The Successful Eradication of European Carp from a Relatively Large Freshwater Lake by Physical Removal

It has now been proven that it is possible to eradicate the introduced pest, European carp, Cyprinus carpio, from a relatively large freshwater lake by physical removal. An integrated approach, taken over 12 years (1995-2007), has achieved their complete removal from Lake Crescent, a 2305 hectare lake in the central highlands of Tasmania, Australia. Although labour intensive, nets, electro-fishing, barriers and traps were deployed to target carp, while protecting the lake’s natural values. Radio transmitters and tracking equipment were used to gather knowledge of seasonable habitat preference and this assisted with gear development. Several mark and recapture population estimates were done during this period using both the Peterson and Schnabel methods of calculation to estimate the remaining number of carp. This allowed a valuable assessment of the techniques being applied. The removal of the last few carp was a challenge that required additional strategies. The capture of a single female carp during the spawning season of 2007 began the process of validating the possibility that this was the last of its sex. It would take three more years and a number of ideal spawning seasons before there was confidence that the goal of eradication had been met.