A habitat found on limestone bedrock with very shallow or no soil usually subject to harsh weather conditions. Alvars contain a distinct set of plant and animal specialists. North American alvars are found in the Great Lakes basin and are considered globally imperilled by the Nature Conservancy...
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lake erie ecoregion
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lake trout
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abiotic
The non-living components of the environment, for example, air, water and rocks.......................
Simple, free floating one-celled or many-celled micro-organisms capable of carrying on photosynthesis in aquatic ecosystems..
anadromous
anadromous
Fish that spend most of their life in open waters, but then migrate to tributaries to spawn, e.g. Atlantic Salmon.
anoxia
The absence of oxygen necessary for sustaining most life. In aquatic ecosystems, this refers to the absence of dissolved oxygen in water..e
anoxia
area of concern
An area recognized by the International Joint Commission where one or more of 14 beneficial uses are impaired or where objectives of the Great Lakes Water Quality Agreement or local environmental standards are not being achieved.
area of concern
atmospheric deposition
Pollution from the atmosphere falling from air or water. It is associated with dry deposition in the form of dust, wet deposition in the form of rain and snow, or occurs as a result of vapor exchanges..........
atmospheric deposition
basin
A geographic area that includes a lake and its watershed
basin
bioaccumulation
A general term describing a process by which chemical substances are ingested and retained by organisms from the environment directly or through consumption of food containing the chemical...............................
bioaccumulation
biodiversity
The variety and variability among living organisms and the ecological complexes in which they occur. For biological diversity, these items are organized at many levels ranging from complete ecosystems down to the chemical structures that are the molecular basis for heredity. Thus, the term encompasses different ecosystems, species, genes, and their relative abundance..
diversity
buttonClick
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diversity
biodiversity
biodiversity convention
biodiversity convention
The Biodiversity Convention was proposed at the United Nation Conference on Environment and Development held in Rio de Janeiro, Brazil in 1992. The three objectives of the convention are the importance of biodiversity, conservation, developing methods of sustainable resource use; and sharing the benefits of genetic resources. Canada has signed the covention and is committed to developing strategies suppoting the objectives.
biomagnification
A cumulative increase in the concentration of a persistent substance in successively higher trophic levels of the food chain (i.e., from algae to zooplankton to fish to birds).
omagnification has been demonstrated in studies that measured PCBs and DDT in different animals in the food web. Plankton, crustaceans (such as freshwater shrimp) and amphipods (such as the freshwater scud) obtain nutrients and contaminants from suspended particles and represent one of the lowest tiers of the Great Lakes food web; they also have the lowest contaminant concentrations. These small organisms may then be consumed by fish, such as sculpin, which live near the bottom of the lake, or smelt. Eventually these fish are eaten by larger predators such as Lake Trout or gulls. At each step of the food web, contaminant levels are multiplied. Gulls tend to accumulate higher concentrations of contaminants than Lake Trout because gulls, unlike trout, are warm-blooded animals and require more food to maintain their body temperature. The more food eaten, the more contaminants a gull will absorb.
biomagnification
biomass
Total dry weight of all living organisms in a given area.
biomass
biomonitoring
The use of organisms to test the acute toxicity of substances in effluent discharges as well as the chronic toxicity of low-level pollutants in the ambient aquatic environment..
biomonitoring
bioregion
An area of human habitation bounded by natural features such as shorelines and landforms.
bioregion
Biochemical oxygen demand (BOD) is the amount of dissolved oxygen required for the bacterial decomposition of organic waste in water.
buffer strip
A strip of vegetation that is left in its natural state or managed to reduce the impact of a treatment or action from one area to another...
buffer strip
carcinogen
A substance (or radiation energy) which induces cancer in living organisms........................................................
carcinogen
Census Metropolitan Area
The general concept of a Census Metropolitan Area (CMA) is one of a very large urban area, together with adjacent urban and rural areas that have a high degree of economic and social integration with that urban area. A CMA is delineated around an urbanized core having a population of at least 100 000 (Statistics Canada 1994b)...
