SIR William Wilkinson, who has died aged 63, will be remembered as one of the most distinctive chairmen of the Nature Conservancy Council since the 1940s.

Recognised by fellow conservationists as a man of great moral conviction and integrity, he was instrumental in pushing forward the NCC's crucial policy statement on forestry in 1986 which effectively led to the ending of tax incentives being paid for blanket conifer-planting schemes.

Among the greatest battles of his chairmanship of the NCC from 1983-91 were those fought to protect Duich Moss, the Flow Country in Caithness, and Creag Meagaidh from exploitation by private forestry interests.

With his support, the NCC bought Creag Meagaidh to keep it in public ownership, and the Royal Society for the Protection of Birds, of which he was a guiding force, bought Abernethy Nature Reserve. Both areas are now held up to land-users and politicians as prime examples of how successfully regeneration can be achieved.

His financial acumen and ornithological expertise were highly valued by the RSPB, on the council of which he served from 1970 to 1983. As the society's treasurer he guided the RSPB through its financial difficulties of the early 1970s and saw membership grow from 67,000 to more than 350,000 during his term of office.

The success of the RSPB's gamble, as it was then perceived, in buying Loch Garten, the home of the osprey, gave him particular pleasure. The purchase has had an enduring effect on the profile of the society.

Some commentators believe that it was the strength of his defence of conservation interests in the Cairngorms and Caithness that ultimately persuaded the Government in Westminster and the Scottish Office to devolve the powers of the NCC on to three bodies merged with the Countryside Commissions serving Scotland, Wales and England.

The break-up of the NCC, implemented under the Environment Protection Act 1990, and one of the last acts of the then Environment Secretary Nicholas Ridley, was vigorously opposed by Wilkinson, who felt the plans were ``half-boiled''.

He argued that the new bodies would be under-funded and ill-equipped to assess conservation needs on a national basis. In the face of the Government's determination to go ahead with the changes under Ridley's successor Chris Patten, he put all his efforts into trying to ensure that the new bodies inherited a strong structure and that staff retained their positions.

The bulk of his career, however, was spent in industry and merchant banking. That said, his first love was wildlife and its protection, in particular birds - a passion he maintained concurrently with his business career.

During his career he held a number of directorships - at Lonrho in the early 1970s, and at the merchant bankers Kleinwort Benson from 1973 to 1985. From 1986 to 1990 he was a board member of the former Central Electricity Generating Board.

Eight years ago, he was struck suddenly and permanently with near-blindness. Despite that handicap, he continued to fight the NCC's corner. Even after its demise, he supported voluntary conservation bodies and helped to raise their profile.

He was chairman of Plantlife and president of the London Wildlife Trust and of the British Trust for Ornithology. As chairman of Birds of the Western Palaearctic he helped to see his nine-volume series of definitive bird books through to completion.

His other great love was music, especially opera, and he had a fine baritone voice.

In 1989 he was knighted for his services to nature conservation, and in 1993 he was awarded the Wildlife Trust's Christopher Cadbury Medal.

He is survived by his wife Kate, a son and two daughters.