KKHS students conduct eDNA sampling of the Wairoa Stream
Kerikeri High school students became forensic detectives in March this year sampling the Wairoa stream for eDNA. Just like criminals leave DNA at the site of a crime, organisms living in or alongside the Wairoa stream shed DNA into the waterway. The environmental DNA (eDNA) collected can be analysed and matched to a library of DNA to identify what organisms are present. The results from the students sampling are available for viewing at Wilderlab website:
Native species deemed to be at risk were detected including kāeo (freshwater mussels), torrent fish and tuna (long finned eels). An invasive species, Gambusia (mosquito fish) was also detected.
Based on the types of organisms detected in a waterway, scientists can give it a TICI score. This is a measure of the waterway’s health. The Wairoa stream has a TICI score of 90.81. This measure of stream health places the Wairoa stream at the lower end of acceptable. The Kerikeri river sampled by the students on the same day had a TICI score of 81.46 placing the condition of the river at the higher end of poor. The students would like to thank Kerikeri Rotary members for helping fund a number of eDNA kits.
Students would like to expand their investigation to use eDNA testing to:
Monitor the Wairoa stream over time to assess if restoration efforts are having a positive impact, with samples to be taken in 2025 and 2026.
Gain baseline data of what are living in the Dalton track stream and Te Tahawai stream, tributaries of the Wairoa stream.
Sample the Wairoa stream at intervals above the waterfall to gain base line data of this section of the stream.
They are currently working towards submitting a project proposal to obtain thirty-six kits through the Wai Tuwhera o te Taiao community science programme.
There is an opportunity for the students to partner with people in the community who would be willing to purchase additional eDNA kits to expand the project to include monitoring the Te Tahawai stream over time or extend the eDNA sampling into the three branches of the Wairoa stream beyond Riddell Road. The cost of each kit is $290; however, project partners are currently being offered a 20% discount by Wilderlab. Please contact Science teacher Sandra Leaming at Kerikeri High School if you would like to be a project partner sleaming@kerikerihigh.ac.nz
