Colourful wild parakeets which have been spotted in Sheffield should be culled, scientists have said.
The exotic-looking immigrant birds are a threat to native species and crops, according to wildlife experts.
The bright green ring-necked parakeets have been spotted all over the UK, including Sheffield while Manchester, Liverpool and Edinburgh have also reported sightings.
In 2012, there were an estimated 32,000 in Britain but there are no recent estimates and the numbers are thought to be much higher.
Parrots have settled into Britain so well that a four-year research programme called ParrotNet was established to monitor the invasion.
The co-founder of ParrotNet, Dr Hazel Jackson, a specialist in invasive species and conservation at the University of Kent, has said the parakeets are an urgent economic, societal and environmental problem.
The group is due to present its findings to scientists at the Department for Environment, Food and Rural Affairs which may include recommendations to cull the birds.
The rose-ringed parakeet is listed amongst the top 100 worst alien species in Europe, and since the 1970s has rapidly established itself in over 100 cities across the continent and beyond.