GROSS, MICHAEL F. Biology Program, Georgian Court College, 900 Lakewood Ave, Lakewood, NJ 08701-2697. - Vegetation characteristics of a New Jersey Pinelands community containing high terrestrial gastropod density and exotic gastropod species.
Several years ago, on a forested part of the Georgian Court College
campus in the New Jersey Pinelands, investigators found an abnormally
high density of terrestrial gastropods, including three European
gastropod species, two of which (Discus rotundatus and
Oxychilus alliarius) were not previously reported in New
Jersey. The exotic species dominated the gastropod portion of the
community. I sampled the vegetation in this community to determine if
the species diversity was similar to that of other Pinelands
communities, and if there were species of European origin with which
the snails may have arrived, as hypothesized by the investigators who
studied the gastropods. The plant community was dominated in richness
and abundance by New Jersey Pinelands species in both overstory and
understory layers. Tree species richness was relatively high for a
Pinelands community, but there were few members of tree species native
to Europe and they were small in size and number. The understory also
contained some individuals of a few species that were of European
origin. However, parts of the campus about 0.5km away contain large
numbers of 7 tree species native to Europe that were planted around
1900. The exotic snail species may have arrived with those trees and
migrated to their current location. They have come to dominate the
forest gastropods despite the mostly native composition of the forest
vegetation.
Key words: exotic species, forest, gastropods, New Jersey, Pinelands, species diversity