An underwater canyon

A recent review of studies of submarine canyons has identified that they are at risk from human activities, and require better protection. 

The review was published in the journal Frontiers in Marine Science by a team of scientists that are part of the International Network for submarine Canyon Investigation and Scientific Exchange (INCISE) - including those at the University of Plymouth. INCISE is an initiative that aims to bring together scientists working on all aspects of submarine canyon research, and to stimulate discussions across disciplines.

Submarine canyons are major geomorphic features of continental margins, and nearly 10,000 large canyons are estimated to exist around the world. Recent multidisciplinary projects focused on the study of canyons have considerably increased understanding of their ecological role, the goods and services they provide to human populations, and the impacts that human activities have on their overall ecological condition. 

Pressures from human activities include litter, fishing, dumping of land-based mine tailings, and oil and gas extraction. The effects of climate change may modify the intensity of currents within canyons, which is predicted to impact the structure and functioning of canyon communities as well as affect food supply to the deep-ocean ecosystem. 

Ulla Fernandez-Arcaya, of the Institute of Marine Sciences (ICM-CSIC), Barcelona, Spain, and the lead author of the review, said: 

“Our review not only identifies the ecological importance of canyons, but also highlights the need for a better understanding of anthropogenic impacts on canyon ecosystems.” 

Canyons face a number of current and future issues for their conservation, and the review study proposes the types of research required to inform management measures to protect canyon ecosystems. Only 10 per cent of all canyons identified worldwide are completely covered by marine protected areas (MPAs), and these are not evenly distributed around the globe. Furthermore, submarine canyon protection is mainly focused on the shallow parts of canyons, and researchers say it is important to protect complete systems, given their role as the main connection between shallow and deep waters.

Dr Veerle Huvenne from the National Oceanography Centre and Dr Jaime Davies, Research Fellow at the University of Plymouth, coordinate the INCISE network and are co-authors of the review. Dr Huvenne said:

“Submarine canyons are some of the most important environments along our continental margins, which can host very rich ecosystems and can support rich fisheries. However, as a result of their steep terrain and their complex oceanography, they have always been very difficult to investigate. Thanks to rapid technological developments, especially in marine robotics, we can now study these environments in much more detail. The CODEMAP project, funded by the European Research Council, makes use of such technologies, available at the National Oceanography Centre.”

Dr Davies added: 

“Few people know that we have two submarine canyons in UK waters, and while these ones are currently protected by a Marine Conservation Zone, this review highlights that this is the exception rather than the rule. More than ever, it is necessary that research from different disciplines is combined, in order to create a full picture of what happens in these submarine valleys. The INCISE network is providing the perfect platform to make this happen.”