Comparison of dry ice baited light traps with human bait collections for surveillance of mosquitoes in northern Queensland, Australia.

Adult mosquitoes were collected from April 1984 to September 1985, at 3 sites at or adjacent to the Ross River Dam, north Queensland. The numbers attracted to dry ice baited encephalitis virus surveillance (EVS) light traps and to human bait were similar. Both methods sampled 18 taxa and ranked the abundances of Culex annulirostris, Anopheles annulipes s.l., Aedes vigilax, Mansonia uniformis and Ma. septempunctata similarly at each locality. Significant correlations between the 2 methods were found for all 5 of the dominant species, but were stronger for Ae. vigilax, Ma. uniformis and Ma. septempunctata than for Cx. annulirostris or An. annulipes. Human bait attracted more Cx. annulirostris, Ae. vigilax and Ma. uniformis than the EVS traps. The relative effectiveness of the 2 methods varied significantly with time for Cx. annulirostris and An. annulipes, but both methods revealed similar long term population trends. These data suggest that EVS surveillance may be better suited for sampling Ae. vigilax, and human bait (or alternatively animal bait) or a combination of both methods would be more appropriate for sampling Cx. annulirostris at the dam.