Pāua populations in the Marlborough region have been decimated by overfishing after a ban was placed along the Kaikōura coast, following the 2016 earthquake.
The increase in diving in the top of the South Island prompted MPI to reduce the recreational pāua limit from 10 to five per person on 12 December.
On a recent dive north of the Tory Channel, Ngāti Kuia kaitiaki and recreational pāua diver Lee Mason said he had only found one pāua after two hours of diving.
"That place was abundant, you could jump in anywhere and go down and get a feed of pāua, no problems at all [but] just with the increase of recreational as well, that's started getting harder, and harder, and harder."
Mason supports the new recreational limits but wants commercial quotas to also be dropped.
"They're talking tons - and a ton of pāua is a big pile of pāua and these guys are taking this systematically from these areas and I just cannot see how it can be sustainable."
He said the overfishing had also made it difficult for local iwi to get their customary take, forcing them to travel further out to get pāua and spend longer out in the water.
Further down the coast in Kaikōura, a full ban on pāua diving remains in place.
The November 2016 earthquake lifted the coastline up by six metres in some places, leaving thousands of pāua exposed and dehydrated, prompting the ban.
Over the past three years, the pāua stock recovery has been patchy, according to commercial diver and project manager for the pāua recovery project in Kaikōura, Jason Ruawai.
He said it would be at least another two years until stock had recovered to pre-earthquake levels.
He's disappointed it has taken so long for the recreational fishing quota in the Marlborough and Nelson regions to be reduced.
"Very sluggish and you can't help but feel a little hard done by about that, especially given the unknown reasons - we suspect there could be political reason why it took so long and that's unfortunate because fisheries management needs to be a bit more reactive."
He said recreational fisheries were large stakeholders in the industry, which may explain the lack of action before now.
But Fisheries New Zealand's team manager Allen Frazer said public consultation showed people supported the reduction.
He said that stakeholders and fishery officers had reported an increased number of recreational divers in some Marlborough areas, since the Kaikōura earthquake.
"We have seen signs of overfishing of pāua in the adjacent 'open' areas along the Canterbury, Marlborough and Nelson Coast as people shift their effort in response to the closure."
Frazer said the commercial catch had already been reduced by 60 percent since the earthquake, and the new recreational limits would also help to address depleted stock.
A scientific assessment of the health of pāua stocks in Marlborough will begin in June this year.