9318060 Palmer Theoretical studies have argued that the spatial and temporal arrangement of habitat patches may have a strong influence on population size and persistence in environments that are heterogeneous and/or disturbed. Few experimental studies have addressed the interactive effects of spatial arrangement and patch age on local population dynamics. In this research, the PI's will conduct a set of experiments to determine how the distance between patches and patch age influence the abundances and distributions of patch-dwelling organisms. The test organisms will be stream invertebrates within experimental patches of woody/leafy debris. First, the PI's will determine the spatial scale over which fauna potentially can respond to patch arrangement by measuring species-specific dispersal distances in the field. Next, experiments will be designed to manipulate the distance among patches and patch age, followed by monitoring species responses based on population abundance and distribution. %%% This research is broadly relevant to both theoretical and empirical investigations of patch dynamics and it is of particular interest to lotic ecologists because it addresses how habitat heterogeneity and faunal dispersal in streams interact to ensure population persistence in highly variable environments. in addition, this work will provide one of the first empirical applications of theoretical models which suggest using dispersal ability as a scaling function when studying spatial habitat heterogeneity.