Census Metropolitan Area[
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Canadian Environmental Protection Act (CEPA) is an Act respecting the protection of the environment and human life and health. When CEPA was created in 1988,
the government brought together, in a comprehensive piece of legislation, environmental provisions of several other statues administered by Environment Canada. Those provisions include those dealing with toxic substances, nutrients, ocean dumping, environmental
research, guidelines and codes of practice as well as agreements with provinces and territories.......
community
Populations of different species inhabiting the same area or habitat, bound together by their biotic relationships.
community
congener
A congener is a chemical that belongs to a family of chemicals. For example PCB congeners have different numbers of chlorine atoms at different locations on their ring structure...ent locations on their ring structure..rs have different numbers of chlorine atoms at different locations on their ring structure.................................
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buttonClick
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congener
consumptive use
Permanent removal of water from a water body. Consumptive use may be due to evaporation, incorporation of water into a manufactured product, or drinking.
consumptive use
contaminant
Any substance that adversely affects the health or well-being of any living organism.
contaminant
conversion table
Metric to Imperial Values
1 metre = 3.28 feet
1 kilometre = 0.621 miles
1 kilogram = 2.2 pounds
1 square kilometre = 0.386 square miles
1 cubic kilometre = 0.24 cubic miles
1 litre = 0.264 U.S. gallons
1 cubic metre/second = 35.31 cubic feet/second
1 tonne = 1.1 short tons
conversion table
Dichloro-diphenyl-trichloroethane - a widely used, very persistent pesticide in the chlorinated hydrocarbon group, now banned from production and use in Canada and many countries. DDE is a metabolic product of DDT. DDE is linked to eggshell thinning in several Great Lakes bird species.
dissolved oxygen
The amount of oxygen dissolved in water. See ANOXIA and BOD........................
dissolved oxygen
diversion
Transfer of water from one watershed to another.
diversion
diversity
Diversity can be defined as the number of different organisms and their relative frequency of occurrence in a given area. Diversity describes the variety and variability among ecosystems and communities, including composition, function, and structure. Concerns about habitat fragmentation fall within the scope of structural diversity..elative to each other in time and in space. It includes the size, shape, and distribution of populations, habitats, and communities across the landscape. Concerns about habitat fragementation fall within the scope of structural diversity..........
diversity
drainage basin
A waterbody and the land area drained by it. Drainage basins are defined by topographic boundaries that determine the direction of water flows into a water body. Synonymous with watershed..c boundaries that determine water flows into a water
body.
drainage basin
ecoregion
An area of the earth surface characterized by distinct ecological responses to climate as expressed by the development of vegetation, soil, water and fauna...
ecoregionbasin
ecosystem
The interacting complex of living organisms and their non-living environment. The biotic community and its abiotic environment are considered together as a unit. Ecosystems are characterized by a flow of energy that sets up trophic structure and material cycling.
ecosystem
ecotone
A boundary transition area between two ecosystems. This definition is usually applied to vegetation in terrestrial systems.
ecotone
ecozone
An area of the earth surface representative of large and very generalized ecological units characterized by interactive and adjusting abiotic and biotic factors....
ecozone
effluent
Waste waters discharged from industrial or municipal sewage treatment plants.
effluent
endangered
A species threatened with imminent extinction or extirpation throughout all or a significant portion of its range....
endangered
endocrine disruptor
An environmental endocrine disruptor is a chemical agent that interferes with the synthesis, secretion and actions of natural hormones in the body. Hormones are responsible for the maintenance of reproduction, development, behaviour and homeostasis.
ENDOCRINE DISRUPTING CHEMICALS
There is substantial evidence that adverse health effects have occurred in wildlife species upon exposure to chemicals in the environment that interact with endocrine systems. Scientists working for the Canadian Wildlife Service (CWS) have been studying the effects of endocrine disrupting compounds (EDCs) and other toxic substance on Great Lake wildlife for approximately 25 years.
The U.S. EPA definition of an EDC: "An EDC is an exogenous agent that interferes with the production, release, transport, metabolism, binding, action or elimination of natural hormones in the body responsible for the maintenance of homeostasis and regulation of developmental processes".
The most important question that must be addressed is: "Are local wildlife populations currently being adversely affected by exposure to environmental contaminants which cause effects that are mediated through endocrine systems?" To address this question, three endocrine-controlled functions are considered: (i.) reproduction, (ii.) development and growth and (iii.) immunocompetence .
