Work is being carried out to find out more about Northland's at-risk īnanga population.
Work is being carried out to find out more about Northland's at-risk īnanga population.
A tiny whitebait fish barely noticeable to most in Northland is at risk of disappearing.
But a $1.2 million project is designed for Īnanga spawning habitat restoration in the region, to help the fish thrive again.
Mountains to Sea Conservation Trust (MTSCT) is scaling up its Whitebait Connection work inNorthland, locating, protecting and enhancing īnanga spawning habitat.
The Northland Īnanga Spawning Project will receive $1.2m over three years from the Ministry for the Environment's Freshwater Improvement Funding, Department of Conservation, Fonterra and Foundation North.
The project is also being supported by Ngāti Manu – Karetu Marae, Whirinaki Trust, Patuharakeke Te Iwi Trust, NZ Landcare Trust, Northland Regional Council, NorthTec, Reconnecting Northland and Hokianga Harbour Care.
The conservation status of īnanga is 'At Risk - Declining' due to habitat disturbance and modification. The available spawning habitat for this species has decreased in many places.
Whitebait was once plentiful in Northland's waterways, with this catch in Hatea River, Whangārei, in 2004. The prized delicacy can no longer be collected from many sites.
Drainage of swamps and wetlands has reduced vast areas of adult habitat, whereas land-use change on riverbanks has reduced spawning habitat. Around 97 per cent of Northland's original wetlands have been lost. The value of these habitats is now being recognised, leading to protection and restoration initiatives.
In 2013, Whitebait Connection started to focus on the importance of īnanga spawning sites in Northland.
At that time, only one īnanga spawning site had been confirmed and documented from the whole region from a 1980s DoC survey.
In 2014, Whitebait Connection partnered with NRC, Ngā Whenua Rahui and Whangārei-based hapū Patuharakeke to host a wānanga at Takahiwai, Whangārei, aimed at learning about īnanga spawning survey methodology with expert Dr Michael Hickford from the University of Canterbury.
Since then, Whitebait Connection has identified 17 īnanga spawning sites on 14 waterways in Northland and created the 'National Īnanga Spawning Programme' in 2015 which shared the knowledge even further.
The programme has since involved thousands of people around NZ and helped to identify and protect nearly 100 new spawning sites around the country.
Īnanga in Northland are classed as 'At Risk - Declining' due to habitat disturbance and modification.
MTSCT's Poutokomanawa/co-director freshwater lead Kim Jones said: "Our knowledge base in Northland is still not where it needs to be to ensure this species has the habitat it needs to sustain a viable population.
"The data that Whitebait Connection has collected is currently the only data the region has on the location of these critical life-stage specific habitats.
''If we do not accelerate the identification and restoration of these important areas alongside the community and partners, we risk losing a taonga species from Northland," Jones said.
"We also know that restoration for īnanga is good for water quality, biodiversity and building resilience within our waterways and communities, so it's a win for the big picture too."
The funding boost will enable capacity and capability development for the local community to help fill current knowledge gaps and increase effective management of freshwater and riparian habitats for the protection of īnanga.
Data will be used to prioritise habitat restoration that builds resilience for the effects brought on by climate change and to motivate and implement actions that will improve water quality.
Adult īnanga are the smallest of all the whitebait species, usually reaching 110mm.
Unlike the other members of the whitebait family, īnanga cannot climb. Instead, they overcome small barriers by burst swimming. These fish are a lowland species due to their lack of climbing ability. Īnanga spawning habitat is well understood compared to the other species. They spawn among riparian vegetation near the upper limit of the saltwater wedge during spring tides.
The likely impacts of climate change on īnanga are not yet fully known. The 2020 and 2021 summers brought severe droughts to Northland. Saltwater has been travelling further up waterways with these low flows, changing the location of the saltwater wedge - an environmental factor that heavily influences the suitability and location of īnanga spawning habitat on a waterway.
Communities in Northland that once ate whitebait as a way of life and mana-enhancing Manaakitanga no longer do so, due to the decline in this species and the quality of the water they reside in, Jones said.
These maps show the loss of Northland's wetlands - the prime habitat of īnanga - since human occupation began.
Whitebait fisheries in New Zealand rivers are based on the juvenile, upstream migrant phase of five species of galaxiid fish. The main species is īnanga and its proportion in whitebaiters' catches is typically 70 to 100 per cent of the total catch. Īnanga are 'At Risk – Declining' according to New Zealand's latest threat classification for fish.
Northland has 21 main catchments and an extensive network of rivers and streams. Northland's narrow landmass means most rivers are relatively short with small catchments.
