Bi-national assessment of the Great Lakes: SOLEC partnerships

Many administrative jurisdictions have authority over parts of the Great Lakes, sometimes with competing purposes as well as governance at differing scales of time and space. As demand increases for high quality information that is relevant to environmental managers, environmental and natural resource agencies with limited budgets must look to interdisciplinary, collaborative approaches for the collection, analysis and reporting of data. The State of the Lakes Ecosystem Conferences (SOLEC) were begun in 1994 in response to reporting requirements of the Great Lakes Water Quality Agreement between Canada and the U.S. The biennial conferences provide independent, science-based reporting on the state of health of the Great Lakes ecosystem components. A suite of indicators necessary and sufficient to assess Great Lakes ecosystem status was introduced in 1998, and assessments based on a subset of the indicators were presented in 2000. Because SOLEC is a multi-agency, multi-jurisdictional reporting venue, the SOLEC indicators require acceptance by a broad spectrum of stakeholders in the Great Lakes basin. The SOLEC indicators list is expected to provide the basis for government agencies and other organizations to collaborate more effectively and to allocate resources to data collection, evaluation and reporting on the state of the Great Lakes basin ecosystem.     

A process for selecting indicators for monitoring conditions of rangeland health

This paper reports on a process for selecting a suite of indicators that, in combination, can be useful in assessing the ecological conditions of rangelands. Conceptual models that depict the structural and functional properties of ecological processes were used to show the linkages between ecological components and their importance in assessing the status and trends of ecological resources on a regional scale. Selection criteria were developed so that relationships could be assessed at different spatial scales using ground and aerial measurements. Parameters including responsiveness and sensitivity to change, quality assurance and control, temporal and spatial variability, cost-effectiveness and statistical design played an important role in determining how indicators were selected. A total of ten indicator categories were selected by a committee of scientists for evaluation in the program. A subset that included soil properties, vegetation composition and abundance, and spectral properties was selected for evaluation in a pilot test conducted in 1992 in the Colorado Plateau region of the southwestern United States. This work is part of a major effort being undertaken by the U.S. Environmental Protection Agency and its collaborators to assess the condition of rangelands (primarily comprised of arid, semi-arid and dry subhumid ecosystems) along with seven other ecosystem groups (forests, agricultural lands, wetlands, surface waters, landscapes, estuaries and Great Lakes) as part of a national Environmental Monitoring and Assessment Program (EMAP). The indicator selection process reported upon was developed to support EMAP's goal of providing long-term, policy-relevant research focusing on evaluating the ecological condition (or health) of regional and national resources.     

Environmentally stratified sampling design for the development of Great Lakes environmental indicators

Understanding the relationship between human disturbance and ecological response is essential to the process of indicator development. For large-scale observational studies, sites should be selected across gradients of anthropogenic stress, but such gradients are often unknown for a population of sites prior to site selection. Stress data available from public sources can be used in a geographic information system (GIS) to partially characterize environmental conditions for large geographic areas without visiting the sites. We divided the U.S. Great Lakes coastal region into 762 units consisting of a shoreline reach and drainage-shed and then summarized over 200 environmental variables in seven categories for the units using a GIS. Redundancy within the categories of environmental variables was reduced using principal components analysis. Environmental strata were generated from cluster analysis using principal component scores as input. To protect against site selection bias, sites were selected in random order from clusters. The site selection process allowed us to exclude sites that were inaccessible and was shown to successfully distribute sites across the range of environmental variation in our GIS data. This design has broad applicability when the goal is to develop ecological indicators using observational data from large-scale surveys.     

Current Status and Temporal Trends in Concentrations of Persistent Toxic Substances in Sport Fish and Juvenile Forage Fish in the Canadian Waters of the Great Lakes

This paper presents a summary of the current status and temporal trends over the past 15 - 20 years in contaminant levels in sport fish and juvenile forage fish in the Canadian waters of the Great Lakes. Fish consumption advisories summarized from the 1995 Guide to Eating Ontario Sport Fish showed that 67% of the 1736 consumption advisories in the Canadian waters of the Great Lakes had no restrictions. In the remaining 33% of the advisories, consumption of sport fish was restricted to 4 meals per month or less. Lake Erie had the fewest consumption restrictions (19%) and Lake Ontario the most (45%). PCBs were the principal contaminants of concern responsible for 47% of the consumption restrictions in the Canadian waters of the Great Lakes and caused the most consumption restrictions in each of the Great Lakes except Lake Superior where toxaphene caused 69% of the consumption restrictions. Concentrations of PCBs in sport fish declined in Lake Huron and Lake Ontario over the period 1976-1994. A decline in mirex concentrations in sport fish from Lake Ontario was also observed over the same time period. Concentrations of Hg in sport fish from Lake St. Clair declined over the period 1970-1994, but mercury in sport fish showed no trend over time in Lake Huron or Lake Ontario over the period 1981-1994. Contaminant levels in juvenile forage fish collected in 1993 and 1994 at 44 locations in the lower Great Lakes were assessed against wildlife protection guidelines. Concentrations that exceeded the Forage Fish Contaminant Index were observed at 17 locations with PCBs being the principal contaminant of concern. PCB concentrations in spottail shiners declined at 12 of 16 locations monitored in the lower Great Lakes over the period 1975-1994.     

