DR BRYAN Nelson who played a key role in the creation of the Scottish Seabird Centre and who is described as "the undisputed world expert on gannets" has died aged 83.

Dr Nelson was considered the world's greatest authority on the Northern gannet and an expert on pelecaniformes - a group of water birds.

He was honorary special ornithological adviser of the North Berwick-based conservation charity since 2013 after he stepped down from his role on the charity's board of trustees,

Dr Nelson had been a trustee of the centre from 1997 to 2012.

The seabird centre flag has been flying at half-mast in his honour.

Tom Brock, chief executive of the SSC, paid tribute saying: "As well as being the undisputed world expert on gannets, Bryan was a huge supporter of the Seabird Centre since its inception, long before opening in 2000.

"He was hugely proud of the Seabird Centre and its dedicated team of staff and volunteers. He was delighted that we successfully inspire and engage so many people of all ages about the amazing world of gannets. I was certainly inspired when I first heard Bryan speak... 37 years ago at Aberdeen University.

"Bryan had a huge influence on many people near and far, and he will be very sadly missed."

He was born in the West Riding of Yorkshire in 1932, going to school in Saltaire. While he first studied birds in the Yorkshire Dales, he was based in Scotland as an adult, studying zoology at St Andrews University before a PhD in Oxford and starting out as a researcher ringing gannet chicks on Ailsa Craig.

He spent most of his career on the staff at Aberdeen University and is best known for what he has revealed about the life of the Atlantic gannet. The Nelsons spent four years in total on windswept, inhospitable Bass Rock in the Firth of Forth studying the behaviour and ecology of the Northern gannets.

His study of gannets and the booby, a close relation to the gannet, took him all over the world, including a spell on the famous Galapagos Islands, the Peruvian Guano Islands, New Zealand and Christmas Island.

As a zoology lecturer, he amused and inspired thousands of Aberdeen University students.

In 1967 he sailed to Christmas Island in the Indian Ocean to study the then unknown, jungle tree-top nesting Abbott's booby which breeds nowhere else in the world, and the brown booby.

He also examined the colony of Australasian gannets at Cape Kidnappers, New Zealand. He produced a 1,000 page monograph on the world's gannets and boobies.

Other books include a volume on the Pelecaniformes and one on the biology and ecology of seabirds.

His 2013 book, On The Rocks, was an illustrated memoir of his life spent researching sea birds all over the world.

He previously said his most proud achievement was his giving of evidence to a government committee in Canberra that helped start an international outcry which led to Christmas Island being made into a National Park in 1980, giving the endangered Abbott's booby much-needed protection.