Researchers have filmed previously unseen marine communities off the Fiordland coast, including a protected species of red coral in unprecedented numbers.

Te Herenga Waka—Victoria University of Wellington Professor James Bell said they were filming at depths of 80 to 130 metres when they found the new marine communities.

"The most incredible find was about 4 kilometres north of Doubtful Sound/Patea."

CLICK HERE to watch video footage.

"On the ocean floor, we saw forests of bright red coral.”

The coral species, Errina novaezelandiae, is a hydrocoral, not a true coral.

The discovery was made during a project aboard the Department of Conservation (DOC) vessel Southern Winds.

“We’ve been exploring these deep reefs in Fiordland for many years, but we’re rarely able to work on the open coast outside the fiords because of the weather."

"On our most recent trip in January, the weather was finally on our side,” Bell said.

Using a remotely operated vehicle (ROV), the team captured video footage of reefs at depths greater than 100 metres.

Red corals, typically found in sheltered fiord conditions, were seen in massive numbers on the open coast.

Video footage revealed numerous red corals alongside larger black corals, both protected under the Wildlife Act.

These coral forests are crucial for maintaining habitat diversity, supporting various fish and crayfish species.

The research was supported by the George Mason Charitable Trust and DOC's conservation services programme, with logistical support from DOC.