This month our regular Sunday volunteer group took a bit of a break from practical work to learn about the small mammals that call Roseberry home with the Yorkshire Mammal Group.
The previous night Area Ranger Gareth had met up with Ann Hanson from the mammal group to set the trap with the help of a couple of volunteers. This involved filling the traps with hay for bedding and a range of different food. We put in a mix of seeds, a few pieces of carrot, some nuts and some casters.
Casters are the pupae of blow flies and are essential if you are going to trap shrews. Shrews are carnivorous and need to eat their own body weight every day if they are to survive, so will starve to death if there isn’t suitable food for them in the trap. For this reason you have to get suitable training and apply for a license from Natural England if you want to trap shrews.
The following morning a large group of National Trust volunteers were joined by mammal group members to see what we had caught. The first traps we opened contained several bank voles. Voles can be told from mice by their blunter noses and small ears. Bank voles have much longer tails than their close relative, the field vole.
Ann showed us how to handle the voles by gently picking them up by the scruff of the neck. She then put them into a plastic bag so they could be weighed before releasing them. The voles seemed remarkably tame and didn’t mind being handled too much. Some even sat on the palm of people’s hands for a moment or two before scampering off into the undergrowth.
As we continued to check the traps there was an opportunity for everyone to have a go at opening a trap and handling a bank vole. We also trapped a few common shrews. These much smaller mammals which weigh only a few grams are not handled as they have very sharp teeth. Instead they were just popped into a bag for weighing before release. Strangely we didn’t find any wood mice in our traps, despite them being a common small woodland mammal. Ann told us that this year seems to be a bad year for mice and similar poor catch rates are being seen at other sites.
By lunchtime we’d checked all the traps so the mammal group headed off to leave to volunteers to do some ‘proper’ work! Many thanks to Ann for giving up her time to teach us about trapping and handling mammals.