Although some put-grow-take stocking programs are remarkably successful and produce great social and economic benefits, these programs were not intended to solve nor address some key problems that face the Great Lakes. A number of persistent issues remain:
Why strive for fisheries with increased contributions from wild fish? Implied here is a reduced dependency on stocked fish. Does this vision statement mean immediate cutting of programs before self-sustaining replacements come available? Clearly, the stocking programs must be maintained while self-sustaining populations are developed. Otherwise, for example, without predatory fish Lakes Michigan, Huron, and Ontario would quickly revert to an alewife dominance characterized by declines of native fishes and by diminished fishing opportunities. Reproducing fish populations offer the best respects for maintaining food chain efficiency for sustainable production of predatory fish in the Great Lakes. Stocked fish lack the resilience of wild fish and are inherently less likely to persist in a changing environment. In his vision statement, stocked fish are seen as surrogates for wild fish, perhaps for extended times in areas where fish communities and habitats have been seriously impaired. During these periods, however, self-sustainability should remain the goal and opportunities for increased self-sustainability should be favored over increased opportunities for hatchery based fisheries, when the two goals conflict.
Many native fish species are now extinct in some or all of the Great Lakes, and these extinctions result in a loss of biological diversity. Examples include the deepwater sculpin and Atlantic salmon in Lake Ontario and lake trout in Lakes Michigan and Erie. A more stable fish community that provides sustainable benefits to society will require improved, coordinated efforts to prevent further losses of native species and populations and to store, where feasible, those which have become depleted or locally extinct. Fortunately, substantial progress in the restoration of native species has occurred in the Great Lakes (e.g., in Lake Superior for lake trout, in Lake Erie for walleye, and in Lake Michigan for yellow perch and deepwater ciscoes). The Commission will continue to support efforts to prevent further losses of native species and to restore those that have been depleted.
The accidental introduction of non-native species has been a disruptive force in the Great Lakes ecosystem. The unintentional introduction of non-native species (such as the ruffe, spiny water flea, and zebra mussel) can cause ecosystem perturbations that result in unstable fish communities, reduced diversity of native biota, and reduced societal benefits. Sea lamprey and white perch are examples of this process at work. The Commission will continue to work towards prevention of accidental introductions of nonnative species. The 1990 joint report by the International Joint Commission and the Great Lakes Fishery Commission on non-native species and the shipping industry is an example of this commitment.
To produce sustainable benefits to society, the remaining habitats essential healthy aquatic ecosystems must be protected and those that are degraded must, where feasible, be restored. Protection and restoration of habitat are fundamental to the existence of viable populations of native species and to the diversity of aquatic communities. Of particular importance, improved stream habitats will encourage natural reproduction and a reduced dependency on hatcheries for introduced species such as rainbow trout and the Pacific salmons and native species such as brook trout, walleye, and Atlantic salmon. Although stocking programs have kindled public interest in the Great Lakes, the tremendous success of these programs may blind society to the need for protection and restoration of Great Lakes habitats. To attain full restoration of Great Lakes fish communities, stocking of hatchery fish should be viewed as an interim or supplemental management tool until degraded habitat and natural populations are rehabilitated.
The presence of persistent toxic substances in the aquatic food chain (including the flesh of fish) threatens the social and economic benefits currently realized from Great Lakes fisheries and may reduce the potential for restoration of fish species and populations. Some fish are so contaminated that they are deemed unsafe for consumption by humans. Contaminants in fish may affect the reproductive capability of fish populations and hinder achievement of restoration objectives for native pecies such as lake trout. Consumption of Great Lakes fish also affects the health of birds and mammals in the basin. The Commission believes that the potential for detrimental ecosystem and societal effects from toxic substances requires a specific milestone.
Partnerships with other agencies and institutions are
essential for the achievement of the ecosystem vision statement by the
end of the decade. Stocking, fishery regulation, aquatic-habitat management,
species restoration, control of non-native species, and reduction of toxic
chemicals are responsibilities shared by a variety of federal, international,
provincial, state, and tribal agencies. Development of complementary programs
among agencies that suppose this Strategic Vision will be encouraged by
the commission. For example, the Commission will support coordinated efforts
by agencies to implement the Great Lakes Water Quality Agreement to reduce
or eliminate existing toxic discharges and to remediate, where feasible,