Between 1970 and 1995, scientists and their collaborators documented the following in Great Lakes wildlife:
* Reproductive failure in several species of fish-eating birds due to thinning of eggshells, embryotoxicity and/or inadequate parental behaviour (1970s).
* A female-biased sex ratio in adult herring gulls and feminization of herring gull embryos in Lake Ontario (1970s).
* Developmental abnormalities in several species of birds and snapping turtles (early 1970s - 1994).
* Wasting Syndrome in Caspian tern, Forster's tern and herring gull chicks (early 1970s - 1992).
* Goitre (1974-1983) and low levels of thyroid hormones (1991) in herring gulls.
* Thymic atrophy in herring gull chicks (1992) and a decrease in T-cell-mediated immunity in Caspian tern and herring gull chicks (1992-1995).
There is evidence that these effects were caused by persistent and bioaccumulative halogenated hydrocarbons including DDE, polychlorinated biphenyls (PCBs), hexachlorobenzene and 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). Experimental studies supported this hypothesis.
The incidence of reproductive failure and developmental abnormalities in wildlife has decreased as the degree of contamination of the food chain has declined, but some species, including terns, bald eagles and snapping turtles continue to have problems that appear to be caused by contaminants. The use of more sensitive measures, such as immune function suggests that current levels of contamination at some sites are affecting fish-eating birds.
Current Research
* The effects of environmental contaminants on the hypothalmo-pituitary-adrenal axis in wild birds;
* Studies are being carried out in collaboration with the University of Guelph to determine if organochlorines or other environmental contaminants are affecting embryo development, plasma hormone levels and secondary sexual characteristics in snapping turtles at various sites on the Great Lakes ;
* The effects of chlorinated hydrocarbons and pesticides used in Great Lakes Areas of Concern and in apple orchards on reproduction, hormone levels, testicular histology and immune function in tree swallows;
* The effects of PCBs and other contaminants on reproductive success, gonadal morphology and plasma hormone levels in common terns nesting along the St. Lawrence River near Massena, New York;
* Studies to investigate the effects of PCBs and other contaminants on immune function in herring gulls and Caspian terns;
* Investigation of the implications of low plasma thyroxine and vitamin A levels on reproduction and development of herring gulls;
* Collaborative investigations on the anti-androgenic effects of DDE on male birds and of the effects of a variety of contaminants and pesticides on the stress response;
Studies on the in vitro metabolism of testosterone in herring gull tissues.
St. Lawrence River
* Studies on the effects of pesticides on sperm quality in frogs;
* Endocrine-disrupting effects of PCBs and PAHs on mudpuppies in contaminated areas of the St. Lawrence River;
* Studies in the laboratory and in outdoor mesocosms to determine the effects of pesticides on the development and reproduction of frogs;
* Effects of organic contaminants on great blue herons are being investigated by measuring reproductive success and development, and levels of thyroid hormones and retinoids in plasma.
While exposure to acutely toxic agents at lethal levels may disrupt reproduction and limit genetic variability, exposure to EDCs at critical times of development or reproduction may pose the greatest threat to the diversity and long-term survival of sexually-reproducing organisms. Such agents (which may be persistent or relatively non-persistent) can affect the degree of genetic variability that exists within a population, the inter-generational transfer of that variability, and the size, functional viability and genetic variability of future generations. Although the effects of EDCs may be subtle, their cumulative stress may be greatest on long-lived, slowly reproducing species. Without human intervention to counteract these impacts, species may decline or be lost.
To bring the maximum breadth and multi-disciplinary expertise to bear on this issue, we will continue to forge national and international links and strengthen collaborations among scientists. Future research will focus on: "hot spots", sensitive species, and developing new methods for predicting the effects of EDCs on wildlife:
* Strengthen efforts to determine the effects of chlorinated hydrocarbons and EDCs in agricultural run-off and on reptiles and amphibians in major wetlands.
* Participate in studies on the effects of EDCs on sensitive mammalian species (eg. mink, otter).
* Examine the effects of chemicals on the stress response in birds.
