TABLE OF CONTENTS

5.1	THE 1995-1997 PRIORITY
5.1.1	Background
5.1.2	Purpose of LEEMP
5.2	TRANSFER TO THE PARTIES
5.3	FUNDING FOR ONGOING MODEL DEVELOPMENT
5.4	LESSONS LEARNED IN DEVELOPING LEEMP
5.4.1	Background
5.4.2	Lessons
5.5	CONCLUSIONS
5.6	RECOMMENDATIONS
5.7	REFERENCES
5.8	MEMBERSHIP
5.9	APPENDIX: CORE ADVISORY GROUP -- PRIORITY MANAGEMENT ISSUES

Figure 7. Revised Structure, Lake Erie Ecological Model, 1996

5.1 THE 1995-1997 PRIORITY

5.1.1 Background

In 1993, the International Joint Commission (IJC) established the Lake Erie Steering Committee, later called the Lake Erie Task Force , to advise it on the impact of various stressors affecting the health of Lake Erie. In particular, the Task Force focussed its efforts on the adverse effects of stressors on the benthic and fish communities and reported to IJC at its 1995 biennial meeting in Duluth, Minnesota.

In spring 1994, the Task Force convened a telephone conference with modelling and ecosystem experts. They concluded that it was appropriate and possible at this time to initiate development of an ecosystem model for Lake Erie. They also agreed that this was the best approach to gain an understanding of the significant ecological changes occurring in the lake and evaluate the impact of these changes on management decisions affecting the Great Lakes Water Quality Agreement .

In June 1994, the Task Force hosted a modelling "pre-workshop" involving researchers, modellers and managers with an interest in the ecological changes occurring in Lake Erie. Results from this pre-workshop encouraged the Task Force to pursue development of an ecosystem model for the lake. Workshop participants confirmed the need for a Lake Erie model and identified key elements of an approach to model development, including:

• a comprehensive review of existing models, focussing on their scope, linkages and data gaps; and
• development of a stress/response model for zebra mussels to test critical questions and linkages among the various components of the ecosystem.

Participants also recognized the benefit of IJC taking a coordination or leadership role in model development. They stressed the need for involvement from those who would ultimately use the model, including Lake Erie managers within Environment Canada , the United States Environmental Protection Agency (U.S. EPA), state and provincial resource management and environmental control agencies, and others.

In December 1994, the Task Force distributed a "request for proposals" to modellers in the United States and Canada. In January 1995, after evaluating a number of proposals in an open and competitive process, the Task Force initiated the Lake Erie Ecological Modelling Project (LEEMP) by contracting with a binational consulting team consisting of LURA Group from Toronto, Ontario and Dr. Joseph Koonce and Dr. Ana Locci from Case Western Reserve University in Cleveland, Ohio.

5.1.2 Purpose of LEEMP

The purpose of LEEMP was to:

• develop a comprehensive model to enhance understanding of changes taking place in the Lake Erie ecosystem;
• provide a tool to assist Lake Erie resource managers; and
• assist IJC to evaluate progress under the Agreement.

5.2 TRANSFER TO THE PARTIES

The Task Force co-chairs, late in 1995, met with representatives of Environment Canada and U.S. EPA -- two agencies that would be key users of the model and are leading the Lake Erie LaMP (lakewide management plan) process. Specifically, meetings were held with senior representatives from each agency in December 1995, with the Lake Erie LaMP Work Group in January 1996, and with the LaMP Work Group co-chairs in January 1997. To summarize:

• the binational Lake Erie Committee of the Great Lakes Fishery Commission will use and enhance the existing model, which has already been modified to allow a separate focus on the Eastern Basin of Lake Erie, to examine fisheries issues; and
• the Lake Erie LaMP Work Group has created a modelling subcommittee that is using and enhancing this model and others to assist in the development of the Lake Erie LaMP.

