Squirrelly Scotland 🐿

On a wet and rainy day at home, it seems like a great time to tell you about red squirrels! Who doesn't love their cheeky little faces, fluffy tails and tufty ears?

Oh my gosh, PEANUTS!!!

I visited Western Scotland with my family and our 2 dogs at the end of August 2020, and amidst all the panic of COVID-19 and desperately trying to finish my Masters thesis, I must say it was wonderful to get away. On arrival, we discovered that our rented log cabin we had booked for the week was surrounded by pine woods in which dwelt a whole host of wildlife including red deer, herons, and the forest's little ginger-ninjas. I don't call them that lightly either - their ninja skills at apparently teleporting from tree to another were incredible to witness, and extremely difficult to photograph! I did manage some pictures that I was pleased with, but all of them on a peanut feeder set up beside one of the cabins.

So what do we need to know about red squirrels, Sciurus vulgaris? Well the good news is that contrary to what many Brits believe, red squirrels are NOT actually currently threatened with extinction, as they cover enormous areas of Europe and Asia and are listed as Least Concern on the IUCN Red List of Endangered Species (www.iucnredlist.org/species/20025/115155900). The bad news is that their population is still decreasing overall, and yes in the UK they are definitely not doing so well... The main culprit? Sadly it is indeed the cute (but less so than the reds!) grey squirrels (Sciurus carolinensis) that most of us see in our gardens. Grey squirrels are native to North America, but have become highly invasive in the UK. Worse, they have now reached continental Europe, and their spread is likely to be exponential. They threaten the red squirrels in two ways. Being larger, grey squirrels outcompete the reds for resources, pushing them out of high quality habitats. They also carry disease. The parapox (or squirrel pox) virus is carried asymptomatically by grey squirrels, but it is often deadly to the red squirrels. Think of it like COVID-19: people under 20 are like the grey squirrels (somewhat susceptible, but most will get it only asymptomatically and the few that do show symptoms generally have a high chance of recovery), while people in their 70s and above are the red squirrels (much more likely to get severe symptoms, and with a much lower recovery chance, but still no guaranteed outcome). The virus is passed predominantly when the species are close together, but can also move within species so reds can also infect other reds. The virus induces lesions on the skin of the squirrels, particularly on the face and limbs. On holiday with us was my sister's partner, a veterinary pathologist currently working on a study of red squirrels and parapox. I learned so much from him about these wonderful creatures, and the virus threatening them.

A red squirrel with lesions induced by squirrel pox virus.

So what can we do to try and protect Scotland's little Ginger Ninjas? Well first of all we can stop chopping down their forests, and make sure to connect forest areas split by roads with squirrel bridges to allow the squirrels to cross. Habitat fragmentation is fractioning the population into many small groups, which become inbred and have much lower access to the resources they need. Second, we can put money into the research and development of a squirrel pox vaccine, to try and generate immunity in populations of red squirrels. And finally, we can work to increase populations of pine martens.

Hold up.... Pine Martens?! Aren't they predators of the red squirrel?! Yes they are - funny how nature works eh? The natural food source of the pine marten (Martes martes) is indeed red squirrels, but there's one disadvantage of being bigger when you're a grey squirrel - you're fatter and slower, so definitely a favourite of the pine marten! Increased pine marten populations can really help to reduce the number of grey squirrels running around, so promote red squirrel survival. Further, as their name suggests, pine martens also prefer pine woodland, much like the red squirrels, whereas the greys tend to prefer more deciduous, mixed woodland. While this may mean that within these forests the red squirrels again become the martens' preferred mealtime treat, promoting pine forest growth and protection for the sake of pine martens also provides much more habitat for these adorable little squirrels.