A new study by Nature Conservancy scientists identifies and rates areas across the Great Lakes and Tallgrass Prairie region that are most likely to harbor a diversity of plant and animal species despite a warming climate that will threaten some species and cause many organisms to shift across the landscape in unpredictable ways.
"Resilient Sites for Terrestrial Conservation in the Great Lakes and Tallgrass Prairie Region," the first study of its kind in the Midwest and part of Canada, will provide an invaluable road map for protecting biodiversity in an uncertain future.
"We don't know what’s going to happen to many native species, but this study shows us where they will have a better chance to survive and persist in the future," says Conservancy climate change ecologist Kim Hall, one of several authors of the three-year project.
The Conservancy report covers all of Minnesota, Wisconsin, Michigan, and Iowa, and parts of North Dakota, South Dakota, Nebraska, Kansas, Missouri, Illinois, Indiana, Ohio, Pennsylvania, New York, Ontario, and Manitoba.
Conservation efforts have long sought to protect areas that support high numbers of native species, many of which may be endangered by changes in land use and shrinking habitat.
The problem is that climate change will likely cause plants and animals to shift their locations across the map.
Are there any guarantees that the protected areas of today will support the same species 100 years from now?
Average annual temperature in the Great Lakes and tallgrass prairie region is estimated to increase 3 to 12 degrees F by the end of the century. Estimates of precipitation range from 17 percent drier to 30 wetter with a good chance of more intense storms. Given that range of uncertainty, it's difficult to anticipate how individual species will respond. Predicting how entire plant and animal communities will change is even more challenging.
To predict which sites will be important for species in the future, Conservancy ecologists examined different topographies, geologies and elevation ranges that support species diversity.
A prairie that rolls off a hilltop, down a gentle slope to a wet spot at the base of a hill typically supports more species than a level patch of grass because it encompasses different soils, various water runoff patterns, and varied exposures to drying winds, drenching rains, and warming sunlight.
By examining 336 million acres down to the scale of 30-meter square plots, areas about twice the size of a small city lot, the scientists were able to identify landscape features that create "microclimates" that support the greatest variety of plants and animals in an area.
These features will endure despite a changing climate. They tend to support the greatest species diversity today and are likely to or are expected to support the greatest diversity in the future, even though the specific species found in those areas may change over time. Such places offer "resilience"—the ability of diverse number of species to persist and recover in a changing climate.
Meredith Cornett, the Conservancy's director of conservation science in Minnesota, North Dakota and South Dakota and a co-author of the recent report, calls these resilient sites "natural strongholds," that through their variety will provide niches and refuges for threatened species that the surrounding landscape may lack.
Another feature of resilience is connectivity. A 40-acre prairie surrounded by crop fields and highways is isolated. "There’s nowhere for those species to go," says Cornett. But connecting a small patch to other prairie remnants or wetlands increases its resilience. "There are these great levers we can pull to help species persist/survive. One of those is to help restore connectivity in places where it’s been disrupted," she says.
Conservancy scientists anticipate their study will be invaluable to federal, state, local and nongovernmental organizations involved in land management and protection.
"We’ve been really encouraged by the level of interest," says Cornett. "We view this as something that can guide future investments in conservation and in restoration and management."
Several government scientists who have reviewed the study agree. "The report will give the Minnesota Department of Natural Resources a great tool for evaluating the relative resilience of sites to climate change. Added to the biodiversity data we have already collected for the state, we'll be much better prepared to make smarter land protection and management decisions," says Hannah Texler, plant survey supervisor for the Minnesota DNR.
Anyone who is interested in ensuring that large natural areas remain diverse and resilient can contact their state and local conservation agencies and land trusts to make sure they’re aware of the report and its potential to guide protection efforts.
Mark Anderson, a Conservancy scientist who has helped lead the natural strongholds studies, said the study’s findings should be used in combination with more detailed data and field validation from various sites. "This analysis doesn’t make decisions, instead, it provides estimates of resilience that should be integrated and interpreted with additional data to inform conservation decisions."
The resilient sites project was supported by Conservancy members and a grant from the Doris Duke Charitable Foundation.
"We are excited about the new chapter of this cutting-edge research by The Nature Conservancy," said Sacha Spector, program director for the environment at the Doris Duke Charitable Foundation. "In an era of accelerating climate change and scarce dollars for land conservation, this work is critical because it shows us the most important places we need to protect for nature and people."
Learn additional information about the study, including an overview, link to download the report, data and a mapping tool.