Science reaches new depths
Technology is allowing researchers and enthusiasts to explore the ocean floor from thousands of kilometres away. By Ged Cann.
Asmall group of scientists from the New Zealand Institute of Water and Atmospheric Research (Niwa) share some instant coffee on a calm Wednesday morning in Wellington.
While they enjoy the familiar surroundings of Evans Bay Parade, they are actively exploring more than 2000 metres below the sea.
Laptops sit open on a conference table strewn with books on species identification, and a flat-screen television stands at one end of the room.
They are all showing the same ghostly images, fields of towering coral and barbed crabs, which shrink away from the unnatural light from two remote-controlled submersibles.
The US research vessel, Okeanos Explorer, is 250 kilometres north of the Cook Islands, connected to the submersibles by a thin 3000 metre tether.
The Deep Discoverer and its sister vehicle, Seirios, are providing live video via satellite to the Niwa scientists, but they are not alone.
Over a conference call, the crackly voices of a specialist in Russia and another in Japan can be heard in a passionate conversation about a new form of sea sponge they have just spotted, which, to their knowledge, is a new discovery to science.
Niwa principal scientist Malcolm Clark is convinced the strange creature hasn’t been seen before.
‘‘I’m used to either soft sponges or hard sponges, but this one was really hairy,’’ he says.
‘‘It looks quite different, it’s almost transparent.’’
The discovery can be confirmed later, because the three-metre high remotely operated underwater vehicle (ROV) has another trick up its sleeve.
After a few moments’ debate, the American crew agree it is worth a sample.
We are not just limited to the couple of us on the ship. We have an unlimited number of scientists who can join us at any one time, just by having a phone and an internet connection. Kasey Cantwell
A mechanical arm reaches out and gently retrieves the sponge.
The sample will eventually work its way to the Smithsonian Institution in Washington DC.
The ROV does all this while coping with pressures 600 times those at sea level.
They contain 4000kg of equipment, more than 900m of electrical wiring, and have nine video cameras aboard.
Twenty LEDs provide the light needed to illuminate environments where the brightest objects are the faint glow of phosphorescent fish.
This is the first time this area of ocean has ever been seen, and for Clark, the highlight of the day was the sight of sweeping forests of bamboo corals, which grow as tall as the submersible itself.
Niwa deep-sea scientist Di Tracey said the research was key to directing New Zealand’s fishing and seabed mining efforts.
‘‘We have to know what’s there already, before these resources are even thought about being extracted,’’ she says.
‘‘The more information you can build up around quantities and species that are in the region, the better, and it also informs the management of closed areas and protecting areas.’’
The expedition began in Pago Pago, near American Samoa, in late April, and will end in Honolulu, Hawaii, on May 19.
The Okeanos Explorer is the only US government ship dedicated exclusively to ocean exploration.
During this expedition it will conduct dives nearly every day in a variety of deep-sea coral and sponge habitats, bottomfish habitats, and seamount atolls, as well as the the high seas themselves.
Rare sights already captured include a dumbo octopus lounging on the ocean floor and a giant bioluminescent siphonophore drifting lazily through the water, resembling a gelatinous glow stick as it emits a peachy orange glow in the blackness.
Radiant cosmic jellyfish and a fierce battle between a caridean shrimp and a midwater dragonfish also provide highlights.
The expedition provides more than create sightings, however; mapping data from the voyage will eventually be fed back to the likes of Google Earth and nautical charts to create more accurate maps of the sea floor.
The expedition is part of a threeyear campaign to collect deepwater information that will inform decisions on protected areas in the Central and Western Pacific.
These areas contain some of the last pristine marine ecosystems on the planet and are thought to harbour numerous protected species, as well as more than a few undiscovered shipwrecks.
There are 26 crew members aboard the Okeanos Explorer, and on this particular morning they are joined by colleagues from eight states across the US and Canada.
On-board science lead Del Bohnenstiehl says it is not unusual to have 30 experts on the line, and for no one to be able to identify what they were seeing.
Despite having basic ideas of the topography of their dive sites, Bohnenstiehl says they often find a totally different environment.
‘‘Today, on the ridge we are diving on, we were expecting it to be 1000 metres deeper than it is,’’ he says.
Expedition coordinator Kasey Cantwell says her favourite moment of any expedition was the moment the line became quiet as no one could tell what they were looking at.
‘‘We are not just limited to the couple of us on the ship,’’ Cantwell says.
‘‘We have an unlimited number of scientists who can join us at any one time, just by having a phone and an internet connection – it’s pretty amazing technology.’’
‘‘The comparison to the Mars Rover is a good one. Seventy per cent of our planet is covered by the ocean, but we know so little about it; 95 per cent of the ocean is unexplored.
‘‘A lot of what we do on this ship is we go to places people have never been, to see things they have never seen before.’’