CHRYSOLINA QUADRIGEMINA (COLEOPTERA: CHRYSOMELIDAE) INTRODUCED FROM CALIFORNIA TO BRITISH COLUMBIA AGAINST THE WEED HYPERICUM PERFORATUM: COMPARISON OF BEHAVIOUR, PHYSIOLOGY, AND COLOUR IN ASSOCIATION WITH POST-COLONIZATION ADAPTATION

Abstract

AbstractAdults of Chrysolina quadrigemina (Suffr.) from Westbank, British Columbia, were compared with those from Lotus, California, for differences in behaviour, physiology, and colour in association with adaptation to the long, cold winters at the former location. It was found that the Westbank beetles tend to seek shelter more readily from freezing temperatures than do those from California. They also lay more eggs, as measured during 41/2 months of their oviposition period. Most eggs from both populations probably hatch in spring. The proportion of bronze beetles in the total population correlated with high mean and mean minimum temperatures in the coldest months of the year at 11 collection areas in France, Australia, U.S.A., and Canada.