Underwatertimes.com News Service - November 7, 2011 19:59 EST

Top marine scientists from around the world are setting off on a six-week cruise on board the RRS James Cook today to explore underwater mountains â€" or seamounts â€" of the southwest Indian Ocean Ridge. Their main focus will be to study species which live on the seabed and to understand the impacts that deep sea fishing has on marine life in the region.

"Seamounts are underwater mountains which rise to at least 1,000 meters above the sea floor", says Aurélie Spadone, IUCN's Marine Programme Officer and a member of the team on board. "Because of their interactions with underwater currents, the biodiversity that develops around them is remarkably rich. They attract a great diversity of species and act as a type of 'bed and breakfast' for deep sea predators such as sharks, which often feed on seamount communities."

But this impressive richness and diversity of life is facing many serious threats, many of which come from human activities.

"The limited knowledge of species associated with seamounts that we have today indicates that many of them grow and reproduce slowly, which makes them particularly vulnerable to overexploitation," says Carl Gustaf Lundin, Director of IUCN's Global Marine and Polar Programme. "Deep-sea bottom fisheries, including bottom trawling, can damage seamount habitats and negatively impact fish stocks. It can also irreversibly damage cold water corals, sponges and other animals."

The southern Indian Ocean remains a significant gap in current knowledge of seamount biodiversity. Scientists on board the RRS James Cook are hoping to find out more about it.

"Seamounts are an oasis for species living in the deep sea", says Alex Rogers of the University of Oxford and chief scientist on board. "We're hoping that this expedition will help us better understand this unique marine life and assess the threats it faces. Based on what we learn by studying five seamounts in the southwest Indian Ridge, we're hoping to get a better idea of where special habitats, such as cold water coral reefs, occur on seamounts and how we can protect them in the ocean globally. Perhaps we'll also be lucky enough to discover some new species living in these virtually unknown waters."

This is the second time scientists will explore the area. A similar expedition took place in 2009 and resulted in the first ever comprehensive survey of marine life above seamounts. It also led to the discovery of a new species of squid. This time the spotlight is on marine life living near the bottom of the ocean.

Both expeditions are part of the Seamounts Project funded by IUCN, the Global Environment Facility and the UK Natural Environment Research Council.

Follow the expedition blog