Survey of forensically-important Calliphoridae in Kingston and St. Andrew, Jamaica, West Indies

Abstract

The first research to be done in Jamaica on forensically-important species was conducted at the Government of Jamaica Forensic Laboratory in Kingston and St. Andrew in two phases. Phase 1was conducted from July 5 to July 24, 2007, and phase 2 was conducted from February 11 to February 28, 2008. In the phase 1 study, one local black colored Landrace pig (Sus scrofa L.) carcass that weighed 21kg was used as a model for human bodies to determine the rate of decomposition and the pattern of insect succession on decomposing bodies in Jamaica. Ants were the first arthropods to arrive at the carcass, followed by the Calliphorid, C. macellaria (Fabricius). Both adults and larvae of Cochliomyia macellaria (F.), Chrysomya rufifaces (Macquart), and Chrysomya megacephala (F.) were collected from the bait 1. Larvae of Chrysomya rufifaces (M.) showed aggressive predatory behavior against other 2nd and 3rd instar Cochliomyia macellaria (F) and Chrysomya megacephala (F.). Ambient temperature had a negative effect on the developmental rate of C. rufifaces larvae and the rate of carcass decomposition. The carcass reached the dry stage by day 5 and the decomposition was completed by day 13. Most larvae were burned or desiccated on day 3. Maggot mass sustain temperatures of 14 oC above ambient temperatures over a three-day period during which had a negative impact on the duration and size of C. rufifaces larvae. Phase 2 of the study used two bait types: bait 2 (fresh goat head) and bait 3 (fresh tilapia fish). Larvae collected and reared from bait 2 produced Chrysomya megacephala and Lucilia lucigerens. Eggs collected from bait 3 were reared which produced only adult C. megacephala. The relative distribution of species was different in July, 2007, than in February, 2008. Chrysomya megacephala (F.) was the only common species collected for both phases. The species Lucilia lucigerens (James) is the only indigenous species collected during the phase 2 study in February, 2008. Larvae of C. megacephala and L. lucigerens emerged as adults in eight plus and sixteen plus days, respectively, at an average ambient temperature of 26 oC and 63 % relative humidity.