestrial vertebrate orders, with approximately 5,093 species.)
  • pellet: a wad of indigestible material (as of bones and fur) regurgitated by a bird of prey
  • pileated (woodpecker): having a crest covering the pileum, that is, the top of the head of a bird from the bill to the nape
  • plasma: the fluid part of blood, lymph, or milk as distinguished from suspended material, especially blood plasma
  • prey: an animal taken by a predator as food
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  • radio telemetry: a technology that allows the remote measurement and reporting of information of interest to the system designer or operator (Note: radio telemetry typically refers to wireless communications that use a radio system to implement the data link.)
  • radio transmitter: a device used in radio telemetry that emits a radio signal used to locate the individual carrying the transmitter
  • raptor: a bird of prey
  • receptor species: a species selected for study based on suitable representation of similar species and position in the food chain
  • reconstructed diet: the process by which prey remains and individual tissues of prey items are analyzed to predict dietary exposure
  • reference area: the region of the floodplain upstream of the input of the compound being analyzed in the study area; utilized as the source for comparison data against the study area’s findings
  • regurgitate: the flow of stomach contents to the mouth by a bird feeding its young; also, to expel indigestible material
  • reproductive variable analysis: the line of evidence quantifying hatch success, fledge success, nest success, and population abundance
  • riparian: relating to or living or located on the bank of a natural watercourse (as a river) or sometimes a lake or a tidewater
  • rookery: the nests or breeding place of a colony of rooks; also, a breeding ground or haunt especially of gregarious birds or mammals; also, a colony of such birds or mammals
  • roost (n): a support on which birds rest; also a group of birds resting together
  • roost (v): to settle down for rest or sleep; to perch
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  • sediment: the matter that settles to the bottom of a liquid; material deposited by water, wind, or glaciers, sometimes in a lake or river
  • site-specific: data that is directly derived from a particular area
  • songbirds: (also known as oscine) a bird belonging to the suborder passeri of passeriformes (approximately 4000 species), in which the vocal organ is developed in such a way as to produce various sound notes, commonly known as bird song (Note: this bird song is essentially territorial in that it communicates the identity and whereabouts of an individual to other birds and also signals sexual intentions. It is not to be confused with bird calls, which are used for alarms and contact, and are especially important in birds that feed or migrate in flocks.)
  • species: related organisms or populations having common attributes and potentially capable of interbreeding
  • species abundance: the measure of the abundance of individuals of a given species in a community (Note: generally species abundance is examined relative to the abundance of other species represented in the community.)
  • sustainability: a characteristic of a process or state that can be maintained at a certain level indefinitely
  • synchronous hatching: hatching that occurs at the same time or nearly the same time within a nest (usually within one calendar day)
  • synchronous nesting: nesting by a local population in which breeding pairs initiate egg laying within a relatively short period of time (a few days to a few weeks)
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  • taxonomic groups: the classification of plants and animals according to their presumed natural relationships
  • taxonomy: scientific naming of organisms and their classification with reference to their precise position in the animal or plant kingdom
  • telemetry: a technology that allows the remote measurement and reporting of information of interest to the system designer or operator
  • terrestrial invertebrates: organisms without a backbone, such as insects and spiders, with life stages isolated to land rather than bodies of water
  • tissue concentration: the amount of a given compound or compounds within cells or organs, such as in plasma, fat, or muscle tissue
  • transition areas: the region where two different habitat types intersect, typically sharing characteristics of both habitats; also referred to as edge habitat
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  • uterine horns: the points where the uterus and the uterine tubes meet
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  • watershed: a region or area bounded peripherally by a divide and draining ultimately to a particular watercourse or body of water
  • wildlife toxicology: the study of the effects of artificially produced or introduced chemicals, natural materials, and activities on terrestrial organisms at various levels of organization, from subcellular through individual organisms to communities and ecosystems
  • Wildlife Toxicology Laboratory: The Wildlife Toxicology Laboratory (WTL) is part of the Michigan State University Department of Animal Science. MSU-WTL researchers conduct long-term studies of the accumulation, metabolism, and effects of toxic substances and therapeutic agents on aquatic and terrestrial organisms under controlled laboratory conditions as well as field-based aquatic and terrestrial ecosystems conditions by means of comprehensive sampling in support of ecological risk assessments.
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