Wildlife experts from the region say research into the effects of gamebirds is required.
Wildlife experts across the region have backed calls for a detailed assessment of the impact the release of millions of gamebirds for shooting is having on native species.
According to recent research by Thetford-based British Trust for Ornithology (BTO), every year 41 to 50 million non-native gamebirds, predominantly pheasants and red-legged partridges, are released across the UK. Fewer than half these birds are shot, meaning there is potentially a large food resource available to predators and scavengers, sustaining their populations above the levels they would otherwise reach.
The issue has been brought into sharp focus by wildlife campaign group Wild Justice, which is launching a legal challenge against the Government over "failures" to assess the impacts of the practice. The group claims the numbers of captive reared pheasants and partridges being released have increased about 10-fold in the last 45 years and are not regulated by the Government, with more paperwork needed to reintroduce native British species as part of conservation plans than game birds.
Scale
Head of conservation at Suffolk Wildlife Trust, Ben McFarland, said there is a need to better understand better this impact.
He said: "It is definitely an issue ecologically. There needs to be more research about the impact, especially when they are released in large numbers or near areas bordering land of high value [nature reserves]."
Mr McFarland stressed his comments should not be taken as being anti-shooting but he said: "Pheasants can take reptiles, snakes especially, and cause damage to amphibians. It's difficult to know the scale of the ecological impact they cause and it will depend on the type of habitat where they are."
Origins
The red-legged partridge was brought to the UK from continental Europe, where it is largely found in France and Spain, while the common pheasant originates from China and East Asia but was introduced centuries ago with records going back to Roman times.
Head of people and wildlife at Norfolk Wildlife Trust, David North, said it was likely that the release of such large numbers of birds into the Norfolk and Suffolk countryside will have significant impacts on other wildlife.
He added: "It is likely that pheasant rearing leads to an increase in ground predators, both rats which benefit from the provision of grain used to feed pheasants and foxes which feed on easily available dead pheasants killed on roads and also the easily predated young pheasants soon after their release.
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Snakes and slow worms
"In addition, populations of birds such as carrion crows and magpies are likely to benefit by feeding on road-killed pheasants and partridges. Adult pheasants are also known to predate slow worms, young grass snakes and adders, and this may be one factor in the widespread decline of these species. Further research is certainly needed to better understand these possible impacts."
Chief executive of the Game and Wildlife Conservation Trust (GWCT), Teresa Dent, told the Press Association: "The GWCT has carried out detailed research that measured the effects of released pheasants and red-legged partridges on other wildlife and wildlife habitats.
"We found that the releasing of lowland gamebirds can be done in a way that minimises or avoids negative effects on habitats and other wildlife, and maximises the potential of management practices associated with releasing to deliver broader biodiversity benefit."
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