Because the cumulative effects of many stresses may cause the collapse of a population even when ... more Because the cumulative effects of many stresses may cause the collapse of a population even when the effects of each stress alone may appear insignificant, assessment and prioritization of research needs concerning the effects of multiple stresses on fish and shellfish populations are desirable. Research needs have been developed for laboratory and field experiments and for mathematical methods useful for
ABSTRACT In this report we describe a modification of the Hazard Assessment Rating Methodology (H... more ABSTRACT In this report we describe a modification of the Hazard Assessment Rating Methodology (HARM), a site-screening system developed by the US Air Force for use in the initial phase of its Installation Restoration Program. The Air Force used HARM to evaluate sites of suspected contamination, based on a records search. The new site-rating system (HARM II) utilizes data obtained from preliminary field surveys of sites identified during the records search as being potentially hazardous. HARM II is intended for use in setting priorities for detailed site investigation and possible remedial action. In HARM II, as in HARM and other similar systems, sites are scored on their potential for contaminant transport, on the characteristics of potential contaminant, on the characteristics of and potential receptors along each of several exposure pathways. This report contains (1) methods for estimating benchmarks for human toxicity, ecological toxicity, and bioaccumulation of hazardous chemicals; (2) a detailed description of the HARM II system; and (3) an application of the model to a representative Air Force facility. 6 figs., 26 tabs.
The Workshop on Food-Chain Modeling for Risk Analysis was held in Washington, DC on March 22-24, ... more The Workshop on Food-Chain Modeling for Risk Analysis was held in Washington, DC on March 22-24, 1983. The workshop focused on the aquatic and terrestrial food-chain models currently being used in the risk assessment process. Topics of discussion included (1) models best suited for synfuels risk assessment, (2) best data sources and methods of estimating model input parameters, and (3) limitations inherent in the models used for risk analysis. However, discussions touched on all areas of food-chain modeling for risk assessment. Discussions on the complementary roles of the modeler and the experimentalist, estimation of model uncertainties, and integration of food-chain models with other aspects of the assessment approach were particularly relevant. The workshop concluded that in aquatic food-chain modeling of chronic low-level releases of synfuels effluents, a simple concentration factor approach is appropriate. For terrestrial food-chain models the need for greater model complexity was recognized to account for location-specific variations in agricultural practice, although the estimation of terrestrial transport is also achieved through the use of concentration factors. For both aquatic and terrestrial models, using field data is the best method for estimating concentration factors, but where such data do not exist, laboratory data can be used. If no datamore » exist for a particular compound or class of compounds, estimates can be made using partition coefficients based on structure-activity relationships. Finally, the workshop recognized the need to estimate the uncertainty associated with model output. 60 references, 3 figures, 3 tables.« less
The cumulative effects of multiple stresses on fish and shellfish populations may cause the colla... more The cumulative effects of multiple stresses on fish and shellfish populations may cause the collapse of a population even though the effects of a single stress may be insignificant. Several population modeling approaches are reviewed and compared for their usefulness in quantifying the aggregate effect of multiple sources of stress on populations. Specifically, ways are investigated to insert the effects
Because the cumulative effects of many stresses may cause the collapse of a population even when ... more Because the cumulative effects of many stresses may cause the collapse of a population even when the effects of each stress alone may appear insignificant, it is important to (1) document the effects of multiple stresses on fish and shellfish population, (2) provide an overview of experimental data concerning the effects of multiple stresses on fish and shellfish, and (3)
Aquatic Toxicology and Hazard Assessment: Seventh Symposium
A methodology for assessing toxic effects of chemicals on fish should be able to begin with an em... more A methodology for assessing toxic effects of chemicals on fish should be able to begin with an emission rate, an LCââ, and a description of the receiving system and generate an estimate of the likelihood of reductions in fish populations. This process is a series of extrapolations, each with an associated variance. The LCââ must be extrapolated from the test species to the species of interest, to life-cycle toxicity, to long-term toxicity in the field, to changes in population size due to direct toxic effects and, finally, to the combined direct and indirect toxic effects. Similarly, the emission rate must be converted into an effective environmental concentration in an imperfectly known hydrologic, chemical, physical, and biological system. In this paper we summarize some data and methods for making these extrapolations and indicate sources of uncertainty in each stage of the analysis.
ABSTRACT The species-area pattern for plants and animals predicts larger areas generally contain ... more ABSTRACT The species-area pattern for plants and animals predicts larger areas generally contain greater species richness. Also, it is recognized that the number of species increases from north to south with temperature. Our analyses of the distribution of Michigan fishes support these observations. The common log-log slope value of about 0.25 for species-area relationship was found for the Upper and Lower peninsulas of Michigan as well as the Great Lakes watersheds of Superior, Huron and Erie (Michigan was an exception with a value of 0.44). The number of species per 2500 square kilometers increased from 50 species for the Upper Peninsula to 73 species for the southern Lower Peninsula as the latitude decreased from 47° to 42°, and the Great Lakes watersheds showed a similar pattern. The increase in species number from north to south correlated with a measured increase in growing degree days. The multiple regression of area and growing degree days of watersheds against number of species resulted in an increase in adjusted r2 to 0.67 from 0.38 for the regression of species-area alone. Species diversity of Michigan fishes is strongly influenced by watershed area and growing degree days temperatures.
