A St Andrews University student is shedding light on the secret life of small mammals in arable farmland
Amanda Wilson is being mentored through her PhD by the GWCT’s Dr Dave Parish and is investigating how small mammals use arable habitat within Tayside. Amanda is a joint student between the University of St Andrews and the James Hutton Institute in Dundee, where she is being supervised by Dr Brian Fenton, Dr Graham Begg and Professor Steve Hubbard.
A bank vole about to be released back into the field. This is one of three species of vole
present in Scotland. Water voles are much larger. Field voles have very short tails in
comparison to bank voles, which have a tail that is approximately half the length of their
body. Bank voles are also more chestnut brown in colour than field voles.
Research into the impact of small mammals within agricultural systems has been traditionally lacking. Nevertheless, they may play an important positive or negative role in achieving sustainable agriculture, by consuming weed seeds, for example. They are an abundant and common environmental resource and provide a food source for rare and threatened birds of prey and larger mammals. They may also compromise food production, especially at high densities, by consuming crops.
“We have been combining molecular genetics with live trapping to investigate habitat use by individuals at different stages of the growing season,” explained Amanda, who has captured hundreds of wood mice and extracted DNA from their hair. This information can be used to identify positions where unique individuals have been recaptured and to investigate population genetic structure and how it changes throughout the growing season.
A wood mouse being released. This is one of two species of mouse found in Scotland,
the other being the house mouse, which is much less common. House mice are greyer
in colour and do not have white fur on their underside, in contrast to the wood mouse.
Often people are surprised to hear that, these days, most mice found in houses are
actually wood mice.
Initial findings have shown that during the early growing season, wood mice made use of both crop and semi-natural habitat. In contrast, voles appeared to make greater use of semi-natural habitat provided via agri-environment schemes. We found evidence that wood mouse population structure is altered around the time when harvesting occurs, perhaps being driven by this disturbance. Research at a larger scale has suggested that arable habitat may be more permeable to wood mice individuals than urban habitat, which tends to be more fragmented.
Amanda hopes her research will provide greater insight into small mammal population structure within agricultural habitat, the most common type of habitat in Britain (70-75% of all land).