The implications of introducing a large piscivore ( Lates calcarifer ) into a regulated northern Australian river (Lake Kununurra, Western Australia)

The potential impacts of introducing barramundi ( Lates calcarifer ) for the purpose of recreational fishing into Lake Kununurra, a tropical impoundment in the Kimberley region of Western Australia, are predicted by dietary comparisons with the resident fishes of the lake. Classification of the pooled dietary data identified five major feeding groups based on similarities in food items consumed. There was no significant dietary overlap between L. calcarifer and all species within the lake. The current study demonstrates that adult L. calcarifer fed primarily on teleosts and decopods, and are known to prey on the majority of the fish species found in Lake Kununurra. Although the introduction of L. calcarifer to Lake Kununurra has the potential to influence the resident fish community through competition (for food and habitat) and predation, it is likely that its effects will be minor. However, the lack of any data that would allow estimation of the likely survival of stocked L. calcarifer fry and fingerlings in the reservoir needs to be addressed. Such data are mandatory if a successful fishery is to be developed in the reservoir.