New Zealand needs to remedy the impact of irrigation and hydro development or lose a majority of our native freshwater fish species, 74 per cent of which are threatened and at risk of becoming extinct.
Irrigation, hydro development, fishing and introduced species have reduced the populations of native fish species such as the galaxiids, a family of fish that includes migratory whitebait.
Hot, dry summers such as the current one, and irrigation takes and storage schemes that reduce river flows are pressures these species can do without.
Research by Dr Simon Howard at University of Canterbury shows that changes in river flows due to human activities alter the specific habitat conditions which fish require for their survival. Habitat loss has contributed to the decline in native fish populations. His work focuses on the Waitaki River catchment, New Zealand’s second largest river.
The Waitaki River has been much changed by hydro development and irrigation. Dr Howard’s work shows that we need to safeguard its remaining natural character to protect our distinctive native fish such as the bignose galaxias and upland longjaw.
Irrigators want to take more water from the Waitaki for irrigation. Government’s hand-picked commissioners at Environment Canterbury have notified a change to the Waitaki River Regional Plan to facilitate this by changing the flow regime.
This is bad news for our native freshwater fish – we need to protect our rivers and their flows, not promote big new irrigation schemes to dam them as National is doing.
The Tukituki catchment in Hawke’s Bay is home to 18 threatened native freshwater fish species. Building the proposed Ruataniwha Dam in Hawke’s Bay for an irrigation reservoir will block their downstream migration, essential for many species which spend part of their life at sea.
The Department of Conservation (DoC), which is responsible for our native fish species, wanted to use the RMA submission process to highlight the scheme’s impact on native fish, but then Environment Minister Nick Smith prevented DoC from doing that.
The RMA needs stronger provisions to safeguard our native wildlife and their habitats, not the radical changes that Nick Smith is proposing. DoC needs to be properly funded to work with landowners and councils to protect their habitat, not have its funding slashed as National has done.