Original Author: Lorna Hutchison
Lorna Hutchison, Volunteer Project Assistant for Argyll and the Trossachs, tells us about her role in this season’s squirrel monitoring.
My role as a volunteer for SSRS is pretty varied. One of the tasks involves me taking four kilograms of peanuts to Glengoyne and Loch Lubnaig once every two weeks and distributing them amongst eight feeder boxes in two survey tetrads (two by two kilomtere squares). Peanuts make great bait because they attract everything, including squirrels and pine martens, so they’re perfect for squirrel presence/absence surveys like this one. There are around 300 of these tetrads covering potential squirrel habitat all over Scotland and together the results will show where there are no squirrels, where the reds are, where the greys are, and, possibly most importantly, where the red and grey squirrel populations overlap.
The feeder boxes are a little like bird boxes but with a transparent plastic front wall and a hinged, sloping lid instead of a hole to allow the animals in and out. On the underside of the lid is a sticky tab which is there to trap hair from the animals that visit the box. The boxes are cleaned with disinfectant at the beginning and end of the survey period so that transmission of diseases between squirrels is reduced. So every two weeks I go to top up all eight feeder boxes and swap the old sticky tab for a new one until I have three samples for each feeder box. I also remove any leftover peanuts or peanut skins before refilling each box with roughly 500g of peanuts. I then sit with a microscope and analyse the results.
So far, after two of the three visits to collect the sticky tabs, it seems like there are only grey squirrels in the Glengoyne tetrad and only red squirrels in the Loch Lubnaig tetrad. Of course there could be squirrels of the other species present, but not visiting our feeder boxes, so we can’t say for certain that reds are not present at Glengoyne or that greys are not present at Loch Lubnaig. However, that’s why there are four feeder boxes within each tetrad and so many tetrads covering Scotland: together they reduce the uncertainty and build a picture of what’s really going on out there.
Obviously some or all of the tetrads fall on land that is not publicly owned so two days before visiting I call the landowners to give them due warning of my visit. The landowners I deal with are interested in the project, very supportive of our goals, very happy to oblige and have the survey work done on their land. It’s important that this survey work is as simple as possible so that the many volunteers like me and Project Officers are all doing the same thing which allows the results to be compared and analysed. It wasn’t problem-free but the problems I did encounter were pretty minor. For example, a couple of the boxes that were used in previous years were missing (or rather, the tree that it was on had been felled…) so they had to be replaced and new GPS co-ordinates needed taken, the sticky tab stuck to the perspex front of one of the boxes once so I repositioned the tab for the next two week period and I did silly things like leaving the path early so I had to cover more boggy ground than necessary (despite having a GPS!).
The survey period has now finished and the last sticky tabs are being collected and analysed. Soon SSRS will build a picture of the Scottish red and grey squirrel populations of spring 2015 and compare their distributions to previous years. This will help in understanding the impact that conservation measures are having, where grey squirrel control needs stepped up and if the red squirrel population is gaining or losing ground. Finally, as a positive offshoot from the main purpose of squirrel monitoring, the results will also be able to indicate the presence or absence of other endangered species, such as the pine marten.
Should anybody reading this wish to help Save Scotland’s Red Squirrels by volunteering with the project, please check out our volunteer opportunities here: https://scottishsquirrels.org.uk/get-involved/