On the 9th of February I spent a very interesting day with one of my colleagues, Becky Priestley, as she carried out the next phase of our newest project for the restoration of the Caledonian Forest. Becky is our Wildlife Officer and she’s working on a three year project, funded by the Heritage Lottery Fund (HLF), the People’s Trust for Endangered Species and an appeal to our supporters, for the translocation of red squirrels (Sciurus vulgaris) to suitable native forests in the northwest Highlands that are currently missing these arboreal, bushy-tailed mammals.
The project began last year and Becky carried out two successful translocations to sites in the northwest – the first to a native pinewood remnant at Shieldaig, and the second to another pinewood area at Coulin. Local people welcomed their new wildlife neighbours and have been involved in monitoring the translocated squirrels. Thus, we know that they have bred successfully, and have also moved around, expanding their range into the habitat available for them, with one of the squirrels released at Shieldaig having been seen about 14 km. away some months later. We’re still seeking additional funds for this project, so if you’d like to support it, donations can be made here.
This year, the aim is to carry out 3 translocations – two in the early part of the year, in February and March, and the other one in the autumn. (It’s not possible to do them in the intervening months, because of the risk of disrupting the squirrels’ breeding seasons.) Becky began the first of these translocations on the 3rd of February, moving 4 squirrels from near Culloden to native woodland sites at Plockton, near Kyle of Lochalsh on the West Coast. Her plan is to move 30 reds there altogether, so on Wednesday 9th February I joined her for the second day of this translocation.
The preparations for the translocation had begun about 4 weeks previously when Becky installed squirrel feeders – perspex-fronted boxes with flip-up lids – on trees in areas of Scots pines (Pinus sylvestris) at a number of different sites near Culloden and Croy, to the east of Inverness, on the Black Isle to the north, and down the east side of Loch Ness. These were filled with peanuts to attract squirrels, and were topped up regularly, either by Becky or some of the local volunteers who help her.
Becky had selected the sites by surveying the native woodlands in the area and choosing the locations where there were clear signs of red squirrels feeding – pine cones that had been stripped in a distinctive way, when the squirrels extract the seeds they contain. The translocations are carried out under a licence issued by Scottish Natural Heritage (SNH), and one of their conditions is that no more than two squirrels can be moved from an area of 200 hectares in one year, to avoid depleting the donor populations. Thus, Becky had to find sites with good numbers of squirrels (as evidenced by the stripped pine cones) over quite a large area to provide the 30 animals she was planning to move to Plockton. About three weeks after the feeders had been put out at each site, Becky installed the traps, which are wire cages with peanuts inside them (again to attract the squirrels) next to the feeders themselves. The traps are out for three days with peanuts in them, without actually being set to be triggered, so that the squirrels can get accustomed to them as a place to obtain food.
On the morning of the 9th February, beginning at 7 am, Becky went round the eight traps she was planning to use that day and set them so that they would be triggered when a squirrel went in to them. The trigger mechanism is a simple pressure plate in the base of the trap – when a squirrel steps on it to reach the peanuts beyond, it releases the gate of the trap, which closes behind the squirrel, trapping it inside, without harming it in any way. Becky and I had arranged to meet at 8.45 am, after she’d set all the traps, and the plan was to make three circuits of the eight traps during the morning, hoping that they would catch a few squirrels in that time.
As we set off on the round of checks, Becky was optimistic that we’d soon find a squirrel in one of them, but the first three traps turned out to be empty, which was rather discouraging. When we reached the fourth one, Becky saw there was something in it through her binoculars, but as we approached we discovered it was a jay (Garrulus glandarius), not a red squirrel, that was inside. With their keen eyesight, jays can spot food such as peanuts from quite a distance, and she’d found one in a trap the previous week as well.
This was particularly disappointing, as this trap was one where there had been signs of squirrels using the feeder, and Becky had been optimistic it would catch a squirrel. Instead, she had to release the jay, and reset the trap, hoping that it would attract a squirrel later on in the morning.
While we were checking the traps near Culloden, Becky’s assistant, Matt Dalby (who is also one of the leaders of our Conservation Week groups), was checking the traps down the east side of Loch Ness, between Foyers and Inverfarigaig.
