Riparian forest structure and bottom-up drivers of fish production in headwater streams Michael Nelson (FES) Dana Warren (F&W) Ivan Arismendi (F&W)

Study Question: How does changing forest structure in the riparian zone influence fish in headwater streams? Why would forest structure matter? Because forest structure controls light, and the light environment of the stream influences stream food webs and stream temperatures

Study Objectives: Understand how riparian forest structure influences bottom-up drivers of fish abundance and growth in headwater streams Set up preliminary data set for experiments exploring whether selective thinning in the riparian zone to create a more complex canopy structure influences fish in headwater streams

H 1 : Light in headwater streams will be high early in stand initiation, light will decline through the stem-exclusion phase and light will increase again late in stand development Premise behind this study: Changes in light with stand development > 200 % open canopy Meta-analysis of % canopy openness versus stand age across the Pacific Northwest Stand Age

Kiffney et al Includes: Cutthroat trout Sculpin salamanders Premise behind this study: Light can influence biomass of stream biota

Fish Biomass Active management Sedell and Swanson (1984) “A strategy for managing streamside areas for long-term fisheries values would be to keep the large woody materials in the stream during harvest, leave large coniferous trees to serve as a future source of instream debris, and selectively thin dense second-growth stands along the stream to provide a mix of food resources, including algae” This is not a new idea...

HJ Andrews Old growth vs Early mature. Green Mountain Early mature – reference vs Early mature for future thinning Study Design – 12 reaches Pre-treatment data for an experimental assessment of thinning effect on fish, their food, and stream temperatures. Evaluate fish, their food, and stream temperatures at established reach pairs Provides more sites for comparative study

HJ Andrews Old growth vs Early mature. In-stream measurements Riparian Forest Green Mountain Early mature – reference vs Early mature for future thinning Study Design – Sampling Basal area (every 20 m)

HJ Andrews Old growth vs Early mature. Periphyton Chl a (scraping rocks every 5 m) Periphyton Chl a (scraping rocks every 5 m) Macroinvertebrate biomass (Hess sampler 5 samples per reach) Macroinvertebrate biomass (Hess sampler 5 samples per reach) Total fish biomass Salmonid biomass All fish batch marked by reach Fish that are big enough get individual tags (electrofishing, fin clips, and PIT tags) Total fish biomass Salmonid biomass All fish batch marked by reach Fish that are big enough get individual tags (electrofishing, fin clips, and PIT tags) Light on the streambed (every 5 m) Light on the streambed (every 5 m) canopy cover (every 20 m) canopy cover (every 20 m) Temperature (data logged every 5 minutes at the upstream and downstream end of each reach Temperature (data logged every 5 minutes at the upstream and downstream end of each reach Basal area (every 20 m) In-stream measurements Riparian Forest Green Mountain Early mature – reference vs Early mature for future thinning Study Design – Sampling 2 x per year – June/July and August/Sept Stream Habitat (LW, pool area, cover, substrate, gradient, etc.) Stream Habitat (LW, pool area, cover, substrate, gradient, etc.)

HJ Andrews Old growth vs Early mature. Periphyton Chl a (tiles) Periphyton Chl a (tiles) Macroinvertebrate biomass (surber sampler - 5 samples per reach) Macroinvertebrate biomass (surber sampler - 5 samples per reach) Total fish biomass Salamander biomass Fish batch marked by reach Total fish biomass Salamander biomass Fish batch marked by reach Light on the streambed (every 5 m) Light on the streambed (every 5 m) canopy cover (every 20 m) canopy cover (every 20 m) Temperature (data logged every 5 minutes at the upstream and downstream end of each reach) Temperature (data logged every 5 minutes at the upstream and downstream end of each reach) Basal area (5 20 m radius plots) In-stream measurements Riparian Forest Green Mountain Early mature – reference vs Early mature for future thinning Study Design – Sampling 2 x per year – June/July and August/Sept Stream Habitat (LW, pool area, cover, substrate, gradient, etc.) Stream Habitat (LW, pool area, cover, substrate, gradient, etc.)

