Stage mortality rates of Lucilia sericata (Diptera: Calliphoridae)

Lucilia sericata (Diptera: Calliphoridae) biology has widespread implications in forensic science. Transferring maggots from a crime scene to a laboratory for rearing has been noted to cause growth delays. A previous experiment that explored this delay found that maggot mortality was higher in certain stages than in others. The purpose of this experiment was to determine if the mortality observed was due to background mortality, i.e. mortality that occurs due to the chances of mortality occurring naturally within the populations. The results of this experiment will help to determine if the high mortality noted in the first experiment was due to background mortality or due to mortality from transfer.

Experimental units were placed in Tritech Research Chambers set at 15.0 ºC, 25.0 ºC, and 35.0 ºC with Light:Dark cycles of 16:8. There were four treatments and controls, each with four replications. Sampling times were based on temperature: 15 ºC (65 hours, 115 hours, 225 hours, and 485 hours); 25 ºC (30 hours, 50 hours, 112 hours, and 275 hours); and 35 ºC (30 hours, 50 hours, 112 hours, and 275 hours). Maggots were counted and the mortality rates were recorded for each larval stage.  

Mortality patterns were similar across each temperature. Lower survivorship was noted in the first stage, with more noted in the second and third stages. The largest decrease in survivorship was noted between third and adult stages.