The Fraser Island Defence Committee was formed by voluntary conservationists in January 1971 in response to applications for sand mining leases on the island. The name was soon changed to Fraser Island Defence Organisation, giving the acronym and motto "FIDO, the watchdog of Fraser Island". The organization ran successful campaigns to stop sand mining and logging on the island, and expanded to focus on the conservation of the Great Sandy Region as a whole. Fraser Island Defence Organization (FIDO) (1976-). Formerly Fraser Island Defence Committee (1971) and Fraser Island Defence Organization (1971-1976). Objectives - To promote the wisest use, in the long term, of the natural resources of Fraser Island by activism and lobbying, by education, by sponsoring research on Fraser Island and by combining revenue raising with the increase of people's appreciation of Fraser Island. Publicists - John Sinclair. Notes: FIDO is a member organization of the Queensland Conservation Council.

From 1976 [?] the organisation has been known as Fraser Island Defenders Organisation. Now their motto is "FIDO, 'The Watchdog of K’gari'”.

John Sinclair was born on 13 May 1939 at Maryborough, Queensland. He received a Diploma of Agriculture at the Queensland Agricultural College (now the Gatton campus of the University of Queensland). In 1974 he completed his Bachelor of Economics degree at the University of Queensland, followed by a Diploma in Continuing Education from the University of New England in 1980. Some of the organisations in which he has been involved include the Maryborough Field Naturalists' Club, Gympie Field Naturalists' Club, Wildlife Preservation Society, and he was president of the Fraser Island Defence Organisation (FIDO) when it formed in 1971. He was made an Officer of the Order of Australia in 2014 for his services to conservation of the environment. He died on 3 February 2019 in Auchenflower, Brisbane.