The dormouse population has suffered nationally as a result of loss of ancient semi-natural woodland, reduction in coppicing and a loss of hedgerows. As part of the Species Recovery Programme run by Natural England (then English Nature), the Lincolnshire Limewoods area was given the opportunity to take part in a national programme to reverse the decline in numbers.
32 specially reared dormice were released into Ivy Wood in 2002, following a 3-week acclimatisation in large cages, with food provided every night by volunteers. These mice were all micro-chipped, and checking all the mice found in the special nesting boxes (no chipped mice were found after 2004) quickly showed that they move much faster and further than the information available at that time suggested – and that they broke a lot more ‘rules’ as well. The books tell us that dormice are nocturnal, arboreal, and rarely come down to the ground. Ours are often very lively by day, very ready to race off over the ground, and quite quickly turned up in places they could only have got to by crossing wide, bare, open rides at ground level. They also nest happily in conifer woodland with no hazel or honeysuckle (previously thought to be ‘must-haves’) and their favourite nest site definitely has lots of bramble!
On average we find 5-6 dormice on each monthly check, spread throughout the wood, and usually handle 3-4 litters of different sizes each year. They have spread both north and south from their release wood (three ‘wild’ nests have now been found outside this area, all in bramble) and probably now inhabit an area of at least one square kilometre, perhaps more. This suggests a population of at least 100 pairs, but it might even be twice that.
Ivy Wood was chosen for the release wood partly because it provides an ideal mixture of dormouse habitats, but also because the whole Chambers block is both big, with lots of space for them to spread, and well-connected, via hedges, to a number of other woods. Through on-going research we now believe that dormice are probably at least as much at home in good, big hedges as they are in woodland, and the Limewoods area has many of these.
The next step, possibly taking place in 2012, will be to introduce another group of dormice into another of the Limewoods. If that proves as successful as the first has been, this wonderful little mammal should be securely re-established on the Lincolnshire list.