ABSTRACT
Acknowledgment .................................................................................................. 100 References ............................................................................................................. 100
Research into exotic species invasions has focused on both the life-history traits of the invaders and the site qualities that may make ecosystems prone to invasion. Successful invasion of an ecosystem is typically a result of conducive combinations of species and site characteristics (Alpert et al. 2000). Crull’s Island, PA, aggressively colonized by two invasive species following the construction of an upstream dam, illustrates this interaction well. The island is used as a case study to highlight the dynamics of a highly invasible system. The process of invasion is discussed within the context of resiliency theory. Originally posited for ecological systems (Holling 1973), resiliency theory has been extended to address linked ecological and social systems (e.g., Carpenter et al. 2005; Walker et al. 2002). Although a few studies have applied the framework of resiliency theory to investigations of exotic species (e.g., Forys and Allen 2002), little has been done regarding invasive plants. Our examination of Crull’s Island highlights the
many dilemmas associated with natural area management in the eastern United States, where extensive human modification of landscape processes has combined with introduction of nonnative species to fundamentally alter the functioning of the region’s ecosystems.
