A photo of a starling murmuration doubling as smoke from a chimney has been called a "fluke" by its photographer.
Anna Tosney was walking home on Friday evening in Skipton, North Yorkshire, when thousands of birds appeared.
The town has become a hotspot for murmurations in recent weeks, with regular sightings since early January.
Miss Tosney, from Skipton, described watching the natural phenomenon as "amazing and addictive".
The printmaker had already witnessed multiple murmurations near her home, but luck had not been on her side in her previous attempts to get a photo.
"I've been trying for days and days and either my battery has died or my baby has been crying, then they appeared when I wasn't even looking for them," she said.
Her image was taken on her camera phone at about 17:30 GMT while she was walking along Gargrave Road.
- They are thought to be formed as birds try to protect themselves from predators, keep warm and exchange information.
- Starling numbers swell in autumn and winter due to the birds migrating across from Scandinavia and elsewhere in Europe to spend the colder months in the UK.
- The word "murmuration" comes from the sound that thousands of wings make as they beat simultaneously.
- Starlings can react to each other's movement in less than 100 milliseconds (as opposed to the average human reaction time of 215 milliseconds), so they avoid collisions.
- The number of starlings in a roost can swell to more than 100,000 in some places.
- Early evening, just before dusk, is the best time to see them across the UK.
Miss Tosney said: "I could see there was a big area of sky and the chimney was there, so I took a series of photos.
"When I looked back, in one of them they were coming out of the chimney and looked like smoke, it was quite cool.
"I'd like to think it was particularly well planned, but it was a fluke," she added.
The Yorkshire Wildlife Trust (YWT) said Skipton may be a good area for sightings due to geographical and ecological factors.
India Ashfield, YWT environmental youth leader, said: "Starlings aren't too fussy about their habitat, but the Yorkshire Dales is a prime spot to see murmurations as it has everything the birds require.
"Skipton is surrounded by open grassy areas and farmland for foraging, water sources, trees and buildings for nesting areas and the town itself is quite sheltered."