Vegetation history and dynamics in New Zealand: Future scenarios and improved trajectories towards restoring natural patterns

Abstract

New Zealand is a micro-continent that has been more isolated from mainstream (especially Northern Hemisphere) evolution than any other large, ice-free land mass. This has created a land of unusual and often unique ecology, notably lacking land mammals. Native Gondwanan elements, and others considered ancestral to major world lineages, imply some continuity back to Gondwana itself. Together, both old and new arrivals make up a largely endemic biota. These have been decimated both ecologically and socio-culturally (extinction of experience) by large numbers of recent continental imports. We examine opportunities for recovery of some of the lost integrity of natural patterns, at a range of scales, albeit in the absence of an alarmingly high number of extinct and critically endangered, keystone species. Apart from the essential pest-control programmes being carried out assiduously by Government and NGOs, our research has focused on design of landscape factors that can facilitate regeneration, recovery, and connectivity (ecologically and socio-culturally). Earlier landscape-optimising models are being combined with reserve-design theory (island-biogeography concepts) and spatial configurations based on empirical dispersal data, refined by considering the patch condition and proximity requirements of contrasting wildlife guilds. We present some preliminary data. Like the rest of the world, New Zealand is at an ecological crossroads regarding the extent to which it will retain its endemic biota and landscape legibility. We can take action even in the absence of perfect knowledge to apply the most promising strategies and restoration techniques available—or we can wait and watch the decline.