Meteorological factors affecting beginning and end of foraging activities of Camponotus maculatus aegyptiacus emery (HYM., formicidae)

Summary

It is to be concluded that the nocturnal ant C. maculatus aegyptiacus Emery starts foraging with the sun-set and its field activities are stopped with the sun-rise. The level of foraging activity showed two peaks at 1–3 hours after evening start and before morning stop.

The differences in temperature and relative humidity at evening initiation and morning cessation of foraging activities suggest that both temperature and relative humidity have a marked effect on the evening start and morning stop of field activities.

Although the atmospheric pressure, wind velocity and dew may have affected the rate of trail activity they appeared to have, within the ranges obtained, a very slight influence upon the evening start or morning stop of foraging activity.

Cloud cover is not involved in the evening initiation or morning cessation of trail activity since it happened that the sky was almost always very clear at both evenings and mornings of all the nights of investigation from May to October but, the probability that the rate of nocturnal foraging activity of C. maculatus aegyptiacus might be affected by the cloud cover through the reduction of the moonlight exists. It is hoped to examine this in more detail at a later date.