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Providing evidence to improve practice

Individual study: Effects of pre-release health, release time and translocation method on water vole Arvicola terrestris survival at Barn Elms, Greater London, England

Published source details

Mathews F., Moro D., Strachan R., Gelling M., & Buller N. (2006) Health surveillance in wildlife reintroductions. Biological Conservation, 131, 338-347


This study is summarised as evidence for the intervention(s) shown on the right. The icon shows which synopsis it is relevant to.

Use holding pens at release site prior to release of captive-bred mammals Terrestrial Mammal Conservation

A review of a study in 2001–2002 at a restored wetland in London, UK (Mathews et al. 2006) found that using holding pens prior to release of captive-bred and translocated water voles Arvicola terrestris resulted in greater post-release survival than did releasing them directly into the wild. Voles released from pens were three times more likely to be recorded during the initial follow-up survey than were those released without use of pens (result presented as odds ratio). A total of 109 captive-bred and 38 wild-caught water voles were released in groups of 6–15 animals in May–July 2001. Prior to release, no water voles were present at the site. An unspecified number of animals were placed in an enclosure with food and shelter and allowed to burrow out at will. The remainder were released directly into the wild. Animals were monitored by live-trapping over three periods of five days, between autumn 2001 and early-summer 2002.

(Summarised by Phil Martin)

Use holding pens at release site prior to release of translocated mammals Terrestrial Mammal Conservation

A review of a study in 2001–2002 at a restored wetland in London, UK (Mathews et al. 2006) found that using holding pens prior to release of translocated and captive-bred water voles Arvicola terrestris resulted in greater post-release survival than did releasing them directly into the wild. Voles released from pens were three times more likely to be recorded during the initial follow-up survey than were those released without use of pens (result presented as odds ratio). A total of 38 wild-caught and 109 captive-bred water voles were released in groups of 6–15 animals in May–July 2001. Prior to release, no water voles were present at the site. An unspecified number of animals were placed in an enclosure with food and shelter and allowed to burrow out at will. The remainder were released directly into the wild. Animals were monitored by live-trapping over three periods of five days, between autumn 2001 and early-summer 2002.

(Summarised by Phil Martin)