David Carroll had a tough time at school.
He moved from school to school as child as his dad's job took him around different parts of the country as circulation manager for several different newspapers in the 1950 and 60s.
But by the time he was 10, he was living in Doncaster, and in the 1960s he become one of the first pupils to go to Ridgewood School when it first opened.
David believes moving around from school to school affected his education, and as a result, he left school with few qualifications.
But he impressed bosses at the Doncaster Plantworks - the huge railway site in Hexthorpe where locomotives such as Flying Scotsman and Mallard were built in the 1920s and 30s.
They offered him a job, which saw him mix work with a day a week at Doncaster College of Technology - a college site near Waterdale.
David remembers it as a time when Doncaster was a hive of industry and engineering, and he enjoyed his job at the plantworks, with what was then British Rail.
He said: "I was delighted to get that job after leaving school. The time at college improved my education, I had some stability and I was happy, There was a lot of camaraderie and banter, although it was pretty male dominated in those days.
"I was a diesel engineer by trade, a fitter doing mechanical work. We built new trains, class 56 and 58 freight engines, but my work was in repair and maintenance."
But he decided to leave the industry in 1994, wihen the industry was denationalised. David took voluntary redundancy, and planned to take a degree at High Melton College.
He had planned to take a BA in social science. But he ditched those plans when he saw an advert in the Doncaster Free Press for a job as warden at Potteric Carr Nature Reserve.
He applied and was given the job, abandoning his plans to study for a degree.
For David, it was his ideal job. He felt himself to be an amateur naturalist, and had a keen interest in wildlife and nature since childhood.
He had loved watching birds as a teenager, and had been a member of the Yorkshire Naturalists Trust, encouraged to join by Roger Mitchell, who was the president of the Doncaster and District Ornithological Society. He'd also done voluntary work at Denaby Ings and Sprotbrough Flash nature reserves.
His new job involved looking after the site, using many of his engineering skills, and he met a string of celebrities during his time there including Sir David Attenborough and the comedian Bill Oddie.
But after 14 years in the post, his life was thrown in the air again.
He was at home in Cusworth in 2005, when he started to feel chest pains.
"I came out in a cold sweat and I thought I was about to pass out. I was having a heart attack, at the age of 51, and it came completely out of the blue. I called and ambulance and it was there within five minutes.
"They rushed me to hospital. They put stents in and I had an operation. I had three blocked arteries.
"The NHS were fantastic, and the rehab they gave me was fantastic, although I'm on medication for life now."
With the shock of his heart attack, David decided to go to part time work. Then a couple of years later, he gave up his job and sold his house to give himself and income. He now lives in in Adwick.
He remained as a volunteer at the nature reserve, and did freelance work when he could.
"The heart attack was a life changing event," he said. "I was lucky to be able to sell my property.
"In a way it has worked in my favour, and I've enjoyed semi-retirement, and I've not had any problems since.
"I walked the Pennine Way in 2015, but in sections over time, rather than doing the whole thing in one go."
This year David, now aged 65, was rewarded for this voluntary work. He was invited to a garden party at Buckingham Palace when the Yorkshire Wildlife Trust was recognised with the Queen's Award for Voluntary Service.
"I didn't get to to speak to the Queen, but I was very close to her," he said. "I first heard about it in April but had to keep it secret until June. It was a great privilege, and it was great to represent the nature reserve."