* Develop new methods to determine the effects of EDCs on embryo development in birds.
* Develop in vitro methods for predicting interspecies differences in sensitivity to EDCs.
* Contributing to regulatory efforts to broaden testing of products to include screening for endocrine-modulating activity in vitro, and multigeneration reproductive studies to reduce environmental exposures to EDCs, both in Canada and globally.
endocrine disruptor
EPA - Environmental Protection Agency, an American agency with the mandate to protect the environment including the Great Lakes basin.
epilimnion
The warm, upper layer of water that occurs in a lake during summer stratification.-
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erosion
The wearing away and transportation of soils, rocks and dissolved minerals from the land surface or along shorelines by rainfall, running water, or wave and current action..
erosion
eutrophication
The process of fertilization that causes high productivity and biomass in an aquatic ecosystem. Eutrophication can be a natural process or it can be a cultural process accelerated by an increase of nutrient loading to a lake by human activity..
eutrophication
exotic species
Species that are not native to a geographic region or watershed and have been intentionally introduced or have inadvertently infiltrated the system.
exotic species
extinct
A species formerly indigenous to the Great Lakes that no longer exists anywhere....
extinct
extirpated
A species no longer existing in the Great Lakes but occurring elsewhere.
extirpated
fauna
The animals that live in a given area. Fauna include animals from the smallest fish to the largest elephant.
fauna
flora
flora
All the plants in a given area from the smallest algae to the largest tree..
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food web
The process by which organisms in higher trophic levels gain energy by consuming organisms at lower trophic levels..O
food web
gene pool
The genetic material of a localized interbreeding population.
gene pool
glossary
The definition of technical words included in this report
glossary
Great Lakes Fishery Commission
In 1955 the binational Great Lakes Fishery Commission was established to find a means of control for the sea lamprey. During the 1950s and 1960s, fisheries problems on the Great Lakes became critical. The parasitic sea lamprey had decimated fisheries as it invaded further into the waterway. By the late 1970s the lamprey population had been reduced by 90 percent with use of selective chemicals to kill the larvae in streams. Since then, the Fishery Commission has expanded its activities to include work to rehabilitate the fisheries of the lakes coordinating government efforts to stock and restore fish populations.......
Great Lakes Fishery Commission
habitat
The arrangement in space of the resources required to meet the needs of a given species. Also, the area or locality used by a population of organisms and the place where they live. Also the sum of environmental conditions of a specific place occupied by a species or a population.
habitat
human health
The state of complete physical, mental and social well-being and not merely the absence of disease or infirmity (World Health Organization)..
human health
hydrologic cycle
The natural cycle of water on earth, including precipitation as rain and snow, runoff from land, storage in lakes, streams, and oceans, and evaporation and transpiration (from plants) into the atmosphere...
hydrologic cycle
hypolimnion
The cold, dense, lower layer of water that occurs in a lake during summer stratification.
hypolimnion
indigenous
Originating in and characterizing a particular region or country. A plant or animal species native to a region.
indigenous
landscape
Multiple ecosystems that interact with each other, including aquatic ecosystems, wild-land ecosystems, and human-dominated ecosystems.
landscape
layering
The tendency in deep lakes for distinct layers of water to form as a result of vertical change in temperature and therefore in the density of water. See also EPILIMNION, HYPOLIMNION, THERMOCLINE
layering
leachate
Materials suspended or dissolved in water and other liquids, usually from waste sites, which percolate through soils and rock layers..a
leachate
macrophyte
macrophyte
A large plant easily visible without a microscope.eeee
marsh
marsh
A wetland dominated by non-woody vegetation that emerges above the soil or water.
mass balance
An approach to evaluating the source, transport and fate of contaminants entering a water system as well as their effects on water quality.
mass balance
mesotrophic
See TROPHIC STATUS
mesotrophic
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trophic status
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migration corridor
A belt, band, or stringer of vegetation that provides a completely or partially suitable habitat and which animals follow during migrations.
migration corridor
migration route
A travel route used routinely by wildlife in their seasonal movements from one habitat to another.
migration route
Migratory Birds Convention Act
Migratory Birds Convention Act
An act to implement a convention for the protection of migratory birds and their nests in Canada and the United States.
