Opinion: Greater Wellington helping fish migrate and spawn by mapping barriers in waterways

Penny Gaylor.

Weekly column by Kāpiti's Greater Wellington Regional Council representative Penny Gaylor.

Greater Wellington is working with landowners to identify fish passage barriers in Kāpiti Coast waterways, a programme that connects to larger initiative with local iwi, catchment experts and students to ensure our native freshwater fish can migrate and spawn.

In our region, there are around 20 native freshwater fish species living in our streams, rivers and connected pipes. Most of these fish need to migrate to and from the sea, however barriers in waterways are stopping fish from accessing suitable habitat, resources and completing their lifecycles.

As noted by GWRC's senior biodiversity adviser, Katrina Smith, the main issue facing fish passage is poorly designed, installed and maintained man-made structures such as weirs, culverts, fords, and dams. Katrina says that these fish passage barriers pose a significant threat to native freshwater fish species, 72 per cent of which are already threatened or at risk of extinction. Currently we're approaching landowners on the Kāpiti Coast to identify and assess barriers to the passage of fish, so a plan can be established to fix any structures that might threaten our native taonga. This project will involve trained staff gaining access to a range of waterways in the Kāpiti Coast to collect data on instream structures to determine if they present a barrier to fish passage.

Our environmental science senior adviser and project manager, Penny Fairbrother, says this is an exciting project where GWRC will partner with Ngāti Toa Rangatira, Te Ātiawa ki Whakarongotai and Ngā Hapū o Ōtaki.

"A student from Victoria University of Wellington will be employed to lead the fish passage assessments and data collection, with members from each iwi providing fieldwork support in their respective areas across a range of waterways in the Kāpiti Coast."

Information collected on fish passage is logged into a national database created by Niwa that captures data on instream structures and assesses their likelihood of being a barrier to fish passage.

Penny says that at this information-gathering stage we're just trying to understand what and where the barriers are, there is no immediate requirement for landowners to fix these issues.

In the future, this information will help us to prioritise work with landowners to fix any barriers that threaten fish passage on the Kāpiti Coast.

As the Kāpiti Coast councillor, and the chairwoman of GWRC's environment committee, I'm really proud that this project is a leading example of council working closely with mana whenua for positive environmental and water outcomes.

The environmental data collected from this project is vital to establishing a holistic picture of our native species' health, providing us invaluable insights to creating a consistent, national approach to protecting and restoring our environment.

During my time as a councillor on GWRC I've been involved in lots of conversations where the old approaches to fish passage are being challenged, and so to help everyone we need to gather sound information to help us make good decisions.