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Ground beetles (Coleoptera: Carabidae) captured in pitfall traps were compared within and among three Ecological Land Types in the Green Mountain National Forest, Vermont, to determine if beetle distributions can be linked to an ecological classification system designed to reflect biological diversity. Beetles were sampled in a nested‐scale design comprising three ecological land types, three polygons representing each ecological land type, five sites within each polygon, and six individual traps at each site. A nested analysis of variance showed only 2 of 35 species to vary significantly in relative abundance across ecological land types; most of the significant effects were at the site scale. To determine whether sites might sort into groups based on their beetle assemblages, sites were ordinated by detrended correspondence analysis and classified by two‐way indicator species analysis. Ordinations suggested that the distribution of ground beetles was somewhat influenced by site moisture; classification separated groups of hygrophilous species and wet sites from other ecologically uninterpretable species assemblages and site‐groups. Several of the site‐groups contained sites affiliated primarily with one ecological land type. However, a nested analysis of variance using the relative abundance of each of the species assemblages again showed most significant effects to be at the site scale. Results indicated that ground beetle distributions were not significantly linked with ecological land types and that the ground beetle fauna of the mid‐elevation forests of the western Green Mountains is comprised mainly of forest generalists, with some specialist species responding to a moisture gradient at the site scale. Because the ecological land type units did not explain distributions of carabids, these organisms should next be related to higher and lower scales within the classification system. Distributions of other invertebrate and vertebrate species should also be studied to test the utility of this ecological classification system for monitoring forest biodiversity.

We studied breeding dispersal of double‐crested cormorants (Phalacrocorax auritus) associated with management practices that suppressed their reproduction on Lake Champlain in the northeastern United States. We implemented an experiment on one colony by spraying corn oil on cormorant eggs in portions of the colony and leaving other portions untreated. Gulls (Larus spp.) consumed cormorant eggs during the oiling process, but we reduced and then eliminated predation levels after the first year of the study. We used mark‐recapture techniques within the experimental framework to measure rates of breeding dispersal for cormorants from the experimental colony and an unmanaged colony in Lake Champlain. Egg oiling increased the movement rate to the unmanaged colony by 3% during the year with no egg predation by gulls. When gulls depredated cormorant eggs at high rates during egg oiling, movement to the unmanaged colony increased by 20%. When cormorants are managed to reduce population sizes, methods that limit dispersal away from the managed colony may be most effective. Such methods would mitigate effects to nontarget populations and allow for a greater portion of the metapopulation to be managed.

Lent, R A and Capen, D E 1995 Effects of small-scale habitat disturbance on the ecology of breeding birds in a Vermont (USA) hardwood forest -Ecography 18 97-108We studied territory placement and foraging behavior of breeding birds in relation to juxtaposition of forest vegetation and logged patches in southern Vermont, USA Different bird species used disturbed vegetation at differing spaual scales, depending on temtory size Four species Dendroica pensylvamca. Geothlypis trichas, Zonotrichia albicollii, Oporornis Philadelphia showed strong clumping of their smaJl (< 0 5 ha) territories m logged patches and were absent or rare in undisturbed forest Eleven species (e g Seiurus aurocapillus, Vireo ohvaceus) tended to avoid logged areas, especially the centers of cut patches An additional 17 species fell between these two extremes, using a mixture of dismrbed and undismrbed forest and showing no tendency to prefer one or the other These 17 species tended to have larger (1 to > 3 ha) territories than disturbance specialists We used ordination and quantitative matnx compansons to describe and test relationships among 14 of the most common bird species according to their similanties in temtory habitat structure, tree species composition, and foraging behavior These analyses did not reveal any strong associations between foraging behavior and use of cut versus uncut forest Habitat use by birds occupying this forest mosaic, with its strong local gradient of vegetation structure, was thus not associated with concurrent vanation in foraging behavior The sizes of cut patches of forest (0 7-1 6 ha) in our study area may be close to the minimum required to attract distinct breeding assemblages of non-forest birds to otherwise undisturbed forest ecosystems Bird species that use patches of early-successional vegetation embedded m a forested landscape may adopt a fugitive strategy as they seek nesting habitats in the spnng Careful use of forest management techniques may permit both forest-intenor and early-successional bird species to coexist in the landscape R A Lent and D E Capen, Univ of Vermont, School of Natural Resources, Burlington, VT 05405, USA {present address of RAL Harvard Umv ,