As humans we take the seas around us for granted. Google searches for “space exploration” are twenty times more popular than “ocean exploration”. Yet, the vast majority of our oceans remain unexplored, with just five per cent mapped in great detail.
The space mission by astronaut Tim Peake during the first part of 2016 attracted the attention of many adults and children in Britain. Out of reach and out of sight, space exploration catches the imagination of humans all over the world and whets our appetite to find out more. So close and accessible to us, the seas around us don’t capture humans’ imagination in the same way.
In my experience our oceans have still so much to reveal. Having spent considerable time at sea over the last 15 years, each survey uncovered natural features, biological communities or shipwrecks society didn’t know existed. In June 2016, the Future of the Ocean Floor Forum brought together world experts in charting the oceans and together they developed a roadmap for comprehensive mapping of the ocean floor. Venus and Mars have almost had their entire surface mapped and over 75 per cent of the land surface of the UK has been surveyed. However, only about 30 per cent of the seas around the UK (and as little as five per cent worldwide) have been surveyed in high resolution using modern methods.
The British Virgin Islands is home to Richard’s beautiful Necker Island and neighbouring Moskito Island. The UK Overseas Territories are known for their unique environment and are home to an estimated 90 per cent of the biodiversity found within the UK. The BVI is also known as “the sailing capital of the world” – a prime tourist destination – welcoming some of the biggest cruise ships and highly dependent on shipping for the import of food and goods. Despite this, the seas around the BVI have never been surveyed using modern methods and the most recent survey can date back to the 1850s. In 2014, Cefas, the UK Hydrographic Office and the National Parks Trust of the Virgin Islands undertook the first high resolution seabed survey using modern mapping methods.
We worked with local stakeholders to identify a priority area which was surveyed using a state-of-the-art multibeam echosounder. This system allowed us to create a highly detailed model of the seabed, revealing the shape of the seabed as we would see it if we drained the water from the ocean. Such data are also extremely useful in managing the marine environment, marine resources, fisheries, conservation and marine spatial planning. A remotely operated cameras system was therefore lowered to the seabed in selected locations to complement the underwater terrain model, allowing us to describe the nature of the seabed (e.g. reefs or sediment) and the marine wildlife present.
This global voyage of discovery has barely begun and we need everyone to get on-board.
Whilst we didn’t find any treasure, the seabed gave away lots of other secrets. Having surveyed water depths in great detail now makes navigating the huge cruise ships into the harbour a lot safer. Seagrass meadows were observed more extensively than previously known. Seagrass beds are globally important ecosystems, providing a nursery ground for fish and other marine life, and are up to 35 times more effective than rainforests storing the carbon dioxide we produce.
Protecting these habitats is important to island nations such as BVI, vulnerable to the impacts of climate change. We were able to map the extent of seagrass bed and found 800 per cent more seagrass. Similarly, we were able to locate coral reefs in great detail and assess their health. Unfortunately, some of coral reefs were found to be impacted by human activities. We found evidence of anchor scars through coral reefs, damaging the marine life in its path. However, within RMS Rhone Marine Park evidence of the success of biodiversity protection revealed lush hard and soft coral communities with plentiful marine life.
Mapping of the seabed has made a significant difference for the Government of the Virgin Islands, allowing management of human activities around the sensitive seabed habitats, avoiding unnecessary and unintended damage. We can continue to manage blindly, but this will be at the expense of a healthy marine environment. Furthermore, the several hundred thousand visitors chartering a sailing yacht every year can now use their GPS enabled smartphone to avoid anchoring in ecologically sensitive or important seagrass or coral reef areas.
Of course, the work in the BVI hasn’t made much of an impact on the 95 per cent of the ocean floor still to be mapped and explored, but it has raised awareness. It has been suggested that mapping the entire deep ocean floor costs as much as a single mission to Mars. To get the international commitment, we need to continue to innovate, raise awareness and get the public and governments as interested in ocean exploration as they are in space exploration. This global voyage of discovery has barely begun and we need everyone to get on-board.