3 April 2012 Animal pests are destroying New Zealand’s biodiversity

Each day stoats kill an average of 40 North Island brown kiwi chicks. and possums destroy forests and reduce native birdlife numbers.

Cheri van Schravendijk (Te Ati Haunui-a-Papārangi, Ngāti Apa) is working tangata whenua representatives to identify effective biological agents (toxins) from native plants in New Zealand that can be used against introduced mammals. This is part of her doctoral studies as an external student at Lincoln University.

“As a result of exotic animal liberations over the last hundred and fifty years Aotearoa/New Zealand has been left on the brink of significant negative ecological change,” said Cheri.

“Scientific research into the control of these animals has progressed since then but this has often operated in isolation from the communities directly affected by the decisions being made by pest managers.

“Our kaumatua have long understood that tangata whenua have something unique to offer to research and my project is a working example of that.”

Cheri is working primarily with kamatua from Tuhoe who have knowledge (Matauranga) about native plants to identify poisonous plants that could be used to assist in the management and control of animal pests.

“I get really passionate with the ideas around providing greater participation of our people in research which, in turn, provides a broader horizon of opportunities for everyone to participate,” said Cheri.

Using criteria set by a tangata whenua advisory roopu – Ngā Matapopore – Cheri undertook an extensive review of native plants that resulted in the selection of tutin, a highly toxic compound found in the ‘loco weed’, tutu as a potential toxic agent.

Tutu is the a common name of Mäori origin for plants in the genus Coriaria that are native to New Zealand.

Currently, Cheri is assessing the potential of tutin as a new rat and possum toxin.

“Any potential new toxin should ideally have a low secondary poisoning risk, particularly for native wildlife, breakdown quickly in the environment, have an antidote, be humane in use and, importantly, be accepted by the local community,” she said.

Cheri had no intention of being a scientist before she went to university.

“I wanted to be either a teacher or a cop! But I have a strong interest in environmental science and a strong connection to the resilience of the relationship between the environment and people. This became even more important to me since I’ve had my children and thought about the legacy I would be leaving for them,” said Cheri.

Cheri says that science itself is a way (a tool) for exploring those connections at a more refined/detailed level which can then assist local communities in their decision making around the management of their natural resources.

“ I’ve found science to be an interesting ‘filter’ to look at the natural world through. It offers another perspective for our people to consider, and when coupled with matauranga Maori, can be a very empowering form of information collection and evaluation.”

Cheri’s study is supervised by Dr Shaun Ogilvie, Director of Eco Research Associates Ltd, Dr James Ross and Professor Charles Eason from the Centre for Wildlife Management and Conservation at Lincoln University.