Restoration Potential: Not applicable.
Preserve Selection and Design Considerations: Lands do not need to be protected to provide adequate habitat within the native range.
Management Requirements: It is unclear whether management activities can control this fish. Eradication efforts have often been temporarily successful, but either not all individuals were killed or reintroductions were made. Certainly, eradication efforts must be followed with intensive monitoring. Preventative measures, such as barrier construction to obstruct the paths into uncolonized tributaries, should be taken when feasible. Transport and introduction of non-native fishes should be curtailed. Natural flooding regimes in western streams could aid in keeping populations in check. Meffe (1984, 1985) showed that flooding removes proportionally more mosquitofish than native topminnows.
Regulations should be drafted and/or enforced that discourage transport and stocking of non-native fishes into uncolonized habitats. An education program targeted at fishers relating the damage non-native fishes do to the environment should be implemented. An education program targeted at state and federal agencies should be implemented explaining the detrimental impact of stocking mosquitofish for mosquito larvae control. Natural barriers can be enhanced, or new barriers built to prevent the invasion of non-native fishes. Barrier design should not significantly alter stream flow and the potential impact on natural upstream and downstream movements of native fishes should be assessed. Barrier design must be approved by appropriate agencies and the appropriate Desert Fishes Recovery Teams.
Monitoring Programs: Information on mosquitofish is usually gathered incidental to other monitoring programs.
Management Research Needs: Because this is a wide ranging eastern species, much of the biology is known in the native habitat. The following specific topics are research areas that should be addressed relative to locations where introductions have been made: (1) rate of colonization in stream reaches after flooding events or after new introductions, (2) competition for food with native species, comparing diets of all life stages, (3) reproductive potential in introduced locations, emphasizing comparisons with native species, (4) aggression and predation directed towards native species in field studies, and (5) an evaluation of past eradication efforts, and (6) an analysis of sites where mosquitofish and native species have coexisted for several years (e.g. Black Draw, San Bernardino National Wildlife Refuge), and comparison to sites where mosquitofish and native species do not coexist.