Scientists have discovered Kaikōura's sea bed is well on its way to full recovery after being significantly damaged in the catastrophic 7.8 magnitude earthquake in 2016.
The earthquake triggered one of the largest ever canyon flushes, a type of underwater landslide that stirs up sediment and erodes the sea floor.
Victoria University of Wellington PhD student Katie Bigham told Newshub she was "really surprised when we were out in 2020".
"Got the camera down on the sea floor and the first images we saw, there were way more animals than I was expecting to see."
That's because four years earlier, a 7.8 magnitude earthquake rocked Kaikōura, almost wiping out ecosystems in the Hikurangi Reserve's Kaikōura Canyon.
The earthquake triggered one of the biggest canyon flushing events ever recorded, at 800 metric tonnes.
"About two to four times as much sediment at that one moment as is annually introduced via rivers into New Zealand waters," said NIWA principal scientist of marine ecology Ashley Rowden.
It's similar to a landslide creating an avalanche effect.
"It moves and picks up sediment and it erodes the sea floor and also in some places it moves down through the canyon," Rowden said.
Scientists captured images that show how the seafloor looked pre-quake when life was abundant. One-year post-quake shows it decimated and most recently, in 2020, where the ecosystem is recovering.
"Quite large numbers of sea stars, sea urchins and also been large numbers of deep-sea fish in the canyon," Bigham told Newshub.
Perhaps most visible to locals, Kaikōura's popular paua fishery. After years of being off limits, it has once again reopened for limited seasons.
Scientists say it could be the volatility of the environment that has led to ecosystems' resilience.
"When one of these larger events comes through, just in the way you might vaccinate yourself against a disease, the community is prepared to respond to an event," Bidham told Newshub.
Some areas of the ecosystem could be considered fully recovered this year - underwater and out of danger.
