Stocking Fish as a Management Tool?
Stocking Fish as a Management Tool?
District V Fisheries Supervisor
Spanish Fort, Alabama
"The state needs to restock this lake!!!" That’s a common comment from unsuccessful anglers and a common request made to the Fisheries Section of the Division of Wildlife and Freshwater Fisheries. Stocking fish is a management tool that the Alabama Wildlife and Freshwater Fisheries Division uses only in appropriate situations.
Fish hatcheries have long been an important component of fisheries management agencies and stocking certainly has a place in fisheries management. A common misconception among many anglers is that stocking fish is a magic cure for improving fishing in any body of water and that fishing will always improve after stocking.
Stocking of hatchery-produced fish can be effective, but only in specific instances. A general opinion in fisheries management is that the productivity of a body of water cannot be increased simply by stocking native fish, which already live and reproduce in the habitat naturally. The abundance or standing stock of a particular species of fish in a specific habitat will vary within a limited range and is dependent upon ecological factors. Stocking hatchery-produced fish in waters where there is an existing population of native fishes will not necessarily increase fish abundance or improve fishing. Stocking can sometimes be counterproductive.
If stocking has limited success in improving fishing, why does the Division of Wildlife and Freshwater Fisheries stock fish anywhere? There are circumstances where stocking hatchery-produced fish can benefit anglers. Stocking guidelines of the Fisheries Section are based on years of research and management experience. The guidelines produce tangible benefits to Alabama anglers. Conditions where stocking hatchery fish is justified include the following:
Stocking waters that contain no fish: The most obvious example of this situation is a newly constructed or renovated lake or pond. The Wildlife and Freshwater Fisheries Division has suspended it sale of bluegill, redear sunfish, and largemouth bass for ponds, but fish are available from private hatcheries. Fisheries Section biologists will visit new or renovated ponds from October through January to offer advice to pond owners about stocking. Private ponds are the second most heavily fished waters in Alabama. Another example of this type of stocking is to restore fish in public waters that have been depleted of fish by a fish kill.
"Put and take," or "put, grow, and take" stocking: When the fish being stocked will not spawn successfully in the water body, periodic restocking is necessary to maintain a population. Stocking of channel catfish into public fishing lakes is an example of "put, grow, and take" stocking. Although channel catfish may spawn in ponds, bass are such efficient predators of small channel catfish in ponds that catchable-sized catfish must be stocked. A unique "put and take" fishery exists in the tailwaters below Smith Lake in the Sipsey Fork. Rainbow trout are artificially maintained in a native warm water fishery due to the abnormally cold water discharges from Smith Lake. Since native fish and biota are unable to maintain a healthy fishery, a niche was created for survival of the rainbow trout.
Stocking to restore a native species that has declined in numbers due to some habitat alteration: Alabama’s striped bass stocking program exemplifies this kind of stocking. The life history of striped bass involves both fresh water and salt water. Striped bass can live in rivers, estuaries and the ocean, but they migrate upriver for spawning. In Alabama, and most states where striped bass occur naturally, rivers have been dammed, and spawning areas have been blocked and flooded. Although a landlocked, spawning population of striped bass now occurs in northeast Alabama, the present striped bass populations in Alabama rivers and reservoirs are largely the result of annual stocking by the Alabama Wildlife and Freshwater Fisheries Division.
Stocking to introduce a new species or new genetic strain: Florida largemouth bass and hybrid striped bass are instances of introducing new species or a different genetic strain. These fish have value in fishery management and have been stocked in various waters.
Stocking for research purposes: Fisheries biology is a science, and there are many unanswered questions. Sometimes fish are stocked to aid in finding answers to these questions. Examples of this kind of stocking might involve the evaluation of introducing a new fish species or study of the exploitation of a specific fish species. A Baldwin County research project involving the stocking of tagged fish in selected tidal fresh waters is one example. This study will determine the possible benefits to anglers of stocking catfish and hybrid striped bass in tidal streams that are impacted by residential development.
Stocking fish will always be an integral aspect of fisheries management in Alabama. But stocking is only one fishery management tool – one that will be used by the Alabama Wildlife and Freshwater Fisheries Division when it is the right tool to use.
Written in September of 1999, updated in June of 2009.
Note: In Alabama, it is illegal to stock or move a bass or any fish, mussel, snail or crayfish to any public water without a permit.