As we moved on from the trap that had caught the jay, Becky received a text message from Matt, letting us know that he had got two squirrels in his traps during his first round, and this news lifted our spirits. However, this was offset almost immediately at the next trap we visited, as it too had been triggered by a jay, and Becky had to reset it after releasing the bird. Driving on from there, we reached the end of the circuit of traps, and, rather disappointingly, came away from all of them empty-handed.
As we set off to to begin the second round of checks, I suggested that because two of the traps had caught jays it was perhaps a sign that we would find some squirrels as well. Then we got another text from Matt to say that he had caught another two, bringing his total to four squirrels – more good news! However, for us, the first two traps we checked were once again empty, but then at the third one our luck changed. When we stopped the car, Becky could see straightaway that there was a squirrel in the trap.
Knowing that I wanted to get some good photographs of any squirrels we caught, Becky suggested I take some images from a distance, because the squirrel would become more agitated and active when we approached it closely. Putting my longest telephoto lens on my camera, I was able get some images of the squirrel feeding on the peanuts in the cage and I gradually crept closer, staying behind some nearby trees as I did so, in order to minimise my visibility from the trap. This was quite successful, and it was encouraging to see that the squirrel was not too alarmed.
For two or three minutes I moved slowly closer, allowing time for the squirrel to get used to my presence. Then at a certain point I moved from behind the vegetation for a few quick close-up shots, before Becky took the trap down from the tree.
At first the squirrel seemed almost curious as it looked at us, but after a couple of minutes it began moving around quickly, trying to find a way out of the trap.
It was time for Becky to take the trap down from the tree, so she approached it carefully (and with a grin on her face, as it was a beautiful squirrel that looked in very fine condition). She quickly cut the cords that were holding the trap to the tree, and gently lowered it to the ground. I was able to get a few photos during this process, particularly once the trap was on the forest floor, at the base of the tree. The squirrel of course was still trying to find a way to escape …
It’s important to minimise the time that the squirrel is agitated, so straightaway Becky covered the trap with an old towel. In the darker conditions, the squirrel settled down and became still almost immediately.
She then transferred the trap, with the towel over it, into the back of the car. Closing the tailgate gently, we got in and drove on to check the next trap in the circuit. Becky recommended we be quiet as we travelled, so that our voices didn’t disturb the squirrel unnecessarily. When we reached the next trap, we were delighted to find there was a squirrel in it as well – it felt as though our luck had really changed. Together with the four that Matt had caught in the traps he was checking, this gave us six altogether, in addition to the four she had caught and translocated the previous week.
This project of translocating red squirrels was first developed by Roy Dennis, who is a patron of Trees for Life, and who was a member of our board for many years. His charity, the Highland Foundation for Wildlife, carried out a successful translocation of squirrels to Dundonnell in the northwest Highlands in 2008-09. 44 squirrels were moved there from Moray and Strathspey, and recent monitoring has shown they have increased in numbers and expanded their range to fill up all the habitat available for them there.
Our project now is using the techniques that Roy developed, and we’re working in partnership with him on it, for example with the applications to SNH for the licence required to move the squirrels. The purpose of the project is to re-populate suitable native forests in the northwest Highlands with red squirrels, both to return this species to woodlands where it would have existed in the past, and to create additional populations of red squirrels that are a long way from the introduced non-native grey squirrels (Sciurus carolinensis).
The grey squirrel has displaced the red squirrel from most of England, largely through out-competing it for food. However, the greys also carry the squirrelpox virus, which is harmless to them, but usually fatal to the reds. Considerable effort is being made now to prevent the greys from spreading further north in Scotland from the Central Belt, where they are well-established, to protect the reds in the Highlands, which is the stronghold for the species in the UK. Our project complements that work, by establishing additional populations of reds in native forests in the northwest Highlands, which have been lacking squirrels for decades or even centuries. Because those forests are isolated from other woodlands by large areas of tree-less ground (due to past deforestation), the red squirrels are unable to recolonise them by themselves – they will not cross large areas on the ground, because they would be vulnerable to predators. Red squirrels also provide an important ecological function in our native woodlands by helping with seed dispersal. They collect and cache the seeds of Scots pine, acorns from oak trees (Quercus petraea) and the nuts of hazels (Corylus avellana). They never find all the seeds they stash away, and those they overlook go on to germinate, thereby enabling a new generation of trees to grow. When squirrels are missing from a woodland, this function is also absent, and that is one of the factors that has led to a lack of regeneration in many of Scotland’s forests in the past couple of centuries.