Throughout, the Task Force regularly shared its experience in developing LEEMP with agencies involved in the Lake Erie LaMP. This interaction occurred primarily through involvement by LaMP participants in the LEEMP Core Advisory Group, in model development workshops and in working with and testing the model. In fact, the Core Advisory Group provided the Task Force with a list of priority urgent issues that could be addressed by developing the Lake Erie Ecological Model (LEEM) (Appendix). This approach, with its emphasis on sound technical modelling coupled with an interactive, collaborative process for model development, provides an effective blueprint for future model development. The experience in developing a model together with an advisory group, the learning that occurred regarding the uses of the model, the compromise in model resolution and heuristics of model use were all positive. The transfer of the model to the LaMP occurred through the involvement of LaMP participants in the entire process. The Task Force created a much larger nucleus of people working together on ecosystem issues and has crossed boundaries among agencies, offices, communities and disciplines.

5.3 FUNDING FOR ONGOING MODEL DEVELOPMENT

Dr. Koonce, the model's principal investigator, received a substantial U.S. EPA research grant to pursue further model development. The grant, totalling approximately $250,000 (U.S.), is for an overall project entitled "Modelling and Multiobjective Risk Decision Tools for Assessment and Management of Great Lakes Ecosystems" and will enable continued expansion of the Lake Erie model to address issues such as habitat, hydrology and climate change.

In addition, this funding will enable further development of the model to meet the specific needs of the Beneficial Use Impairment Subcommittee under the Lake Erie LaMP. In particular, the Subcommittee has expressed interest in using the model to examine issues such as the effect of water transparency on predator-prey relations, habitat complexity effects, winter die-off of clupeids and in-lake concentrations of phosphorus.

5.4 LESSONS LEARNED IN DEVELOPING LEEMP

5.4.1 Background

Integrated modelling of living system/environs complexes (e.g. the Lake Erie ecosystem) is one of the more promising ways to marshal decision support tools so the Parties may fulfill their agreement "to make a maximum effort to develop programs, practices and technology necessary for a better understanding of the Great Lakes Basin Ecosystem." The Lake Erie Task Force concluded that the most recent iteration of its model warranted a place in the suite of models of several logical types, such as graphic landscape models, word models, process-function models, mass balance models, community models, population models and watershed models, which must be interlinked in order to ascertain where understanding of the Lake Erie ecosystem is "robust" and where important gaps lie. However, integration of such models for enabling explorations of ecosystem integrity, type and scale, requires that there be a legitimate unified approach.

The Lake Erie Task Force accepted as fact that the ecospheric complex is fully interrelated, an unseamed whole in which everything is connected to everything else. The reason for doing ecological research is to find which connections are stronger and more significant, given certain criteria, than others. The goal in developing predictive models, such as LEEM, is not to show that everything is connected, but to show which minimal number of measurable connections may be used as a reasonable surrogate for the whole system, in this case Lake Erie. Models of any type are abstract and, hopefully, realistic. They are, however, models of reality and are not themselves reality.

5.4.2 Lessons

Through its work on LEEMP during the past two biennial cycles, the Task Force developed considerable insight regarding the effort to develop a comprehensive, ecosystem model for Lake Erie. Several key lessons learned are summarized below.

No one model can adequately address all the issues and problems associated with the dynamic Lake Erie ecosystem. By definition, ecosystems, such as Lake Erie, involve many complex, interactive processes and components that are in a constant state of change. Capturing all of these processes and components in any one model, while ensuring model outputs are realistic, certain and verifiable for users, is extremely challenging. In the Task Force's view, emphasis in the future should be placed on exploring ways of facilitating interface and possibly integration among complementary Lake Erie modelling initiatives. In fact, the ultimate Lake Erie ecosystem model may be a large comprehensive model capable of being the interface among numerous smaller models, each dealing with a specific component of the ecosystem.

The Lake Erie Task Force believes it successfully accomplished its goals. It developed an ecosystem model that has been deemed useful and will be used by the Lake Erie LaMP and the Lake Erie Committee of the Great Lakes Fishery Commission. The Task Force had an impact on the LaMP process, which now includes a modelling subcommittee. Furthermore, Dr. Koonce received additional funding from U.S. EPA to allow further model development. Therefore, the results of IJC efforts will not sit on the shelf -- they will be used -- and the Parties themselves are continuing the development and improvement of the work initiated by IJC.

