With his inimitable humour, enthusiasm and insight into nature, he gave children and adults an understanding of why it should be treasured and what they could do to protect it.
Born in London in February 1939, he spent his first summer as a baby in Jersey when his father worked as a chef at the Merton Hotel.
Many years later, as the author of a book about Channel Island flora, Mr Double wrote that he had been a late botanical starter because he spent his early years among the terraced houses and bombsites of south-east London where it would have been rather unwise to voice any interest in wild flowers.
He added at that time: ‘It took a couple of decades for the fact to filter through that without plant life, there is no life.’
In his late teens, he trained at Westminster College as a chef, gaining experience at some of London’s most famous hotels.
His introduction to music came when his father gave him a clarinet as a birthday present.
It was to be the start of a beautiful friendship which lasted a lifetime and particularly took off after he met musician Ernie Roscouet and joined The Black Butter Jazz Band.
Mr Double’s wide experience of life included a time in the Merchant Navy and then completing national service, before he came to the Island, where he had spent enjoyable school holidays.
With music and fishing his main interests, he was content to take on a variety of day jobs to earn a living, before turning his hand to writing and becoming the Jersey Evening Post’s angling columnist John Tellum (mullet backwards), and a staff member at the Magnet and Island Sun publications. His first marriage, to Muriel, led to them having two children, Amanda and Claire.
He later moved to Scotland and married Pat, and he turned his many talents to running a hotel, before planting trees for the Forestry Commission, and then working in a power station to save up enough money to buy a boat to fish on Loch Fyne.
Returning to Jersey with Pat and their children, Sarah and David, he wrote commercials for Channel Television.
Another one of his creative talents was as a film-maker, and among the subjects that he covered were the varied and colourful wildlife of the Channel Islands, and shipwrecks in island waters.
He found his dream job in 2000 as the Environment department’s education and awareness officer – it put him at the very heart of Jersey’s many beautiful but fragile habitats – where he was most at home.
Mr Double responded by creating the Planet Jersey exhibitions which introduced children and adults to ways in which they could play their part in the important job of conservation.
He was a great friend of naturalist Mike Stentiford with whom he shared a mutual understanding of wildlife, and owing to their contrast in size they were known as Little and Large.
Following the death of his wife, Pat, in 2001, Mr Double survived a serious fall from cliffs when out with his friend, artist Nick Parlett, who dived into a swell of over 15 ft to bring him to safety – a brave feat for which Mr Parlett was given a national award.
Years before, another friend Roddy Hays helped to save Mr Double’s life after he suffered a major heart attack in Alderney.
It was those two traumatic experiences which Mr Double’s family believe made him so passionate about everything he did.
Never able to get enough of the natural world, he was chairman of Action for Wildlife Jersey and a guide for Tourism – his walks out to Seymour Tower and Corbière lighthouse were extremely popular.
The Rock Pool Rambles at La Rocque he carried out for the National Trust were also a great success.
Throughout his life he was very proud of his family, and in more recent years, was the partner of tour guide Sue Hardy who became his constant companion.
With Mr Double’s death, Jersey has lost a man who loved the Island to his core. He wanted others also to appreciate its uniqueness and do all they could to preserve what made it so special.
The JEP extends sympathy to Mr Double’s family and friends.