Large-scale trapping of sheep blowflies in the northern North Island of New Zealand using insecticide-free traps

Abstract

Large-scale trapping of sheep blowflies (Diptera: Calliphoridae) was undertaken on a mixed farming property in the north of the North Island of New Zealand over 3 consecutive summers. Traps were placed at a density of 1 trap110 ha and baited with fresh sheep offal every 2 weeks. No insecticide was used in the 150-L traps. The most effective bait trialled was sheep offal <2 weeks old. There was no significant effect of trap colour or trap site on the number of blowflies caught. A 95% decline 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.