The process by which a model is developed is at least as important as the technical capabilities of the model itself . From the outset of LEEMP, the Task Force pursued a collaborative, inclusive approach to model development. The Task Force believed that the constituency of over 60 Lake Erie modellers, researchers and managers, which had been actively involved in the model's development, testing and use, was one of LEEMP's greatest strengths and accomplishments.

Criteria for closure are essential to model design . All models are simplifications of real systems and are thus incorrect at some level of detail. Establishing criteria for closure provides a way of judging model adequacy. Nothing in the testing of the LEEM prototype indicated that it was inappropriate to address the range of problems for which it was designed. The initial problem focus included questions about the interaction of reductions in nutrient loading, invasion of zebra mussels, contaminants and fish management policies in causing the decline of important Lake Erie fisheries. However, review and testing of the prototype was not limited to those involved with its initial design. By opening the evaluation of the prototype to a wider audience, much was learned about model weaknesses and the implication of those weaknesses to use of the model for the intended purposes. At the same time, broader review resulted in new perspectives on problem definition for the model. It is important to recognize that model development is, and should be, an iterative process. Within this context, criteria for closure are needed for each iteration of a model to enable the model development process to move forward.

Strong project management is a prerequisite for success, particularly with multi-faceted projects spanning one or more years in duration. During its work, the Task Force met regularly to review progress, address and resolve issues and provide direction to its contractor/principal investigator. The Task Force also believed that its diverse mix of members -- with unique ideas, perspectives and areas of expertise -- also contributed to successful completion of work.

5.5 CONCLUSIONS

The Task Force, in its view, achieved both of its overall goals.

Model Modification and Improvement

By starting an iterative correction process for the Lake Erie Ecological Model, the prototype was further tested, developed and improved . This was accomplished through a series of interactive demonstrations, testing exercises and workshops, culminating in the development of a second iteration of the model (Figure 7). At this stage in its development, the model remains a prototype. Further evaluation and testing is needed to move from prototype to application of the model to the Lake Erie condition. It is important to note that even a fully evaluated and tested version will not be able to address all the ecological issues confronting management of Lake Erie. However, testing and evaluation of the prototype to date indicates that LEEM will have primarily heuristic value in addressing the range of problems for which it was originally designed -- to illustrate interactions among the key stresses affecting the Lake Erie ecosystem: the zebra mussel invasion, contaminant loading, the fisheries and declining nutrient loading.

Sustainable Model Development: Framework and Infrastructure

A strong foundation for future model development was developed by securing additional substantial funding for further model development. Dr. Koonce received a substantial U.S. EPA research grant to pursue further model development. In addition, in the Task Force's view, transfer of its experience in developing LEEMP to the Lake Erie LaMP has occurred through the involvement of LaMP participants in the process. Furthermore, the Lake Erie LaMP Work Group has created a modelling subcommittee that will use LEEM and other models. The Lake Erie Committee of the Great Lakes Fishery Commission will use the Eastern Basin version of LEEM to evaluate a variety of fishery, contaminant and nutrient issues.

Figure 7 Revised Structure, Lake Erie Ecological Model, 1996

Finally, in the Task Force's view, the LEEMP process made a substantial contribution to the use of models and modelling applications to enhance understanding and decision-making about Lake Erie. Key benefits and accomplishments include:

• active involvement of more than 60 Lake Erie managers, researchers and modellers in model development;
• information sharing regarding models, modelling applications and issues confronting Lake Erie; and
• development of a prototype that, with additional evaluation, testing and improvement, can be used and applied heuristically to assist:

  Managers - in exploring alternative management options, hypotheses and scenarios; clarifying issues and problems; and communicating and justifying management preferences; and

  Scientists - in screening hypotheses and identifying research priorities.

5.6 RECOMMENDATIONS

In hosting the initial model demonstration workshop in April 1995 and the Lake Erie Modelling Summit in September 1996, the Task Force observed the value of IJC's role in providing opportunities for information sharing and discussion among Lake Erie researchers, modellers and managers. Both meetings provided an excellent setting to exchange ideas, review progress and determine priorities for action.

