Feral sheep on Socorro Island: facilitators of alien plant colonization and ecosystem decay

@article{Walter2007FeralSO,
  title={Feral sheep on Socorro Island: facilitators of alien plant colonization and ecosystem decay},
  author={Hartmut S. Walter and Geoffrey A. Levin},
  journal={Diversity and Distributions},
  year={2007},
  volume={14}
}
The paper examines the role of feral sheep (Ovis aries) in facilitating the naturalization of alien plants and degrading a formerly robust and stable ecosystem of Socorro, an isolated oceanic island in the Mexican Pacific Ocean. Approximately half of the island is still sheep‐free. The other half has been widely overgrazed and transformed into savannah and prairie‐like open habitats that exhibit sheet and gully erosion and are covered by a mix of native and alien invasive vegetation today… 
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