Where no one has gone before: exploring the depths around Ascension

October 23, 2015


Charles Clover, our chairman, has just returned from Ascension where scientists from six major national institutes carried out a first-ever exploration of the deep water around the island.  This is what he wrote for the island’s only newspaper, The Islander.

You would need to have been stuck indoors all weekend – as some were, watching the rugby – to have missed the sight of a large red-and-white icebreaker, the James Clark Ross, sailing round and round the island, sometimes at full speed and sometimes appearing to stop and hold its position with uncanny accuracy.  What was it doing?

The 12 scientists from six top national institutes on the British Antarctic Survey vessel, including five from AIG, were looking where no human being has ever looked before, at the waters below dive depth around Ascension, from 100 to 1000 metres. As one excited member of the team put it at their first briefing, this was “the frontier of science.” Everyone was aware that, because of the island’s isolation, new discoveries, even new species, were highly likely.

Even the most basic information on what was down there was lacking: satellites had suggested a sea mount lay somewhere to the south, a few miles offshore.  This proved not to be the case when a beautiful bathymetric profile of the seamount that Ascension sits on emerged, the first picture of the seabed since the Navy did it with plumb-lines in the 1800s.  Elanor Gowland, data manager at BAS, said that the Navy’s lead plumb-lines turned out to be extraordinarily accurate as to depth, but they missed the hills, canyons and bottom features that we can now see.

The survey nearly didn’t happen.  Our little charity, the Blue Marine Foundation, had expressed an interest in completing the Darwin-funded AIMS project to assess the extraordinary wildlife in Ascension’s waters, with a survey of the deeper water around Ascension.  But until one funder stepped in the Friday before we arrived and our ambassador Amber Nuttall finished a sponsored paddleboard journey along the length of the Thames, I did not quite know how we were going to pay for the survey Paul Brickle, director of the South Atlantic Environmental Research Institute, and I had been discussing for a year.

So hearing the team being briefed by Dave Barnes, the chief scientist on the vessel and Peter Enderlein, the marine engineer who specializes in designing the tools, the trawls and drop-down cameras the scientists use, was tremendously exciting.   The safety rules – boots and helmets on deck – were exacting and the 12 hour shifts actually meant nobody slept for more than 3-4 hours.  Nobody wanted to, explained Judith Brown, AIG’s Director of Fisheries, for the camera images, and what came up in the trawls was just too exciting.  One unusual anemone was instantly dubbed the “sea bum” because of its unusual shape when it closed.  There was also, as she documented in her blogs on the SAERI and Blue websites, a lot of charismatic megafauna to be seen, such as a hammerhead shark and dolphins herding flying fish into the side of the ship to kill them.

Fast forward, then, to greeting the tired scientists back off the boat.  What were their first impressions? Dave’s was that the seabed was patchy, but given the age of Ascension, “we were surprised about how dense the biodiversity was in some places.  It was spectacular.”  He was also impressed by the number of creatures, like sea urchins, that were fixing carbon down there. The long spine pencils of dead ones littered the sea floor beneath the living. Vladimir Laptikhovsky, a marine ecologist, was captivated by a shrimp with long legs.  Chester Sands, a brittlestar specialist who normally works in Antarctica, got excited when he found a place densely populated with ones he didn’t recognise and the odd spiny lobster.  Sam Weber, senior scientist with AIG, mused on the narrowness of the band of life around the island.  This seems to be nourished by a kind of upwelling that you would expect around a continent rather than an island.

The business of turning first impressions into hard science now begins onshore. A flurry of activity is on going in the conservation laboratory as Dave Barnes and the team further analyse the samples and pull together a preliminary report, hoping the species collected either in the trawls or in the images prove to provide the ground-breaking information that we expect. Watch this space for more updates as the discoveries are unveiled.

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