21 Jul 2013

Voles, Mice and Shrews

Ardd Fotaneg · Botanic Garden

Over the previous weekend Michael, with the aid of Iwan, Cameron and Simon,  had been setting up Longworth small mammal traps in various places around the Garden.  They were baited to start with but left open as the idea was to get the animals used to them.  These lightweight aluminium traps are  designed to capture small mammals with the minimum of discomfort to the animal.  They consist of two parts: a tunnel which contains the door tripping mechanism, and a nest box, which is attached to the back of the tunnel. The nest box provides a large space for food and bedding material to ensure that the trapped animal is comfortable until release.  Once the traps are baited – with hamster food – they need to be checked every 12 hours otherwise any animals trapped may die.

[nggallery id=398]

Michael checked and rebaited the traps on Sunday and rebaited and released the trip mechanism on Monday so they were ready for us all on Tuesday for the morning group was to examine them.  The big prize was to find a Yellow-necked Mouse.  These are similar in appearance to wood mice who they are closely related to, but can be distinguished by a yellow spot that extends sideways to form a collar. They are also slightly larger than wood mice.  In Britain, they are concentrated around the Welsh borders, the western Cotswolds and south-eastern counties.

This week we were again joined by a work experience lad, Osian Morgan, together with Jan, Michael, Howard, John, Chris and partner from Swansea Met, and Hannah.  The first point of call was the lane next to Trawscoed meadow near where the Dormice nest boxes had been set up.  Examination of the latter revealed nothing, not even any moss, but we were luckier with the traps which had been set up in groups of three as one in each of the groups contained an animal – a Bank Vole, a Pygmy Shrew and a Wood Mouse.

[nggallery id=397]

The Bank Vole is a lovely little creature which can be fairly easily distinguished from a Wood Mouse as it has a slightly reddish tinge on its back.  They are also diurnal so have smaller eyes than the Wood Mouse – larger eyes mean more light gathering power and indicates a nocturnal existence.

On to the next set of traps behind the greenhouses and near the woodpiles and stumpery.  Here we found 3 more Bank Voles. They take to traps very easily as they know where the food is and will go back in again after having been trapped, but these were different ones.   They are also tameable, quite liked being stroked and make very good pets, except that they don’t live very long – maybe 8 or 9 months.

The final set of traps were up behind the Science block and involved a rather prickly ascent up the hill.  On our last visit there had been a path, but this had become very overgrown, and the patch where the traps were set – near the other set of Dormice nest boxes – had been completely covered with nettles – they had to be cut down the previous weekend.  Alas nothing in any of the traps or the nest boxes, so back down the hill and off to the restaurant for the usual tea and chat.  Along the way we did find another Common Shrew, unfortunately dead, and plenty of evidence of Rabbits in the form of their droppings.

Subsequent to this in the evening and the following morning, Michael continued to monitor the traps and these resulted in a further 2 Bank Voles in the evening and 3 on the Wednesday morning. They really do know what’s good for them!  No Yellow-necked mice though.

An especial thanks to Michael for his work in setting up and monitoring these traps.  It was a splendid opportunity for the rest of us to get close to these animals in a way which is not usually possible.

Thanks to John for his photos and if any volunteer or member is interested in joining us, or even starting something similar on a different day please  send an email to Colin Miles  – you DON’T have to be an expert in anything, just interested.   If you click on any of the images in these blogs, or anywhere else you will see a larger picture. And if you click on the Wildlife Walks heading on the left-hand side under News you will see a list of the last 10 Wildlife Walk blogs.