A BLACK swan has been turning heads in Otley.
The bird has been making regular appearances on the River Wharfe, near the bridge, for the past few weeks - providing a striking contrast to the all-white mute swans that gather there.
Native to Australia, black swans were introduced to various other countries including the UK as an ornamental bird in the 1800s.
Though some have gone on to escape, the British population is not considered self-sustaining.
Nature Notes correspondent for the Wharfedale & Aireborough Observer Denis O'Connor said of the Otley bird: "It is almost certainly an escapee from a collection of exotic waterfowl.
"Black swans are native to Australia and were introduced over here as ornamental birds in the Nineteenth Century.
"Since then they have escaped and apparently formed small populations on the Thames and in Hampshire and Devon - although they are not on the official British list as it is uncertain whether these groups are self-sustaining.
"They are monogamous and pair for life with a quarter of all pairs said to be same-sex, mostly between males.
"It will be interesting to see if the Wharfemeadows Park bird stays and pairs up with a mute swan as happened a few years ago with a mute and a whooper swan, which seemed to commute between the park and Knotford Nook."
Although an unusual visitor to the town, the Royal Society for the Protection of Birds (RSPB) says sightings of black swans have become 'reasonably common' in the UK.
Posting information on its website at rspb.org.uk, the charity states that: "They can be found on almost any water body, having similar habitat requirements to mute swans and are often found in the same areas.
"They are similar in size to the closely related mute swan.
"They appear all black when swimming but they have white primary wing feathers, which can be seen in flight. The bill is red with a broad white band on the tip.
"There have been occasional reports of successful breeding attempts in the UK but they have not become established."
The species features in the traditional history stories of Australian aborigines in southern Australia.
In Europe, for some 1,500 years a 'black swan' was used as a metaphor for something that could not exist.
That changed when the Dutch explorer Willem de Vlamingh made the first recorded European sighting of the bird in 1697, on the western coast of Australia.
After black swans were brought to Europe the species was also, along with other animals like black cats, rats and crows, considered by some to be a witch's familiar and often chased or killed.