Sensitive Ecosystems of the Atlin-Taku Planning Area Adrian de Groot, MSc, RPBio Jim Pojar, PhD, RPBio Contact: Adrian de Groot Drosera Ecological Consulting 8612 Horlings Rd, Smithers, BC, V0J 2N2 E-mail: [email protected] Tel: 250-877-7737 Prepared for: Bulkley Valley Centre for Natural Resources Research & Management Smithers, B.C. Prepared: February 2009 Table of Contents Table of Contents........................................................................................................... 2 List of Figures ............................................................................................................... 4 List of Tables................................................................................................................. 5 Executive Summary ....................................................................................................... 6 Acknowledgements ........................................................................................................ 8 1.0 Introduction ....................................................................................................... 9 2.0 Study Area Description .......................................................................................10 2.1 Biogeoclimatic Classification in the Study Area....................................................10 3.0 Methods ...........................................................................................................13 4.0 Results .............................................................................................................15 4.1 CDC List of At-Risk Ecological Communities........................................................15 4.2 Sensitive Ecosystems grouped by Biophysical Site Type .......................................16 4.2.1 Grasslands-Shrub/Steppe...........................................................................17 4.2.2 Dry Forests/Pine-Lichen Flats......................................................................20 4.2.3 Floodplains...............................................................................................20 4.2.3.1 Lower Taku River and Tulsequah River ...................................................21 4.2.3.2 Sheslay and Inklin Rivers......................................................................23 4.2.3.3 O’Donnell River ...................................................................................24 4.2.4 Limestone Bedrock Influenced Communities..................................................25 4.2.4.1 Calcareous wetlands ............................................................................25 4.2.4.2 Tufa ..................................................................................................27 4.2.4.3 Canyons.............................................................................................28 4.2.4.4 Alpine................................................................................................30 4.2.5 Ultramafic Bedrock....................................................................................31 4.2.6 Hydromagnesite Deposits...........................................................................33 4.2.7 Wetlands .................................................................................................34 4.2.8 Water Features.........................................................................................34 4.2.9 Warm Springs ..........................................................................................36 4.2.10 Jökulhlaups/Glacial Outburst Floods .............................................................36 4.2.11 Waterfalls ................................................................................................37 4.2.12 Volcanics .................................................................................................38 4.2.13 Landslides................................................................................................39 4.2.14 Glaciofluvial Landforms ..............................................................................40 4.2.15 Permafrost Features ..................................................................................40 4.2.16 Coastal - Boreal Transition .........................................................................40 4.2.17 Rock Glaciers ...........................................................................................41 4.2.18 Alpine .....................................................................................................41 4.2.19 Lichen Landscape......................................................................................42 4.2.20 Canyons ..................................................................................................43 4.2.21 Other ......................................................................................................43 4.3 Rare Ecosystems Identified by Conservation Area Design ....................................45 4.4 Plant Species of Interest Found During Fieldwork ...............................................47 5.0 Threats to Sensitive Ecosystems ..........................................................................49 5.1 Methods for Ranking Threats............................................................................49 5.2 Types of Threats to Sensitive Ecosystems ..........................................................51 Bulkley Valley Centre for Natural Resources Research & Management 2 5.3 Ranks of Threats ............................................................................................52 5.3.1 Comments on Threats to Sensitive Ecosystems .............................................53 6.0 Summary..........................................................................................................56 Bibliography.................................................................................................................57 Appendix A: Glossary ...................................................................................................61 Appendix B: Summary of Ecosystems Visited and Plot Data................................................62 Appendix C: At-Risk Ecosystems from the BEC Database ...................................................66 Bulkley Valley Centre for Natural Resources Research & Management 3 List of Figures Figure 1. Location of study area .....................................................................................11 Figure 2. Grasslands on south-facing glaciofluvial terrain near Fish Lake. .............................19 Figure 3. Juniper shrub/steppe above Sheslay River..........................................................19 Figure 4. Pine–Lichen forest and pitted outwash plain beside Steamboat Mountain ................20 Figure 5. Floodplain along the lower Taku River ................................................................22 Figure 6. Floodplain at the confluence of Big Salmon Creek and Taku River ..........................22 Figure 7. Overview of Flannigan Slough wetlands..............................................................22 Figure 8. Floodplain of Sheslay River downstream of Hackett Creek.....................................24 Figure 9. Lower O’Donnell River floodplain near Atlin Lake .................................................25 Figure 10. Marl deposit in calcareous wetland near Shaker Lake..........................................26 Figure 11. Calcareous wetland near Como Lake ................................................................27 Figure 12. Sparsely vegetated area at tufa deposit at Atlin Warm Springs ............................28 Figure 13. Houdini Creek Canyon ...................................................................................29 Figure 14. Limestone amphitheatre at junction of Houdini and Yeth creeks ...........................29 Figure 15. Nakina River Canyon .....................................................................................30 Figure 16. Alpine vegetation on limestone near Dry Lake ...................................................31 Figure 17. Alpine vegetation on limestone on Sinwa Mountain ............................................31 Figure 18. Overview of Pine–Lichen vegetation on peridotite bedrock...................................32 Figure 19. Open Pine–Lichen vegetation on peridotite bedrock............................................32 Figure 20. Overview of Yeth Creek landslide on peridotite bedrock ......................................33 Figure 21. Hydromagnesite deposit at Atlin......................................................................34 Figure 22. Chinook salmon spawning dunes on Tatsatua Creek ...........................................35 Figure 23. Former deltas into Lake No Lake .....................................................................37 Figure 24. Bishop Falls on Kwashona Creek......................................................................37 Figure 25. Sinwa Falls resurgence along the Taku River .....................................................38 Figure 26. Columnar basalt formation near Level Mountain.................................................39 Figure 27. Glaciofluvial deposits at Fourth of July Creek.....................................................40 Figure 28. Glaucous bluegrass - Spreading Arctic sedge ecosystem .....................................42 Figure 29. Post-glacial landscape dominated by bedrock, lichens and stunted conifers in White Pass ....................................................................................................................43