For many years the waters of Lake Ōmāpere, north of Kaikohe, and its only outlet the Utakura River, were too polluted for locals to eat fish from or to swim in. Today, however, the water quality has improved considerably. Whānau are slowly making their way back into the waters – and tuna (eel) is back on the marae menu again.
Wendy Henwood (Te Rarawa), a researcher with the local community environmental group Te Roopu Taiao o Utakura, is playing an important part in this recovery. The group has been researching the effects of the Utakura River’s water quality on the health and wellbeing of local people with the support of a Ngā Kanohi Kitea Community Grant from the Health Research Council of New Zealand (HRC).
As part of this HRC-funded project, the group has gathered important baseline data about current fish stocks and the relationship between the health of local Māori and the state of the river. Monitoring took place at eight specific sites from Lake Ōmāpere to the outlet of the Utakura River into the Hokianga Harbour, and a number of interviews with local whānau were recorded.
To help with gathering data on water quality, project members developed the Utakura Cultural Health Index. This method draws on components from the Cultural Health Index developed by Dr Gail Tipa and the Stream Health Monitoring and Assessment Kit (SHMAK) developed by the National Institute of Water and Atmospheric Research (NIWA) to monitor water quality.
“The Cultural Health Index and SHMAK were too complex for what we could manage as a small group with few resources, so we played around with both of those models and adapted them to form the Utakura Cultural Health Index. It’s very useful because now we have good baseline data from which to work from,” says Ms Henwood.
The Utakura Cultural Health Index method of gathering data about the health of the waterways involves observations of current environmental factors, local knowledge, testing water clarity, pH levels and temperature, and identifying and classifying invertebrates living in the waterways. A report that draws on all of the databases to summarise the research findings is currently being developed.
“Lake Ōmāpere is of great cultural, historical and environmental value to Māori. Tuna harvested from the lake and Utakura River catchment have long been an important fishery for tangata whenua. NIWA helped us establish a monitoring programme whereby data about tuna is recorded; numbers, species, weights, lengths and their health. We had some otolith bones analysed to see how old the tuna are right down the river. We found out through this survey that we have a healthy mix of ages of tuna, which is promising for the future.”
As part of the project, Te Roopu Taiao o Utakura also received support from NIWA freshwater fishery ecologists Dr Erica Williams and Dr Jacques Boubée. NIWA produced two reports for the project team, one looking at metal levels in tuna from the Lake Ōmāpere catchment and the other analysing the lake’s E.coli and nutrient levels. Both reports will provide valuable data to help Te Roopu Taiao o Utakura with future planning and decision making.
The research has meant that Te Roopu Taiao o Utakura is now recognised as a body to consult with locally about a variety of environmental-related issues. It has also helped identify two practical restoration projects to improve water quality.
“From the project and archival photographs we know that kuta1 was once plentiful – but now scarce – in the lake margins and wetlands of the catchment. We plan to fence off small selected sites to see the effects of regeneration by keeping carp away. We also plan to reinstate a section of a currently drained wetland area by planting and fencing out stock.”
Ms Henwood says the river is crucial to the wellbeing of mana whenua.
“If you don’t have a healthy environment, in particular the river – the meeting place, the ‘everything place’ for Utakura – there’s a whole lot of things that people miss out on. If you can’t get kai from the river, you have to go somewhere else. If you can’t swim in the river, you don’t do that activity any more. If you take the whole river out the picture, people’s lifestyles have to change, often to the detriment of their wellbeing.”