Overwintering and Spring Emergence of Three Coccinellid Species in the Coastal Plain of South Carolina

Abstract

Overwintering sites and spring emergence periods of three commonly occurring coccinellids were studied from 1984 to 1989 in the upper coastal plain area of South Carolina. In addition, experiments were conducted to determine the influence of temperature and photoperiod upon the feeding activity of overwintering Hippodamia convergens (Guerin-Meneville) when removed from hibernation sites. Feeding activity began shortly after removal from hibernation, increased with increasing temperatures and continued during both the photoperiod and the scotoperiod. Broomsedge, Andropogon virginicum L., was found to be an important overwintering site for H. convergens. Coleomegilla maculata (De Geer) and Coccinella septempunctata L. often shared the same overwintering habitat. Spring emergence of all three species was found to be controlled by temperature and all species began emergence at ≈50DD accumulated degree-days, with the emergence period extending from about the first week of March to the middle of April. A tendency for directional flight upon emergence was shown by all three species, with significantly more H. convergens and C. septempunctata flying to the east and south sides of the emergence cages, which was with the prevailing winds during the emergence period.