Studies of the Responses of the Female Aëdes Mosquito. Part IV. Field Experiments on Canadian Species

Abstract

1. The responses of adult mosquitos, consisting of several Canadian species of Aëdes, were investigated under field conditions by employing heated and clothed robots.2. Moisture increased the attractiveness of a warm body two to four times when the air temperature exceeded 60°F. ; at cooler temperatures, surface moisture decreased the attractiveness.3. Warmth increased the attractiveness of a body, so that a robot at 98°F. attracted three times as many mosquitos as one at 50–65°F.4. It may therefore be concluded that moisture is the major attractant factor when the air temperature exceeds 60°F., and warmth when the temperature is less than 60°F.5. Carbon dioxide vapour emitted from an artificial head almost doubles the attractiveness of a warm body.6. The vapours of ether and gasoline were significantly attractive. A sweat-soaked jerkin was more attractive than a water-soaked one.7. Light colours were less attractive than dark ones, and luminescent dyes decreased the attractiveness of cloths. Green is less attractive than red or blue.8. Glossy satins were less attractive than matt broadcloths. Greenish-khaki nylon cloth was much less attractive than khaki drill or cotton.9. There was no evidence of interspecific differences in the responses of the mosquitos investigated.