After getting the second squirrel into the car, we continued our round of checks, but there were no more squirrels in any of the other traps. We made a final round, in which Becky de-activated the traps, and then we headed over to the Black Isle, just north of Inverness, where we had arranged to rendezvous with Matt. In a quiet, secluded location that Becky had scouted out before, the squirrels would be checked for their health and then transferred to special nest boxes, ready for the journey to the release site near Plockton.
When we met Matt, the first job was to prepare the nest boxes, which are lined with straw and provisioned with some peanuts and a slice of apple (to keep the squirrels hydrated during the journey).
Once all the materials were inside each nest box, the tops were screwed down, ready for the squirrels to be moved in to them. Then, one by one, each squirrel was carried in its trap, still covered by a towel to keep it calm, to where the nest boxes had been laid out, ready for the transfer process.
Under the terms of the licence from SNH, Becky has to carry out a health check on each squirrel before it is translocated, so this means that the transfer of each squirrel from a trap to a nest box is a three stage process. The first step is to get the squirrel out of the trap, and this is done by holding a large white sack over the end of the trap, and then opening the trap door. Sometimes the trap needs to be darkened by covering it with the towel, to encourage the squirrel to move into the sack, which is brighter.
Once a squirrel is in the white sack, the open end of the sack is held against a small cylindrical metal inspection cage, and the sack is rolled up from the closed end, so that the squirrel moves towards the cage. As squirrels are very active, and have sharp teeth and claws, they need to be immobile for the health checks to be carried out, and the inspection cage serves this purpose. The combination of rolling the sack up and the daylight at the end of the inspection cage makes sure that the squirrel goes in all right.
It’s obviously not very comfortable for the squirrel to be so closely confined, so this part of the process is carried out as swiftly as possible, to minimise the time each squirrel is in the cage. This is usually two or three minutes at most. The health inspection itself consists of two parts. The first of these is a visual inspection to identify the sex of the squirrel, to look for any external parasites such as fleas or ticks (Ixodes ricinus), as well as any physical abnormalities or signs of injury or disease. It’s important to make sure we don’t translocate any animals that aren’t completely healthy or fit.
Once the visual check is complete, the second stage of the process is to take some measurements of each squirrel – its weight, and the length of its tail.
Becky uses a simple weighing scale, which the inspection cage is suspended from, and the total weight is noted down. The actual weight of the squirrel itself is calculated by subtracting the known weight of the empty cage from this figure.
After that, a tape measure is used to determine the length of the squirrel’s tail, in the final part of the health check process.
When our project began last year, SNH required that each squirrel was examined by a vet before it was translocated. However, this proved to be very time-consuming, as all the squirrels had to be taken to a vet, and it also necessitated sedating the animals. This considerably lengthened the time the squirrels were captive, and provided little additional knowledge beyond what Becky obtains from her health checks, so she was very pleased this year when SNH relaxed that requirement, as it makes the entire translocation process quicker and less traumatic for the squirrels.
Once the health check is complete, it’s time for the squirrel to go into the nest box, ready for the journey to the release site. The hole in each nest box has been cut to match the diameter of the inspection cage, which has a sliding end to it. Becky carefully positioned the cage against the hole in the nest box, and Matt gently slid the end of the cage off. Then it was a question of coaxing the squirrel to move out of the cage and into the box itself.
We had to do this process for each of the six squirrels we’d caught, and in some cases the squirrels went very easily and quickly from the inspection cage into the nest box. However, others were more reluctant to move, and Becky had to cover the inspection cage with the towel, to encourage the squirrel to leave the cage and go into the box. Once the squirrels were in the darkness under the towel, it seemed to make it easier for them to make the move, and overall it was quite a graceful process, which didn’t seem to stress the squirrels unduly.
