INTEGRATING AQUATIC RESTORATION & RIPARIAN BUFFER MANAGEMENT

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1 INTEGRATING AQUATIC RESTORATION & RIPARIAN BUFFER MANAGEMENT Dr. Deanna H. (Dede) Olson Research Ecologist Pacific Northwest Research Station US Forest Service

2 Landslide Potential Sediment Bank stability Overridge connection Riparian tree growth Stream Temp. Stream species abundance Riparian Buffers (considerations) Down wood Riparian species abundance Stream habitats There are numerous considerations for riparian buffer management Riparian habitat & dispersal Fire mitigation Stream flows Climate change mitigation

3 AMONG FOREST ECOSYSTEM SERVICES, SPECIES AND WATER ARE THE MOST TREASURED AQUATIC NATURAL RESOURCES Rare endemic aquatic species of greatest concern

4 Endemic species are becoming more of a concern with the 6th Major Mass Extinction Event for Earth Most imperiled: Aquatic biodiversity and their ecosystems Likely due to high endemism and cryptic spp. Vulnerable to losses: >50% of freshwater turtles >40% freshwater fishes 30-40% of amphibians (>80% occur in forests) 25% of mammals 12% of birds

5 Riparian Areas are Biodiversity Hotspots for Wildlife in Western Forests 53% of general wildlife are riparian associates in OR and WA 75% of vertebrates are riparian associates in the OR Blue Mtns 79% of vertebrates are riparian associates in the OR Great Basin 36% of westside old-growth associated vertebrates are tied to riparian habitats

6 Dispersal Early Seral & Late Seral Species Fire Disease Chemicals Invasives Species of concern considerations Key Ecological Functions Habitat Genes to Communities

7 Aquatic ecosystems are multi-state * Aquatic-riparian species differ by location and over time * Aquatic-riparian habitats differ by location and over time Olson et al. 2016; Penaluna et al. 2016; Reeves et al Reference conditions are multi-state

8 Multi-state example: Up to 80% of stream network length may be headwater streams

9 Multi-state example: With Natural Disturbances, aquatic-riparian species and habitats change over time Here, landslide-prone areas deliver down wood and sediment to streams NOTE: Headwater distribution

10 Multi-state example: Shrinking Heads With Climate Variation Olson and Burton in prep.

11 Key Riparian Management Considerations for Fish Habitat Intrinsic potential Stream temperature and thermal loading Down wood recruitment Debris flow potential Erosion/Bank stability Substrate distributions Fire regime

12 Key Riparian Management Considerations for Amphibian Habitat Intrinsic potential Stream temperature/thermal loading Down wood recruitment Debris flow potential Erosion/Bank stability Substrate distributions Fire regime Amphibian species Headwater stream habitats Riparian habitat conditions Overland connectivity

13 Key Riparian Management Considerations for Riparian Systems Intrinsic potential Stream temperature/thermal loading Down wood recruitment Debris flow potential Erosion/Bank stability Substrate distributions Fire regime Amphibian species Headwater stream habitats Riparian habitat conditions Overland connectivity Accelerating tree growth (and future large down wood) Promoting minority tree species Promoting structural heterogeneity Habitat for >100 LSOG species Habitat for 800 species of concern

14 Lessons Learned Riparian buffers serve multiple roles Several benefits of 15-m (50- foot) minimum-width buffer with our thinning treatment Consider multi-state ecosystem Consider hedging uncertainties with a mix of buffer approaches Consider most important risks per area 50 ft 20 ft

15 Thank You! Dede Olson 1-hour webinar on this topic at:

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17 DENSITY MANAGEMENT AND RIPARIAN BUFFER STUDY OF WESTERN OR (1994 TO PRESENT) OBJECTIVE: Examine effects on headwater species and habitats of alternative buffer widths with upland thinning TPA ( TPH) 80 TPA (200 TPH) 35 TPA (85 TPH)

18 After 1 and 2 Thinnings 15-m and 70-m buffers increased Dunn s and Torrent salamander numbers after 2 thinnings 6-m buffers decreased Dunn s salamanders after first thinning, and Dunn s and Torrent salamanders after 2 thinnings

19 After 1 and 2 Thinnings: No detectable affect on fish and most stream habitat components Down wood recruited from within 15 m of stream More early-decay stage wood from 6-m buffer treatment No effect of buffers on stream temperatures Riparian amphibian habitats and activities within 15 m of stream Edge effect increasing riparian tree growth to 15 m of buffer edge

20 WATERSHED/LANDSCAPE-SCALE TOOLS e.g.: Reeves et al model CRITERIA: FISH INSTRINSIC POTENTIAL, THERMAL LOADING, EROSION POTENTIAL &DOWN WOOD DELIVERY 4 MANAGEMENT CLASSIFICATIONS Class 1. Most Ecologically Important Fish-bearing Streams Qualifications Intrinsic potential > 0.5 OR > 10% increase in thermal loading potential OR Medium-high erosion potential 2. Other Fish-bearing Streams Had none of the qualifications for most ecologically important streams 3. Most Ecologically Important Non-fish Bearing Streams Medium-high probability of delivering of wood to fish bearing stream 4. Other Non-fish Bearing Streams All other non-fish bearing streams

21 Fish Bearing Ecologically Imp t. Other Variable Buffer Widths Non- Fish Bearing Ecologically Imp t. Other Managed for Ecological Values Ecological Forestry with tree tipping One tree height One tree height One tree height One tree height 100 feet 50 feet