Cayman Trough search planned

British scientists are preparing to explore a ‘lost world’ in the world’s deepest undersea volcanoes situated in the Cayman Trough in the Caribbean Sea.

deep sea

Autosub6000 lifted into its recovery cradle after its first deep sea mission in the Atlantic in 2007. Photo: Courtesy of National Oceanography Centre, Southampton

Mr. Jon Copley will lead a team from the National Oceanography Centre in Southampton, England, to explore a volcanic rift, 5,000 metres below sea level.

The likelihood of encountering mysterious creatures of the deep, a la Jules Verne, are high, Mr. Copley told the Caymanian Compass.

‘If you come across animals deeper than 3,000 metres – and bear in mind this volcano is 5,000 metres deep – there is a 50/50 chance it will be something that no-one has ever seen before,’ he said.

The team has been granted $747,700 by the Natural Environment Research Council to explore the Cayman Trough, which starts 46.6 miles south of Grand Cayman and runs 68 miles south beyond that toward Jamaica.

Mr. Copley said the team would bring a robot unmanned submarine called Autosub6000 on a Royal research ship, the RRS James Cook, in the first of two expeditions, which will be carried out over the next three years. On the second expedition, a remotely-operated vehicle called Isis will be sent down into the abyss from the ship to take close-up photographs and bring back samples.

The schedule for the expeditions has yet to be fixed as it depends on what other projects the RSS James Cook is involved in and where the ship is located, but Mr. Copley said he hoped that the setting-off point for the exploration would be from Grand Cayman.

The team will look for new marine species and geological features, using a whale-friendly sonar system to map the undersea volcanoes. They will also study the deep ocean currents in the Cayman Trough for the first time and hunt for volcanic vents on the ocean floor.

‘This is part of the 95 per cent of the ocean floor that is unexplored. There is so much out there that is yet to be explored,’ Mr. Copley said, adding that medical and technological leaps had been made in recent times due to deep-sea discoveries.

“The deep ocean is the largest ecosystem on our planet, so we need to understand its patterns of life,” says Mr. Copley, a lecturer with the University of Southampton’s School of Ocean and Earth Science. “Deep-sea exploration has also given us new cancer treatments and better fibre-optic cables for the Internet, both thanks to deep-sea creatures.

‘Through such research, we can help find out how our planet works. It is the missing piece of the global puzzle,’ said Mr. Copley.

Volcanic vents in the Atlantic and Pacific Ocean beds have been explored and shown to be inhabited by previously unknown creatures. The researchers hope to establish if similar or entirely new species exist in the Caribbean Ocean.

A lack of advanced technology and uncertainty over which nation could lay claim to that tract of ocean explains why this particular, scientifically important area has never been explored before. The exploration is now possible, thanks to deep-sea submarines and vehicles that can go to a depth of a little more than four miles and a decree by the United Nations in 2002 that the undersea volcanoes in the Cayman Trough were part of the British seabed territory.

Meanwhile, the Central Caribbean Marine Institute, while not involved in the UK project, is carrying out its own deep explorations of coral reefs, going down to depths of 520 feet at Bloody Bay Wall off Little Cayman.

CCMI’s president and director of research Ms Carrie Manfrino said the institute was asking similar questions on a local level to the UK scientists who will examine what connections, if any, there are between the volcanic vents found in the world’s oceans. Here in Cayman, CCMI is looking at the connections between Cayman’s shallow and deep reefs and the connections regionally.

‘We completed our first deep dives last month and made some pretty shocking discoveries. Our pilot research project, which we plan to continue over the next three years, was aimed at completing a zonation map of the animals and geology of the vertical walls of Bloody Bay to address the question: Are deep reefs important to the coral reef system’s survival and replenishment?,’ Ms Manfrino said.

CCMI’s research has indicated a massive 40 per cent loss in coral cover on shallow reefs of less than 15 meters.

‘Discovering how this loss is related to deeper reef communities has so far been impossible because even with mixed gas scientific diving, bottom times are not sufficient to measure total biodiversity, identify recruitment and measure disease outbreaks,’ she said.

During their exploration of Bloody Bay Wall, CCMI divers found that diseases were active on coral on the wall, and that the amount of live coral was minimal at 100 feet.

They also found an abundance of calcareous red algae at depth. Red algae are the deepest growing plants on earth, reported from San Salvador and now Little Cayman.

The CCMI researchers also established that sponges increased in size with depths to 280 feet, after which most were small and the amount of encrusting sponges increased, and that black spined urchins were scouring into the limestone at depth.

Ms Manfrino said this data would be combined with CCMI’s nine years of research on the shallow reef system to create the first continuous model of shallow-to-deep reef ecology in the Caribbean.

The programme will provide data for research into how reef species and conditions vary by depth, and what effect depth has on reef bleaching, resistance to disease, competition with fleshy algae, species diversity and the promulgation of reef species.