Lakeshore Habitat Condition in Wisconsin. Katie Hein, Caitlin Carlson, Paul Garrison & Tim Asplund

Transcription

1 Lakeshore Habitat Condition in Wisconsin Katie Hein, Caitlin Carlson, Paul Garrison & Tim Asplund

2 When you look at a lake, what do you see?

3 Limnology focused on the pelagic zone and so did state wide monitoring efforts Secchi depth Phosphorus Chlorophyll-a Temperature Dissolved oxygen

4

5

6 Littoral zone often more productive and diverse than pelagic! Riparian Littoral Pelagic

7 Littoral Habitat Destruction: Leading Threat to Lake Health John Picken Keith Pheanix Gretchen Hansen

8 Frogs per Mile Green Frogs y = x x R² = Homes per Mile Woodford and Meyer 2002

9 Treefalls Per Mile Treefalls y = ln(x) R² = Homes Per Mile Christensen et al. 1996

10 We understand impacts What can be done?

11 Goals Initiating Lakeshore Habitat Monitoring in Wisconsin Statewide inventory of lakeshore health Identify problem areas for restoration Evaluate shoreland habitat restorations

12 Evaluate Success of Habitat Restorations BEFORE Bony Lake The Johnsons Pamela Toshner AFTER Pamela Toshner

13 Goals Initiating Lakeshore Habitat Monitoring in Wisconsin Statewide inventory of lakeshore health Identify problem areas for restoration Evaluate shoreland habitat restorations

14 What percentage of lakes are in good, fair, or poor condition? EPA National Lakes Assessment 5 year cycle Benthic Macroinvertebrates Algal Toxins Chlorophyll A Nutrients Phytoplankton Sediment Dating Sediment Diatoms Sediment Mercury Water Chemistry Zooplankton Shoreline Habitat 904 sites

15 Lake Sampling Design Riparian Littoral Littoral 15 m

16 Shoreline Habitat Variables 5 Categories: Absent Sparse Moderate Heavy Very Heavy Littoral Zone Bottom substrate silt, sand, gravel, cobble, boulders, bedrock, wood, detritus Macrophytes submergent, emergent, floating, total cover Fish Cover herbaceous veg., big wood, small wood, inundated live trees, overhanging veg, ledges, boulders, docks 0% <10% 10-40% 40-75% >75% Riparian Zone Canopy > 5m high big trees, small trees Understory woody shrubs, herbaceous plants Ground Cover 0.5 5m woody shrubs, herbaceous plants, inundated veg, barren Shoreline Substrate silt, sand, gravel, cobble, boulders, bedrock, wood, detritus Human Influence buildings, commercial, park facilities, docks/boats, walls, trash, roads/railroad, power lines, row crops, pasture, orchard, lawn

17

18

19 3 Metrics to Assess Health Human Influence Riparian Habitat Littoral Habitat Average Count of Human Influences Kaufmann et al Lake & Res. Mgmt. Average % Cover Woody Vegetation & Inundated Vegetation Average % Cover Emergent & Floating Macrophytes & Most Fish Cover

20 Metrics are Specific to Combined Ecoregions Upper Midwest Temperate Plains

21 Lake Shoreline Habitat Sampling 32 lakes in lakes in lakes in 2013

22 Proportion of Lakes Sampled Lakeshore Habitat Condition National Average Riparian Littoral Rip-Lit Human Good Fair Poor

23 Lakeshore Habitat Health Riparian Littoral Human Influence Good Fair Poor Forest Agriculture

24 Metric Validation ALL METRICS = GOOD ALL METRICS = POOR Rice Lake Wallace Lake 100-m Riparian Buffer 84% Wetland 16% Forest 100-m Riparian Buffer 28% Urban 62% Grassland 3% Wetland 7% Forest

25 Littoral Metric Riparian Metric Human Disturbance Metric How do metrics relate to land use? % Urban in 100 m buffer Poor Fair Good % Urban in 100 m buffer % Urban in 100 m buffer

26 Which aspects of shoreland habitat are most influenced by development? Reference Non-reference Forest Agriculture

27 Which parameters differ between reference and non-reference lakes? Reference Non- Reference Big Trees 13% 22% Understory non-woody Groundcover non-woody Groundcover bare 44% 29% 9% 20% 1% 5% No Effect: Small trees Understory woody Groundcover woody Groundcover inundated

28 Conclusions Most lakes in Wisconsin are in good health in terms of riparian and littoral habitat despite most lakes being fair in terms of human development On the ground measurements needed! Non-woody understory vegetation most negatively affected by development

29 Next Steps Analyze relationships of habitat indicators to lake size, riparian land use, and other variables Develop Wisconsin-specific habitat metrics Test precision of metrics Initiate statewide lakeshore habitat monitoring