Despite the wealth of knowledge available on the ecology, biology and physiology of the Ectemnorhinus group of weevils, little is known about the determinants of their activity patterns. Here we investigated the relationship between the activity of Bothrometopus brevis (C.O. Waterhouse) and wind direction and strength, precipitation, cloud cover, temperature, relative humidity, and habitat moisture status, on Heard Island. B. brevis was most active during warm, north-wind and light rain conditions or when it was not raining, but its habitat was wet. During heavy precipitation, activity was low, and it was negligible during cold, south-wind conditions, especially during rain or snow. There was a clear relationship between activity and early frontal conditions, which also appears to be consistent across weevil species on Heard and Marion islands. The importance of frontal rain for activity suggests that any change to frontal movement across the islands might have pronounced impacts on weevil activity.