An Ecological community is usually defined as an assemblage of species in a given habitat, with trophic interactions among these species represented by a static food web. Most communities, however are not isolated from the effects of species in adjacent habitats and individuals can change their position in the food web or move between habitats as they change body size. This award focuses on interactions that take place across habitat boundaries, using observations of natural populations, experimental manipulation of habitat boundaries, and experiments in artificial habitats to estimate the importance of interactions between members of stream and wooodland communities. The study focuses on resources of salamanders and on interactions among salamander populations and it tests ecological theories on the maintenance of complex life cycles and models interactions between size-structured populations as well as the role of interactions between communities in landscape ecology. The study of interactions among species at habitat boundaries is important to understanding the consequences of habitat fragmentation that results from shifting land use patterns.