As part of the biting insect assessment for the Blacktip Project, traps were required to be set during the peak pest biting midge season months of either August, September, October or November. The month of September was to sample peak season numbers of the main human pest biting midge in coastal areas of Northern Australia, Culicoides ornatus. Peak abundance of C. ornatus occurs around the time of the full moon each month, with numbers generally elevated over a four-five day period. Numbers of C. ornatus can vary dramatically over this four-five day period, although previous studies have shown highest numbers generally occur one day before the full moon and on the day of the full moon. To define the peak numbers of C. ornatus in September, trapping was proposed to occur over a three day period around the full moon, which was to include trapping one night before the full moon, the night of the full moon, and the night after the full moon. This trapping was also likely to indicate peak mosquito numbers for this month, with the exception of Ochlerotatus vigilax, which generally occur 10 days after the monthly high tide.

The ensuing report discusses the new findings and recommendations derived from the September 2004 trapping period, and is to be used as a supplement to the Biting Insect Survey and Assessment report for the Blacktip Project, which was produced in July 2004. The new findings provided in this report can supersede the equivalent findings in the July 2004 report.