Wisconsin Trout and Climate Change: Predictions and Strategies Duke Welter TU Western Great Lakes Conservation Coordinator Midwest Regional Meeting March 28, 2015
Outline Quickie Tour of Wisconsin Trout Resources Statewide summary of projected impacts Driftless Summary Mitigation Techniques
10,500 miles Of trout water Generally 4 types
Northern Highlands Basaltic Bedrock Snowmelt source from lakes and welands Relatively Infertile * Thermally Sensitive Drought Sensitive
Central Sands Groundwater fed Glacial gravels & boulders ( Drift ) Relatively fertile --Mecan River
Anadromous Great Lakes Fisheries Flow to Lakes Michigan and Superior Lake run steelhead, browns, coho & Coaster brook trout * Resident Brooks & Browns
Driftless Spring Creeks Spring-fed Very Fertile Thermally buffered 2,500 miles in WI Driftless Browns and Brooks --Lost Creek (really)
Climate forecasts predict a much different Wisconsin By 2030: our summers will resemble current Illinois temperatures By 2095: our summers will resemble current Arkansas temperatures and our winters will resemble current Iowa temperatures
Thermal Resilience of Trout Streams Stream Length (miles) 200 150 100 50 0 200 150 100 50 Cold (future) Cold-transition (future) Warm-transition (future) Warm (future) FUTURE 2046-2065 CURRENT 0 Watershed Name
Optimum Temps: 55-63 F.
Future Challenges Resilience of Brook Trout to Climate Warming limate Effects on Brook Trout Distribution (2046-2057) Total Stream Length (miles) 900 800 700 600 500 400 300 200 100 Stable Brook Trout Risk Brook Trout Lost Brook Trout 0 Baraboo River Region Black River Region Chippewa River Region Kickapoo River Region Lower Wis River Region Kinnikinnic River Region Platte River Region Pecatonica River Region Planning Regions of the Driftless Area
Optimum Temps: 58-68 F.
The image part with relationship ID rid3 was not found in the file. Future Challenges Resilience of Brown Trout to Climate Warming limate Effects on Brown Trout Distribution (2046-2057) Total Stream Length (miles) 1,500 1,000 500 Stable Brown Trout Risk Brown Trout Lost Brown Trout 0 Baraboo River Region Black River Region Chippewa River Region Kickapoo River Region Lower Wis River Region Kinnikinnic River Region Platte River Region Pecatonica River Region Planning Regions of the Driftless Area
Future Challenges Climate Change Total Stream Length (miles) Climate Effects on Smallmouth Bass Distribution (2046-2057) 500 400 300 200 100 Smallmouth Bass - Currently Present Smallmouth Bass - Gain Smallmouth Bass - Possible Gain 0 Baraboo River Region Black River Region Chippewa River Region Kickapoo River Region Lower Wis River Region Kinnikinnic River Region Platte River Region Pecatonica River Region Planning Regions of the Driftless Area
Results of Stressors Alters brook and brown trout competition or interactions Streams may convert from trout to non-trout (e.g. Smallmouth bass) waters Susceptibility to other challenges (e.g., gill lice)
Opportunities for TU If groundwater is the key, and habitat and land use are primary tools, consider how chapters and councils might build: Advocacy programs for groundwater protection Strong project capacity Perhaps Farm Bill Fish Biologists to bring fishfriendly land use aid to farmers Triage: not only streams, but concentration of TU resources where we get the best bang for the buck
QUESTIONS?
The image part with relationship ID rid4 was not found in the file.
Future Challenges Climate Change Trout are very sensitive to changes in temperatures: Climate models project warmer air and water temperatures by mid-century (2046-2065) Smallmouth bass are projected to expand their range Brook trout need cold temperatures to survive. There may be as much as a 75% decrease in the number of brook trout stream miles in the future. Brown trout are more tolerant than brook trout to warmer water. Brown trout will see modest reductions in their future distribution. Projected increases in stream temperature vary across the Driftless Area, primarily due to differences in groundwater inputs. Some of the larger waters that currently support trout may support smallmouth bass in the future. None of the waters where smallmouth bass currently exist are projected to warm enough to affect the fishery.
Timber Coulee Creek Habitat Restoration 1985 Before After