Ornithologist and gannet expert

Born: March 14, 1932.

Died: June 29, 2015.

DR BRYAN Nelson, who has died aged 83, was a passionate zoologist, ornithologist and wildlife enthusiast whose studies and work around Scotland and beyond bought him a reputation as the world's leading expert on gannets.

Always accompanied by his equally-intrepid wife and fellow-researcher June, he studied gannets and other seabirds on remote islands from Scotland's Bass Rock on the outer Firth of Forth to the Pacific Galápagos Islands made famous by Charles Darwin.

Later, using colourful body language which lit up his classes, he would vividly communicate his findings to his rapt students at Aberdeen University. His 1,000-word 1978 monograph on gannets is globally respected as are his studies of Pelicaniformes, the group of water birds including pelicans, cormorants and frigatebirds.

Former student Tom Brock said Dr Nelson was an extraordinary teacher. "When talking about 'skypointing' (when, for the chicks' safety, a gannet signals to its partner that it is about to leave the nest) he didn't just show a photo," said Mr Brock. "He became a gannet, using his whole body to imitate that distinctive posture of the gannet - unforgettable!

"When he talked on the call of the kittiwake (gull), his wonderfully accurate imitation echoed at great volume around the lecture theatre. He was fascinated by animal communication and became a wonderful human communicator to pass it on to the world." His classes, all agreed, were a joy to attend.

Mr Brock, who is now chief executive of the Scottish Seabird Centre at the Harbour, North Berwick, where Dr Nelson was a special advisor and past board member, also remembers Dr Nelson's imitation of gannets beak-fencing, when two mates have a friendly but frenetic fencing match to demonstrate their bond. Northern gannets are the largest seabirds in the North Atlantic, often with a wingspan of over six feet. They can dive-fish from 100 feet above the water, hitting around 75mph and "aquatic flying" deep below the surface to catch a snack (lots of snacks, hence the expression "eat like a gannet.") The Bass Rock - for a long time almost a second home to the Nelsons - is home to the world's biggest colony of Northern gannets (Morus bassanus), their colour often making the island look white from the mainland.

One of Dr Nelson's proudest achievements was pressing the Australian government into making Christmas Island (an Australian territory in the Indian Ocean) into a National Park, largely to save an endangered bird, the Abbott's booby which nests only on the island. Concerned that phosphate mining could destroy the species, Dr Nelson appealed to the Canberra government and started an international outcry among environmentalists.

Joseph Bryan Nelson was born in the textiles town of Shipley, West Yorkshire, on March 14, 1932, the third of four children. He attended the nearby Saltaire Grammar School but left at the age of 16 to help keep his family. His father had run off to sea a few years earlier.

Young Bryan first worked at a sewage purification plant in Esholt near his home, while continuing his school studies at night school. Hard work got him a place at St Andrews, where he got a zoology degree followed by a D Phil from Oxford.

While at Oxford, he spent his spare time birdwatching, running a Methodist church Sunday school, preaching and visiting hospitals. He married June Davison, a tax office worker from Rawdon, Leeds, in 1960, and they would spend the next 55 years together, at work and play, which they tried to combine.

"We sort of met under a table sheltering from the rain at Spurn Point (on the Humber estuary in the East Riding of Yorkshire)," said June, "watching and ringing birds on migration. I offered him half my apple which he reluctantly accepted."

The couple honeymooned on Bass Rock and from 1960-63 lived there in a garden shed (built with the help of their only neighbours, the lighthouse keepers) that sat eerily within the ruins of the sixth century St Baldred's chapel. The hut was held down by hawsers against the powerful winds and uninsulated. They survived through body warmth.

At the end of 1963, they took off across the world to the Galapagos Islands off Ecuador to study frigatebirds and boobies of the masked, red-footed and blue-footed varieties. Hearing of this intrepid British couple, the Duke of Edinburgh ordered the Royal yacht Brittania to stop and he went ashore. He agreed to take many of their notebooks back to the UK and invited them on board. Dr Nelson recalled looking a bit like Robison Crusoe as they boarded the famous vessel - "barefoot with patched-up shorts covered in albatross vomit."

He and June also worked at the worryingly-named Cape Kidnappers, New Zealand, studying gannets, and in Jordan to study migrant birds at a desert oasis.

He wrote many papers and several books, including the brilliant On the Rocks, published last year with artwork by Dr Nelson's friend the wildlife artist John Busby, who died earlier last month.

Dr Joseph Bryan Nelson, FRSE, MBE, had suffered gradually from a genetic heart defect. He died at his home in Kirkcudbright, where he and his wife had recently moved, through health necessity, from a suitably remote house on a farm track in Galloway. He spent his last few days listening for cuckoos but "sadly he didn't hear any this year," his wife June said. His three siblings predeceased him.

He is survived by June, their son Simon and daughter Becky, both of them following their parents' adventurous tradition, and two grandchildren. Dr Nelson's "green burial" will be at Roucan Loch outside Dumfries on Monday July 20.

PHIL DAVISON