Many of our reserves feature fascinating archaeological sites along with spectacular wildlife. Crystal Maw, a Project Officer at RSPB Scotland, tells us about some of the prehistoric sites on Colonsay and Oronsay.

The Hebridean islands of Colonsay and Oronsay boast a wide range of prehistoric sites, including early shell mounds, three cairns, eight standing stones, eight hut circles, five ancient field systems, nine forts and an impressive medieval priory.

 The medieval priory on Oronsay. Photo: Andy Hay

Perhaps the most mysterious and telling archaeological remains are the shell middens of Oronsay, known locally as Sheeans, or fairy knowes.

These middens are mountains of kitchen waste and blown sand left in hollows along the coast.  They were created by Mesolithic hunters who started to arrive here around 7500BC, and carbon dating shows that these people were using the island for at least 700 years between around 4100BC and 3400BC.

The mounds are composed mainly of limpet shells, but an array of other items has been found, including pierced cowries shells (presumably used for jewellery), bone pins and the remains of a seal, otter, red deer, pig and dolphin that no doubt were used for food and for clothing.

Bones of cormorant, shag, goose, shelduck, water rail, ringed plover, tern, gull, razorbill, guillemot, gannet and red-breasted merganser were found. Most exciting of all, eight bones of the now extinct great auk were discovered.  This prompted the naturalist Symington Grieve to write The Great Auk, or Garfowl: Its history, archaeology, and remains in 1885.  The auk must have bred on the skerries around Oronsay and been hunted for food.

 The Chough is on the Amber list due to small population size and historically declining population. Photo: Andy Hay

Oronsay is one of the most important Mesolithic sites in Europe.  RSPB Scotland has been managing the island as a reserve since 1996, in a farming partnership with the owner, to increase the populations of species such as chough and corncrake.  But our role includes protecting the heritage of the island for future generations.

The fairy knowes still hold some mystery.  We do not know whether the midden sites were permanently inhabited by those ancient, hardy communities or intermittently visited from the island interior or other nearby islands.  Another question that springs to mind is why people suddenly stopped living here all that time ago.  Perhaps there is much more to be discovered on Oronsay....

Fancy a visit? Oronsay is accessible from Colonsay at low tide and you should follow local advice before crossing.  The crossing is only suitable for 4x4 vehicles.

For more info visit: