A project to boost red squirrel numbers in the Larne area has "questionable ecological value", a London-based campaign group has claimed.
Last month, Ballygally Biodiversity Group outlined plans to return the red squirrel to Carnfunnock Country Park and Chaine’s Wood.
The project is seeking public feedback on sightings of the under-threat species, whose numbers have decreased sharply in recent years.
However, concerns were raised by London-based Urban Squirrels, which campaigns against "cruel and unnecessary culls and [promotes] non-lethal conflict resolution".
In the letter to the Larne Times, Natalia Doran from the group queried the "ecological value" of the project.
"Red squirrels are undeniably cute, but boosting their numbers in Larne has very questionable ecological value. The issue is especially worrying because extensive culling of grey squirrels is made an integral part of the process," Ms Doran wrote.
"Red squirrels do struggle in the UK, where the habitat is no longer suitable for them, due to deforestation. But nature can be surprisingly good at dealing with the ecological mess we create, and the role in the habitat that was formerly played by red squirrels is now successfully played by grey squirrels, who, although an introduced species, are a better ecological fit in the conditions that exist today.
"Describing grey squirrels as 'an absolute menace' and not 'our own' is hardly the language of evidence-based conservation. And the evidence actually absolves grey squirrels of the accusations levelled against them. For example, an extensive government-funded monitoring programme concluded that grey squirrels do not reduce the bird population. A Forestry Commission study also absolved them of "destroying" managed woodland. And let us not forget that at the time when red squirrels were numerous they were accused of exactly the same things as their grey cousins are accused of today. This is the 'logic' of prejudice, not conservation.
"When two species have the same ecological impact, preferring one to the other to such an extend as to start massive culls is not a rational approach in conservation and should be abandoned as soon as possible.
"If people like red squirrels and want to preserve them, they should look for non-violent means to do so and not try to present their sentimental preference for 'our own' as a conservation imperative."
Responding, BBG Secretary Joe Dowdall said: "The red squirrel population has been wiped out in Southern England and Wales over the past 30 to 50 years. In the Northern Ireland we still have the native red squirrel and we will do our best to protect and maintain it throughout our woodlands.
"It lives well in mixed woodland as long as it is not starved out by the invasive grey squirrel and then infected with squirrel pox, which the grey carries and is immune to; this kills the red within 10 days.
"There is much evidence of grey squirrels destroying broods of nesting birds and local evidence of an increase in bird population when greys are removed. This is not fiction; the local people know and have witnessed this happening.
"Red squirrels are protected by law, are a part of the natural structure of the woodland, do contribute to the spread of our native trees and scrubs and have a place in a balanced habitat. Grey squirrels are described officially as an 'alien and invasive species' and are detrimental to our native species. They were 'introduced' and were allowed to run out of control across the UK.
"For the red squirrel to survive the grey has to be controlled."