By Patrick Lyons
Researchers are mapping the greatest sources of stress on the Great Lakes to better target where and how restoration funds are spent.
The Great Lakes Environmental Assessment and Mapping Project is the most comprehensive look at the status of the lakes to date, said Peter McIntyre, an assistant professor at the University of Wisconsin and a senior author of the study.
Scientists led by researchers at the University of Michigan and University of Wisconsin-Madison report this week in the Proceedings of the National Academy of Sciences that they gathered information on 34 Great Lakes environmental challenges. They included such things as polluted runoff, invasive species and habitat destruction.
“Government agencies and citizen groups have done a great job of collecting information about different kind of stressors,” McIntyre said. “But they usually do it for just one stressor or just one lake and this information has never been pulled together for the whole basin and across all the different stressor types.”
The researchers asked scientific and policy experts to assess the relative impact of different stressors to one another in particular areas of the basin. They plotted that information as data layers on the map.
Researchers also took into account the services that people receive from the lake, including beaches, fisheries, marinas and bird watching spots.
“We mapped those out and compared the distribution of ecosystem service sites to the threat map,” McIntyre said. “The places we want to worry about the most might be a place where we can see very high ecosystem threat levels that coincide with a major public swimming beach, marina or area where bird watchers like to go.”
Visualizing where the threats and benefits overlap helps us be more strategic in our restoration efforts, said Patrick Doran, director of conservation for The Nature Conservancy, in Lansing, Mich.
“I think this map will allow us to be extremely targeted and clear on which stress we are attempting to abate and what are potential outcomes and responses from that,” said Doran, who worked on the project. “What do people care about and value? That is as important a part of the equation as where the threats are located.”
The goal is to make restoration priorities based on community priorities, McIntyre said.
“If what you care about is bird watching areas and you want to do a restoration project to enhance a place that is recognized as an important bird watching area, our comparison of the threat map to the bird watching areas allows the community to identify and create their own response based on the level of threat they want to alleviate,” he said.
The researchers found that areas of high contamination were also the areas that provided the largest amount of services to people, meaning the places that people value the most are also most at risk.
Often restoration efforts focus on one stressor at a time, but this study provides a more comprehensive level of data, McIntyre said.
That makes restoration more effective by taking into account every stressor in play in a particular ecosystem, Doran said.
“The Nature Conservancy is active in western Lake Erie on wetland restoration,” Doran said. “We might be able to rehabilitate a lot of the degraded habitat, but we might not see a response in fish or wildlife until we start to address some of the others stressors like contaminated sediments or aquatic invasive species.”
The map could be used as a tool when making decisions about where to funnel restoration funding such as the Great Lakes Restoration Initiative. That federal program began in 2009 and entails proposed expenditures of $5 billion over 10 years.
“We are big believers in the Great Lakes Restoration Initiative and we are trying to provide a new resource that would allow, in the next round of funding, decisions that would allow strategic selection of sites based on the entire assembled set of threats and also focused on the locations where people are directly using the Great Lakes,” McIntyre said.
So far the initiative’s projects appear in line with the map.
“We have explicitly analyzed the sites where the GLRI money has been spent over the last 4 years and that initiative was very successful at identifying sites that have high cumulative stress and making good investments in alleviating particular types of threats,” McIntyre said. “Our purpose was to complement what has already been done and we demonstrated incidentally that the GLRI selection of sites for the last four years really matches well with the current threat map for high threat areas.”
The map may help guide the initiative at current restoration sites as well as target future projects.
“What our study adds to that effort is it clarifies sites where the GLRI is addressing one or a handful of stressors where our maps indicate other stressors are affecting those sites,” he said. “Those could be additional priorities for restoration at the same places, or you can use our maps to identify additional sites that would be good sites for future restoration efforts.”
The opportunity for strategic restoration projects in lower threat areas is another benefit of the project.
“Often places that may seem to not be in deep trouble because there are no acute symptoms are facing a broad suite of threats that are affecting the ecological health of the system even though we haven’t perceived it yet,” McIntyre said.
Many restoration projects begin on an “emergency basis” in response to particularly high levels of contamination and stressors, McIntyre said. Working in areas with lower threat levels could be a preemptive measure to keep them from ever reaching emergency levels of degradation.
The project also helps gauge progress.
“We have a baseline now, and this project went out and grabbed 34 data layers,” Doran said. “We could re-do this map in 10 years, use this map to evaluate change over time.”
The study was initiated at the University of Michigan and supported by the Fred A. and Barbara M. Erb Family Foundation. Additional funding was provided by the Nature Conservancy’s Great Lakes Fund for Partnership in Conservation and Economics and the University of Wisconsin-Madison.