Climate Change and Dams Present Challenges for Wild Rice at Rainy Lake

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Kevin Bunch
August 21, 2018
canoe and bed of wild rice in minnesota

 

A bed of wild rice in Kathio State Park in Minnesota, grows in the water. Credit: Brett Whaley
A bed of wild rice in Kathio State Park in Minnesota, grows in the water. Credit: Brett Whaley

Wild rice has been struggling in historically fertile ground at Rainy Lake, located at the Ontario-Minnesota border. While climate change has played a role in the declining success of the notoriously sensitive plant, water level and flow management by humans has played a part, too.

The damming and water management regime of Rainy Lake and its water system over the decades has been a major contributing factor to the decline of wild rice, or manoomin (as it’s known in Ojibwe), with successful harvests only occurring twice over the past 13 years, according to Allan Yerxa, lands and resources coordinator for the Couchiching First Nation.

Rainy Lake is linked to Namakan Lake, and further downstream, Lake of the Woods. Water levels on the lakes are managed through a series of dams. Operators are required to try and keep water levels within a band known as the rule curves, with oversight by the IJC’s Rainy-Lake of the Woods Watershed Board.

Rainy Lake is located in the middle of a water basin that runs between the state of Minnesota and the province of Ontario, with the Couchiching First Nation on the western shore of the lake. Credit: IJC
Rainy Lake is located in the middle of a water basin that runs between the state of Minnesota and the province of Ontario, with the Couchiching First Nation on the western shore of the lake. Credit: IJC

In part, problems facing wild rice by water level and flow management have been the result of invasive hybrid cattails taking advantage of the regulated and consistent water levels. The cattails thrive in the same habitat as wild rice, and grow in thick mats, pushing out native plants as they outcompete them. Muskrats are a major natural control source for the cattails, but were rarely surviving the winter due to water levels being drawn down over the winter months under rule curves put in place in 2000. Yerxa said there also have been issues with fluctuating water levels during growing and harvesting seasons, causing the plants to fail.

“One hundred years ago, the wild rice we harvested was a food staple and something that was just part of your diet, and we’d pick enough to last a year,” Yerxa said. “Nowadays it’s almost a luxury to have wild rice in your cupboard – that’s how it’s affected the First Nations people.”

With so little to harvest, Yerxa said his community usually buys wild rice from other First Nations further north for fall workshops and cultural activities. And there’s no realistic way to expand habitat for wild rice plants in the area so that they can grow independent of the Rainy Lake system, he said, as is the case for other indigenous communities to the north and south.

The IJC has been interested in improving conditions for wild rice in the Rainy Lake water system. Over the past several years, the IJC has been working with regional First Nations, funding studies about wild rice in the Rainy-Namakan basin (along with other issues important to their communities).

Peter Lee, a wetland ecology specialist with Lakehead University in Thunder Bay, Ontario, said wild rice harvests on Rainy Lake vary year-to-year, sometimes dramatically. For example, in 2014 there was no appreciable harvest due to high water levels, but 2015 and 2016 were more successful. Nevertheless, there has been a long-term drop.

 “Harvests of wild rice in Ontario have declined over 150,000 pounds on Rainy Lake, and over 1 million pounds on Lake of the Woods since the 1970s, to less than 100,000 pounds in total,” Lee said. That is largely due to water level increases, though there have been economic factors as well.

Lee has worked with the Seine River First Nation using IJC funding to determine the best water conditions for rice growth.  By using floating rafts, they were able to determine ideal water depth and timing for wild rice stands, concluding that the submerged stage and “floating leaf” stages are the most sensitive periods.

A later study done by the Seine River First Nation and Lee looked at the severity of impacts of the hybrid cattail, discovering that hundreds of hectares of wild rice stands had been taken over. This research also found that by cutting the cattails beneath the water surface – such as by using an airboat – the invasive plants would be killed, and any wild rice seeds still in the bed would germinate and regrow.

Additional adjustments to how water levels are managed on Rainy Lake also are expected to help. New rule curves went into effect Aug. 1, with one of the goals being improving wild rice survival and harvest rates.

One of the adjustments made changes to when the lakes are drawn down, reducing the winter drawdown period substantially. While the overall drawdown amount is similar, this should help more muskrats to survive the winter months, building shelters closer to open water, which should in turn help control the invasive cattail problem and provide more space for wild rice to plant itself.

The watershed board’s Water Levels Committee has issued new operational guidelines for dam operators. While the new rule curves provide leeway to target specific water levels and flows within the rule curve bands for particular needs or goals – provided weather and water conditions allow for it – the guidelines provide seasonal considerations and best practices. These operational guidelines will be open for public comment soon, and are expected to continue to be amended as new information and circumstances arise.

As an added layer of support for wild rice survival, the new rule curves allow for water levels to be maintained for wild rice growth and harvest if weather and water conditions permit.

Yerxa said the Couchiching First Nation, along with the other First Nations that are part of Treaty No. 3, are working with the board and watershed committee on a written wild rice protocol detailing ideal water levels, flows and timelines for wild rice growth. They hope to make this protocol available to the Rainy-Lake of the Woods Watershed Board and IJC to assist with water management efforts.

More difficult to plan for is climate change. Yerxa said his community has been seeing more frequent and severe storms. These storms can knock the plants over, or knock rice grains off the plants before they can be harvested.

Besides bringing flood risks to communities, these storms can increase nutrient runoff, which leads to more turbid water that hinders germination and plant development, according to Peter David, wildlife biologist with the Great Lakes Indian Fish and Wildlife Commission.  And floods during the floating leaf stage can cause dramatic losses including from a fungal disease known as brown spot.

Additionally, wild rice is adapted for harsh climates in cold, northern latitudes, David said. Shorter and warmer winters extend the growing season, leading to wild rice being readily outperformed by species adapted to warmer conditions.

Regardless of these challenges, Yerxa said the Couchiching First Nation will continue to hold onto a bag of wild rice to reseed its habitat on Rainy Lake each spring, and hope that it’ll take hold and grow.

A harvesting machine moves to remove the invasive hybrid cattail plants in Voyageurs National Park August 2017. Credit: IJC
A harvesting machine moves to remove the invasive hybrid cattail plants in Voyageurs National Park August 2017. Credit: IJC


 

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Kevin Bunch

Kevin Bunch is a writer-communications specialist at the IJC’s US Section office in Washington, D.C.