The Climatology of Blowfly Myiasis.

Abstract

Records of oviposition by blowflies on test groups of sheep, over a five-year period, were examined for relation between the rate of oviposition per day and the conventional meteorological indices of daily weather conditions. There was a definite correspondence with the maximum shade temperature for the day. The relation was not straight-line, the slope changing at between 18 and 20°C. The association with the minimum temperature was not significant. Insolation, as measured by the difference between maximum temperatures in the sun and shade, was positively associated with oviposition.The humidity indices—evaporating power of the air and the saturation deficit—and the ratio of the daily totals of rain and evaporation, showed a low correlation ; the rainfall correlation was barely significant. The association was in no instance statistically reliable.