mixedwood plains ecozone
The Mixedwood Plains ecozone is located in the Windsor-Quebec City corridor. The ecozone, that contains Canada's two largest cities, Montreal and Toronto, has a population density of over 100 persons per square kilometre - 10 times higher than anywhere else in Canada.
sor - Quebec
City corridor, or Mixedwood Plains ecozone. About 54% of all
Canadians live here. The ecozone, which contains the country's two
largest cities, has a population density of over 100 persons per
square kilometre - 10 times higher than anywhere else in Canada.
mixedwood plains ecozonee
monoculture
monoculture
An agricultural practice that is based on a single type of crop. This term is now being applied to forestry and fishery.
native species
Plant and animal species present in an area before the arrival of European immigrants after the year 1498.
native species
NAWMP
NORTH AMERICAN WATERFOWL
MANAGEMENT PLAN
The 1994 goal of the plan is to restore continental waterfowl populations to numbers seen in the 1970s. The plan call for 11.1 million acres of wetlands and associated uplands to be protected and 14.7 million acres to be restored or enhanced...
NAWMP
nearshore
A unique and dynamic intersection between life on land and life in the water. It includes coastal ecosystems both on land and in the water. The land areas are those ecosystems directly affected by the lakes. The water areas are the relatively warm shallow areas near the shore. The nearshore are includes coastal wetlands that are dependent on lake levels....
nearshore
nonpoint source
Source of pollution in which pollutants are discharged over a widespread area or from a number of small inputs rather than from distinct, identifiable sources.
nonpoint source
NPRI - National Pollutant Release Inventory. This inventory contains information on total releases and transfers of toxic pollutants.
Data were obtained from Environment Canada's National Pollutant Release inventory (NPRI) and USEPA's Toxic Release Inventory (TRI). Both the NPRI and TRI are publicly available databases that contain national data regarding on-site releases and off-site transfers of substances in waste from industrial facilities. This data is collected and grouped by facility and by substance.
nutrient
Chemical that is an essential raw material for the growth and development of an organism..
nutrient
old growth
A stand of trees that is past full maturity or normal rotation age, and shows decadence, including gaps, snags, large fallen logs and tree cavitites. The last stage in forest succession.
old growth
oligotrophic
See TROPHIC STATUS
oligotrophic
trophic status
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pathogens
Disease-causing agents such as bacteria, viruses and parasites.
pathogens
Polychlorinated biphenyls - A class of persistent toxic organic chemicals that bioaccumulate in the tissues of organisms. To know more about PCBs please click here.
photosynthesis
A process occurring in the cells of green plants and some micro-organisms in which solar energy is transformed into stored chemical energy..g
photosynthesis
phytoplankton
Minute, microscopic aquatic plant life (see ALGA).
phytoplankton
point source pollution
A source of pollution that is distinct and identifiable, such as an outfall pipe from an industrial plant..
point source pollution
pollution prevention
pollution prevention
Pollution prevention is a strategy that aims to eliminate the causes of pollution rather than treating the symptoms by shifting efforts from "controlling" pollution to "preventing" it.
polychlorinated biphenyls
polychlorinated biphenyls
A class of persistent organic chemicals that bioaccumulate.
population
A collection of individuals of the same species living in a prescribed area that share the same gene pool.
population
primary productivity
The conversion of sunlight and nutrients into plant material through photosynthesis.,and the
subsequent conversion of this plant material into animal matter.y
primary productivity
productivity
The conversion of sunlight and nutrients into plant material through photosynthesis, and the subsequent conversion of this plant material into animal biomass.y
productivity
release
release
A release is an on-site discharge of a substance to the environment from a facility (e.g., of pulp and paper mills, steel mills, or municipal waste water treatment plants). This includes releases to water, air, land, and to underground wells by injection.
resuspension
The remixing of sediment particles and pollutants back into the water column by storms, currents, organisms and human activities such as dredging or shipping.
resuspension
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retention time
The time required to exchange all the water in a lake.
retention time
riparian zone
An area identified by the presence of vegetation that requires more moisture than normally found in the area. Also the area of vegetative cover immediately adjacent to water, e.g., the shoreline of a river.
