Is the endangered Grevy's zebra threatened by hybridization?

@article{Cordingley2009IsTE,
  title={Is the endangered Grevy's zebra threatened by hybridization?},
  author={Justine E. Cordingley and Siva R. Sundaresan and Ilya R. Fischhoff and Beth Shapiro and Jennifer A. Ruskey and Daniel I. Rubenstein},
  journal={Animal Conservation},
  year={2009},
  volume={12}
}
Hybridization between an abundant species and an endangered species is cause for concern. When such hybridization is observed, it is both urgent and necessary to assess the level of threat posed to the endangered species. We report the first evidence of natural hybridization between two equids: the endangered Grevy's zebra Equus grevyi and the abundant plains zebra Equus burchelli. Grevy's zebra now number <3000 individuals globally, and occur only in northern Kenya and Ethiopia. In recent… 

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