Models sharing a common bioenergetics framework have been used to address concerns about toxic ch... more Models sharing a common bioenergetics framework have been used to address concerns about toxic chemicals and their effects on the health of aquatic communities. A basic bioenergetics formulation has been expanded to study the dynamics of contaminants in fish, to forecast the fate of polynuclear aromatic hydrocarbons (PAHs) in aquatic systems, to estimate the probable effects of PAHs on production in pelagic systems, and to characterize the interactions between the fates and effects of contaminants. The bioenergetics framework facilitates simulation of the influence of physiological processes on contaminant dynamics and simulation of the modifying effect of contaminants on metabolic processes and ecological interactions. It also permits specification of fates and effects dynamics in terms of parameters that can be experimentally evaluated. The models serve as sets of operational hypotheses about the environmental behavior of xenobiotics and can be used to explore and evaluate the uti...
Description/Abstract This report overviews investigations of the''Lake Acidification an... more Description/Abstract This report overviews investigations of the''Lake Acidification and Fisheries''(LAF) project into the effects of surface water acidification on brook trout (Salvelinus fontinalis) populations. Of the six life stages examined, freshly-fertilized eggs ...
Canadian Journal of Fisheries and Aquatic Sciences, 1986
We quantified the sensitivity of predicted rates of growth and consumption to parameter variation... more We quantified the sensitivity of predicted rates of growth and consumption to parameter variation for models of yellow perch (Perca flavescens), largemouth bass (Micropterus salmoides), and alewife (Alosa pseudoharengus). We used statistical analyses of the results of Monte Carlo simulations to rank parameter importance. The order of parameter importance was model specific, although the results emphasized the need for accurate estimation of the realized fraction of maximum consumption rate (P) and allometric parameters for consumption (a1, b1) and respiration (a2, b2). Excretion and egestion parameters contributed little to prediction errors. The Monte Carlo methods were used to examine the relative importance of parameter variation and diet composition, an external forcing function, on forecasts of alewife growth. If standard deviations of model parameters were known within 2% of their expected values, uncertainty in diet composition could contribute as much as 47% of the variance ...
Because the cumulative effects of many stresses may cause the collapse of a population even when ... more Because the cumulative effects of many stresses may cause the collapse of a population even when the effects of each stress alone may appear insignificant, assessment and prioritization of research needs concerning the effects of multiple stresses on fish and shellfish populations are desirable. Research needs have been developed for laboratory and field experiments and for mathematical methods useful for
ABSTRACT In this report we describe a modification of the Hazard Assessment Rating Methodology (H... more ABSTRACT In this report we describe a modification of the Hazard Assessment Rating Methodology (HARM), a site-screening system developed by the US Air Force for use in the initial phase of its Installation Restoration Program. The Air Force used HARM to evaluate sites of suspected contamination, based on a records search. The new site-rating system (HARM II) utilizes data obtained from preliminary field surveys of sites identified during the records search as being potentially hazardous. HARM II is intended for use in setting priorities for detailed site investigation and possible remedial action. In HARM II, as in HARM and other similar systems, sites are scored on their potential for contaminant transport, on the characteristics of potential contaminant, on the characteristics of and potential receptors along each of several exposure pathways. This report contains (1) methods for estimating benchmarks for human toxicity, ecological toxicity, and bioaccumulation of hazardous chemicals; (2) a detailed description of the HARM II system; and (3) an application of the model to a representative Air Force facility. 6 figs., 26 tabs.
