ACCUMULATION OF CU AND NI IN SUCCESSIVE STAGES OF LYMANTRIA-DISPAR L (LYMANTRIIDAE, LEPIDOPTERA) NEAR ORE SMELTERS AT SUDBURY, ONTARIO, CANADA

The accumulation of Cu and Ni in successive life stages of the gypsy m oth (Lymantria dispar), feces, and foliage near an ore smelter at Sudb ury, Ontario and a control site was investigated. Higher concentration s of Cu and Ni were found in all larval stages collected at Sudbury th an in those from the control sire indicating that elevated levels of t hese metals in the Sudbury environment is an important factor influenc ing body burdens. These differences were associated with higher metal concentrations in the foliage of host trees from this site. However, d ifferences between sites became less significant for pupae and adult s tages. At the Sudbury site, concentrations of Cu (mu g g(-1) dry wt) d ecreased in successive instars and then increased in tissues of pupae and adults. In contrast, Cu content (mu g/individual) increased during larval development and then decreased in pupae and adults. The patter n of Ni concentration and content in larvae from the Sudbury site was similar to that of Cu. Patterns of Cu and Ni concentration and content throughout the life stages are explained by changes in weight resulti ng in a dilution effect in early stages, and a concentrating effect in later stages. Differences in Cu and Ni concentration and content betw een Sudbury and control populations became less significant following the pupal stage suggesting metal elimination with the exuviae and meco nium. This study also illustrates the importance of sampling all stage s in an insect's development when measuring accumulation of metals. Fe cal and foliar concentrations of Cu and Ni from Sudbury were not signi ficantly different suggesting that metal assimilation is low. Even tho ugh gypsy moths from Sudbury contain elevated levels of Cu and Ni, met al burdens in their tissues do not represent a significant route throu gh the food chain. However, the conversion of foliage with high metal content to feces implies that other ecosystem consequences should be i nvestigated.