Seasonal Abundance and Distribution of Two Forensically Important Blowflies from Genus Chrysomya in Jeddah, Saudi Arabia

The seasonal activity and abundance of two blowflies species of forensic entomology were investigated by using baited traps in four slaughterhouses at four different locations in Jeddah City, Saudi Arabia. This study were carried out from 19 February,2013 to 21 January ,2014. Three traps were fitted in each slaughterhouse. Two blowflies were attracte, Chrysomya megacephala and Crysomya marginalis. The results showed that the most abundant  in all the sites was  the C. megacephala (significant difference) than the  second type of blowflies C. marginalis, which has been caught in small quantities in four seasons.  The study showed that the peak seasonal activity of the fly C. megacephala was in the winter season with significant differences from the other seasons in the Jeddah area, where the average temperature in this season is the maximum 30.8 and minimum is 20.9 It is suitable for the spread  of this kind of flies as well as C. marginalis. It found that less season activity of these insects was the summer, where the average temperature in Jeddah was 37.2  degrees in maximum and  it was minimum 28.4 ° C and thus the climatic conditions, food and the presence of host may affect the distribution and activity of blue flies in the Jeddah area.I t  was found from the study that female attracted  traps food baits traps  more than males with significant differences, where the average was in females 91.71 and 2.49 and males 36.33 and 0.38 in the winter season, the highest rate of attraction for these insects in different seasons for each of the C. megacephala and C. marginalis, respectively. Compared with other seasons, it has also attracted the male less than females in bait traps . This is an important study to identify the activity of certain types of blue flies, which are considered of great importance in forensic medicine.