Enhance habitat, fish will respond

Sustaining quality fishing in aging reservoirs will require providing good habitat for bass and for anglers.

Table Rock Lake study points to structure helping fishing

Table Rock Lake is a 43,100-acre impoundment on the White River in the Ozark Mountains of Arkansas and Missouri that was built in 1958.

Although this scenic lake continues to provide good fishing, 60 years of water-level fluctuations have severely depleted woody habitat and continue to curtail the establishment of aquatic vegetation. A project led by Missouri Department of Conservation added more than 2,000 structures composed of brush, rocks and stumps to restore habitat and sustain quality fishing.

Not your average brush pile project

The $4 million project funded by the Arkansas Game and Fish Commission, Bass Pro Shops, Missouri Department of Conservation, National Fish and Wildlife Foundation, U.S. Army Corps of Engineers, and the U.S. Fish and Wildlife Service took six years to complete. Specialized equipment was used to add tons of structure. For example, a barge for placing the rock and stumps was 35 feet long, 14 feet wide and capable of carrying and dumping 4,000 pounds.

Water quality is the foundation for good fish habitat, and efforts were directed at reducing nutrient and sediment inputs. An incentive and education program encouraged lakeside property owners to pump out septic tanks before they failed. Another program helped willing landowners stabilize stream banks to reduce sediment inputs to the lake.

Was it a success?

Biological assessments indicated an increase in bass abundance and angler catch rates. SCUBA surveys revealed bass preference for hardwood brush and log piles, while crappies preferred cedars.

Shane Bush, a biologist with the Missouri Department of Conservation who coordinated the project, noted five reasons why the project was worth the money and the extensive effort:

Anglers and guides are fishing the new habitat and catching more fish.

Structures will provide desirable fish and habitat during low-water years when flooded shoreline cover isn’t available.

Sustaining quality fishing in aging reservoirs will require providing good habitat for bass and for anglers.

The septic tank pump-out program prevented the addition of 550 pounds of nitrogen and 120 pounds of phosphorus per year, improving water quality.

Stream-bank stabilization conducted on 3,000 feet of bank reduced sediment input and encouraged similar projects.

The program demonstrated what can be done to rejuvenate aging reservoirs and provided guidance on how to manage habitat more efficiently and economically.

More bass info

A radio-tracking study of largemouth bass conducted by the U.S. Geological Survey, Missouri Cooperative Fish and Wildlife Research Unit and Missouri Department of Conservation provided some important details about how bass used added structure.

Statistical analysis revealed that presence and type of structure, water depth, and distance from shore affected bass habitat selection during day and night.

Among structure types, rock and ledge areas were used the least. Woody structures were used more than rock and ledge, and natural woody structures and installed woody structures were used similarly. Of natural woody structure, “complex woody structure” was used more than “simple woody structure.” Simple woody structure is logs with few branches, and complex woody structure is brush piles. The complex woody structure provides smaller cavities for fish — both bass and their forage — to hide.

Interestingly, boat docks were used most often by bass. This may be specific to steep-sided, cover-limited Table Rock, but nevertheless, it demonstrates that this form of “added habitat” can be a good place for anglers to locate bass.

Day and night locations differed little among structure types, but bass were located in shallower water and closer to shore at night. Daytime depths averaged about 20 feet deep, and nighttime depth averaged about 10 feet.

These findings can help anglers locate bass and help guide future habitat-enhancement efforts. Installing woody fish attractors in 10- to 20-foot depths will have the greatest benefit to bass. In reservoirs with widely fluctuating water levels, fish-attractor placement should be at a variety of depths to benefit fish and anglers during high and low lake stages.

A final note. The Missouri Department of Conservation does not stock bass or crappie in their large, public reservoirs. They rely on the long-term benefits of good habitat to provide quality fishing. Good habitat is good for the fish and good for fishing.

About Hal Schramm 182 Articles
Hal Schramm is an avid angler and veteran fisheries biologist.