New zealand-a land apart

Abstract

New Zealand is well known for its distinctive biota and high proportion of endemic taxa. A recent checklist of fossil and living plants and animals in terrestrial and marine ecosystems highlights spectacular local radiations coupled with unusual ecological niches and an amazing array of cryptic diversity across most habitats. Although New Zealand and Australia share common biotic antecedents, for the past 20 million years the New Zealand terrestrial biota has occupied constantly mesic habitats but has undergone major extinctions as climate cooled. On land, plants and animals have diversified in non-forest ecosystems, particularly shrublands and grasslands. New Zealand faces major challenges in protecting biodiversity and ecosystem services, in part because the biota is adjusting to relatively recent human occupation, and land use and marine harvesting are intensifying. Models for effective conservation in terrestrial environments are dependent on enduring predator control, legislative protection of remaining indigenous habitats and threatened species, and novel approaches that compensate land owners for contributing towards national biodiversity outcomes. Marine protected areas are minimal in extent although managed fish quota systems appear to be sustaining some species. Indigenous biodiversity in New Zealand remains vulnerable especially in ecosystems dominated by human activities. Introduction New Zealand is often compared to an Ark, laden with a unique Gondwanan biota. While this emphasises remoteness and antiquity as major drivers of our biotic distinctiveness, it less adequately captures the composite elements of the biota or the complex history of immigration, extinction and speciation, and a changing geography and climate during the Cenozoic in both marine and terrestrial ecosystems. All of these factors have contributed to the evolution of an overwhelmingly endemic idiosyncratic biota that continues to adjust to natural environmental change and more recent anthropogenic impacts.