CBER's invasive fish research programme

Koi carp removal from pond at Apata

Environment Bay of Plenty (EBOP) and DOC BOP contracted CBER's electrofishing boat and its crew (Brendan Hicks and Alex Ring) to fish a pond in private land near Apata, Bay of Plenty. Apata Pond has an area of about 0.25 ha; its length is 150 m, and its width is 40 m. Its maximum depth is 3.5 m, but much of the area is considerably shallower.

Koi carp were removed from a pond on private land near Apata (175.994333oE, 37.650778oS), Bay of Plenty, on 18 February 2004 with the full cooperation of the landowner. In 3 hours we removed 5 large adult koi carp (total biomass 19.0 kg, or 76 kg/ha). We determined by scale analysis that all koi carp (2 males and 3 females) removed from Apata Pond were 8 years old and sexually mature. We also caught adult inanga and shortfinned eels in the pond, but no juvenile koi carp were caught. Since that time, no koi have been seen in the pond, so it is possible that one intensive boat electrofishing session eradicated the koi carp from this habitat. If you have Google Earth, click here to go to the site location. This opens best with Mozilla Firefox browser.

apata-apata-pond.jpg

Apata Pond


Electro Fishing


Koi carp immobilised at the anode


Koi carp from Apata (521-564 mm, 3.27-4.33 kg)


Reference

Hicks, B.J., D.G. Bell, C.A. Ring, and G.W. Tempero. 2004. Boat electrofishing survey of Apata Pond and Lake McLaren. CBER Contract Report No. 33. Client report prepared for the Department of Conservation, Bay of Plenty Conservancy, and Environment Bay of Plenty. Centre for Biodiversity and Ecology Research, Department of Biological Sciences, The University of Waikato, Hamilton. 14p.