Key Factors Limiting Trout Populations in Appalachian Streams

1. Key Factors Limiting Trout Populations in Appalachian Streams • Acid Precipitation • Harvest • Dispersal Barriers (culverts) • Increased Temperature (reduced shading, climate change) • Competition with / Predation by Non-Native Trout (browns and rainbows) • Poor Habitat Quality (floods, no LWD) • Sedimentation and High Turbidity (eroding banks and improper land use)

2. Acid Precipitation pH of rainfall = 4.5 Estimated 25% coldwater streams in WV are unnaturally acidic

3. Effect of Acid Precip is to Reduce Egg, Larva, and Juvenile Survival Alk > 20 mg/L Alk < 5 mg/L

4. Angler Harvest Large, mobile trout are highly vulnerable to angling mortality and are probably being “culled” from larger streams that are stocked and receive extremely high fishing pressure.

5. Sources of Brook Trout Mortality(from Alexander 1979, Au Sable River, MI)

6. Dispersal Barriers Movement Barriers, such as culverts, keep adult trout from being able to move between reproductive, foraging, and refuge habitats.

7. Reduced Shading and Increased Temperature • Historically, Appalachian watersheds were completely forested. • Large-scale timber harvest and building of road and railroad networks have reduced streamside shading . • While this may increase productivity, it also results in higher than normal summer temperatures.

8. Poor Habitat • Some of the problems are natural (no boulders, naturally wide and shallow). • Without question there is much less LWD in Appalachian streams now than there was historically. • Other problems created by flood damage. • Still other problems we create ourselves (dredging, poor use of floodplains, etc.).

9. Sedimentation and Turbidity • Erosion and sediment transport are important natural processes. • But, we do lots of things that produce unnaturally high rates of erosion, turbidity, and sedimentation. • Erosion – movement of sediment particles from the terrestrial landscape by water • Sedimentation – deposition of sediment particles. • Turbidity – cloudiness of water produced by sediments suspended in the water column.

10. Sedimentation and Turbidity • Reduce the quality of spawning substrate • Filling of juvenile rearing areas • Loss of aquatic invertebrate habitat • Decrease abundance and richness of inverts WV DEP

11. Sedimentation and Turbidity • Reduction of light penetration and visual clarity • Increased physiological stress and susceptibility to disease • Reduction of growth due to active foraging

12. Brook trout density and suspended sediments

13. Coldwater Stream Management Approaches • Harvest Regulations (reduce mortality rates) • Stocking (supplement populations) • Acid Remediation (increase food availability, increase reproductive success) • Instream Habitat Management (increase bank stability and habitat complexity) • Best Management Practices (reduce sediment delivery to streams, and maintain streamside shading)

14. Regulating Harvest (see Ch. 17) Put that thing back, it’s way too small! I told you Catch and Release would make the fishing better here! What, did you steal that thing out of the truck? Catch it, kill it, eat it!

15. Tools of Harvest Regulation • Fishing Seasons (e.g., trout season) • Creel Limits (e.g., six fish per day) • Size Limits (e.g., release all fish less than 12 inches) • Slot Limits (e.g., release all fish less than 6 inches and greater than 14 inches) • Fishing Gear Restrictions (e.g., fly-fishing, barbless hook, no power-bait, no gas-powered motors, no dynamite) • Catch-and-Release

16. Stocking (see Chapter 14) • Every state except Louisiana, Florida, and Mississippi have trout stocking programs (Epifanio 2000) • ~137,000,000 trout stocked including ~52,000,000 “catchables” • Goals and objectives of stocking need to be set and considered in all management decisions

17. Role of Stocking in Fisheries Management • Enhance existing fishery • Meet angler demands • Satisfy public and political pressure • Supplement a year class • Reestablish a population • Increase angler satisfaction • Others?

18. Types of Stocking Programs • Put and take • Put, grow, and take • Introduction • Re-introduction www.wvangler.com

19. Stocking Considerations • Biological • Social • Economics

20. Biological Consideration • Genetic Conservation (Dowling and Childs 1992) • Biotic Interactions (Fausch & White 1981, Goodman 1991) • Overharvest of wild stocks (Moring 1993, Mezzera and Largiader 2001) • Disease (Epifanio 2000) • Mask real biological problems?

21. Social Considerations • Provides a reasonable probability of success. • Takes fishing out of a “back to nature” context. • Becomes very difficult not to stock once you’ve started. • Concentrates anglers which often leads to dissatisfaction. • Diversifies angling experience…so long as it is not all an agency does.

22. Economic Considerations • Programs are often not self-sufficient and comprise large portions of the state’s management budgets and resources. • Money spent on stocking could have been used elsewhere for longer term benefits (States’ spend $3.40 on stocking for every $1 on habitat restoration; Nickum, McGurrin, and Duff 1994) • Economic costs of trout stocking may exceed the benefits (Johnson et al. 1995, Loomis and Fix 1999).

23. Non-Native Salmonids • Trout have been stocked VERY widely translocated (brown trout in US, brook trout in western US, rainbow trout eastward, etc.) • Compete for resources with natives • Hybridization, particularly between rainbows and cutthroat trout

24. Controlling Non-Native Trout • Can be socially & politically difficult Some extensive programs: • Remove rainbow trout in the GSMNP and restore native brook char • Remove brook trout in many western states to restore native cutthroat • Remove non-native lake trout in Yellowstone Lake to help Yellowstone Cutthroat trout

25. Acid Precipitation Mitigation • Adding limestone to treat acid precipitation (limestone sand piles and limestone slurry dosers). • Increases pH and Ca++. • Reduces dissolved Al. • Incomplete recovery (sedimentation, does not restore other chemical constituents, isolation of restored streams).

26. BMP Guidelines for Forest Operations in WV (Martin and Hornbeck, 1994) • Slope of logging roads and skid trails • Water bars and broad-based dips • Culverts at stream crossings • Buffer strips • Proper removal of logging slash • Location of landings and road system • Close operations in unfavorable conditions • Rehabilitation of landings and skid roads.