Changes in the crops of Laminariaceae over a number of years around Scotland have been investigated. This paper summarises the results of five surveys carried out in 1947, 1951, 1952, 1953 and 1955 in North Shapinsay, Orkney Islands. Considerable losses were found between 1947 and 1952, but thereafter recovery commenced and has continued. Some of the ecological factors are analysed and discussed.