Written question asked by Lord Hart of Tenby (Conservative) on Monday, 17 October 2011, in the House of Commons. It was due for an answer on Wednesday, 19 October 2011. It was answered by Lord Benyon (Conservative) on Tuesday, 1 November 2011 on behalf of the Department for Environment, Food and Rural Affairs.

Squirrels: Pest Control

Question: To ask the Secretary of State for Environment, Food and Rural Affairs what research her Department has (a) commissioned and (b) published in relation to immune contraception as a means of controlling grey squirrels; and what the cost to the public purse of such research has been.

Answer: Work on immuno-contraception in grey squirrels by the Forestry Commission's agency Forest Research ended in 2006-07. Field trials failed to produce an immune response that was powerful or long-lasting. Attention has now turned to another compound called DiazaCon which has shown promise as a fertility control agent. 'Proof of concept' enclosure studies between 2007 and 2011 confirmed an effect of DiazaCon on squirrel blood chemistry but the effect on reproduction was inconclusive. Further research is also needed to refine species-specific field delivery systems.Information on immuno-contraception was last reported in Forest Research's Annual Report and Accounts in 1999-2000.Results from the recent enclosure studies of the use of DiazaCon were presented at the 8th International Vertebrate Pest Conference in 2011. The proceedings are due to be published in Pest Management Science early in 2012.The cost of the studies on immuno-contraception totalled £323,000 during the period 2002-07. They were funded by the Forestry Commission, DEFRA, the Countryside Council for Wales, Scottish Natural Heritage and Natural England. A total of £282,000 has been spent on studies using DiazaCon from 2007-11 by DEFRA and the Forestry Commission.

Secondary information