| Abstrakt: |
Speckled Peacock BassCichla temensisare being considered for introduction into Puerto Rico to provide sportfishing opportunities and biological control for invasive New World cichlids. The proposed introduction was evaluated by following the American Fisheries Society’s recommended seven-step approach to introducing nonnative fish. This paper documents the evaluation process, which included a rapid risk screening approach using the Fish Invasiveness Screening Kit (FISK) version 2 and a series of controlled experiments on prey selection, agonistic behavior, and competition. The overall FISK score was 6 with a certainty factor of 0.84, placing the introduction in the medium-risk category (0–18) for invasiveness. Many of the attributes elevating this species to the medium-risk designation were the same attributes desired during species selection, including generalist feeding behavior and large body size, which are required for predation on New World cichlids. In controlled experiments, Speckled Peacock Bass consumed all cichlid species offered, suggesting that they may have potential as a biological control agent, although some selectivity in species and size was observed. Speckled Peacock Bass showed aggression toward conspecifics and other species in a mesocosm environment, but aggression generally decreased with time. There was no evidence of negative effects on Largemouth BassMicropterus salmoidesin terms of growth or condition via aggression or competition in controlled small-pond experiments. Although some downstream movement from receiving reservoirs would be possible, downstream habitats are unsuitable for establishment of this species. The greatest risk may be unauthorized movement by anglers to other reservoirs where this species is not desired. It is the conclusion of this evaluation that Speckled Peacock Bass will consume New World cichlids and that the risks of introduction are acceptably low. Thus, introduction may proceed on a limited scale with proper scientific evaluation and public outreach directed at reducing unauthorized translocation by anglers. Received October 12, 2016; accepted June 19, 2017 Published online August 31, 2017 [ABSTRACT FROM AUTHOR] |
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