We had a great conversation with Amy Gault, the Freshwater and Community Science Lead at Wilderlab Ltd based in Wellington, about how environmental DNA (eDNA) technology works and how it can help kiwi farmers.
Wilderlab has developed a new technology called eDNA that can pick up different types of DNA in the environment, which can help in understanding what has been living there. This technology has been used for monitoring the biodiversity of ecosystems, biosecurity, and conservation.
Amy explains that all living things shed DNA into their environment as they move around in their everyday life. By filtering out the DNA from soil, water, and even air, and sequencing it through testing, Wilderlab can gain insights into what has been living there, allowing for a more holistic understanding of the ecosystem.
"Any living thing will shed different types of DNA into its environment. We can filter it out water, soil, or sometimes even air. We're able to then get an insight into what's actually been living there and get a bit of a more holistic picture as to what the ecosystem is doing."
The technology has been put to use in a collaborative project being led by Tomorrow Farm, a dairy farm in the Upper Manawatu region. The project is funded by the Land and Waters Rural Professionals Fund and involves the Te Kāuru Hapū Collective and tie water contracting, with support from ag research.
For the past five years, the project has been conducting water quality testing and planting riparian vegetation in the upper Manawatu. The nine-month funding round is coming to an end, and the project has been pairing traditional water quality testing with cultural health monitoring and eDNA testing.
The project aims to understand how the water quality is changing from a pristine section in the upper Manawatu, which is culturally significant, and how it moves through the landscape and eventually reaches the Meryl Farm, which is still in the upper headwaters and remains beautiful. The team hopes to gain insight into what is going on in the area, what is living there, and what this can tell us about the practices in the region.
One of the key advantages of the eDNA testing is its ability to uncover previously undetected inhabitants. The technology can detect rare populations or low densities of species, which can be tricky to find through traditional visual survey methods. It is also useful for identifying different types of micronutrients that are difficult to find with the naked eye.
The collaborative project hopes to weave together all the information collected from traditional water quality testing, cultural health monitoring, and eDNA testing to gain a more comprehensive understanding of the ecosystem and how it is changing over time. With this information, the team hopes to identify potential areas for improvement and conservation efforts in the region.
With eDNA able to identify the organisms that inhabit a stream or waterway, this means farmers can quickly and easily assess the biodiversity in the water, including species of fish, plants and other animals, and make decisions based on the results.
Gault says the technology can be viewed as another piece of the puzzle, working alongside other measures such as nitrate and water clarity. It provides farmers with an integrated picture of the health of their waterways and how the land management changes are affecting it. The technology can track tangible improvements or declines in stream health and give farmers a score that ranks their stream's health compared to other streams in the country.
The project is being run by the University of Waikato and supported by a government grant. The university has also developed a stream health index, which they call the "ticky index", to rank the health of waterways around New Zealand. The index takes into account information across the tree of life, from the soil to macro-invertebrates, fish, algae, and birds. The index allows farmers to track tangible shifts as they occur and helps detect invasive species before they become a real problem.
The eDNA technology has also been recognised by the biosecurity sector as an important tool to improve biosecurity. It can help detect invasive pests and species at very low abundance, meaning that they can be identified and addressed before they cause real damage. The technology has received recognition, including a biosecurity award, for its contribution to improving the biosecurity sector.
The project has generated a lot of interest from school children, who are being encouraged to get involved. It is seen as a way to engage young people with environmental issues and to give them a sense of ownership over their local streams and waterways.
Listen to the full conversation above.