Restoration Ecology: Rivers and Streams WFC 10 29 Nov 2010 Restoration of ecosystems often involves creating new systems with only partial resemblance to the original ecosystems Lisa Thompson Fisheries Extension Specialist Wildlife, Fish, & Conservation Biology Department University of California, Davis Outline Class poll initial opinions Restoration goals Adaptive management Case study Eagle Lake rainbow trout Impacts Restoration actions Monitoring studies Group discussion Updated class poll Initial Poll 1. Should a completely natural system be the ultimate goal of a restoration project? (Yes/No/Maybe) 2. Should we do restoration projects that will require perpetual maintenance? (Yes/No/Maybe) 3. Is it acceptable to kill wild animals of one species in order to conserve another species? (Yes/No/Maybe) Potential Restoration Goals Adaptive Process Natural, pristine, dynamic system, OR Human-engineered system (ample water storage for droughts, no floods), OR Modified system Many natural processes occurring Most native species in adequate abundance to ensure survival Modify Strategy Update Model Actions Adaptive Research Monitor Evaluate Response 1
Eagle Lake Rainbow Trout Oncorhynchus mykiss aquilarum Eagle Lake Alkaline lake Long lifespan, large size Species of special concern Heritage trout US Forest Service R5 sensitive species Two petitions for ESA listing Perennial Eagle Lake and Pine Creek Intermittent Pine Creek Length = 63 km (~40 miles) Elevation = 1,750 m (~5,700 ) Low gradient mountain meadows Steeper gradient reaches in pine forest 11 km of creek has perennial flow (7 miles) ~21 springs Pine Creek Flows Lower reaches of creek dry up by summer Natural! Historical Rainbow Trout Life Cycle Eggs develop 1-3 months Alevin rear 1-5 months Fry emerge early summer CREEK Adults spawn in headwaters Parr rear for a year LAKE Adults return to spawn Juveniles migrate to Eagle Lake in spring 2
Impacts Overgrazing Road construction Highway & railway culverts Brook trout introduction - 1940 Fish velocity barriers - 1959 Habitat Degradation Stream channel poorly defined Road Crossing Passage Barriers Hanging Culvert Exotic species Brook trout Velocity Barrier 3
Velocity Barrier Fish Trap Rainbow trout have not migrated and spawned regularly in 50 years Current Rainbow Trout Life Cycle Eggs develop 1-3 months Eggs are fertilized Alevin rear 1-5 months Fry rear in hatchery HATCHERY Parr rear up to 30 months Adaptive Process Watershed restoration Passage improvement Decrease invasive species Modify Strategy Actions Adaptive Monitor LAKE Update Model Research Evaluate Response Adults are spawned and returned Juveniles are planted to Eagle Lake Restoration Actions Pine Creek Coordinated Resources Planning group CRMP Started in 1987 Improved grazing practices Improved passage at highway and railway crossings Pine Creek Watershed Restoration Channel with collapsing banks Channel with improving banks Old culvert New box culvert 4
Uncertainties Adaptive Process Has this restoration been enough? Brook trout still there Can Eagle Lake rainbow trout complete their natural life cycle? Migrate Spawn Rear Watershed restoration Passage improvement Decrease invasive species Modify Strategy Update Model Actions Adaptive Research Monitor Evaluate Response Monitoring Studies Spawning Migration Track upstream migration Relate movement to environmental factors Spawning Rearing Reduce brook trout population Compare Pine Creek and Bogard Spring Creek Migration - Tagging PIT (passive integrated transponder) tag Floy tag Migration - Tracking Maximum Trout Migration Distances Migration of Eagle Lake rainbow trout spawners has been tracked since 1999 Tracked 20 fish in 2008 5 stationary PIT antennas Solar panels 5
Distance Traveled by Trout vs. Seasonal Average Flow Distance Traveled by Trout vs. April Snowpack (Silver Lake) 40 35 40 35 y = 0.31x - 4.14 R 2 = 0.19 eled (km) Distance Trave 30 25 20 15 10 y = 11.43x + 5.71 R 2 = 0.34 Distance (km) 30 25 20 15 10 5 5 0 0 0.5 1 1.5 2 2.5 Seasonal Average Flow (m 3 /s) 0 0 20 40 60 80 100 120 Snowpack (Water Content, cm) Spawning Transported ELRT spawners to upper watershed in spring 2007 and 2009 Monitored for presence of spawners & redds Young rainbow trout seen in 2009 Rearing - Brook Trout Removal Experiment Bogard Spring Creek - Treatment Triple-pass pass electrofishing X 3 km Removed brook trout Pine Creek - Control Electrofished 5 X 50 m sites All fish returned to creek Electrofishing Sites Bogard Spring Creek Hwy 44 3 Trout in Bogard Spring Creek - 2007 4,887 brook trout removed (110 kg); 170 Eagle Lake rainbow trout returned Brook 2 Rainbow Pine Creek ind/m m² 1 0 1 2 3 4 5 6 7 8 9 101112131415161718192021222324252627282930 Confluence Sites Headwaters 3 km 6
Brook Trout Removal Experiment 2008 & 2009 Brook Trout Density Changes - Bogard Spring Ck Repeated treatment on Bogard Spring Creek Triple-pass pass electrofishing X 3 km Removed brook trout Repeated sampling of Pine Creek control sites Large brook trout decreased but many juveniles remain 2008 2007 2009 Confluence Headwaters Brook trout density decreased, but Remaining brook trout in better condition and reproducing at younger age Carmona-CatotCatot et al. 2010 More Uncertainties Adaptive Process Were enough brook trout removed? Will brook trout move from Pine Creek to Bogard Spring Creek? Will juvenile rainbow migrate to the lake? Will climate change affect flow & migration? Watershed restoration Passage improvement Decrease invasive species Modify Strategy Actions Adaptive Monitor Update Model Research Evaluate Response Saving native brook trout Rapid River, Maine Trout Unlimited, and Maine Department of Inland Fisheries and Wildlife Prevent further invasions of brook trout waters by smallmouth bass Identify methods to reduce smallmouth bass Implement measures to reduce bass predation on juvenile brook trout http://www.tu.org/conservation/east ern-conservation/brook- trout/about/rapid-riverriver Discussion / Updated Poll 1. Should a completely natural system be the ultimate goal of a restoration project? 2. Should we do restoration projects that will require perpetual maintenance? 3. Is it acceptable to kill wild animals of one species in order to conserve another? 4. What if One of the species that is killed was introduced? We can kill the introduced/invasive species painlessly? The native species may be able to survive, although at very low abundance? We can move the introduced / invasive species back to its native habitat? 7
Take home messages Human activities can degrade habitat Restoration may result in a modified system actions need to be Monitored Experiments 8