The Workshop on Food-Chain Modeling for Risk Analysis was held in Washington, DC on March 22-24, ... more The Workshop on Food-Chain Modeling for Risk Analysis was held in Washington, DC on March 22-24, 1983. The workshop focused on the aquatic and terrestrial food-chain models currently being used in the risk assessment process. Topics of discussion included (1) models best suited for synfuels risk assessment, (2) best data sources and methods of estimating model input parameters, and (3) limitations inherent in the models used for risk analysis. However, discussions touched on all areas of food-chain modeling for risk assessment. Discussions on the complementary roles of the modeler and the experimentalist, estimation of model uncertainties, and integration of food-chain models with other aspects of the assessment approach were particularly relevant. The workshop concluded that in aquatic food-chain modeling of chronic low-level releases of synfuels effluents, a simple concentration factor approach is appropriate. For terrestrial food-chain models the need for greater model complexity was recognized to account for location-specific variations in agricultural practice, although the estimation of terrestrial transport is also achieved through the use of concentration factors. For both aquatic and terrestrial models, using field data is the best method for estimating concentration factors, but where such data do not exist, laboratory data can be used. If no datamore » exist for a particular compound or class of compounds, estimates can be made using partition coefficients based on structure-activity relationships. Finally, the workshop recognized the need to estimate the uncertainty associated with model output. 60 references, 3 figures, 3 tables.« less
The cumulative effects of multiple stresses on fish and shellfish populations may cause the colla... more The cumulative effects of multiple stresses on fish and shellfish populations may cause the collapse of a population even though the effects of a single stress may be insignificant. Several population modeling approaches are reviewed and compared for their usefulness in quantifying the aggregate effect of multiple sources of stress on populations. Specifically, ways are investigated to insert the effects
Because the cumulative effects of many stresses may cause the collapse of a population even when ... more Because the cumulative effects of many stresses may cause the collapse of a population even when the effects of each stress alone may appear insignificant, it is important to (1) document the effects of multiple stresses on fish and shellfish population, (2) provide an overview of experimental data concerning the effects of multiple stresses on fish and shellfish, and (3)
Aquatic Toxicology and Hazard Assessment: Seventh Symposium
A methodology for assessing toxic effects of chemicals on fish should be able to begin with an em... more A methodology for assessing toxic effects of chemicals on fish should be able to begin with an emission rate, an LCââ, and a description of the receiving system and generate an estimate of the likelihood of reductions in fish populations. This process is a series of extrapolations, each with an associated variance. The LCââ must be extrapolated from the test species to the species of interest, to life-cycle toxicity, to long-term toxicity in the field, to changes in population size due to direct toxic effects and, finally, to the combined direct and indirect toxic effects. Similarly, the emission rate must be converted into an effective environmental concentration in an imperfectly known hydrologic, chemical, physical, and biological system. In this paper we summarize some data and methods for making these extrapolations and indicate sources of uncertainty in each stage of the analysis.
ABSTRACT The species-area pattern for plants and animals predicts larger areas generally contain ... more ABSTRACT The species-area pattern for plants and animals predicts larger areas generally contain greater species richness. Also, it is recognized that the number of species increases from north to south with temperature. Our analyses of the distribution of Michigan fishes support these observations. The common log-log slope value of about 0.25 for species-area relationship was found for the Upper and Lower peninsulas of Michigan as well as the Great Lakes watersheds of Superior, Huron and Erie (Michigan was an exception with a value of 0.44). The number of species per 2500 square kilometers increased from 50 species for the Upper Peninsula to 73 species for the southern Lower Peninsula as the latitude decreased from 47° to 42°, and the Great Lakes watersheds showed a similar pattern. The increase in species number from north to south correlated with a measured increase in growing degree days. The multiple regression of area and growing degree days of watersheds against number of species resulted in an increase in adjusted r2 to 0.67 from 0.38 for the regression of species-area alone. Species diversity of Michigan fishes is strongly influenced by watershed area and growing degree days temperatures.
Models sharing a common bioenergetics framework have been used to address concerns about toxic ch... more Models sharing a common bioenergetics framework have been used to address concerns about toxic chemicals and their effects on the health of aquatic communities. A basic bioenergetics formulation has been expanded to study the dynamics of contaminants in fish, to forecast the fate of polynuclear aromatic hydrocarbons (PAHs) in aquatic systems, to estimate the probable effects of PAHs on production in pelagic systems, and to characterize the interactions between the fates and effects of contaminants. The bioenergetics framework facilitates simulation of the influence of physiological processes on contaminant dynamics and simulation of the modifying effect of contaminants on metabolic processes and ecological interactions. It also permits specification of fates and effects dynamics in terms of parameters that can be experimentally evaluated. The models serve as sets of operational hypotheses about the environmental behavior of xenobiotics and can be used to explore and evaluate the uti...
Description/Abstract This report overviews investigations of the''Lake Acidification an... more Description/Abstract This report overviews investigations of the''Lake Acidification and Fisheries''(LAF) project into the effects of surface water acidification on brook trout (Salvelinus fontinalis) populations. Of the six life stages examined, freshly-fertilized eggs ...
Canadian Journal of Fisheries and Aquatic Sciences, 1986
We quantified the sensitivity of predicted rates of growth and consumption to parameter variation... more We quantified the sensitivity of predicted rates of growth and consumption to parameter variation for models of yellow perch (Perca flavescens), largemouth bass (Micropterus salmoides), and alewife (Alosa pseudoharengus). We used statistical analyses of the results of Monte Carlo simulations to rank parameter importance. The order of parameter importance was model specific, although the results emphasized the need for accurate estimation of the realized fraction of maximum consumption rate (P) and allometric parameters for consumption (a1, b1) and respiration (a2, b2). Excretion and egestion parameters contributed little to prediction errors. The Monte Carlo methods were used to examine the relative importance of parameter variation and diet composition, an external forcing function, on forecasts of alewife growth. If standard deviations of model parameters were known within 2% of their expected values, uncertainty in diet composition could contribute as much as 47% of the variance ...
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Papers by James Breck