Greenpeace is well known for non-violent direct action in support of conservation. Very recently, they took a bold step in the German North Sea when they placed large granite boulders, each weighing two to three tons, around the Sylt Outer Reef. This reef is one of the few areas of rocky sea bed in the North Sea and is designated as a Special Area of Conservation under European Law. At first glance it might seem like some madness has overcome Greenpeace activists since the reef is officially protected. But Greenpeace's action highlights the present weakness of marine protected areas in Europe. Special Areas of Conservation (SACs) are intended to protect sites that support species and habitats determined by European legislators to be important. In the sea, this means reefs, caves, shallow sandbanks and a few other habitats, and a rather short list of species that includes charismatic animals like the Harbor Porpoise. Setting aside the problem that the list of habitats and species SACs can protect is brief, arbitrary, and fails to encompass anything like the range of wildlife that needs protection, at present most SACs offer little benefit to marine life at all. SACs are intended to maintain habitats and species' populations in ‘favourable condition', which in practice usually means little more than ‘not declining'. To designate one, conservation agencies seek places with sufficient in the way of life that it seems worth having one. In most cases, it is assumed that these places are in favourable condition and management is therefore focussed on preventing decline. If you take this view, as many government conservation agencies have, it implies that present uses of a site are entirely compatible with conservation. This is rather convenient if you want to avoid having to upset anybody whose activities might be curtailed, and it is certainly a good way to save money on management costs. But it is a policy that is failing Europe's marine life badly. In my view, the acronym SAC perhaps more accurately expands to Suspicious Absence of Conservation! The problem with this thinking is that it fails to redress past human impacts that have degraded the sites. A little history is in order here. In the mid-19th century and before, a vast area of the Southern North Sea was crusted with oysters and a myriad of other invertebrates including corals, seafans and sponges. In the 1880s, newly invented steam trawlers began to drag their nets back and forth across the seabed to catch fish, in the process tearing up marine life. Before long, little of this highly productive habitat remained, leaving behind the shifting sands and gravel familiar today. The last commercial catches of oysters were made in the 1930s and the last living oysters were caught in the 1970s. Only a few pockets of hard bottom remain, like the Sylt Outer Reef. The German government has not protected the Sylt Outer Reef SAC from bottom trawling. Greenpeace's boulders are intended to help achieve what they have not. In the Mediterranean, many seagrass meadows have been damaged or destroyed by bottom trawlers. France and Spain have both seeded important areas of seagrass with anti-trawling reefs that snag and tear trawl nets, keeping fishers out. Hopefully, the Sylt Outer Reef will at last get the protection it deserves. ———- Callum Roberts is Professor of Marine Conservation at the University of York in England and the author of The Unnatural History of the Sea. Click here to visit his website.