Squirrels and People
During medieval times, red squirrels were hunted for their fur which, along with the furs of fox, marten and otter, was used to line cloaks and make warm clothing. Records suggest that skins were actually imported from Flanders to Scotland for this purpose. However, they were also used later in the lady’s fashion industry and, in 1839 alone, over 2,700,000 red squirrel skins were imported to Britain largely to manufacture fur boas (a coil of fur worn around the neck by ladies).
Squirrels can cause significant damage to trees. They do this by stripping the bark to gain access to the sap-bearing tissue beneath. The resulting wounds reduce the value of the timber and make trees more susceptible to disease. Often the bark can be removed right around the main stem (‘ring barking’) and the top of the tree dies as the sap can no longer reach the upper branches. This type of damage can kill trees if it occurs near the base.
Levels of damage are generally related to the thickness and the size, age and species of the tree. Bark-stripping generally occurs between April and July and is more commonly associated with grey squirrels. The exact reasons why squirrels strip bark are unclear. In red squirrels damage tends to occur when there are high densities of squirrels. In grey squirrels, damage levels are also associated with the population density, as well as with the volume and trace nutrient levels of tree sap.
Red squirrel numbers between 1890 and 1910 due to the large scale planting of conifers in Scotland (and elsewhere in Britain) in the late 18th and early 19th centuries (trees between 15 and 40 years old are favoured habitat for red squirrels). In 1903, the Highland Squirrel Club was founded to control red squirrels and over 82,000 animals were killed in the 20 years up until 1933.
Appropriate habitat management is the key to the long-term survival of red squirrels in Scotland. Red squirrels depend heavily on areas dominated by conifers, in contrast to grey squirrels which, to survive, require a high proportion of broadleaved trees. Consequently, habitat management to favour red squirrels should aim for a high proportion of conifers, and should exclude the large-seeded broadleaf specie which favour grey squirrels.
Habitat fragmentation may also make some areas unsuitable for red squirrels, increasing their vulnerability to displacement by the more competitive greys. Grey squirrels can survive in coniferous areas as long as they have access to suitable broadleaf seed supplies, so forest designs which have broadleaf species planted along rides and waterways provide opportunities for grey squirrels to encroach into otherwise inhospitable territory. Large blocks of pure conifers – preferably those exceeding 2,000 hectares – are considered to present the best habitat for red squirrels.
Appropriate forest management is also important to the maintenance of a healthy red squirrel population. Ideally, felling and re-planting programmes should be designated to ensure that a high proportion of trees are always old enough to produce cone crops, which provide a continuous supply of food, and have a closed canopy. Moreover, care should be taken to ensure that, where possible, seed producing areas are left connected by corridors of trees (to enable movement between areas and squirrels.) In areas where red squirrel conservation is a priority, felling should be limited to between October and January when young squirrels are unlikely to be found in dreys.
The red squirrel is included in Scottish Natural Heritage’s Species Action Programme and a variety of research and practical action in underway to conserve red squirrels in Scotland. Red squirrels have also been identified under the UK Biodiversity Action Plan as a species in need of immediate conservation action. A species action plan has been prepared to co-ordinate conservation action in the UK.
Several local groups have been established which enable volunteers to contribute to squirrel conservation. These form a central group – the Scottish Squirrel Group – which helps to co-ordinate action within Scotland. People who wish to get involved should contact their local group, contacts for which can be obtained from SNH. In addition, sightings of squirrels in areas where they are not seen regularly should be passed on to a local record centre, to a local squirrel group or to SNH. Information on areas where red squirrels have been seen regularly in the past have not been noticed recently, are also of importance to the conservation of the species. These records are vital if we are to be able to monitor the changing fortunes of red and grey squirrels and to plan conservation action accordingly.
