Sammanfattning

New Zealand's offshore and outlying islands have long been a focus of conservation biology as sites of local endemism and as last refuges for many species. During the c. 730 years since New Zealand has been settled by people, mammalian predators have invaded many islands and caused local and global extinctions. New Zealand has led international efforts in island restoration. By the late 1980s, translocations of threatened birds to predator-free islands were well under way to safeguard against extinction. Non-native herbivores and predators, such as goats and cats, had been eradicated from some islands. A significant development in island restoration in the mid-1980s was the eradication of rats from small forested islands. This eradication technology has been refined and currently at least 65 islands, including large and remote Campbell (11216 ha) and Raoul (2938 ha) Islands, have been successfully cleared of rats.Many of New Zealand's offshore islands, especially those without predatory mammals, are home to large numbers of breeding seabirds. Seabirds influence ecosystem processes on islands by enhancing soil fertility and through soil disturbance by burrowing. Predators, especially rats, alter ecosystem processes and cause population reductions or extinctions of native animals and plants. Islands have been promoted as touchstones of a primaeval New Zealand, but we are now increasingly aware that most islands have been substantially modified since human settlement of New Zealand. Archaeological and palaeoecological investigations, together with the acknowledgement that many islands have been important mahinga kai (sources of food) for Maori, have all led to a better understanding of how people have modified these islands. Restoration technology may have vaulted ahead of our ability to predict the ecosystem consequences of its application on islands. However, research is now being directed to help make better decisions about restoration and management of islands, decisions that take account of island history and key drivers of island ecosystem functioning.

Nyckelord

behavioural ecology; biological invasion; ecosystem function; eradication; flora; matauranga Maori; nitrogen; pollen; phosphorus; rat; seabird; shearwater; succession; translocation

Publicerad i

New Zealand Journal of Ecology
2010, Volym: 34, nummer: 1, sidor: 115-136
Utgivare: NEW ZEALAND ECOL SOC

SLU författare

• Wardle, David

  • Institutionen för skoglig vegetationsekologi, Sveriges lantbruksuniversitet
    
  • Landcare Research

Globala målen

Skydda, återställa och främja ett hållbart nyttjande av landbaserade ekosystem, hållbart bruka skogar, bekämpa ökenspridning, hejda och vrida tillbaka markförstöringen samt hejda förlusten av biologisk mångfald


UKÄ forskningsämne

Miljö- och naturvårdsvetenskap


Permanent länk till denna sida (URI)

https://res.slu.se/id/publ/60447