IJC's Council of Great Lakes Research Managers is ideally suited and should, as an ongoing priority, serially explore various ecological avenues for enhanced interfacing and integration among complementary Lake Erie modelling efforts.

Therefore, the Lake Erie Task Force recommends the following.

• IJC mandate its Council of Great Lakes Research Managers to provide a regular forum for Lake Erie modellers, researchers and managers to share information, discuss progress and explore potential linkages among complementary Lake Erie modelling initiatives.

• testing multiple basin versions;
• experimenting to allow various habitat types to overlap within the model(s);
• exploring alternative representations of lower trophic levels; and
• determining the relationship between fish recruitment and habitat supply.

The Lake Erie Task Force recommends the following.

• IJC use ecosystem models in its evaluation of progress under the Agreement.

The LEEMP experience reinforces the view that management models can support such evaluation, but only if this provision of support is explicitly considered during model development.

1993-95 Priorities and Progress Under the Great Lakes Water Quality Agreement. International Joint Commission. Windsor, Ontario, August 1995. 184 pp.

IJC Task Force on Chemical Loadings of the Toxic Substances Committee. October 1988, "Report on Modeling the Loading-Concentration Relationship for Critical Pollutants in the Great Lakes." Report to the Great Lakes Water Quality Board. Windsor, Ontario. 275 pp.

Koonce, Joseph F. July 9-11, 1996. Report on Participation in Workshop on Impairment of the Beneficial Use of Fish Populations in Lake Erie. Simcoe, Ontario. Available from International Joint Commission. Windsor, Ontario. 2pp.

Koonce, Joseph F. and Locci, Ana B. March 31, 1995. Final Report on the Development of a Prototype Model for the Lake Erie Ecosystem. Available from International Joint Commission. Windsor, Ontario. 40 pp.

Koonce, Joseph F. and Locci, Ana B. March 15, 1996. Final Report on the LEEM Model Testing Workshop held on February 15-16, 1996. Available from International Joint Commission. Windsor, Ontario. 12 pp.

Koonce, Joseph F. and Locci, Ana B. March 29, 1996. Final Report on Phase II Development of the Lake Erie Ecological Model. Available from International Joint Commission. Windsor, Ontario. 31 pp.

LURA Group. June 13-14, 1994. Lake Erie Pre-Workshop, Lake Erie Steering Committee. Available from International Joint Commission. Windsor, Ontario. 16 pp.

LURA Group. March 31, 1995. Initiative I Report: Review of Existing Ecological Models. Available from International Joint Commission. Windsor, Ontario. 32 pp.

LURA Group. May 3, 1995. Lake Erie Prototype Model Workshop Summary Report. Available from International Joint Commission. Windsor, Ontario. 11 pp.

LURA Group. October 1996. Lake Erie Modelling Summit Report. Available from International Joint Commission. Windsor, Ontario. 15 pp.

LURA Group. November 1996. The Lake Erie Ecological Modelling Project - Final Report on 1995/1996 Priority. Available from International Joint Commission. Windsor, Ontario. 19 pp.

Minns, C.K., R.G. Randall, J.E. Moore and V.W. Cairns. 1996. A model simulating the impact of habitat supply limits on a population of northern pike, Esox lucius , in Hamilton Harbour, Lake Ontario. Can. J. Fish. Aquat. Sci. 53 (Suppl. 1).

