Elimination of invasive alien fish species from a pond in Fukuoka Prefecture

Invasive alien fishes such as Micropterus salmoides and Lepomis macrochirus were eliminated from a pond in Fukuoka Prefecture (Japan). We selected the Shirouzu Pond from among 12 ponds by screening on the basis of the distribution and population of invasive alien fishes, rate of revetment with concrete, feasibility of pond drying methods, and presence of threatened fish and insect species. In the Shirouzu Pond, Micropterus salmoides (70 kg) and Lepomis macrochirus (120 kg) were collected and eliminated in 1 day. In the case of other ponds, we estimated that the elimination of invasive fishes was required in the Chinzei Pond, which had several threatened insect and fish species. We conducted ecological research on the invasive fishes present in the pond because it was not possible to conduct pond drying methods in this pond. The finding of this research suggested that capturing the larvae and juveniles of the invasive fishes in the growth area or destroying the spawning sites were the best methods for eliminating these species from the pond.