LARGE-SCALE TRAPPING OF SHEEP BLOWFLIES IN THE NORTHERN NORTH-ISLAND OF NEW-ZEALAND USING INSECTICIDE-FREE TRAPS

Large-scale trapping of sheep blowflies (Diptera: Calliphoridae) was u ndertaken on a mixed farming property in the north of the North Island of New Zealand over 3 consecutive summers. Traps were placed at a den sity of 1 trap/10 ha and baited with fresh sheep offal every 2 weeks. No insecticide was used in the 150-L traps. The most effective bait tr ialled was sheep offal <2 weeks old. There was no significant effect o f trap colour or trap site on the number of blowflies caught. A 95% de cline in the principal flystike blowfly, Lucilia cuprina, was recorded . Flystrike incidence at the site was low during the study so that the effect of trapping on sheep myiasis could not be determined.