Designing the Environmental Results Workshop: Historical Context, Causality and Candidate Species

During the past thirty years, researchers have been documenting the concentrations and effects of persistent toxic substances, such as DDT, PCBs, dioxins and furans, in populations of Great Lakes organisms. In designing the International Joint Commission's Workshop on Environmental Results, the organizers on the Great Lakes Science Advisory Board started from the premise that the selection of indicator organisms for long-term trend analysis requires that the causal relationships between the observed effects and the putative cause should be demonstrated and believed. However, the causal relationships that have been documented have generally been met with skepticism by fellow scientists and by regulatory officials resulting in no agreement on valid indicator organisms. To overcome this skepticism, wildlife, fisheries and human health researchers have adapted the epidemiological criteria used by medical and veterinary researchers for synthesizing the causal evidence. Brief reviews of several candidate species and of their suitability as long term monitors are presented, and the adequacy of monitoring programs for determining trends in the incidence of chemically-induced effects is assessed.     

Reproductive and Physiological Effects of Environmental Contaminants in Fish-Eating Birds of the Great Lakes: A Review of Historical Trends

During the 1950s and 1960s, reproductive failures and population declines were observed in fish-eating birds such as gulls, terns, cormorants, herons, and eagles in the Great Lakes. DDE-induced eggshell thinning contributed to these declines, but other factors such as embryo toxicity also were implicated. With reduced releases of many pollutants, reproduction recovered in some species. However, biomonitoring during the 1980s and 1990s indicates continuing effects at highly contaminated sites. Improved analytical techniques and bioassays have allowed the assessment of the total dioxin-like toxicity of complex mixtures of organochlorines (TCDD-equivalents). Developmental defects such as embryo mortality, deformities, and edema have been associated with dioxin-like PCBs in several avian species. Improved biochemical techniques have allowed the measurement of biomarkers that detect physiological alterations associated with contaminants. Specific biomarkers studied in Great Lakes birds include cytochrome P-450 monooxygenases, highly carboxylated porphyrins, thyroxine, vitamin A, and immune function. Reproductive and physiological alterations are associated with population-level effects in Caspian terns and bald eagles that feed on highly contaminated fish. Biomonitoring using biomarkers and population-level measures in fish-eating birds will continue to be important for assessing the effects of contaminants on the Great Lakes ecosystem.     

A spatial hierarchical framework for the co-management of ecosystems in Canada and the United States for the upper Great Lakes region

Over the past three decades, considerable effort has been invested in the development of complex and comprehensive ecosystem classifications and inventories in many parts of North America. Paralleling this has been an evolution in those hierarchical frameworks guiding the development and application of classifications. However, resource management agencies continue to grapple with the dilemma of applying multiple classification and inventory templates over large jurisdictions, especially as they attempt to address ecosystem management objectives. Given that Canada and the United States share ecosystems and that commitments have been made by all levels of government to make progress towards ecosystem-based approaches to management, there is a need to provide the proper tools. Comprehensive goals will not be achieved without collaboration and cooperation.This paper outlines the range of ecosystem classification approaches that exist in the Upper Great Lakes region. Canadian and American national hierarchical frameworks are briefly examined. Specific information needs and tasks are outlined which must be followed, independent of national boundaries, for the successful integration of planning and monitoring programs for large regional ecosystems.A general model is proposed for the development and application of an integrated, multi-scale and bi-national ecosystem classification, inventory and information system. This approach would facilitate data sharing and communication across jurisdictional boundaries.     

Trends in Concentrations and Effects of Persistent Toxic Contaminants in the Great Lakes: Their Significance for Inferring Cause-Effect Relationships and Validating Management Actions

This paper summarizes a workshop on temporal trends in levels and effects of persistent toxic contaminants in the North American Great Lakes. Information on trends in contaminant levels is reasonably good for sediments, fish, and birds, but is scanty or absent for other ecosystem components. Information on trends in effects has been reported for birds, but is scanty or absent for other groups of organisms. In principle, information on differential trends in effects of contaminants could be used to validate or improve hypotheses about cause-effect relationships and to verify the effectiveness of management actions. However, little or no useful information on differential trends appears to be available. Use of trend data for these purposes will require collection of more detailed information and greater attention to conceptual formulation of hypotheses.     