5.8 MEMBERSHIP

Lake Erie Steering Committee

Mr. Douglas W. Alley Great Lakes Regional Office International Joint Commission 100 Ouellette Ave., 8th Floor Windsor, Ontario N9A 6T3	Mr. John F. McDonald Great Lakes Regional Office International Joint Commission 100 Ouellette Ave., 8th Floor Windsor, Ontario N9A 6T3
Dr. John M. Cooley Great Lakes Laboratory for Fisheries and Aquatic Sciences Department of Fisheries and Oceans P.O. Box 5050, 867 Lakeshore Road Burlington, Ontario L7R 4A6	Dr. Jeffrey M. Reutter, Director Ohio Sea Grant College Program The Ohio State University Research Center l3l4 Kinnear Road, Room 1541 Columbus, Ohio 43212
Dr. Douglas P. Dodge Fish & Wildlife Branch Ontario Ministry of Natural Resources P.O. Box 7000, 300 Water Street Peterborough, Ontario K9J 3C7	Mr. James D. Rozakis Assistant Regional Director Meadville Regional Office Pennsylvania Department of Environmental Resources 230 Chestnut Street Meadville, Pennsylvania 16335-3481
Dr. G. Douglas Haffner Great Lakes Institute Department of Biology University of Windsor Windsor, Ontario N9B 3P4	Dr. James W.S. Young SENES Consultants Limited l21 Granton Drive, Unit 12 Richmond Hill, Ontario L4B 3N4

Lake Erie Task Force

Mr. Douglas W. Alley Great Lakes Regional Office International Joint Commission 100 Ouellette Ave., 8th Floor Windsor, Ontario N9A 6T3	Dr. Douglas P. Dodge Fish & Wildlife Branch Ontario Ministry of Natural Resources P.O. Box 7000, 300 Water Street Peterborough, Ontario K9J 3C7
Mr. Edward A. Bailey Canadian Section International Joint Commission 100 Metcalfe Street, 18th Floor Ottawa, Ontario K1P 5M1	Dr. Jeffrey M. Reutter, Director Ohio Sea Grant College Program The Ohio State University Research Center l3l4 Kinnear Road, Room 1541 Columbus, Ohio 43212
Mr. Bruce L. Bandurski United States Section International Joint Commission 1250 23rd Street NW., Suite 100 Washington, D.C. 20440	Mr. James D. Rozakis Assistant Regional Director Meadville Regional Office Pennsylvania Department of Environmental Resources 230 Chestnut Street Meadville, Pennsylvania 16335-3481
Dr. Stephen B. Brandt Great Lakes Center for Environmental Research and Education SUNY College at Buffalo 1300 Elmwood Avenue Buffalo, New York 14222	Dr. Harvey Shear Regional Science Advisor Ontario Region Environment Canada 4905 Dufferin Street Downsview, Ontario M3H 5T4
Mr. Kelly Burch Meadville Regional Office Pennsylvania Department of Environmental Resources 230 Chestnut Street Meadville, Pennsylvania 16335-3481	Mr. Nelson Thomas U.S. Environmental Protection Agency Environmental Resources Laboratory - Duluth 6201 Congdon Blvd. Duluth, Minnesota 55804
Dr. John M. Cooley Great Lakes Laboratory for Fisheries and Aquatic Sciences Department of Fisheries and Oceans P.O. Box 5050, 867 Lakeshore Road Burlington, Ontario L7R 4A6	Dr. James W.S. Young SENES Consultants Limited l21 Granton Drive, Unit 12 Richmond Hill, Ontario L4B 3N4

Core Advisory Group

Dieter Busch, U.S. Fish & Wildlife Service

William Culligan, New York State Department of Environmental Conservation

David Dolan, International Joint Commission

Sandra George, Environment Canada

Del Graf, Pennsylvania Fish Commission

Ava Hottman, Ohio Environmental Protection Agency

Douglas Jester, Jr., Michigan Department of Natural Resources

Robert Lange, New York State Department of Environmental Conservation

Julie Letterhos, Ohio Environmental Protection Agency

Rob MacGregor, Ontario Ministry of Natural Resources

Francine Norling, U.S. Environmental Protection Agency, Region 5

Kenneth Paxton, Ohio Department of Natural Resources, Division of Wildlife

Philip Ryan, Ontario Ministry of Natural Resources

Craig Selby, Ontario Ministry of Natural Resources

Harvey Shear, Environment Canada

Ian Smith, Ontario Ministry of Environment & Energy

Additional Participants in Lake Erie Task Force Workshops and Consultations

Steven M. Bartell, SENES Oak Ridge Inc.

Keith Bedford, Ohio State University

Peter Boyer, International Joint Commission

Murray Charlton, Environment Canada

Murray Clamen, International Joint Commission

David A. Culver, Ohio State University

Joseph V. DePinto, University of Buffalo

David Dilks, LURA Group

Michael Gilbertson, International Joint Commission

Frank Gobas, Simon Fraser University

Lorne Greig, ESSA Technologies Ltd.

