Diary from the Deep

A team of scientists has set out on a six-week mission, funded by the Natural Environment Research Council, to explore the Indian Ocean’s underwater mountains, or seamounts.

The scientists aboard the research vessel, the RRS James Cook, will study life thousands of metres below the surface.

In the second of her BBC Nature diary entries, Aurelie Spadone from the International Union for the Conservation of Nature, who is part of the team, explains what makes seamount habitats unique.

I have been on board the RRS James Cook for almost three weeks now, and I’ve settled in to a routine.

Each day is like the previous one in terms of rhythm. We worked at defined hours, there is no weekend and we take our meals at the very same time each day.

But one thing that strikes me is that our perception of time is very different at sea than on land. It is difficult to remember which day of the week it is. Two weeks seem like a whole month, but sometimes an entire day flies by in what seems like an hour. Time is like an elastic band here.

We also take turns to be on watch, and these shifts make it even more difficult; some people wish you a good morning at 4pm, or a good night when you’ve only just got up.

The boat has now reached the second site of the cruise plan: Melville bank. We are going to stay a few days in the area to conduct the same surveys we did on Coral seamount.

The comparison promises to be interesting. Melville bank is north-east of Coral seamount and it lies in warmer waters. Just by standing outside on the deck today, I could feel the increase in temperature. We are definitely moving away from polar regions.

Despite the routine, we all have to keep in mind why we’re here. And that is these mountains lying hundreds of metres under the ship’s keel and the amazing life they host.

Seamounts are defined as features of the ocean floor that rise to at least 1,000m. They may have different origins, some were made by tectonic plates that pushed them up from the seafloor, and some by volcanic eruptions that built new “molten mountains”.

There are over 100,000 seamounts in the oceans which provide shelter for a large group of corals, sponges, small fish, sea stars, sea spiders, crabs etc. They act as short-term accomodation for a large number of predators, including sharks, squid and tuna.

Life under pressure

Some of the animals that live in these strange habitats live without light and with pressures of up to 50kg per square centimetre on their bodies.

The isolation of seamounts also makes them very special. We could compare seamount habitats in the oceans to oases in deserts in terms of relative richness of life there. Life finds a way in improbable places.

I think we have a responsibility to protect this improbable life and make sure we don’t eradicate it before we have even had the chance to discover it properly.

Slow growth and slow recovery are typical features of the deep-sea communities, and that is why we have to protect them before too much damage is done. We still have a lot to learn about how these underwater mountains are connected and how species evolved on one side of the planet and on the other side in similar environmental conditions.

Source: bbc.co.uk