Progress toward understanding the ecological impacts of nonnative species

  title={Progress toward understanding the ecological impacts of nonnative species},
  author={Anthony Ricciardi and Martha F. Hoopes and Michael P. Marchetti and Julie L. Lockwood},
  journal={Ecological Monographs},
A predictive understanding of the ecological impacts of nonnative species has been slow to develop, owing largely to an apparent dearth of clearly defined hypotheses and the lack of a broad theoretical framework. The context dependency of impact has fueled the perception that meaningful generalizations are nonexistent. Here, we identified and reviewed 19 testable hypotheses that explain temporal and spatial variation in impact. Despite poor validation of most hypotheses to date, evidence… 

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