The use of DiazaCon^TM to limit fertility in grey squirrels

The grey squirrel is an invasive alien species introduced to Great Britain in the late 19th Century and to Northern Italy during the early 20th Century. As well as displacing the native European red squirrel, grey squirrels cause significant impact to trees and woodlands through bark-stripping activity, and are implicated in the decline of woodland bird populations. In Britain, eradication is no longer an option at a regional scale, but fertility control offers a possible approach to minimise negative impacts. The cholesterol mimic DiazaConTM has been successfully used to inhibit reproduction in some species as it reduces cholesterol available for steroid reproductive hormone synthesis. Results are presented from enclosure studies investigating whether DiazaConTM would reduce cholesterol levels enough and for a sufficient period to reduce fertility in female grey squirrels.