My friend Simon Pepper, who has died aged 70 of a heart attack, was founder director of WWF Scotland. He held the post from 1985 to 2005, playing a key role in establishing the Millennium Forest for Scotland and driving its expansion by securing £27m for more than 22,000 hectares.

At WWF Scotland Simon also led the formation of a highly effective alliance of environmental bodies called Scottish Environment Link, which now has more than 35 member organisations. It played an instrumental part in the successful opposition campaign to a huge quarry on Harris in the Western Isles, eventually persuading the French company Lafarge to drop its plans.

Additionally, he advised the then Secretary of State for Scotland, Donald Dewar, during the lead-up to his 1997 announcement of the government’s commitment to national parks in Scotland, which saw their establishment in 2002 and 2003. Crisply spoken, practical, cerebral and inspiring, Simon’s counsel was widely sought.

Simon was born in Worthing, West Sussex, to Richard, a GP, and Patricia (nee Mackenzie). After schooling at Radley college in Oxfordshire he studied zoology at Aberdeen University, where he won a rowing blue.

His first job, in 1971, was in Chad, with the Food and Agriculture Organization of the United Nations, working to reduce agricultural damage caused there by a sparrow-like bird, the red-billed quelea. Returning to the UK in 1973 he did a master’s degree at University College London before becoming a country parks officer in Essex from 1974 until 1978.

He then moved up to Scotland, where he bought a 42-hectare farm near Aberfeldy in Perthshire, refurbishing the farmhouse and starting up Cultullich Holiday Courses, a company that offered holidaymakers week-long visits to learn about the cultural and natural heritage of the place.

He ran that venture until 1985, when he joined WWF Scotland as its founding director. After 20 years at WWF he “retired” to be a consultant and to carry out various advisory roles.

In the year he left WWF he was elected as rector of the University of St Andrews, holding the post for three years. He was appointed a member of the Heritage Lottery Fund Committee for Scotland in 2011, chaired the grants panel of the Scottish government’s Climate Challenge Fund, and from 2017 became chair of the Deer Working Group, which is due to make recommendations on the sustainable management of wild deer in Scotland in 2019.

Appointed an OBE for services to sustainable development in 2000, Simon also served on the boards of many other government bodies, including Forestry Commission Scotland, Scottish Natural Heritage, the Deer Commission for Scotland, and a cabinet subcommittee on sustainable Scotland.

He is survived by his wife, Morag (nee Mackenzie), a publisher, whom he married in 1973, and by five children, 11 grandchildren and two great-grandchildren.