Mapping the deep

At the frontier of marine science, scores of Plymouth researchers are leading the way in advancing knowledge and transforming our understanding of the environment. Nowhere is this better demonstrated than in the work that has taken place to document the existence of previously undiscovered cold water reefs – research that has underpinned the introduction of Marine Protected Areas.

Thanks to robot vehicles capable of diving down to depths of 1,300m, innovative predictive mapping techniques, and the odd submarine trip, academics in the School of Biological and Marine Sciences have identified vast forests of coral off the coasts of Scotland and Ireland, and even up in the Arctic circle. In the process, they’ve uncovered evidence of catastrophic damage done by modern fishing methods – and proposed innovative methods to police against it.

Professor Jason Hall-Spencer saw for himself the impact of modern fishing methods on these fragile ecosystems when he was working on a French fishing boat in the North Atlantic in 1998 and watched in amazement as lumps of coral were dragged up from the deep. He has since worked on a number of research projects to gather further evidence of the location of these reefs. Jason said: 

“Coral reefs offer fish a place to breed, to feed, to hide, and they act as hotels for invertebrates that otherwise wouldn’t be there. If we bulldoze them, we’ll destroy that ecosystem – and these spindly reefs cannot withstand the impact of tonnes of metal dragged by fishing vessels. One trawl can cause thousands of years’ worth of damage.”

Dr Kerry Howell, Associate Professor of Marine Ecology, has played a crucial role in surveying and mapping the deep, providing the evidence for governments and bodies such as the International Council for the Exploration of the Seas upon which to base their decisions. Gathering that research has meant Kerry spends weeks at a time out at sea, using multibeam sonar technology to visualise the seabed and its underwater structures.

She said: 

“We multibeam huge areas of the sea and then use video equipment to analyse the type of terrain in which we find the cold water corals. It means that when we find similar terrain, we can predict with far greater certainty that they may be home to corals as well. We’ve been able to build up a rich picture of entire ecosystems, and that’s been used directly in the designation of Marine Protected Areas.” 

While unmapped coral reefs are still being destroyed by modern fishing methods, so the need for continued research is clear. Kerry is now leading a £1.2 million NERC-funded consortium to understand how different populations of marine life connect with one another at different depths.

Plymouth research has directly informed and shaped the implementation of global, European and national policies, such as the Oslo-Paris Convention (OSPAR), the European Habitats and Species Directive, and the Marine and Coastal Access Act (2009). That act led to the creation of two initial MPAs at Rockall Bank and Hatton Bank, covering just over 20,000km2 in total. It was a move backed by the North East Atlantic Fisheries Commission (NEAFC), which agreed to implement fisheries closures in these areas. More MPAs have since been established, along with an agreement by the European Commission’s Directorate-General for Maritime Affairs and Fisheries to support the implementation requirements of the European Marine Strategy Framework Directive. 

Kerry said:

“What we’ve achieved at Plymouth represents a major step forward in the management of the marine environment. By presenting the evidence and proposing solutions, we’ve helped support change for the better.”

Professor Jason Hall-Spencer

We’ve come a long way since 1998 when the only people who seemed to know about the reefs were the fisherman.

“But we have to continue to renegotiate the way we use the marine environment. The long-term sustainability of the fisheries depends on complex habitats, so we need a network of protected areas where damaging practices are banned.”

added Jason.