Millions of starlings created a 'twitter storm' as they flocked together over the skies of Gretna.

The birds put on a mesmerising performance as they wheeled and swooped in unison at dusk - creating dark shape-shifting clouds.

They have come to roost this November, creating a swirling spectacle which attracts tourists to the town and impresses the locals.

The fantastic display is known as a 'murmuration' and the starlings normally head to Gretna, near the Scottish border, in November.

Over summer there are 170,000 to 300,000 breeding pairs but over winter the Scottish population of starlings swells to two million to three million.

The birds will stay until February before flying back to continental Europe for the spring and summer.

Neil O'Donnell, of the RSPB in South and West Scotland, said: "When the breeding cycle is over for the year, starlings come to Britain from the continent because it is so cold on mainland Europe.

"They form these special flocks in the sky if predators are around.

"The birds are better off being in a massive flock, as this confuses the predators and also there are more eyes to look out for danger.

"During the day the birds go out to feed, then they all come back to roost in the evening.

"They feel a lot safer roosting together. They take to the sky and form a murmuration.

"The starlings base their movements on the birds around them and so this is why you do not see them bump into each other.

"The birds form a cloud in the sky, and appear to move as though they were a single being.

"Large groups of starlings confuse predators as they do not know which bird to go for."

Mr O'Donnell added that Gretna is a popular place for bird watchers to come at this time of year.

He said: "Gretna is probably the best place to watch the murmuration.

"The roads leading off the M6 motorway towards Gretna are full of cars at this time of year, with people gazing at the sky to see the birds, it's a marvellous spectacle and great to see.

"The number of starlings travelling to Britain each year fluctuates.

"The murmurations can be formed by hundreds of thousands or even millions of the birds, there can be massive numbers.

"The numbers depend on how harsh the winter is on mainland Europe."

Iain Broughton, manager at the Solway Lodge in Gretna said: "The starlings are on time this year as normal. They usually arrive in November and people come from all over the country to see them.

"I guess it is normal for us now living in Gretna, but there are swarms of them flying together at dusk, they're in all the bushes and the trees. It's great for tourism."