Great Lakes monitoring results--comparison of probability based and deterministic sampling grids

The Great Lakes may be viewed as a coastal environment, affected by the same meteorological and physical forces as the coastal ocean. The U.S. EPA, Great Lakes National Program Office (GLNPO) has monitored the open waters of the lakes, annually, since 1983. As part of the U.S. EPA Environmental Monitoring and Assessment Program (EMAP), a pilot study was performed in Lake Michigan to compare the existing GLNPO deterministic sampling grid with the EMAP probabilistic grid. Results of chemical analyses of trophic status indicators (total phosphorus and chlorophyll a) as well as nutrients and conventional limnological measurements, from spring and summer surveys in 1992 indicate little difference between the grids in the offshore region of the lake. The few statistically significant differences may be due to station distribution throughout the lake, or simple chance. This might be expected due to the well mixed nature of the open waters of Lake Michigan. The detection of a long-term trend for total phosphorus in Lake Michigan benefits from an annual program: viewing cumulative frequency distributions based on a four year EMAP interval does not convey information on the decrease in phosphorus in the lake. If the EMAP sampling grid were to be used in the Great Lakes, pilots in each of the lakes would be necessary for utilization of the existing long-term record as a basis for trend detection.     

Dose equivalent commitments from fallout radionuclides in the open waters of the Great Lakes. 1973–1981

The levels of ¹⁴⁴Ce, ¹³⁷Cs, ¹²⁵Sb, and ⁹⁰Sr in the open waters of the Great Lakes were measured over the period 1973–81. The levels were found to be very low. ¹⁴⁴Ce was detected only up to 1975 after which it dropped below the detection limit. The data indicate that the concentrations of the remaining three radionuclides have decreased with time. ⁹⁰Sr and ¹³⁷Cs provide essentially all of the radiological dose from drinking Great Lakes water. The dose equivalant commitments have been calculated from these measurements and found to be well within the Great Lakes Water Quality Agreement's water quality objective for radioactivity.     

Monitoring the Elimination of Persistent Toxic Substances from the Great Lakes; Chemical and Physiological Evidence from Adult Herring Gulls

To assess progress towards virtual elimination of PCBs, DDE, dieldrin and Mirex and their associated physiological effects, we compared their concentrations in pooled livers of adult herring gulls (Larus argentatus) repeatedly sampled at 8 Great Lakes colonies and a reference colony on the Atlantic coast between 1974 and 1993. We measured the relative thyroid mass and concentrations of highly carboxylated porphyrins and retinyl palmitate in the liver of each individual. PCBs, dieldrin and mirex declined in 7 of 8 colonies while DDE decreased in six. The greatest decreases occurred pre-1985. PCBs and DDE did not decrease in gulls from Middle Island in western L. Erie. Middle Island and Saginaw Bay had the highest concentrations of PCBs of 11 Great Lakes colonies in the 1990s. Thyroids of gulls from Great Lakes colonies were slightly enlarged but the degree of enlargement has decreased over time. In 1991, gulls from Great Lakes colonies had slight to moderately elevated concentrations of highly carboxylated porphyrins. In the early 1990s, hepatic stores of retinyl palmitate were very seriously depleted in gulls from the Detroit River, western basin of Lake Erie, and Lake Ontario, reflecting decreased availability and altered storage. We conclude that PCBs and/or other persistent toxic substances in the food of herring gulls have not been virtually eliminated.     

Ecological Monitoring for Assessing the State of the Nearshore and Open Waters of the Great Lakes

The Great Lakes Water Quality Agreement stipulates that the Governments of Canada and the United States are responsible for restoring and maintaining the chemical, physical and biological integrity of the waters of the Great Lakes Basin Ecosystem. Due to varying mandates and areas of expertise, monitoring to assess progress towards this objective is conducted by a multitude of Canadian and U.S. federal and provincial/state agencies, in cooperation with academia and regional authorities. This paper highlights selected long-term monitoring programs and discusses a number of documented ecological changes that indicate the present state of the open and nearshore waters of the Great Lakes.     

