Scientists Called for Urgent Conservation of Deep Reefs, One of The Planet’s Largest & Least Protected Ecosystems

By The University of Oxford
  • A new study finds very few deep reefs have any form of protection and face a multitude of threats, set only to escalate in the near future. 
  • Deep reefs are found below 30m and have a larger geographic range than shallow reefs. 
  • Deep reefs are biological hotspots, essential for climate change resilience, ocean health, and food security, and a refuge for ocean life threatened in shallow waters
  • Ahead of the UN Biodiversity Conference, COP15, researchers called on policymakers to put in place specific actions and targets to protect deep reefs.

As UN Biodiversity Conference, COP15 agreed to halt and reverse nature loss, an international team of marine scientists and conservationists have made an impassive plea for the urgent conservation of deep reefs.

Their calls were based on a new study, recently published in the journal Conservation Letters, led by scientists from Nekton, the Western Indian Ocean (WIO), and the University of Oxford. This confirms for the first time that deep reef habitats, notably in the WIO, are largely unprotected despite being under threat from a multitude of stressors, including overfishing, pollution, climate change, and, in the near future, seabed mining.

Their calls follow COP27 in Egypt, where many scientists, politicians, and campaigners concluded that the 1.5C climate goal died, signing the death warrant on the vast majority of shallow reefs.

Deep reefs (found >30 m) provide essential ecosystem services for climate change resilience, ocean health, and food security whilst also acting as a refuge for organisms threatened in shallow water, including commercially important species. Despite this, deep reefs are barely protected, even though they have a larger geographic footprint than their shallower counterparts. Furthermore, the scarcity of fish in shallow waters combined with modern deep-sea fishing technologies is resulting in deep reefs being increasingly exploited by coastal communities that need fish for their food security.

“We strongly encourage deep reefs to be included in conservation and sustainable management action to complement global targets, notably 30% protection of the global ocean by 2030,” said the study’s lead author, Dr. Paris Stefanoudis, a marine biologist at the University of Oxford’s Department of Biology and a Research Scientist at Nekton. “Deep reefs are critical to a healthy marine ecosystem and face similar threats from overfishing, pollution, and climate change faced by the much-imperilled shallow reef system.” 

Covering over 8% of the global ocean, the Western Indian Ocean is one of the least known, least protected, and most threatened marine regions of our planet. Shallow and deep coral reefs of the WIO are marine biodiversity hotspots with high numbers of species that are found nowhere else on Earth. They are essential to the region’s 100 million people living within 100km of the coastline, including over three million people who are directly dependent on artisanal fishing for their livelihoods. The population is projected to double over the next 30 years, driving greater stressors on the ocean’s biological capacity to support lives and livelihoods. 

The scientific team has co-developed a new framework for conserving deep reefs including practical recommendations and specific actions for regional policy-makers, conservationists and scientists.

As the UN Biodiversity Conference, COP15, launches they urge policymakers to use the summit to agree to the following:

  1. Highly protect 30% of ecosystems by 2030 (‘30 by 30’), and include deep reefs in this target.
  2. Conserve deep reef ecosystems and their resources by specifically including them in fishery regulations, marine protected areas, and marine spatial planning.
  3. Extend current management efforts on shallow reefs to include deep reefs as these ecosystems are often connected.
  4. Invest in foundational, fundamental, and applied research on deep reef biodiversity, ecosystem functioning and provided services.
  5. Develop national, international, and transnational cross-stakeholder collaborations to survey and conserve deep reefs in national and international (High Seas) waters

“To halt and reverse nature loss, the UN Biodiversity Conference, COP15 must prioritise the conservation of unique ecosystems such as deep reefs, one of the least protected ecosystems on Earth” stated co-author Professor Lucy Woodall, Professor of Marine Biology at the University of Oxford, Nekton Principal Scientist, “We hope our recommendations and actions will be useful for decision makers in the WIO, be applied within the new Western Indian Ocean regional policy and provide the springboard for deep reefs to become protected across the global ocean”, continued Professor Woodall.

Co-author Melita Samoilys, CORDIO East Africa explains: “Our framework was jointly developed with a range of stakeholders from academia, research, management and government, and provides a list of actions across three themes: capacity, information collection, and information sharing. Given the scale of the issue, we have also identified which parties – such as funding agencies, government, Institutions or the research community – are needed to work together to realise those actions”. 

“To ensure a prosperous and resilient Western Indian Ocean, it is essential that deep reefs are no longer ignored by scientists and policy makers, and they must be specifically considered in conservation and management strategies”, shared co-author Athur Tuda, Executive Director of the Western Indian Ocean Marine Science Association, WIOMSA.


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This piece was prepared online by Panuruji Kenta, Publisher, SEVENSEAS Media