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Providing evidence to improve practice

Individual study: Reintroduction of hazel dormice Muscardinus avellanarius to Brampton Wood, Cambridgeshire, England

Published source details

Bright P. & Morris P. (2002) Putting dormice (Muscardinus avellanarius) back on the map. British Wildlife, 14, 91-100


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

Release captive-bred individuals to re-establish or boost populations in native range Terrestrial Mammal Conservation

A replicated study in 1993–2002 in seven forest sites across England, UK (Bright & Morris 2002) found that following releases of captive-bred (and some translocated wild-born) dormice Muscardinus avellanarius, populations persisted for between three months and over seven years and reproduced. In at least three of seven releases, dormouse populations were stable or increased from 19–57 released individuals to 40–55 individuals between two and seven years later. At one site, only one individual was detected 7–8 years after the release of 52 individuals in two batches. In three populations, the number of released animals is not provided, but populations persisted for at least three months and up to at least three years after release. Animals in all seven populations bred in the wild. Releases took place in 1993–2000 into woodlands in Cambridgeshire, Nottinghamshire, Cheshire, Warwickshire, Buckinghamshire, Yorkshire and Suffolk. Monitoring continued until 2000–2002. Precise numbers and origins of dormice released are not given for all sites. Most were captive-bred but some were wild-born translocated animals. Some dormice were kept in pre-release holding pens, sometimes for several weeks, before release. Nest boxes and supplementary food were provided at least at some sites. See paper for further details.

(Summarised by Phil Martin)

Translocate to re-establish or boost populations in native range Terrestrial Mammal Conservation

A replicated study in 1993–2002 in seven woodland sites across England, UK (Bright & Morris 2002) found that following releases of some wild-born translocated but mainly captive-bred common dormice Muscardinus avellanarius, populations persisted for at least three months to over seven years and all reproduced. In at least three of seven releases, dormouse populations were stable or increased from 19–57 released individuals to 40–55 individuals between two and seven years later. At one site, only one individual was detected 7–8 years after the release of 52 individuals in two batches. In three populations, the number of released animals is not provided, but populations persisted for at least three months and up to at least three years after release. Animals in all seven populations bred in the wild. Releases took place in 1993–2000 into woodlands in Cambridgeshire, Nottinghamshire, Cheshire, Warwickshire, Buckinghamshire, Yorkshire and Suffolk. Monitoring continued to 2000–2002. Precise numbers and origins of dormice released are not given for all sites. Most were captive-bred, but some were wild-born translocated animals. Some dormice were kept in pre-release holding pens, sometimes for several weeks, before release. Nest boxes and supplementary food were provided at least at some sites (see paper for further details).

(Summarised by Phil Martin)