Graham Thomas Reels was born in Germany, where his father was serving in the British Army of the Rhine, in 1964. He spent his early childhood in Cyprus, Canada and England, before moving to Hong Kong in 1975, where he attended King George V School in Kowloon, returning to England in 1981 to study at Cricklade College, Andover, and Hatfield Polytechnic.

In 1988 he came back to Hong Kong to take up a lowly position at the Zoology Department of Hong Kong University – the start of a ten-year association with that institution. During the 1990s he studied for a M.Phil. degree at Mai Po marshes before conducting a survey of Hong Kong wetlands followed by a territory-wide Hong Kong biodiversity survey. He also co-founded and edited the Hong Kong natural history newsletter, Porcupine!, and was attached to Kadoorie Farm & Botanic Garden for a number of years before turning to ecological consultancy.

Since 2009 he has focused on writing and editing. He currently lives in Hampshire, England.