Temperature-dependent functional response of Spalangia cameroni (Hymenoptera: Pteromalidae), a parasitoid of Stomoxys calcitrans (Diptera: Muscidae)
The effects of host density, temperature and burial depth of fly pupae on the functional response of adult female Spalangia cameroni Perkins parasitizing Stomoxys calcitrans (L.) will be evaluated at five constant temperatures (15, 20, 25, 30 and 35°C), six host densities (2, 4, 8, 16, 32, and 64 fly pupae/container) and three burial depths (0, 8, and 15 cm). Though all experimental results are not yet available, we expect that they will demonstrate that the functional response of S. cameroni is a type II, at least in the top layer (burial depth 0 cm), with the maximum rate of parasitism achieved when host density is between 32 and 64 fly pupae, ranging from lowest at 15 °C to highest at 25 °C or 30 °C. The searching efficiency (a) is expected to be lowest at 15 °C, while the handling time (Th) is likely to decrease with increasing temperatures. The effect of burial depth is expected to affect the maximum level of parasitism by lowering the number of pupae parasitized with depth. We expect searching efficiency to decline with depth whereas handling time will be unaffected. Data from the experiments will be used in a simulation model aimed for development of optimal control strategies against stable flies based on inundative releases of S. cameroni.
