Abstract

Introduced rats (Rattus spp.) can affect island vegetation structure and ecosystem functioning, both directly and indirectly (through the reduction of seabird populations). The extent to which structure and function of islands where rats have been eradicated will converge on uninvaded islands remains unclear. We compared three groups of islands in New Zealand: islands never invaded by rats, islands with rats, and islands on which rats have been controlled. Differences between island groups in soil and leaf chemistry and leaf production were largely explained by burrow densities. Community structure of woody seedlings differed by rat history and burrow density. Plots on islands with high seabird densities had the most non-native plant species. Since most impacts of rats were mediated through seabird density, the removal of rats without seabird recolonization is unlikely to result in a reversal of these processes. Even if seabirds return, a novel plant community may emerge.

Keywords

Invasive plants; Rat eradication; Restoration; Seabird density; Soil characteristics; Woody seedlings

Published in

Biological Invasions
2009, Volume: 11, number: 7, pages: 1671-1688

SLU Authors

• Wardle, David

  • Department of Forest Vegetation Ecology, Swedish University of Agricultural Sciences
    
  • Landcare Research

UKÄ Subject classification

Environmental Sciences related to Agriculture and Land-use


Publication identifier

DOI: https://doi.org/10.1007/s10530-008-9396-x

Permanent link to this page (URI)

https://res.slu.se/id/publ/27536