Marissa received her Ph.D. from the University of Missouri where she studied the habitat features used by grasshopper and Baird’s sparrows to choose their breeding territories in North Dakota and Saskatchewan, Canada. She completed a post-doctoral project with the Smithsonian Institution and the University of Missouri, assessing community-based conservation options for African savanna elephants. She joined The Nature Conservancy as lead Prairie Ecologist for Minnesota, North Dakota and South Dakota in January 2010. Marissa is also an adjunct faculty member in the Biology Department at the University of North Dakota.
What does a day in the life of a prairie ecologist look like?
To start with, I get to spend time in tallgrass and mixed-grass prairies in some of the most spectacular grassland landscapes in the Great Plains including Tallgrass Aspen Parkland in Minnesota, the Missouri Coteau in North Dakota, Conata Basin in South Dakota and the Prairie Coteau in all three states.
I help with ecological monitoring of the sites for planning and management, and I conduct research to guide those plans. Prairie restoration is also necessary in many areas, and there is much to learn about prairie restoration. For example, how do sites change over time after their initial plantings, and how do you keep invasive, non-native plants out of those sites?
What do you like about prairies?
I like the open spaces, the feeling I get when I am on a prairie that nature could go on forever. Grasslands are beautiful, and it's a subtle beauty—you have to look closely to see the small flowers and butterflies that may be close to the ground and inconspicuous.
As a result, many people don't appreciate grasslands – it’s an underdog ecosystem. I guess I like grasslands for the same reason I like the Chicago Cubs and the Kansas City Royals. I like to root for the underdogs—I guess that comes from growing up near Kansas City.
You've done interesting research in grasslands. Tell us more about your work with birds.
For my doctorate, I studied the habitat features used by grasshopper and Baird's sparrows to choose their breeding territories in North Dakota and Saskatchewan, Canada. These are related species that vary in their habitat requirements; Baird's sparrows are specialists and grasshopper sparrows are generalists. So, combined, they hopefully represent a range of behaviors by sparrows that occur in grasslands.
Grassland birds are declining more rapidly than other groups of songbirds, despite habitat restoration and conservation efforts. We need to understand their needs, such as what they look for when deciding where to nest, to better conserve them.
What are the emerging challenges confronting our grasslands?
Grasslands are the most endangered and least protected ecosystems in the United States and the world.
Many have been converted to farmland. Emerging challenges to grasslands include green technologies and climate change. Green technologies offer both threats and opportunities – the challenge is in learning how to adopt them in ways that do not place grasslands at risk. Wind farms, for example, need to be sited carefully. Biofuel crops, especially cultivated crops, can reduce the incentive for landowners to keep their land in grass and result in more fragmented habitats.
The impact of climate change is uncertain. Grasslands have great variability and so are adaptable ecosystems, but we do not know if the climate changes that are projected will fall within their ability to respond or push them beyond their limits.
How are you and others at the Conservancy working to address some of these challenges?
I recently finished a grassland bird project in North Dakota looking at the effect of grazing intensity on grassland birds. We found that light-to-moderate grazing generally had a positive impact on the abundance of grasshopper sparrows, a species whose population is declining, and didn’t negatively affect other birds. These kinds of studies are helpful to the Conservancy and its partners in guiding and, when necessary, changing how we manage our land.
I have an ongoing research project in conjunction with the U.S. Fish & Wildlife Service and the Minnesota Department of Natural Resources to look at how grazing and burning are impacting our native plant communities and what is most effective for reducing invasive species.
I worked with Joe Fargione, the Conservancy’s science director in North America, to develop a methodology for calculating how much carbon dioxide you can keep from being released into the air when you protect grasslands from being converted to row crops like corn, which is happening rapidly now in parts of North and South Dakota. Once we calculate this number for a specific area, the “carbon credits” can be sold on the voluntary market to utilities and other companies to offset the emissions from their operations, and the revenue from these sales can be used to protect additional acres of native grassland.
And you've also studied elephants. What’s the connection there with prairies?
That was my post-doctoral research both at the University of Missouri and with the Smithsonian Institution. I looked at the dynamics of elephant populations in East Africa outside protected areas—what parks they may have come from, the genetic relationships with other individuals in their groups and their ability to adapt to life adjacent to croplands and alongside cattle.
The goal is to eventually create a regional plan for elephant conservation using land management. Elephants are a keystone species in savanna grasslands that are not unlike the mixed-grass prairies in North Dakota and South Dakota.
These are ecosystems where productivity is patchy and the community must work together to sustainably use these resources. The Maasai have been able to share their grazing areas with each other and with elephants, and that's a model that could be useful here (communal grazing alongside wildlife). Some U.S. ranchers have already visited Maasai communities to observe their methods.