A bird of prey spotted flying over Larne Lough has been confirmed as the first sighting of the rare Montagu’s harrier in Northern Ireland.

And the birdwatcher who caught sight of the harrier believes climate change may have played a part in bringing it to more northerly climes.

It was initially thought that the bird was a female hen harrier, but, thanks to video footage taken by birding enthusiast Cameron Moore, the Northern Ireland Rarity Committee has just confirmed that it was a female Montagu’s harrier.

Mr Moore was initially told by another birdwatcher that the bird couldn’t be a Montagu’s harrier as it doesn’t occur in Northern Ireland – but some nagging doubts remained.

Eventually he submitted the footage to the Northern Ireland Rarities Committee, which came to the conclusion that it was indeed a female Montagu’s harrier – the first to appear in Northern Ireland.

“It has to be 100%. Four or five people on the committee study the footage and if they are not 100% on that bird, it’ll not pass,” he said.

Mr Moore, from Whitehead, never goes birdwatching without his camcorder and it proved to be a valuable tool when he learned from his friend Keith Glasgow that a bird of prey had been spotted in Magheramorne, heading towards Ballycarry Bridge.

“I decided to investigate this sighting and arrived at the bridge to see three hooded crows harassing a harrier,” he said.

Mr Moore wasn’t close enough to make an identification but the following morning he and his friend Joe Lamont went out to search for the mysterious predator.

“On arrival at the bridge we spotted the harrier hunting at the south end of Larne Lough,” he said.

“In order to get a better view of the bird we made our way down a lane at the top end of the lough and again spotted the bird hunting. At this point I started to video record what I believed to be a female hen harrier.

“I stated to Joe that the wings were too long and it flew in too strange a manner to be that of a hen harrier. Joe agreed and asked why a hen harrier would be on low ground at this time of the year.

“The bird stayed in view for around 15 minutes and then flew into a wooded area and out of sight. When I returned home I viewed the footage and my instincts said that this was a Montagu’s harrier.”

Montagu’s harrier is known as Britain’s rarest breeding bird of prey, travelling north in summer to breed in southern and eastern England – the northern edge of its range, which stretches down through northern Africa.

“The Montagu’s is a little smaller than our common buzzard and has a wing span between 100cm and 120cm and is dark brown in colour,” Mr Moore said. “The upper wing has a dark line along the secondaries, its tail is long and has a series of bands with a white rump. They eat small birds, rodents and rabbits.”

The birds may be starting to appear further north because of climate change, he said.

“As the temperature goes up, they are getting pushed further and further north. There are things happening – it’s definitely global warming that is pushing them further north,” he said.

The harrier is not the only rare bird Mr Moore has spotted. In January this year he was walking with his grandson along the shore in Whitehead when he caught sight of a rare Bonaparte’s gull, a bird native to Canada.