Spatial and Temporal Trends in Organochlorine Contamination and Bill Deformities in Double-Crested Cormorants (Phalacrocorax Auritus) from the Canadian Great Lakes

The levels of organochlorine contaminants (OCs) in the eggs of double-crested cormorants (Phalacrocorax auritus) from the Canadian Great Lakes, Lake Nipigon and Lake-of-the-Woods were monitored between 1970 and 1995. PCBs and p,p-DDE were present at the highest concentrations. Significant declines in OC concentrations on the Great Lakes were observed over this period for Lake Ontario, Lake Superior, Georgian Bay and North Channel but not Lake Erie where levels remained relatively stable. In the early 1970s, the greatest OC levels were generally observed in cormorant eggs from nesting sites in Georgian Bay and North Channel of Lake Huron. Between 1984 and 1995 mirex and PCB levels were consistently highest in samples from Lakes Ontario and Erie, respectively. Similar levels of PCDDs and PCDFs were observed from all regions of the Canadian Great Lakes in 1989. In general, OC levels in cormorant eggs between 1984-95 were ranked as follows: Lake Erie>Lake Ontario Lake Superior>Lake Huron. In 1995, eggshell thickness in Canadian Great Lakes cormorants, ranged from 0.423 to 0.440 mm and was on average only 2.3% thinner than pre-DDT era values. Between 1988 and 1996, 31 cormorant chicks with bill defects were observed at 16 different colonies (21% of all colonies surveyed) in Lakes Ontario and Superior, Georgian Bay and North Channel, and the main body of Lake Huron. No bill deformities were observed at reference sites in northwestern Ontario (Lake Nipigon and Lake-of-the-Woods). For the period 1988-96, the prevalence of bill defects in cormorant chicks (0.0 to 2.8/10,000 chicks) did not differ significantly (P > 0.05) among most regions in the Canadian Great Lakes. Georgian Bay was the only region to show a significant decrease in the prevalence of bill defects between the periods 1979-87 and 1988-95.     

The Great Lakes, an Ecosystem Rehabilitated, But Still Under Threat

Since 1972, the Parties (United States and Canada, 1987) to the Great Lakes Water Quality Agreement have been working collaboratively to achieve the purpose of the Agreement “to restore and maintain the chemical, physical and biological integrity of the waters of the Great Lakes Basin Ecosystem”. Billions of dollars and countless person – hours have been expended towards this end, but have the Parties, and their numerous collaborators at the state, provincial, and municipal levels, along with industry and citizen activists achieved meaningful results? This paper will examine the information provided through various monitoring programs and will assess the success of the Parties' programs, and will also discuss the continuing threats to achieving the purpose of the Agreement.     

Air monitoring of persistent organic pollutants in the Great Lakes: IADN vs. AEOLOS

When designing a monitoring campaign, one has to consider many factors in the decision to perform a long-term synoptic monitoring program or a short-term intensive study. Each has its own advantages and disadvantages. This paper compares and contrasts the information obtained from two studies conducted on the Laurentian Great Lakes. One, the Integrated Atmospheric Deposition Network (IADN), is a long-term synoptic monitoring study and the other, the Atmospheric Exchange Over Lakes and Oceans (AEOLOS), was a short-term intensive study. The advantages of long-term synoptic monitoring programs are providing greater spatial information, the relative influence of long and short-range transport on the regional background, gross loadings representative of the majority of each lake and long-term temporal trends. Short-term intensive studies provide more information on the processes governing sources, transport and deposition, such as the urban/industrial influence on adjacent large water bodies, specific sources to an urban/industrial area and short-term fluctuations in concentrations due to meteorology, source strength and photochemical reactions. Using information provided by both the IADN and AEOLOS studies, areas of urban influence are predicted for each of the five Great Lakes.     

Evaluation of Clostridium perfringens as a tracer of sewage contamination in sediments by two enumeration methods

A traditional method of enumerating Clostridium perfringens using membrane filtration (MF) as an indicator of fecal contamination was compared to recently developed rapid method using Rapid Fung Double Tube (RFDT) in an evaluation to characterize the extent of sewage contamination in sediments of the Great Lakes. Evaluation of these two methods included determining C. perfringens concentrations and recovery efficiencies from sewage, sewage-spiked sediments, and water (surface and bottom) and sediment samples collected from two Great Lakes. The RFDT method proved to be a superior method for identifying C. perfringens in lake sediments compared to MF, as it had higher recovery efficiency and was more rapid, reliable, simple, and effective. This study provides biological evidence of the long-term deposition and movement of sewage particulates in the Great Lakes environment and demonstrates the potential usefulness of C. perfringens as a tracer for sewage contamination using a reliable enumeration method.     

