Auckland iwi taking drastic action to reverse effects of dredging by reintroducing mussels

For a century, Auckland iwi have watched the Hauraki Gulf/Tīkapa Moana lose many of its taonga, all because humans have taken far too much to eat.

Now they've taken drastic action to reverse the effects of dredging by returning the humble mussel to the moana.

Mervyn Kerehoma has lived his entire life in the Auckland suburb of Ōrākei and knows this moana like the back of his hand

"The mussels back in the 80s used to hang off the piles over there," Kerehoma tells Newshub.

"The older cousins would come out here and try and get a kai. All us younger ones would try and follow them."

But over the years, he's seen aqualife die out and the ocean - his childhood playground - become a health hazard.

"It was really impactful on us when you couldn't smell the salt because we used to be able to smell the saltwater from our homes," he says. 

The Hauraki Gulf used to have 500 square kilometres of mussel beds but over the last century, it was all dredged out for human consumption.

"They were nursery habits for fish," Revive our Gulf programme director Peter Miles tells Newshub.

"They massively filtered the water and so we're trying to work out how to bring them back."

The Revive our Gulf project is reintroducing about 60 tonnes of mussels back into the area.

The mussels are dropped into the ocean, where overnight they'll clump together and begin to clean the water again. 

A single mussel can filter up to a bathtub worth of seawater in a day, so 60 tonnes of mussel, well that's a lot of bathtubs.

But there's an added challenge.

"So the Hauraki Gulf has a lot of sediment that's been washing through the waterways for the last 80 years," Miles says.

"So if we're going to bring back the mussel beds, we have to work out how to deal with sediment."

But Miles is hopeful that sea life will return to Okahu Bay within a year and restore it to what it was for tupuna - the ancestors of Ngāti Whātua Ōrākei.

"Our best foot forward for the food cupboard that they were brought up in, is our gift to the mokopuna of years to come," Kerehoma tells Newshub. 

Hopefully, it revitalises a jewel of his childhood to leave behind.

Watch the full story above.