Crofting is the mainstay of island life . Sheep form the backbone of the agricultural economy but a diversity livestock are kept , including cattle , pigs , goats , chickens , ducks and geese . Vegetable are grown too , often in the shelter of circular walls , such plots being known as ' plantie scrubs ' . Fishing is still conducted but on a relatively small scale . It is a post office at the pier , but no shop . Mains electricity only came to the island at the close of the twentieth century . The Papa Stour Project is a Christian supported housing service offering accommodation to men with drug and alcohol issues . Ferries now sail across the Sound of Papa to West Burrafirth on the Shetland Mainland . The crossing takes 45 minutes , and although the Snolda carries cars , it is only one short road on the island.For visiting yachts the four main voes provide good shelter , but the strong tides in both the Sound of Papa and to the north west require considerable care .