This investigation is aimed at shining a light on the state of New Zealand’s native bird populations, the challenges they face, and what it might take to restore them in large numbers back on to the mainland.
The report is structured as follows.
- Chapter 1 is an Introduction
- Chapter 2 tells the story of what has happened to New Zealand’s birds over time. It begins with showing how their evolution in isolation from the rest of the world has made them vulnerable as well as unique. A short account of the impact of the arrival of humans is followed by a description of the rise of a conservation ethic in the 20th century. The final section covers some of the developments in conservation since 1990.
- Chapter 3 is about the 168 species of native birds that still exist today. It shows which are thriving, which are in difficulty, and which are just hanging on.
- Chapter 4 explores two fundamental issues about the nature of species – the 'currency of biology'. First, dividing Nature into species is far from clear-cut. Second, it is often assumed to be self-evident that all species are equally valuable – this is discussed with reference to New Zealand’s native birds.
- Chapters 5 to 8 deal with the most critical requirements for birds to thrive on the mainland – safety from predators and suitable habitat. Chapter 5 is about the big three predators – possums, rats, and stoats. These three are the primary target of Predator Free 2050. It covers some current innovations in trapping and poisoning, and shows why the pesticide 1080 is still a vital weapon in the war against these predators.
- Chapter 6 covers other predators of native birds – mice, ferrets, weasels, hedgehogs, cats, and dogs. It finishes with a section on humans as unintentional predators – the bycatch of seabirds from fishing.
- Chapter 7 is a short description of three areas of scientific research that may lead to radically new ways of controlling, and possibly eradicating, predators.
- Chapter 8 deals with what birds need to thrive after predators have been suppressed – habitat. It describes how a number of introduced animals and plants degrade bird habitat. The last section is about protecting and restoring habitat on private land.
- Chapter 9 is about the resilience of New Zealand’s native birds in the long term. Some, like the much-loved kākāpō, are highly inbred, and others are likely to be heading that way. The four forces of evolution are explained – an understanding of these is critical for deciding whether birds should be moved from one population to another.
- Chapter 10 contains conclusions and recommendations from the Commissioner. At the end of the report, the Appendix contains a detailed list of all New Zealand’s native birds. It shows which are endemic; that is, found in no other country. It also gives the current threat classification (at a high level) of all bird taxa.
Of our 168 native bird species, just 20% are doing OK, 48% are in some trouble, and 32% are in serious trouble. Many birds are in small isolated populations – on offshore islands, in mainland sanctuaries, and in remnants of habitat – and thus at risk of inbreeding. We need sustained control of predators over large areas of habitat, so that bigger populations of birds can thrive.
Recommendations to Government are made in these areas:
- Predators – Starting a plan for Predator Free 2050
- High priority research for predator control
- Breakthrough methods for predator control using genetic science
- Habitat – somewhere for birds to live and thrive
- Bird genetics – inbreeding and restoration
- Investing in our natural heritage
- Supporting and coordinating community groups