§ Sir Nicholas WintertonTo ask the Secretary of State for Environment, Food and Rural Affairs what assessment she has made of the geographical incidence of grey squirrels in England; and what data is held by her Department on the spread of populations of grey squirrels since the species' introduction. [178082]
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§ Mr. Bradshaw[holding answer 10 June 2004]: The first documented release of grey squirrels into the UK was in 1876 in Cheshire, with subsequent introduction to sites ranging from Glamorgan to Kent totalling more than 350 individuals. Grey squirrels are now present in every English county and absent only from parts of Cumbria and Northumberland, a small area of the Sefton coast, the Isle of Wight and Poole harbour islands.
Numbers of grey squirrels fluctuate considerably between years. However, the population was estimated at 2.5 million in the 1990s and it is likely to have increased since then as their range has expanded. Through the Tracking Mammals Partnership, funding has been secured from both Joint Nature Conservation Committee and Peoples' Trust for Endangered Species for a scoping study to investigate monitoring strategies for squirrels to address these issues.
§ Sir Nicholas WintertonTo ask the Secretary of State for Environment, Food and Rural Affairs what assessment she has made of the effect of grey squirrels on indigenous flora and fauna; and what recent research studies into the ecological effects of grey squirrels her Department has carried out. [178083]
§ Mr. Bradshaw[holding answer 10 June 2004]: The impact of the introduced grey squirrel on the native red squirrel is well known. Since the beginning of the 20th century, the spread of the grey has been closely linked with the decline and disappearance of the red squirrel from most of England. Although the two species may co-exist in some areas for many years, it seems that sooner or later the greys will dominate and the reds disappear. The exact mechanism for this replacement is not entirely clear; some recent work confirms the importance of interspecific competition, but a disease, parapox virus, which is harmless to greys but fatal to reds, may also be involved.
Squirrel presence surveys carried out by the Forestry Commission since the 1950s recorded the presence of bark stripping damage to individual tree species in woodlands. During 2000 a survey of private and state owned woodlands within the distribution range of grey squirrels in Great Britain further investigated damage levels by recording damage severity. Current studies are investigating the effect of grey squirrel bark stripping damage to oak in terms of tree growth rates.
The review "Possible effects of grey squirrels on birds and other wildlife", published in British Wildlife in February 2004, reviewed evidence of predation published in British Wildlife in February 2004, reviewed evidence of predation by squirrels on birds' eggs and nestlings, potential competition with birds for nest sites and food and competition with native mammals. Possible effects on woodland structure through their bark stripping activities and as a predator of tree seeds and bulbs were also considered.
§ Sir Nicholas WintertonTo ask the Secretary of State for Environment, Food and Rural Affairs what assessment she has made of the effect of grey squirrels on the geographical incidence of the indigenous red squirrel population in England. [178084]
§ Mr. Bradshaw[holding answer 10 June 2004]: Historical data show red squirrels to have been ubiquitous throughout England until the 1920s. Since 954W the grey squirrel was released in the late 19th and early 20th century and their subsequent spread, the red squirrel has suffered a concurrent range contraction.
The red squirrel seems to have made some small gains in the Yorkshire Dales, where it has been able to expand into plantations that are now maturing and producing good crops of the pine cones that it needs.
The continuing expansion of the grey squirrel is to be expected and red squirrel conservation is focused on limiting that expansion in areas where the two species overlap. Some significant progress has been made in developing more effective and targeted ways of defending healthy populations of red squirrels against replacement by the grey squirrel.