According to a conservationist, light pollution may have driven thousands of starlings away from Belfast's Albert Bridge.
A murmuration is an aerial display that frequently drew sizable crowds to observe and take pictures.
However, the attraction has all but vanished, and it is speculated that lights on the bridge may be to blame.
The lighting, according to a Stormont department, complied with all necessary British and EU safety and environmental standards.
A group of thousands of birds swooping and diving simultaneously is known as a murmuration.
The Royal Society for the Protection of Birds (RSPB) claims that starlings do this for a variety of reasons, including banding together for warmth and security.
The starlings even made appearances on the BBC's Countryfile and The One Show because the murmuration in east Belfast had become a destination for birdwatchers.
The RSPB previously issued a warning that Northern Ireland's murmurations were in danger because of a deteriorating wildlife ecosystem.
Belfast used to be one of the best places in Ireland to see a starling murmuration, according to conservationist Conor McKinney, who spoke on Good Morning Ulster.
Climate change, among other things, could lead to displacement, according to Mr. McKinney.
"Starlings form murmurations to try to stay warm in extremely cold weather. The murmurations disappear if the winters are milder and more moderate, he claimed.
But since there are still murmurations throughout the island of Ireland and Great Britain, we can rule this out as the cause. ".
Around two years ago, the Albert Bridge's lighting was upgraded by the Department for Infrastructure (DFI) to brighter LED lanterns.
According to Mr. McKinney, studies have shown that starlings avoid roosting in areas that are overly lit.
"The physiological effects of light pollution on birds are direct. They become more stressed, exposed, and unable to fall asleep as a result," he claimed.
He claimed that the loss of the birds had "degraded the natural heritage" and "made the city a poorer place to be.".
He claimed that in order to ensure that wildlife sites were properly identified, protected, and managed, lessons needed to be learned about light pollution.
Starlings have decreased by two-thirds across the UK since the middle of the 1970s, according to Anne-Marie McDevitt of the RSPB NI, making them a red-listed species, which means they are of high conservation concern.
The murmuration, according to her, had been a natural spectacle in the middle of the city.
Additionally, she added, "roosting together in large flocks is really important for starlings because there is safety in numbers from aerial attacks from birds of prey in these large flocks, and it's thought that when starlings gather they also exchange information about vital food sources.".
She claimed that it was required by law for all government agencies to promote biodiversity.
She added that because of this and the fact that the starling is on the government's own list of priority species, any work done on or near the bridge should have taken into account the needs of starlings.
"The starlings can still return; we'd like to know how this will be accomplished.".
A representative for the Department of Infrastructure stated: "In December 2019, the street lighting on the road and footways above the bridge was upgraded to LED.
"This lighting complies with all necessary British and EU safety and environmental standards and was designed in accordance with the current British Standard, BS 5489-1:2020 Design of Road Lighting.
. "
