Amelia McQueen: 'Mountains to the Sea' approach needed

Dr Amelia McQueen

The Ngaruroro River, its catchments and the Clive River (the old Ngaruroro) are soon to be considered by a special tribunal for a Water Conservation Order (WCO).

A WCO recognises special features of a river system including ecological, recreational, and cultural values. Its purpose is to protect values of national significance. The ecological values of the Ngaruroro River and its catchments are wide ranging.

They include a large diversity of indigenous fish of which nine are threatened, coastal spawning grounds of inanga (whitebait), a migration passage and feeding grounds for many fish species, and breeding and feeding habitat for threatened native birds such as black-billed gull, banded dotterel and Australian bittern.

The applicants of the WCO have assessed all values of the river and taken a "Mountains to the Sea" approach, setting out to protect the values for the whole reach of the river(s). There are certainly strong ecological grounds for this approach.

The river should be considered as a whole ecosystem from the mountains to the sea, recognising the life cycle of the threatened fish that may reside in the upper to mid reaches. For example, bluegill bully, redfin bully, longfin eel and koaro all require access to the sea to complete their life cycle.

Access to the sea is not only about making sure there are no physical barriers (e.g. dams and drains). It is also about ensuring that water quality and water levels are sufficient for these fish species to not only survive but flourish. Therefore, it does not make sense to protect one part of the river and degrade another part, for example via intensive land use, water diversion and abstraction.

Carrying on with the fish theme, if the lower reaches are not included in the WCO, the culture of whitebaiting and the natural food webs associated with inanga could be undermined. It is important that inanga spawning habitat in the Ngaruroro River, Clive River and associated estuary areas are recognised and protected.

In another context, the Hawke's Bay Biodiversity Strategy which aims to halt the decline of indigenous flora and fauna has recently been gaining momentum and a Water Conservation Order that protects the ecological (as well as other) values of the Ngaruroro River and its catchments would be a perfect start to seeing this strategy been put into action - "protecting biodiversity in Hawke's Bay river ecosystems".

Dr Amelia McQueen is a senior lecturer at EIT and a member of the Te Taiao Hawke's Bay Environment Forum. Views expressed here are the writer's opinion and not the newspaper's. Email: editor@hbtoday.co.nz