RISING temperatures are attracting a new species of bird to move north and breed in the Lothians for the first time.
The Lothians and the Scottish Ornithology Club has this year recorded two reports of the nuthatch nesting in trees.
Officials at the organisation today said there had been further sightings of the bird in parts of Edinburgh - including Corstorphine Hill and The Meadows - although the only known places where the bird has been nesting in the area were near East Linton, East Lothian, and Roslin in Midlothian.
David Kelly, the club's Lothian recorder, said the nuthatch seemed to be inching north. "It's a new species we know is now breeding in the Lothians."
"The nuthatch has been found breeding in Midlothian this year and was seen for the first time in East Lothian last year and again this year. It is quite significant because the likelihood is that it is connected to global warming.
"They are small birds, blue and white in colour with a black mask - maybe slightly bigger than a blue tit.
"They were breeding for the first time in Scotland in 1989 and although there has been a few sightings, they haven't been breeding in the Edinburgh and Lothians area until now."
He added: "I would expect them to come into Edinburgh more and people should look out for them.
"They have interesting habits, such as running up and down tree trunks, and it nests in a hole which it breaks up with mud so no other bird can get in or out. That is quite unusual." Other birds which appeared to be moving north, he added, included the hobby, a bird of prey, and little egrets - with global warming again thought to be the contributory factor.
Nature and wildlife expert Archie Mathieson, a former East Lothian countryside ranger, said it was the first he had heard of the nuthatch nesting in the area.
"There have been one or two reported sightings I have heard about," he said. "They seem to be spreading up from the Borders. I had a very good photograph taken of one on an estate between Gifford and Haddington. Until now I haven't heard of them nesting but if there is enough of them it is inevitable that they will nest.
"It's very interesting to hear about this and I'm sure many people will be eagerly looking out for it when they go bird-watching.
He added: "I used to see them in Hertfordshire when I worked down there for a couple of years but I think I have only seen maybe one up here with my own eyes. They are nice wee birds, very eye-catching."
A spokesman for the RSPB said: "They are steadily making their way towards the central belt from Northumberland because of the warmer weather. They are regularly seen in the Lothians now and are inching their way further north. Whether or not they are breeding is another matter."
• At first glance, the nuthatch looks rather like a woodpecker. It is a pretty, plump-looking bird with a pointed bill and a short, square tail. It also has a slate-grey back, chestnut flanks, a buff breast and bold black eye-stripes.
Unlike woodpeckers, the nuthatch can move down tree trunks head-first as easily as in other directions.
They are agile birds and can easily hop upwards on a tree trunk, picking out insects on their way. While widespread and fairly common in England and Wales, the birds have been largely absent from Scotland and Ireland. Nuthatches build their nest in a tree hole, and sometimes plaster the hole with mud if it is too large. Females lay between six and nine eggs during April and May.
Sightings are most common in woodland areas, hedges, at the peanut feeder and birdbath.