In photos: marine surveying a remote volcanic island

I’m Catriona Macdonald from the BGS Marine Survey team. My colleague Rhys Cooper and I recently returned from fieldwork on Ascension Island, a remote volcanic island in the South Atlantic Ocean. The reason for our visit was to complete a marine survey of the nearshore waters within the Ascension Island Marine Protected Area (MPA), one of the largest MPAs in the world.  The survey is part of the first stage of a project funded by the UK Government through Darwin Plus to map the seabed and nearshore habitats within the MPA.

Working with the Ascension Island Government (AIG) marine conservation team, we acquired new, high-resolution bathymetry data in specific nearshore areas around the island as part of an integrated programme of marine surveys. The data will be used to produce the first geomorphology, substrate and habitat maps of the MPA. These will help to inform better management and monitoring of the marine environment, as well as enhancing our geological understanding of the sea floor around Ascension.

Completing a marine survey at the best of times can be extremely difficult, but, given the remoteness of Ascension Island, this project presented its own unique set of challenges. To get to Ascension, we had to travel down from Edinburgh to RAF Brize Norton, Oxfordshire, and fly overnight on the ‘South Atlantic airbridge’, which stops at Ascension for refuelling before continuing to the Falkland Islands. Thankfully, the flight now goes directly to Ascension: major repair work on the island’s runway led to the suspension of airbridge flights in 2017, meaning that the flights were diverted via Cape Verde. The runway opened again in 2022.

Chief surveyor Rhys considered several boat options before settling on a RIB-mounted system to complete the survey. The solution was ideal for surveying in shallow, nearshore waters, but it meant that the working conditions were challenging due to the size of the boat, the amount of survey equipment on board and the limited cover from the elements.

Rhys Cooper discusses how the project is mapping some previously uncharted areas around the island.

The food supply on Ascension is limited and depends on supplies that are flown to the island. However, we made good use of the fresh produce from the local hydroponics laboratory, which opened in 2016 and sells leafy crops, tomatoes and potatoes in the local shops. On our last weekend, our hosts from AIG took fishing rods out on the boat and at the end of the day we had a go at fishing. I was lucky enough to catch a yellowfin tuna, which meant we ate very well over the last few days!

Ascension’s amazing landscape and wildlife made the trip more than worthwhile. Over the course of our trip, we completed many of the hiking trails around the island. We even managed to source some (very old) golf clubs to have a go at the infamous One Boat Golf Club, which is sometimes playfully referred to  as the ‘world’s worst golf course’. The team will return to the island in January 2024 to collect seabed samples and participate in outreach activities for local government and community groups living on the island. 

This project is funded by the UK Government through Darwin Plus.