1. Introduction to Fisheries Management
Habitat Management
December 7, 2004
Chapters 10 and 11
Introduction to Fisheries Management

2. Lake and Reservoir Habitat Management
Stream Habitat Management

3. Lake and Reservoir Mgt. 200 ha or larger (~500 acres)
Lakes – natural bodies of water
Reservoirs – artificial controlled lake

4. Common Habitat Problems in Lakes
Nutrient Loads and Eutrophication (Oligotrophic, Mesotrophic, and Eutrophic)
Dissolved Oxygen
Acidification
Nuisance Vegetation
Deterioration of Shoreline Habitat
Lack of Structural Complexity

5. Eutrophication and DO
Stratification acts as habitat; temperature and DO; epilimnion often too hot, but hypolimnion often has no DO.
Destratification, Aeration, Control of Nutrient Inputs, Biomanipulation

6. Acidification
Acid precipitation a large problem in part of Europe and North America
Treatment with lime; retention time >6 months.

7. Nuisance Vegetation Chemical, mechanical, and biological controls
Mechanical controls can be implemented to improve fish habitat (increases edge for ambush predators)
Reduce amount of nutrients coming in to the lake/reservoir

8. Lake Shore Erosion Control
Grading Slopes
Construction of retaining walls
Revegetation
Reducing energy of incoming waves
Wake limits

9. Fluctuations in Water Levels
Reservoirs, particularly hydropower peaking facilities, can fluctuate greatly and dewater fish nests and reduce habitat availability
Reduces aquatic vegetation

10. Management with Water Fluctuations
Many fishes use flooded riparian zone (northern pike, perch, largemouth bass)
Control of aquatic vegetation (both to improve populations and reduce nuisance species)
Devils Lake, WI
Lake Powell, AZ

11. Shoreline Management
Riparian zone is the area of the greatest direct influence on lakes
Many lakes require landowners to maintain riparian conditions

13. Artificial Structures
Generally best in habitat limited systems
Attraction vs. Production Debate
Provide a good opportunity to interact with the public.

14. Stonewall Jackson Lake, West Virginia