First ever reintroduction of rare hazel dormice into the National Forest

In mid June, 38 dormice were released into a woodland at the National Trust property Calke Abbey, Derbyshire, in a bid to boost the population of this native species that has experienced a 51% decline since 2000.

The rare hazel dormice were reintroduced into the heart of the National Forest by wildlife charity People’s Trust for Endangered Species (PTES), the National Trust and partners, in an attempt to save this endangered species from extinction in the UK.

The golden-coated, bright-eyed dormice were released into a large, secluded woodland on the Calke Abbey estate in Derbyshire, cared for by the National Trust, as part of ongoing conservation efforts to return hazel dormice to areas where the tiny mammals are locally extinct.

Despite once being a common feature of the UK’s woodlands, hazel dormouse numbers have plummeted in recent years due to habitat loss and fragmentation, and climate change. According to PTES’ State of Britain’s Dormice 2019 report, nationwide populations declined by a staggering 51% since 2000 and dormice are considered extinct in 17 English counties. PTES and partners release healthy, captive bred dormice every year into well managed woodlands across the country to try and combat this decline. Since the programme began in 1993, 1,078 dormice have been reintroduced to 25 different woodlands in 13 counties.

Led by PTES since 2000, the annual reintroductions are part of Natural England’s Species Recovery Programme and the reintroduction is the culmination of months of hard work by several partner organisations, including the Common Dormouse Captive Breeders Group including Wildwood Trust, Paignton Zoo and ZSL.

Ian White, Dormouse & Training Officer, PTES says: “The ongoing success of our annual dormouse reintroductions is the result of a unique partnership and many passionate volunteers who together work tirelessly to help us bring dormice back from the brink and ensure their ongoing survival. Well-managed woodlands and hedgerows are key to restoring dormouse populations across the UK, so releasing dormice into such habitats is crucial for the species’ long-term recovery. The National Forest is home to a huge array of woodlands suitable for dormice, so we hope that this is the first of many reintroductions to take place in this part of the country.”

The National Trust’s ranger team and a group of volunteers will be responsible for the ongoing care of the dormice and long-term management of the woodland after the reintroduction has taken place.

This year, all dormice released are captive bred by the Wildwood Trust, a member of the Common Dormouse Captive Breeders Group, before they undergo an eight-week quarantine and receive full health-checks by expert wildlife vets at Paignton Zoo and ZSL’s Disease Risk Analysis and Health Surveillance (DRAHS) team. Regular health screening ensures that only healthy dormice are released into the wild, and the dormice harbour only native parasite species of importance to biodiversity, both of which are vital in mitigating against disease.

After reintroduction day, the dormice are left to quietly acclimatise to their new surroundings from the safety of their nest boxes, which are gently placed within larger mesh cages filled with foliage, food and water. Local volunteers will top up their food and water daily, and after 10 days, and a further health examination, the mesh cage doors are opened to allow the dormice to explore their new home. When the dormice no longer use the mesh cages, they will be removed, leaving the dormice to live freely in the woodland. Slowly the dormouse population will increase and in time they will start to disperse to new woodland and hedge areas.

To find out more about PTES’ dormouse conservation work, visit www.ptes.org/dormice