Ron Griffiths, Ontario Ministry of Environment & Energy

Andrew Hamilton, International Joint Commission

Reed Harris, Tetra Tech, Inc.

Robert J. Heath, Kent State University

Robert Hecki, Environment Canada

Ben Hobbs, Johns Hopkins University

Todd Howell, Ontario Ministry of Environment & Energy

Ora Johannsson, Department of Fisheries & Oceans

Kevin Kayle, Ohio Division of Wildlife

Roger Kenyon, Pennsylvania Fish & Boat Commission

Joseph F. Koonce, Case Western Reserve University

Roger L. Knight, Ohio Division of Wildlife

Betsy Kozuchowski, U.S. Fish & Wildlife

Ana Locci, Case Western Reserve University

Morgan L. McCosh, U.S. Fish & Wildlife Service

Ellen McDonald, Ohio State University

Scott Millard, Department of Fisheries & Oceans

Heather Morrison, Department of Fisheries & Oceans

Mohi Munawar, Department of Fisheries & Oceans

Kenneth M. Muth, Lake Erie Biological Station

James J. Nicita, University of Michigan

Sandra Parker, International Joint Commission

Henry Regier, University of Toronto

William Richardson, U.S. Environmental Protection Agency

Paul W. Rodgers, LTI-Limno-Tech, Inc.

David Schwab, NOAA, Great Lakes Environmental Research Lab

Francine Margaret Thielke, U.S. Environmental Protection Agency, Region 5

Stuart Whipple, University of Toronto

5.9 APPENDIX: CORE ADVISORY GROUP -- PRIORITY MANAGEMENT ISSUES

1. Changes in fish species composition (abundance) likely to occur with various combinations of fish management, nutrient loading and mussel effects. Fish species include walleye, yellow perch, ruffe, trout perch, white perch, white bass, emerald shiners, spottail shiners, lake herring, lake whitefish, smelt, gizzard shad, alewife, burbot, smallmouth bass, drum, sturgeon, round goby, coho salmon, chinook salmon, brown trout, lake trout, rainbow trout, sea lamprey.
   1. Can we sustain significant production and harvest of smelt with current mussel and phosphorus regimes?
   2. Is the current decline of walleye, yellow perch and smelt due to lower phosphorus loadings and mussel invasion?
   3. Would yellow perch and other species' harvest increase if phosphorus loads increase?
   4. What would be the effect of reducing the predation effects of walleye and lake trout on smelt and yellow perch harvest?
   5. What, if any, is the interaction between sustainable harvest of yellow perch and sustainable harvest of walleye?
   6. What is the impact of ruffe invasion on yellow perch and young-of-year classes of walleye?
   7. What is the impact of reduced sea lamprey controls on salmonids, coregonine, burbot and smelt?
2. Changes in contaminant body burdens with same factors (as in #I) as well as changes in contaminant loadings (PCB, DDT, mercury and atrazine).
   1. Should changes in body burdens be expected as a result of decreased phosphorus?
   2. Latency of response of body burdens to changes in phosphorus or mussels? (complete list of species, as relevant)
   3. Do concentrations of contaminants in various species show consistent ratios or divergent ratios?
3. Current mussel biomass status and effect of nutrient loading on mussel biomass.
   1. Do mussels increase primary production?
   2. What are the net effects of mussels on primary, secondary and benthic production and latency of those interactions?
   3. What are the consequences of system changing from pelagic to benthic as a result of mussels?
4. Interaction of community structure changes including vegetation, fish populations, nutrient loading (including silica) and water quality.
   1. What are the impacts of atrazine on food web, energy transfer changes in vegetation, plankton, and algae?
   2. What are the effects of silica or other secondary nutrient limitations on food web dynamics and fish community structure? (edible/inedible - spatial distribution of productivity)
   3. What is the effect of fish harvest on water quality parameters of specific interest?
   4. What is relationship between walleye abundance and distribution with water quality (transparency)?