The deep sea is one of those mysterious parts of planet earth – or should that be planet ocean? It’s so far away and out of reach that most people only hear about it occasionally in the news or on wildlife documentaries. But did you know that deep sea ecosystems have a powerful influence on your everyday life and the environment around you? In this blog, we will take a dive into the importance of the deepest and most unexplored parts of our ocean, and look at what urgently needs to be done here in Scotland to protect the species and habitats that live in these hidden havens.
Stretching far beyond the familiar shorelines of Scotland’s coasts, beaches and cliffs, the offshore waters encompasses everything from the continental shelf to the deep sea abyssal plains, from 12 to 200 nautical miles. This vast and largely unexplored region is home to some of the most unique and fascinating species and habitats on Earth.
Along the continental shelf and within the dark, cold depths of Scotland’s seas, life thrives in extraordinary ways. Species such as the bizarre-looking deep-sea anglerfish (Lophius piscatorius), the majestic sperm whale (Physeter macrocephalus), and the elusive porbeagle shark (Lamna nasus) call these waters home. Habitats in Scotland’s offshore waters include cold-water coral reefs, which provide shelter and breeding grounds for numerous marine species. Seamounts and submarine canyons add to the complexity and diversity of these underwater landscapes.
These creatures have adapted to extreme conditions—immense pressure, frigid temperatures, and perpetual darkness. However, these conditions make for a much more stable environment than the busier and more dynamic inshore and coastal area. As a result, species and habitats tend to be slow-growing and long-lived. The orange roughy, a medium sized fish that lives at depths of up to 1,800m, can live up to 200 years! The ocean quahog, a species of clam found in Scottish waters, can live even longer, with the oldest recorded individual aged at 507 years old!
Image: Orange roughy (credit: unknown author, creative commons)
Image: Ocean quahog (credit: NatureScot on Flickr)
The continental shelf and deep sea environment plays a crucial role in global ecological health. It acts as a massive carbon sink, helping to regulate the Earth’s climate by storing vast amounts of carbon dioxide. The biodiversity of these environments contributes to the overall health of ocean ecosystems, supporting fisheries, helping to cycle nutrients to shallower waters and maintaining the balance of marine life. Deep-sea organisms are also a source of novel compounds with potential applications in medicine, biotechnology, and other fields. Recently, it was even discovered by Scottish scientists working at the Scottish Association of Marine Science, a pioneering institute on deep-sea research, that deep sea minerals produce oxygen! Until then, oxygen was only thought to be produced by plants and other living things that use photosynthesis and require sunlight.
Despite its remoteness, the offshore and deep-sea environment is not immune to threats. Human activities such as deep-sea fishing, mining, and oil and gas exploration pose significant risks. These activities can lead to habitat destruction, overfishing, and pollution, disrupting the delicate balance of fragile ecosystems. Climate change and ocean acidification further exacerbate these threats, altering the physical and chemical environment that deep-sea species rely on. Marine litter is also being increasingly found in deep-sea environments. A plastic bag has been discovered in the Marianas Trench – the deepest place on earth – at a mind-blowing 10.8 km deep, and deep sea creatures have been found entangled in or attached to plastic waste in multiple locations.
Most of these threats are already affecting Scotland’s offshore ecosystems, and some have done so for a long time. In the northwest area of Scotland’s offshore waters, a population decline of up to 90% has been estimated for orange roughy due to fishing activities. Strandings of deep-diving whales on Scottish beaches have been increasing over the last 60 years, including species such as Cuvier’s beaked whale (Ziphius cavirostris).
Protecting Scotland’s deep sea is not just about preserving the unknown—it’s about safeguarding the planet’s future. The health of our oceans is intricately linked to the health of our planet and human health and wellbeing. By conserving these environments, we ensure the continuation of critical ecological processes and the survival of unique species that could hold the key to scientific and medical breakthroughs. Whether we can see it or not, the deep sea is a vital part of our natural heritage.
In 2014, 13 new marine protected areas were created in Scotland’s offshore waters, adding to some of the MPAs already established under EU law (known as Special Areas of Conservation), such as the Anton Dohrn seamount and the Wyville Thompson Ridge. The West of Scotland deep sea marine reserve was also designated in 2020. However, as we have explained before, it’s not enough to just create the MPA without addressing the risks to the species and habitats that live there. During 2016, we participated in government meetings to discuss the fisheries management measures that should be established in the 13 offshore MPAs, plus 7 of the existing offshore Special Areas of Conservation. Those management measures still have not been adopted, apart from some voluntary protection currently being observed by fishers in the West Shetland Shelf MPA (long story involving cod and historic EU protections).
Delayed by Brexit and the Covid-19 pandemic amongst other things, the Scottish Government has now launched a public consultation seeking views on proposals for fisheries management in offshore MPAs. In the midst of a global ocean crisis, this consultation is a significant turning point for Scotland’s MPA network, the majority of which has remained open to seabed-contacting fishing activities that pose a direct risk to some of the delicate habitats and species these MPAs are designed to protect. Over the next six weeks, you have the power to make a difference. The current consultation on offshore MPA management is a crucial opportunity for us to protect our precious marine environments and ensure they thrive for future generations.
The consultation proposes two options in some of the MPAs: restricting fishing only in areas where the protected species or habitats are found, or restricting all towed seabed-contacting fishing across the whole MPA. The latter option will provide the greatest opportunity for the recovery of offshore ecosystems, from the continental shelf into the deep sea, and in the long-term will provide greater benefits to nature, people and sustainable businesses. By supporting proposals to restrict damaging fishing activities in these areas, we can help protect and restore the health of our vulnerable ecosystems. This isn’t just about preserving nature—it’s about safeguarding the resources and services we all depend on, from sustainable fisheries to climate regulation.
Proper protection for our offshore MPAs is already long overdue, and recovery of nature takes a long time in these environments – we need to give it the best chance possible before it’s too late. Your voice can help secure stronger protections for Scotland’s offshore MPAs. We urge you to participate in the consultation, support the proposed measures, and advocate for a future where both nature and people can prosper.
Submit your response through our campaign today.
By Esther Brooker, Marine Policy and Engagement Officer at Scottish Environment LINK.
Top image: Lisa Kamphausen, Nature Scot