Researchers from Aberystwyth University have carried out the first ever environmental DNA (eDNA) assessment of marine vertebrates in Tristan da Cunha, a group of volcanic islands in the South Atlantic Ocean.

By matching tiny traces of eDNA found in the water to a global database of marine species, they have been able to reveal rare and vulnerable species - such as the ocean sunfish Mola mola - as well as provide important evidence to support conservation efforts in the islands.

This technique has also helped to identify other fish species more accurately than traditional survey methods used around Tristan de Cunha, the most remote inhabited islands in the world and one of the UK’s overseas territories.

Tristan da Cunha’s isolated location, over 2,000 km from the nearest continental land, means regular assessment of its marine life can be challenging.

Dr Niall McKeown from Aberystwyth University was the lead supervisor on the research project.

Dr McKeown said: “Environmental DNA – whereby DNA is shed into the environment by organisms - offers a powerful sampling tool which can help solve the logistical challenges associated with traditional survey methods and support sustainable, long-term assessments.

“This research is well timed given the recent designation of the islands as a Marine Protected Zone which will benefit from long term ecosystem monitoring.”

The project was a collaborative effort between Aberystwyth University and the Tristan da Cunha Fisheries Department, as well as researchers from Queen’s University Belfast and the University of KwaZulu-Natal.

Megan Elsmore, a doctoral student at Aberystwyth University’s Department of Life Sciences led the research work after spending part of her childhood in Tristan da Cunha.

She said: “There is growing concern about the effects of climate change and human activities on marine life across the globe, with the biodiversity of remote oceanic islands like Tristan da Cunha particularly at risk.

“Traditional methods of monitoring and assessing – such as scuba diving or deep-water camera drops - can often be costly and time consuming.

“eDNA offers a safer, easier and more affordable solution to the need to monitor the biodiversity of the islands at a time when global extinction rates are alarmingly high.”

Megan added that the Tristan da Cunha Fisheries Department “were instrumental in creating the project, and provided vital support in assisting researchers with the collection of seawater samples.”

“We hope our research will help strengthen conservation efforts around these islands, which provide a vital habitat for a range of commercially and ecologically important species,” she said.

James Glass, the director of the Tristan Da Cunha Fisheries Department, and supervisor to the project said: "The importance of understanding the unique biodiversity of Tristan, and how eDNA techniques could enhance this understanding is vital, not just because of the incredible biodiversity that Tristan holds and protects, but because we are on the very front line of the consequences of climate change".

The study’s findings have been published in an academic paper in the peer-reviewed journal, Environmental DNA, and the full research can be found online.