There are many beautiful sandy beaches around Scapa Flow. Waulkmill Bay, Swanbister Bay and Scapa Beach all border Scapa Flow on the Orkney Mainland. In South Ronaldsay, the sweeping beach at the Sands of Wright looks out into Widewall Bay, whilst at Barrier No4 the beach at the Ayre of Cara has only formed over the last 70years - as a result of the Churchill Barriers being built . The island of Graemsay has a beautiful beach, backed by dunes at Sandside, looking back over the Flow to Stromness. There are also many smaller sandy bays around the Flow, each with it's own character. Two good examles of small sandy bays are Kirk Hope Bay in South Walls and Lyrawa in Hoy.
Beaches are excellent places to search for seashells and other marine treasures. Some shellfish, like razor clams or spoots live burrowed in the sand, others like periwinkles may inhabit nearby rockpools or amongst seaweed. Then there are those, like mussels, that live in large aggregations or beds. What can be found on the beach depends on the types of marine creatures that live in the nearby waters and the direction of the currents offshore. Cowries or 'Groatie buckies' as they are called in Orkney are a favourite of many shell collectors, but it takes a keen eye to find them. There are two types of these dainty shellfish in Orkney waters, the spotted and the arctic cowrie. Both species are shown below, along with a good example of a blue-rayed limpet shell. These delicate relations of the common limpet can be found on a few beaches around the Flow but as they age, they lose the electric blue markings visible in the photograph.
As well as shells, other evidence of marine life can be found. Parts of animals like crab claws and carapaces are common along with the egg cases of fish and other marine organisms.
Inevitably, as well as natural marine flotsum and jetsum, man-made debris is often encountered. Some like driftwood, may be relatively harmless and in fact interesting, but large quantities of plastic waste such as disgarded nylon netting, containers, plastic bags and balloons can be unsightly and also dangerous to wildlife. Beach clean ups are organised by a local environmental group Environmental Concern Orkney each spring througout Orkney. The whole operation is called 'Bag the Bruck' and over 600 volunteers take part to help keep Orkney's beaches and coastline clean and safe.
A number of plants colonise sandy beaches. Sea rocket, orache and sea mayweed are common plants along the shore. In some locations, such as the Ayre of Cara, (shown below) dune systems have formed with whole assemblages of specialist plants. Some of these plants are essential to the formation of the dune itself, like marram grass - this species helps bind the highly mobile particles of sand to stabilize the soil.
One of Orkney's prettiest plants growing in this environment is the oysterplant. It is a nationally scarce plant but has a stronghold in Orkney. South Ronaldsay is a particularly good place to find oysterplant.