Resilient Habitat for Heritage Brook Trout

Word has spread that Southeast Minnesota's streams support a robust trout fishery and trout fishing now generates $800 Million annually to local communities. Less well known is that a small number of these streams hold remnant populations of native brook trout unique to Southeast Minnesota. They have persisted for thousands of years and through the time of European settlement. These ?Heritage Brook Trout? populations are indigenous to this unique area and a Species in Greatest Conservation Need. Yet their long-term persistence is far from secured.

Small populations of Heritage Brook Trout persist in perhaps 20% of Southeast trout streams, and are abundant in just 17 streams. These face growing challenges from land conversion, parcelization, intensified agricultural practices, poor land management and an increasingly wet and warm climate. Recent DNR research suggests that consistent baseflow from groundwater springs can provide a level of resilience to these coldwater systems. Coldwater streams with ample spring baseflow may provide a climate refugia for brook trout and other coldwater species.

Minnesota Trout Unlimited and DNR Fisheries have made significant investments in restoration and enhancement of in-stream habitat in Southeast Minnesota. Protecting the health of the surrounding watersheds will be critical to maintaining these coldwater streams and gaining the maximum benefit from in-stream improvements. Improved riparian habitat and connectivity are key factors in stream quality; they also provide important corridors for terrestrial wildlife, connecting large habitat cores.

Program partners Minnesota Trout Unlimited, Minnesota Land Trust, The Nature Conservancy, and Trust for Public Land used several resilience factors to identify six subwaterhseds where conservation of robust populations of Heritage Brook Trout is most achievable: Beaver Creek, East Indian Creek, Rush Creek-Pine Creek, South Fork Root River, Zumbro Tributaries, and Whitewater River. Partners will harness their collective expertise in land protection and terrestrial and in-stream habitat restoration/enhancement to increase the resiliency of these coldwater systems and their Heritage Brook Trout.

While restoring in-stream habitat has improved stream bank and aquatic habitat in many coldwater reaches, little work has been done restoring broader floodplain areas surrounding DNR easement corridors. Restoring floodplain forests, wet prairies and wetlands provides significant benefits to stream health and corridors provide habitat connectivity.

Because of the Driftless Area's rugged terrain, the vast majority of its natural communities occupy steep slopes that play an important role in the region's hydrology. Protecting through targeted fee and easement acquisition and improving the condition of these forests and prairies through restoration and enhancement will improve their ability to slow runoff and increase infiltration. This will reduce sediment and nutrient delivery to streams and improve the hydrology of the watershed by reducing peak flows and increasing baseflows, while also improving plant diversity and habitat for wildlife in one of the most biologically diverse parts of Minnesota. Restoring habitat along the upper edges of steep forested slopes will help buffer the natural communities, while significantly slowing the formation and spread of gullies that deliver large amounts of sediment and nutrient runoff directly to streams.