Thousands of eels have washed up on a Canterbury farm after a storm surge on Tuesday burst through a sea wall.
Many were returned to sea, but "several thousand" have died, regional council Environment Canterbury (ECan) confirmed.
The Southbridge property's owner, Tim Sanson, told 1News the incident was "so distressing".
He's had disputes with ECan over the sea wall before.
"About a year ago we got some flooding here that blew out this bank... we've spoken to ECan, Selwyn District Council, trying to get some repairs done so that we can protect the area," he said.
READ MORE: Coastal erosion turns Canterbury property into beach
"For some reason they've sat on their hands, they've done absolutely nothing.
"Consequently, this year, we get another high tide... and one of the unfortunate things about it is the creek through my place carries a lot of eels that migrate away for breeding.
"It's just an absolute mess."
And Sanson's farm was ruined after saltwater swept over it in the surge, he added.
'Something private landowners need to address'
ECan's general manager of field operations Leigh Griffiths said "the regional council doesn't collect rates to manage coastal erosion on private land or fund repairs – it's something private landowners need to address".
"We do, however, have a dedicated staff member who works with the community to clarify and help them understand what they can do to protect their properties, such as through private stopbanks and the moving of debris."
Griffiths also said strandings are "an annual, natural phenomenon" and "all part of the heke tuna (eel migration)" at this time of year.
"In absence of a lake opening, the tuna (eels) will follow any pathway where a flow of sea water is present.
"Depending on the tidal flow and beach profile, they unfortunately can find themselves stranded and perish."
ECan staff worked alongside Sanson and Selwyn District Council to help rescue the stranded eels.