Basal Area (m 2 /ha) Site Basal Area

HJ Andrews Old growth vs Early mature. Periphyton Chl a (tiles) Periphyton Chl a (tiles) Macroinvertebrate biomass (surber sampler - 5 samples per reach) Macroinvertebrate biomass (surber sampler - 5 samples per reach) Total fish biomass Salamander biomass Fish batch marked by reach Total fish biomass Salamander biomass Fish batch marked by reach Light on the streambed (every 5 m) Light on the streambed (every 5 m) canopy cover (every 20 m) canopy cover (every 20 m) Temperature (data logged every 5 minutes at the upstream and downstream end of each reach) Temperature (data logged every 5 minutes at the upstream and downstream end of each reach) Basal area (5 20 m radius plots) In-stream measurements Riparian Forest Green Mountain Early mature – reference vs Early mature for future thinning Study Design – Sampling 2 x per year – June/July and August/Sept Stream Habitat (LW, pool area, cover, substrate, gradient, etc.) Stream Habitat (LW, pool area, cover, substrate, gradient, etc.)

Light exposure on the stream benthos was quantified using vials of photo- degrading dye Dye photodegradation is then used to estimate Photosynthetically Active Radiation (PAR) base on a strong relationship between decay and measured PAR Measuring stream light Methods details in: Bechtold et al Warren et al Warren et al. in review 24 hour accumulated PAR (umol  m -2 )

McRae Trib – West (4.4 m bankfull)

McRae Creek (STREON) (6.6 m bankfull)

24 hour accumulated PAR x1000 (uE  m -2  s -1 ) Distance (m) (Upstream)(Downstream) Old Growth OG-2G mix Second growth (~60 yrs) McRae Trib – East (3.1 m bankfull)

HJ Andrews Old growth vs Early mature. Periphyton Chl a (tiles) Periphyton Chl a (tiles) Macroinvertebrate biomass (surber sampler - 5 samples per reach) Macroinvertebrate biomass (surber sampler - 5 samples per reach) Total fish biomass Salamander biomass Fish batch marked by reach Total fish biomass Salamander biomass Fish batch marked by reach Light on the streambed (every 5 m) Light on the streambed (every 5 m) canopy cover (every 20 m) canopy cover (every 20 m) Temperature (data logged every 5 minutes at the upstream and downstream end of each reach) Temperature (data logged every 5 minutes at the upstream and downstream end of each reach) Basal area (5 20 m radius plots) In-stream measurements Riparian Forest Green Mountain Early mature – reference vs Early mature for future thinning Study Design – Sampling 2 x per year – June/July and August/Sept Stream Habitat (LW, pool area, cover, substrate, gradient, etc.) Stream Habitat (LW, pool area, cover, substrate, gradient, etc.)

Buffer Is periphyton accrual affect by local light?

Fluorescein decay (ppb) Increased Light > Distance (m) Fluoroscein decay (Δppb) (more loss = more light) μg chl. a/cm 2 Is periphyton accrual affect by local light?

HJ Andrews Old growth vs Early mature. Periphyton Chl a (tiles) Periphyton Chl a (tiles) Macroinvertebrate biomass (surber sampler - 5 samples per reach) Macroinvertebrate biomass (surber sampler - 5 samples per reach) Total fish biomass Salamander biomass Fish batch marked by reach Total fish biomass Salamander biomass Fish batch marked by reach Light on the streambed (every 5 m) Light on the streambed (every 5 m) canopy cover (every 20 m) canopy cover (every 20 m) Temperature (data logged every 5 minutes at the upstream and downstream end of each reach) Temperature (data logged every 5 minutes at the upstream and downstream end of each reach) Basal area (5 20 m radius plots) In-stream measurements Riparian Forest Green Mountain Early mature – reference vs Early mature for future thinning Study Design – Sampling 2 x per year – June/July and August/Sept Stream Habitat (LW, pool area, cover, substrate, gradient, etc.) Stream Habitat (LW, pool area, cover, substrate, gradient, etc.)

upstreamdownstream FL loss X X T1T1 T2T2

upstreamdownstream FL loss X X T1T1 T2T2 Cooling through the reach Difference in stream temperature (C) Warming through the reach

upstreamdownstream FL loss X X T1T1 T2T2 Difference in stream temperature (C) Warming through the reach Cooling through the reach

upstreamdownstream FL loss X X T1T1 T2T2 X X T1T1 T2T2 Difference in stream temperature (C)

X X T1T1 T2T2 (old growth – second growth) Warmer at the end of the old-growth reach Warmer at the end of the second-growth reach

X X T1T1 T2T2 Warmer at the end of the old-growth reach Warmer at the end of the second-growth reach Difference in stream temperature (C) (old growth – second growth)

X X T1T1 T2T2 X X T1T1 T2T2 Difference in stream temperature (C) (old growth – second growth)

