Native fish, including eels and whitebait, are being rescued from the Linwood Canal to ensure their survival while a new cycleway is built.
Work on the second stage of the Rapanui - Shag Rock Cycleway along Linwood Ave between Linwood Park and Dyers Rd started in early January.
A cofferdam - an enclosure built in the water to create a dry work environment for construction - is being built in the Linwood Canal to widen the shoulder of Linwood Ave.
Water will be drained from the cofferdam leaving resident fish – likely including eels, inanga (whitebait) and common bullies - marooned if they’re not removed first.
WPS Opus Ecologist Annabelle Coates, who is carrying out the rescue mission for the Council, is unsure how many fish she will find. “We’re not expecting huge numbers because traditionally the Linwood Canal hasn’t been that diverse, however we could be surprised by the numbers and species as that's been known to happen at other locations.”
She is hopeful there could be some endangered long-finned eels living in the canal.
Ms Coates will use fyke nets to catch as many fish in the cofferdam as possible before collecting the rest using an electric fishing machine that attracts and then stuns the fish. She’ll remove them from the water in a net before releasing them in the main part of the canal. The process does not harm the fish and is deliberately being carried out outside of spawning season.
The ecologist will also be on hand when water is drained from the cofferdam in case there are any fish left behind. “The Council has an obligation to protect native fish and to maintain fish passage so this has to be done and it’s an easy thing to do to save them,” she says.
Council City Services Project Manager Adrian Thein says fish conservation is a condition of resource consent and an important part of minimising the impact of cycleway work on the local environment and ecology.
“Native fish and their spawning habitats are legally protected so we have to take care not to harm them when doing essential work around waterways. We’re always happy to do our bit to make sure the local flora and fauna is preserved.”
Last year about 26 shortfin eels were removed from a Woolston drain using a similar electric fishing method to make way for the development of the Te Oranga Waikura Urban Forest and Stormwater Basin in Linwood.
The second stage of the Rapanui Shag Rock Cycleway project is due for completion in September and the main contractor for the project is Fulton Hogan.
When the route is complete it will connect the central city and Sumner via the Christchurch Coastal Pathway and Linwood.
The central city end of the route between Fitzgerald Avenue and Linwood Park opened in December.