Scientists are to explore underwater mountains in an expedition to study species on the seabed and understand the impacts of deep sea fishing on wildlife.
The International Union for the Conservation of Nature (IUCN) said marine scientists will be spending six weeks on a marine trip to examine the seamounts of the south-west Indian Ocean Ridge.
Seamounts are mountains that rise to at least 1,000 metres above the sea floor. They contain a rich array of wildlife because of their interactions with underwater currents and attract deep sea species such as sharks which feed on creatures found there.
A similar expedition in 2009 resulted in the first comprehensive survey of marine life above seamounts, and the discovery of a new species of squid.
The IUCN said this trip will focus on marine life near the bottom of the ocean.
Carl Gustaf Lundin, director of IUCN's global marine and polar programme, said: "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.
"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."
Alex Rogers, of the University of Oxford, and chief scientist on board for the expedition, said: "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 south-west 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."