Mapping a forest mosaic - A comparison of vegetation and bird distributions using geographic boundary analysis

Many areas of ecological inquiry require the ability to detect and characte rize change in ecological variables across both space and time. The purpose of this study was to investigate ways in which geographic boundary analysi s techniques could be used to characterize the pattern of change over space in plant distributions in a forested wetland mosaic. With vegetation maps created using spatially constrained clustering and difference boundary deli neation, we examined similarities between the identified boundaries in plan t distributions and the occurrence of six species of songbirds. We found th at vegetation boundaries were significantly cohesive, suggesting one or mor e crisp vegetation transition zones exist in the study site. Smaller, less cohesive boundary areas also provided important information about patterns of treefall gaps and dense patches of understory within the study area. Bou ndaries for songbird abundance were not cohesive, and bird and vegetation d ifference boundaries did not show significant overlap. However, bird bounda ries did overlap significantly with vegetation cluster boundaries. Vegetati on clusters delineated using constrained clustering techniques have the pot ential to be very useful for stratifying bird abundance data collected in d ifferent sections of the study site, which could be used to improve the eff iciency of monitoring efforts for rare bird species.