No Park Is an Island: Increase in Interference from Outside as Park Size Decreases

  • Daniel H. Janzen


There is evident conservation value to numerous small habitat preserves (parks) when large protected areas are impractical (Simberloff 1982). However, such a management policy brings to mind a caution that is often unappreciated for parks and other forms of conserved pristine vegetation, and becomes ever more appropriate as park size decreases. The smaller the patch (island) of habitat that is viewed as pristine, the greater the effect of the surrounding secondary successional vegetation and croplands as a source of 1) animals and seeds that enter the park and interact with the residents, and 2) food subsidy for residents capable of foraging outside of the pristine forest.


Secondary Succession Seed Rain Tree Fall Seed Shadow Pristine Forest 
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© Oikos 1983

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  • Daniel H. Janzen

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