Complex Interrelationships Among Aboveground Biomass, Soil Chemical Properties, and Events Caused by Feral Goats and Their Eradication in a Grassland Ecosystem of an Island

Kenji Hata, Mari Kohri, Sayaka Morita, Syuntaro Hiradate, Naoki Kachi

Research output: Contribution to journalArticle

10 Citations (Scopus)


This study examined the recovery, via biotic and abiotic pathways, of a grassland ecosystem after eradication of introduced exotic goats. We used path analyses to evaluate the relative strength of relationships among aboveground biomass, soil chemical properties (carbon, nitrogen, and phosphorus content; soil acidity), presence of nesting seabirds after goat eradication, extent of vegetation degraded by goats before their eradication, plant species composition after removal of goats, and topography. Models including the same variables with different paths were constructed using the Bayesian estimation method, and the best-fit models were constructed by comparing deviance information criterion values. Results of the path analyses demonstrated that vegetation degradation and soil erosion prior to goat eradication increased soil exchangeable acidity, which resulted in limitation of aboveground biomass. Seabird nesting after goat eradication increased the quantity of soil nutrients, possibly through inputs of feces, eggshells, and dead chicks or adults. The increase in nutrients was affected indirectly, via seabird nesting, by topography and vegetation type after goat eradication. The direct and indirect relationships demonstrated by our results suggest the existence of complex interrelationships during recovery of ecosystem function after eradication of exotic mammals.

Original languageEnglish
Pages (from-to)1082-1094
Number of pages13
Issue number6
Publication statusPublished - Jan 1 2014
Externally publishedYes


All Science Journal Classification (ASJC) codes

  • Ecology, Evolution, Behavior and Systematics
  • Environmental Chemistry
  • Ecology

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