riparian zone
secondary productivity
The conversion of plant material into animal biomass.......l through photosynthesis, and the subsequent conversion of this plant material into animal matter.
secondary productivity
sediment resuspension
sediment resuspension
The remixing of sediment particles and pollutants back into the water by storms, currents, organisms and human activities such as dredging or shipping.
seiche
An oscillation in water level from one end of a lake to another due to rapid changes in winds and atmospheric pressure. Most dramatic after an intense but local weather disturbance passes over one end of a large lake.
seiche
special concern species
A species that has unique or highly specific habitat requirements or is particularly sensitive to disturbance and deserves careful monitoring of its status. A species that is not currently classified as endangered or threatened..or it has unique or highly specific habitat requirements, or is particularly sensitive to disturbance and deserves careful monitoring of its status.
special concern species
species
Individuals that can reproduce with each other and can generate fertile offspring. A species is typically composed of complexes of populations and subspecies..{
species
stand
Plant communities, particularly of trees, sufficiently uniform in composition, age, spatial arrangement, or condition to be distinguishable from adjacent communities.
stand
stratification
The tendency in deep lakes for distinct layers of water to form as a result of vertical change in temperature and therefore in the density of water. See also EPILIMNION, HYPOLIMNION, THERMOCLINEEE
stratification
subspecies
Populations of a species that differ in genetic make-up from other populations of the same species.
subspecies
sustainability
sustainability
Long term management of ecosystems to meet the needs of present human populations without interruption, weakening, or loss of the resource base for future generations...
thermal bar
thermal bar
The thermal structure of the water column also influences water movement in Lake Ontario. During the spring, shallow nearshore waters warm faster than the deep offshore waters creating a temperature discontinuity called a thermal bar. The thermal bar prevents mixing of the relatively warm nearshore waters and the cold offshore waters while it persists. As spring heating continues, the thermal bar moves up to 20-25 km off the north shore and about 10 km off the south shore and then dissipates about mid-June when lakewide horizontal stratification begins (Stevens 1988). During periods of thermal bar, persistant pollutants may be trapped in a narrow band around the perimeter of the lake. Water quality can be noticeably degraded in a "ring of pollution" compared with offshore waters (Boyce et al. 1989). This ring of pollution has potential implications for the health of aquatic organisms since many, such as fish, move inshore during the spring to reproduce and so may be exposed to harmful concentrations of chemicals during a critical phase in their life cycle................
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thermocline
A layer of water in deep lakes separating the cool hypolimnion (lower layer) from the warm epilimnion (surface layer)..
thermocline
threatened species
A species that is likely to become endangered within the foreseeable future throughout all or a significant part of its range.
threatened species
toxic substance
As defined in the Great Lakes Water Quality Agreement, any substance that adversely affects the health or well-being of any living organism.
toxic substance
toxin
toxin
A chemical, physical, or biological agent that causes disease or some alteration of the normal structure and function of an organism. Onset of effects may be immediate or delayed, and impairments may be slight or severe.
The U.S. EPA has created a TRI (Toxic Release Inventory). This inventory contains information on total releases and transfers of toxic pollutants.releases and transfers of toxic pollutants.
trophic status
A measure of the biological productivity in a body of water. Aquatic ecosystems are characterized as oligotrophic (low productivity), mesotrophic (medium productivity) or eutrophic (high productivity).
trophic status
volatilization
volatilization
The transfer of chemical elements (oxygen, contaminants, water vapour) from the surface of a water body to the atmosphere. In the case of toxic contaminants, this process reduces the amount of contaminants in water but it increases it in the atmosphere. These contaminants can then be transported over long distances and then precipitate and pollute distant ecosystems..
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watershed
watershed
See drainage basin..
wetland
An area where water is at, near, or above, the land surface for a sufficent length of time to be able to support aquatic or hydrophytic vegetation and whose soils are hydric or indicative of wet conditions.
wetland
wetland complex
wetland complex
A group of wetlands that are biologically connected because of their close proximity, creating a mosaic of habitat for wetland species.
wind set up
A local rise in water levels caused by winds pushing water to one side of a lake.
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