Chatham depths expedition unveils mysteries of the sea

This tiny lobster, only 1cm wide, has never been seen before. Photo / Niwa

A bounty of new species, including a new coral dubbed "Rasta", have been found in a deep marine biodiversity survey of seamounts on the Chatham Rise.

The coral, of the genus Narella, was given the nickname because of its long white dreadlock-like branches.

Scientists also discovered a tiny squat lobster measuring 1cm across and specimens of sea urchin commonly known as Tam O'Shanters because of their similarity to the Scottish hat.

"There are three new corals that we are confident are new species from the area," said scientist Di Tracey.

The finds were made by the National Institute of Water and Atmospheric Research (Niwa) research vessel Tangaroa on an 18-day voyage in July along the Chatham Rise, which stretches for 1000km east from near the South Island.

One area surveyed was the Shipley seamount, named for former Prime Minister Jenny Shipley, which is as big as Mt Taranaki but more than a kilometre below the surface.

Voyage leader Malcolm Clark said other sites visited included the Graveyard seamounts with names in a ghoulish theme - Morgue, Zombie, and Gothic.

Three surveys of the Graveyard region since 2001 have revealed high levels of biodiversity, and many unknown species.

They include benthic macroinvertebrates - animals without backbones larger than a millimetre long - such as corals, sponges, seastars, snails, lobsters, clams, and worms.

In the first survey, 15 per cent of the species collected were unknown in the New Zealand region, and 14 were new to science.

Six new species of lace coral were discovered in the second survey in 2006.

Seamounts - mountains under the sea - can be ecologically valuable as hotspots of biodiversity, and are often the target of commercial fishing.

But the Chatham Rise, where the fishing industry wiped out the commercial viability of the orange roughy through overfishing, is also being targeted by miners because of its multi-billion dollar phosphate resources.

Widespread Energy and Widespread Portfolios applied in August 2007 for a prospecting licence over a 3048sq km area.

They hope that 100 million tonnes of phosphorite (rock phosphate) valued at more than $50 billion can be scraped off the seabed.

Chatham Phosphate Ltd has applied for another 71,750sq km around the Widespread prospect.

- NZPA