Fiordland’s depths reveal more new-to-science wonders

Scientists from NIWA and the Department of Conservation (DOC) have used a remote operated vehicle (ROV) equipped with cameras and a grappling arm to locate and sample specimens of sea pen previously unknown to science, hidden in the undiveable depths of remote Fiordland.

The sea pens (so called because of their resemblance to old-fashioned quill pens made from bird’s feathers) were discovered last month at a depth of about 80 metres in Acheron Passage, near Dusky Sound.

“We found two specimens of two different species,” says NIWA Marine Biologist and ROV operator Dr Sean Handley, “one of which is completely new to us.

“This was our second exploration of Fiordland’s deep waters in the last few years, and on both occasions we’ve discovered previously unknown fauna. We can only guess at the treasure trove of life still waiting to be discovered down there.”

Both expeditions were funded by DOC and supported by the Fiordland Marine Guardians. The goal is to better understand the biodiversity existing in Fiordland’s marine reserves at depths greater than can be safely reached by divers.

“These discoveries, and the prospect of many more to come, reinforce the importance of the Fiordland Marine Area at both a national and international level,” says Fiordland Marine Guardians Chairman, Malcolm Lawson. “The Fiordland Marine Guardians are pleased to be able to work alongside DOC and NIWA in identifying areas for future exploration.”

Only Doubtful and Dusky Sounds have been explored so far. Says Dr Handley: “We’ve found marked differences in fauna and habitats between the two, so it stands to reason that Fiordland’s marine environment as a whole could harbour an extraordinary diversity of life.

“It is an important area to study, because it is geologically unique and largely undisturbed by human activity.”

Sea pens are coral-like organisms that colonise the seabed and ledges by burying themselves in soft sediment. But, unlike coral, they lack a hard ‘outer skeleton’.

“They’re essentially row-upon-row of feeding polyps growing out of a soft stalk,” Dr Handley explains, “hence their resemblance to feathers or quill pens.”

At night, sea pens are luminous, which helps to attract the phytoplankton they feed on. Dr Handley says sea pen colonies generally indicate an unpolluted, undisturbed environment.

At 65 centimetres long, the specimens discovered in February are among the largest sea pens found in New Zealand. Elsewhere, however, sea pens of up to two metres in length have been found.

The new specimens will be logged in a biodiversity database and then international sea pen experts will be consulted to help formally identify and name them.

Footage of one of the species - Funicularina sp. - can be seen below. It's the first time this species has been seen in the area.

Fiordland’s depths reveal more new-to-science wonders - Funicularina sp. (sea pen) from NIWA on Vimeo.

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This sea pen specimen (Acanthoptilum sp.) was one of several discovered by NIWA and DOC scientists exploring the deep waters of Fiordland. [NIWA]

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Funicularina sp. was another of the specimens recovered in Fiordland's deep waters. [NIWA]