HJ Andrews Old growth vs Early mature. Periphyton Chl a (tiles) Periphyton Chl a (tiles) Macroinvertebrate biomass (surber sampler - 5 samples per reach) Macroinvertebrate biomass (surber sampler - 5 samples per reach) Total fish biomass Salamander biomass Fish batch marked by reach Total fish biomass Salamander biomass Fish batch marked by reach Light on the streambed (every 5 m) Light on the streambed (every 5 m) canopy cover (every 20 m) canopy cover (every 20 m) Temperature (data logged every 5 minutes at the upstream and downstream end of each reach) Temperature (data logged every 5 minutes at the upstream and downstream end of each reach) Basal area (5 20 m radius plots) In-stream measurements Riparian Forest Green Mountain Early mature – reference vs Early mature for future thinning Study Design – Sampling 2 x per year – June/July and August/Sept Stream Habitat (LW, pool area, cover, substrate, gradient, etc.) Stream Habitat (LW, pool area, cover, substrate, gradient, etc.)

% of reach area as pools MCT-W Old- growth Second- growth Chucksney Control Manip Loon Control Manip McRae (STREON) Old- growth Second- growth % Pool Area

MCT-W Old- growth Second- growth Chucksney Control Manip Loon Control Manip McRae (STREON) Old- growth Second- growth LW volume (m 3 *100m -1 ) Large Wood (LW) volume

HJ Andrews Old growth vs Early mature. Periphyton Chl a (tiles) Periphyton Chl a (tiles) Macroinvertebrate biomass (surber sampler - 5 samples per reach) Macroinvertebrate biomass (surber sampler - 5 samples per reach) Total fish biomass Salamander biomass Total fish biomass Salamander biomass Light on the streambed (every 5 m) Light on the streambed (every 5 m) canopy cover (every 20 m) canopy cover (every 20 m) Temperature (data logged every 5 minutes at the upstream and downstream end of each reach) Temperature (data logged every 5 minutes at the upstream and downstream end of each reach) Basal area (5 20 m radius plots) In-stream measurements Riparian Forest Green Mountain Early mature – reference vs Early mature for future thinning Study Design – Sampling 2 x per year – June/July and August/Sept Stream Habitat (LW, pool area, cover, substrate, gradient, etc.) Stream Habitat (LW, pool area, cover, substrate, gradient, etc.)

Biomass (g/m 2 ) Vertebrate Biomass Chucksney Control Manip Loon Control Manip MCT-W Old-growth Second- growth McRae (STREON) Old-growth Second- growth

Biomass (g/m 2 ) Vertebrate Biomass MCT-W Old-growth Second- growth Chucksney Control Manip Loon Control Manip McRae (STREON) Old-growth Second- growth

more wood & more vert. biomass more wood but less vert. biomass Less wood and less vert. biomass Less wood and more vert. biomass Relationships between habitat and stream biota Analysis conducted on the DIFFERENCES in each metric between reaches within a stream

Relationships between habitat and stream biota

more wood & more vert. biomass more wood but less vert. biomass Less wood and less vert. biomass Less wood and more vert. biomass Relationships between habitat and stream biota

more wood & more vert. biomass more wood but less vert. biomass Less wood and less vert. biomass Less wood and more vert. biomass

Relationships between habitat and stream biota

* Error bars indicate 2 standard errors of the mean (n=9, 12) (n=11, 14) (n=27, 21) (n=24, 41) P-Value: P-Value: P-Value: P-Value: 0.011

Loss of Fluorescein over 24 hrs Distance (m) (Upstream)(Downstream) Next Steps - Creating Canopy Gaps Loss of Fluorescein over 24 hrs

Next Steps - Creating Canopy Gaps

Next Steps - Filling out data set for paired reach study more wood & more vert. biomass more wood but less vert. biomass Less wood and less vert. biomass Less wood and more vert. biomass Kaylor et al. in Prep.

Next Steps - Filling out data set for paired reach study more wood & more vert. biomass more wood but less vert. biomass Less wood and less vert. biomass Less wood and more vert. biomass Kaylor et al. in Prep.

Thank you Acknowledgements Funding: CoF Forestry’s Fish and Wildlife Habitat in Managed Forests Research Program OSU’s Dept. of Fisheries and Wildlife Fieldwork and data collection: Matt Kaylor Brian VerWay Other intellectual contributions: Lina DeGrigorio Cheryl Friesen Stan Gregory Kathy Keable Julie Pett-Ridge Mark Shultz USFS/BLM fisheries research team Theresa Vallentine Randy Wildman