Once each squirrel was in its respective nest box, Matt sealed the entrance hole with masking tape, to ensure that the squirrels couldn’t make an accidental exit during the journey to the release site at Plockton. The tape also means that the interior of the nest box is quite dark, which helps to keep the squirrel calm and quiet. Several smaller holes drilled in the box allow for the passage of fresh air, and the squirrel has the peanuts and the slice of apple to eat during the two hours or so that it will be in transit.
With all six squirrels transferred to the nest boxes, we said goodbye to Matt, whose work for the day was done, and Becky and I set off on the journey to Plockton, where the squirrels would be released. Becky was very pleased as the six squirrels had turned out to be three males and three females, making them an ideal founder population that can breed and multiply in their new woodland home. It was 3 pm when we left the Black Isle, and with a journey time of almost two hours, we were concerned about reaching our destination in daylight, so that the nest boxes could be put up at the release site before darkness fell.
When we arrived at Plockton, we were met by Gavin Skipper, who works as a ranger at the National Trust for Scotland’s (NTS’s) Balmacara Estate, where some of the squirrels would be released. Gavin is very enthusiastic and supportive of the project, and is being assisted by local volunteers who were enlisted as a result of a public talk Becky gave in Plockton. They are equally keen about the arrival of squirrels in the woods there, and they’ve been helping to provide food for the four squirrels that Becky had released the previous week.
Gavin helped us carry the nest boxes to the area that Becky had previously scouted out as a good release site. Once there, it was a relatively quick process to affix each nest box to a tree, using screws at the top and bottom of the back of the box. Becky had decided to put out the squirrels in pairs, with two boxes installed on trees about five metres apart from each other. In addition to the two nest boxes at each site, a squirrel feeder is also put up, so that the squirrels have immediate access to food in their new home. Each nest box is oriented so that when the squirrel emerges from the hole, it is looking straight at the feeder.
This is important because when each squirrel emerges from its nest box, it will be in a totally unfamiliar location, and it won’t know where to find food until it has explored the area. We put up the three pairs of nest boxes in different areas of forest around Plockton. One group was put out on NTS land, the second on private land that is managed by a commercial forestry company, and the third pair went to a nearby 20 acre area of privately-owned woodland, where the owner was very welcoming and excited to be hosting the squirrels.
By the time we finished installing the third pair of nest boxes, it was completely dark, and we were using torches to see what we were doing. It had been a very long day, particularly for Becky, who had started setting the traps in the woodland near Culloden at 7 am – it was now after 6.15 pm. Once each nest box was affixed to its tree, the final act was to remove the masking tape that had been covering up the hole during the journey.
This enables the squirrel to come out in its own time, but Becky found from the translocations last year that the squirrels always stayed in the boxes overnight, and left the following morning. This was revealed by positioning camera traps facing the holes in the nest boxes, and in every case it was in the morning when the squirrels ventured outside. Once the masking tape is off, Becky places some moss loosely in the hole. This provides some sense of enclosure for the squirrel inside, but is easy enough for it to push past in the morning.
With the day’s work finally over, Becky and I went our separate ways – I was returning home for the night (with a journey of two and a half hours ahead of me), while Becky had arranged to stay locally. This was just as well as she’d been at work for almost 12 hours by this time. In the morning she would go around the nest boxes to make sure that all the squirrels had got out all right, and would take down the nest boxes from the releases that she’d done the previous week. In the coming days, she and/or Matt would return to the sites where the traps had been put out, near Culloden and on the east side of Loch Ness, to take down the remaining (and de-activated) traps that hadn’t caught any squirrels and the feeders, as they were no longer required. In the following week, she would repeat this whole process on the Black Isle, where feeders had been in place for several weeks and the traps would be installed there, to hopefully catch another batch of squirrels that would join those already translocated to Plockton.
For me, it was a very satisfying experience overall, and I couldn’t help but be impressed by Becky’s tremendous enthusiasm for the project, and all the commitment and hard work she demonstrated during the day. She gives a lot of care and attention to the squirrels, making sure that they have the best possible start in their new woodland homes, and it’s very inspiring to be part of this important work to return these charismatic arboreal mammals to forests where they have been missing for a long time.