David Towns, the author of Ahuahu: A Conservation Journey in Aotearoa New Zealand, is highly respected as a pioneer conservation biologist in New Zealand.
The Mercury Islands, a group of seven islands located 8km off the coast of the Coromandel Peninsula, which he first visited in 1971, are the main characters in his book. But he also provides many examples of other islands around New Zealand where mammalian predators were successfully eradicated, and the subsequent ecological restoration.
Each of the Mercury islands required a different approach which was arrived at in consultation with the Department of Conservation and local iwi such as Ngati Hei,
Ahuahu, the largest of the group, is the only one which is privately owned and partly farmed. In 2014 Fay and Richwhite, the owners, partnered with the Department of Conservation to eradicate kiore, ship rats and cats. When Ahuahu was declared pest free in 2016, all of the group were finally free from mammalian predators. It had taken 40 years to achieve this milestone.
Now they are once again providing a safe haven for native plants and animals. Birds such as korimako (bellbird), kākā, kererū (wood pigeon), pāteke (brown teal) and kākāriki have rapidly increased in numbers. Tuatara was saved from extinction. Rare lizards and invertebrates have been brought back. And seabirds can safely nest there.
Part One of his book is largely about conservation biology i.e. “The interlinked components of the science behind island restoration, the way seabirds and history have shaped island ecosystems, and the way technological development and understanding have made restoration possible.”
However, when endeavouring to achieve a predator-free island or sanctuary, opposition was encountered in different parts of New Zealand for a variety of reasons. It became obvious that the eradication of mammalian predators is not just about science. A community’s social, cultural and political views also needed to be taken into account. This necessitated applying a new sub-discipline: conservation socio-ecology.
For instance, on Hauturu (Little Barrier Island) objectors included an animal-rights NGO, Friends of the Earth, concerned about the non-target effects of rat baits. Their objections were resolved when an evidence-based approach in which they were invited to participate was used.
A process also needed to be worked through with local iwi which included addressing historic grievances and inequities. This took a considerable time to resolve but eventually there was a harmonious outcome.
The successful eradication of mammalian predators from more than 100 NZ islands sparked enthusiasm for creating fully fenced urban sanctuaries like Zealandia.
When these succeeded a bold vision for a Predator-Free NZ by 2050 was adopted which ambitiously aims to eradicate mustelids (stoats, ferrets and weasels), rats (Norway, ship, and kiore) and possums from all of New Zealand by 2050.
But can such a bold plan of making New Zealand predator-free really be achieved? This is a question I often ask myself. David Towns remains hopeful as innovative ground-breaking science, and new technologies are constantly being developed which should allow good progress to be made.
The Western perspective, which the early settlers brought with them, that nature was theirs to dominate and exploit has also gradually evolved to one more closely aligned with the Māori worldview, i.e. that humans and nature are interconnected, so it demands our care and respect. This bodes well for raising community enthusiasm and support for a Predator-Free NZ.
Ahuahu is aimed at those who are already deeply involved in conservation initiatives. At over 300 pages it is a long but very rewarding read.
I am privileged to be a volunteer guide on Tiritiri Matangi Island which David Towns sees as a model of community-led restoration. And I am also part of a small group endeavouring to make a precious remnant of native bush on Auckland’s North Shore predator-free. His scholarly account greatly broadened my horizons and deepened my understanding of the complexities which were involved in creating predator-free islands and urban sanctuaries in other parts of New Zealand and their subsequent ecological restoration.
I think Ahuahu would also be an invaluable resource for those who belong to enthusiastic community groups who are keen to assist in creating a predator-free sanctuary in their neighbourhood. Reading examples of how hurdles were overcome and success was achieved through collaboration with the Department of Conservation, local government, philanthropists, and bicultural partnerships would greatly assist them in envisioning the part they could play in that journey.
Reviewer: Lyn Potter
Canterbury University Press