Spatial heterogeneity of mesopredator release within an oceanic island system

Matt J. Rayner, Mark E. Hauber, Michael J. Imber, Rosalie K. Stamp, Mick N. Clout

Research output: Contribution to journalArticle


Predator-prey communities are ubiquitous in ecology, but introduced predators can drive native species to extinction within island systems, prompting the eradication of such exotics. Ecological theory predicts that elimination of top-introduced predators from islands can lead to the counterintuitive decline of native prey populations through the ecological release of smaller introduced species in a process termed "mesopredator release." We show, in accordance with mesopredator release theory and counter to conservation goals for a New Zealand island reserve, that initial eradication of cats on Little Barrier Island led to reduced breeding success of Cook's petrels, which also are vulnerable to predation by a mesopredator, the Pacific rat. The rat's impact on prey productivity varied with elevation within the island. Rat eradication was followed by a rise in petrel productivity, in support of both ecological theory and practical conservation management goals. It appears that interactions among introduced predators, native prey, and environmental gradients can drive counterintuitive and spatially heterogeneous responses to predator eradications from islands. Location-specific, ecosystem-level understanding is essential for predicting the outcomes of such restoration management techniques.

Original languageEnglish (US)
Pages (from-to)20862-20865
Number of pages4
JournalProceedings of the National Academy of Sciences of the United States of America
Issue number52
StatePublished - Dec 26 2007
Externally publishedYes


  • Cook's petrel
  • Habitat gradients
  • Introduced predator eradications
  • Island restoration
  • Trophic cascade

ASJC Scopus subject areas

  • General

Fingerprint Dive into the research topics of 'Spatial heterogeneity of mesopredator release within an oceanic island system'. Together they form a unique fingerprint.

  • Cite this