Progress Toward Delisting a Great Lakes Area of Concern: The Role of Integrated Research and Monitoring in the Hamilton Harbour Remedial Action Plan

The goal of restoring environmental health and qualities to Hamilton Harbour Great Lakes Area of Concern, an embayment at the western end of Lake Ontario, is considered to be achievable by the year 2015. Restoring Hamilton Harbour is a dynamic process that relies heavily on research and monitoring to direct remediation efforts. Three principle means of coordinating this research and monitoring include: research and monitoring workshops; a monitoring catalogue outlining both government and nongovernment initiatives; and an annual report written by a local community group. These tools increase the effectiveness of remedial actions by: (i) improving stakeholders' ability to track trends; (ii) allowing program decision-makers to utilize adaptive management techniques to continuously modify programs based on new results; (iii) integrating interdisciplinary fields, and (iv) increasing accountability. This paper describes in detail these tools used for coordinating research and monitoring in implementing the Remedial Action Plan of the Hamilton Harbour Great Lakes Area of Concern, along with lessons learned to assist other implementers who are considering similar programs.     

Vegetation, Soil, and Animal Indicators of Rangeland Health

We studied indicators of rangeland health on benchmark sites with long, well documented records of protection from stress by domestic livestock or histories of environmental stress and vegetation change. We measured ecosystem properties (metrics) that were clearly linked to ecosystem processes. We focused on conservation of soil and water as key processes in healthy ecosystems, and on maintenance of biodiversity and productivity as important functions of healthy ecosystems. Measurements from which indicators of rangeland health were derived included: sizes of unvegetated patches, cover and species composition of perennial grasses, cover and species composition of shrubs and herbaceous perennials, soil slaking, and abundance and species composition of the bird fauna. Indicators that provided an interpretable range of values over the gradient from irreversibly degraded sites to healthy sites included: bare patch index, cover of long-lived grasses, palatability index, and weighted soil surface stability index. Indicators for which values above a threshold may serve as an indicator of rangeland health include: cover of plant species toxic to livestock, cover of exotic species, and cover of increaser species. Several other indicator metrics were judged not sensitive nor interpretable. Examples of application of rangeland health indicators to evaluate the success of various restoration efforts supported the contention that a suite of indicators are required to assess rangeland health. Bird species diversity and ant species diversity were not related to the status of the sample site and were judged inadequate as indicators of maintenance of biodiversity.     

Common Patterns of Ecosystem Breakdown Under Stress

Ecosystems, despite their diversity, respond to stress in similar ways. The major pressures which cause the transformation of systems from healthy states to pathological states are classified into four groups: physical restructuring, overharvesting, waste residuals, and the introduction of non-native species. Signs of Ecosystem Distress Syndrome (EDS) are briefly examined in three contrasting ecosystems: desert grasslands, the Great Lakes, and the Baltic Sea. The issue is raised as to the difficulty in discerning between healthy ecosystems, recovering from a natural disturbance, and those ecosystems that have lost their original resilience due to anthropogenic stress. Knowledge of site history and a rigourous monitoring program are important in the evaluation of EDS. An assessment of how ecosystem services are affected is indicative of the consequences to the human component of ecosystems. Management strategies which are employed to mitigate the signs of EDS are usually initiated after resilience is lost or the ecosystem has transformed to an alternate, stress-induced, stable state. It is proposed that preventive strategies measure signs of EDS that serve as early warning signals, combined with "fitness tests" that measure ecosystem response to natural perturbations. The fitness test for ecosystems is based on the premise that unstressed systems are more resilient to natural disturbances than stressed systems.     

Development of the Coastal Intensive Site Network (CISNET)

The U.S. Environmental Protection Agency (EPA), National Oceanic and Atmospheric Administration (NOAA), and National Aeronautics and Space Administration (NASA) have formed a partnership to establish pilot sites for the development of a network known as the Coastal Intensive Site Network (CISNet). CISNet is composed of intensive, long-term monitoring and research sites around the U.S. marine and Great Lakes coasts. In this partnership, EPA and NOAA are funding research and monitoring programs at pilot sites that utilize ecological indicators and investigate the ecological effects of environmental stressors. NASA is funding research aimed at developing a remote sensing capability that will augment or enhance in situresearch and monitoring programs selected by EPA and NOAA. CISNet has three objectives: 1) to develop a sound scientific basis for understanding ecological responses to anthropogenic stresses in coastal environments, including the interaction of exposure, environment/climate, and biological/ecological factors in the response, and the spatial and temporal nature of these interactions, 2) to demonstrate the value of developing data from selected sites intensively monitored to examine the relationships between changes in environmental stressors, including anthropogenic and natural stresses, and ecological response, and 3) to provide intensively monitored sites for development and evaluation of indicators of change in coastal systems.