New Zealand (NZ) provides a home to some of the most interesting birdlife in the world. This is because NZ is an island, which means it has allowed for unusual evolutionary processes. Humans only arrived on the island about 800 years ago. So, birds have been able to reproduce and evolve to their surroundings without human influence and without land animals trying to eat them! Since NZ is made up of island and not attached to large landmasses, the species that evolved there are only found in NZ. This makes them all the more special and important. Native birds still hold particular significance to the Māori people (first people to inhabit NZ) due to their significance in kōrero tuku iho (legends/mythology). In this present day, many of these native birds have become extinct or are now in danger of extinction due to human arrival on the islands.
The laughing owl, now extinct, photographed some time between 1889 and 1910. Photo: Henry Charles Clare Wright, via wikipedia.com.
The Kea, a native bird of New Zealand, which is now classed as ‘vulnerable’. Photo: David Spiegel, adventurecloud.com
Humans introduced mammals on purpose and also by accident to NZ. This is one of the biggest threats to the native bird species of NZ (PCE, 2011). Ships coming from other countries brought rats by accident, the brushtail possum as well as stoats made it to the island and began to reproduce and spread. When the mammals came, the birds were unprepared, as they have been used to living their lives without these predatory mammals. It has been estimated that 60% of all kiwi chicks are eaten by stoats (PCE, 2011). The NZ government decided something must be done to stop the decline of native bird species.
The ‘Predator Free New Zealand 2050’ action plan has been put into effect, aiming to remove the three main predators (rats, possum and stoats) from NZ by 2050. The main method of doing this is to distribute a poison called sodium fluroacetate, also known as 1080, over target areas in the hope that the predators will eat the poison (PCE, 2011). Planes currently drop the poison over these areas with little or no aim. This poison is not a specific poison for these mammals; it affects almost all breathing organisms.
This is the cheapest way of controlling the pests but the numbers of native bird species are still in decline. 1080 has been able to decrease possum numbers by 99.5% in one area (Greene et.al, 2013). However, it is difficult to know how 1080 is affecting the wider ecosystem and if the deaths of non-target species outweigh the benefits of reducing the number of target species. It has been argued that the birds will be unable to recover from the significant declines in non-target species. A disturbance of this scale has the potential to decrease the endangered birds likelihood of thriving (Greene et.al. 2013).
The reality of distributing 1080 poison. Cartoon: Al Nisbet, 2008. Alexander Turnbull Library. NZ Cartoon Archive. DCDL-0007273. Via stuff.co.nz.
There are multiple questions that need to be addressed when making decisions to continue distributing 1080. It is still unknown how the poison is affecting soils, plants and nutrients. These would be classed as ‘sub-lethal’ harms, which have not yet been investigated (Weaver, 2006). Everything in the ecosystem is interconnected and so it is essential that the sub-lethal effects of 1080 be further investigated to understand how it will affect the ecosystem as a whole. In addition to this native people of New Zealand (Māori people) rely on the bush for many reasons, one being medicine from Te Rongoā plants. It is impossible to know the effects 1080 will have on these plants in the future.
The cost of distribution would almost double if 1080 was to be distributed by the land rather than by aerial drop (PCE, 2011). However, this method would allow for a reduction in non-target species death. Unfortunately, the reduced cost and the ease of distributing 1080 by aerial drop are currently outweighing the benefits of this option for the decision makers.
The points outlined in this blog aim to communicate the significant number of discrepancies found in the thinking behind distributing 1080 across NZ. It is essential to understand how 1080 is going to affect the ecosystem as a whole, which could directly affect the lives of Māori people that rely on the services such as medicine from the bush. Until the effects are fully understood, all distribution of the poison should be halted. The release of such a toxic substance with such little knowledge of the true effects is reckless and could worsen the situation it is aiming to better.
For further reading please see the following:
Socolar, S. and Wilcove, D. (2016). “Threatened Birds” Encyclopedia of Biodiversity. Second Edition addresses the wider scope of threatened bird species and so gives an overview of other issues bird communities are facing as well as ways of preventing these declines.
The New Zealand Department for Conservation webpage on 1080 poison.
1080: the facts offers some different views on the issue.
- Greene, T.C., Dilks, P.J, Westbrooke, I.M, Pryde, M.A. (2013). Monitoring selected forest bird species through aerial application of 1080 baits, Waitutu, New Zealand. New Zealand Journal of Ecology, Vol.37, No.1
- Parliamentary Commissioner for the Environment, PCE. (2011). Evaluating the use of 1080: Predators, poisons and silent forest. Parliamentary Commissioner for the Environment (Dr. Jan Wright) Report. Accessed online: www.pce.parliament.nz
- Weaver, S. (2006). Chronic Toxicity of 1080 and its Implications for Conservation Management: A New Zealand Case Study. Journal of Agricultural and Environmental Ethics, 19(4), 367-389