In the past, red squirrels occupied the whole of Portugal, and towards the end of the 16th century, they almost died out, probably caused by hunting and increased deforestation due to farming and the naval industry cutting the trees for ship-building. This left the red squirrels being confined to small areas, and by the end of the century there were none left in Portugal. Now they have apparently moved back in from Spain and recolonised forests in the north of the country, and there are reports of them being seen in the north and centre of the county, even sightings almost as far south as the Tagus.
Scotland and Ireland are where the red squirrels now have their main strongholds, but in England, red squirrels only survive on the Isle of Wight and Brownsea Island, where there are no greys; on the Formby coast; and in the pine forests of Northumberland and the Lake District. The red squirrel is officially classed as Near Threatened in England, Wales and Northern Ireland but is locally common in Scotland.
Grey v Red
Although there is no evidence that greys actively hunt and kill the reds, it seems the main cause behind their decline is the introduction of grey squirrels from America, who brought with them a disease, a parapoxvirus, which doesn’t appear to affect their health, but often kills reds. They say that once greys move into an area of reds, sadly the reds will all be dead within 15 years. Greys are also more likely to eat green acorns, which will decimate the food source before the reds can make use of them, and when red squirrels are put under pressure they will not breed as often.
Predators include small mammals such as the pine marten, wildcats and stoats, which prey on nestlings; birds, including owls and buzzards may also take the red squirrel, together with foxes, and even cats and dogs.
Like the greys, red squirrels eat nuts and seeds such as pine nuts and hazelnuts. They will eat fruit where it's available, plus tree shoots, bark, fungi and lichen, but their diet can vary greatly throughout the year. Food can be scarcer during spring and summer, when their diet will then expand to include bulbs, flowers, wild fruits and berries, even insects and occasionally bird eggs.
Squirrels are active all year round and do not hibernate, so in areas where they have settled you might have a chance to see one. They live in a nest known as a ‘drey’, a dense ball made of interwoven twigs (roughly the size of a football), lined inside with moss, leaves, grass and fir.
Dreys are usually located in the fork of a branch tight against the tree trunk, around two-thirds of the way up the tree, and red squirrels will usually have more than one drey, moving their young (known as kits) from one to another if the mother feels threatened or disturbed. Some females produce litters in both April and August, but others produce just one litter annually during one of these periods. After 36-40 days, the female bears her young in her nest, and a typical litter contains 3-5 kits but can vary from 1-8. Sexual maturation of the young occurs the winter following their birth, and they may live 10 years, although 3-5 years is the average.
The babies are ready to leave the nest when they are around 12 weeks old and are sometimes found on the ground. It's not uncommon for baby squirrels to fall out - or be inadvertently pushed out by its siblings. They are not orphans -- they simply need help reuniting with their mothers. Often, mother squirrels will ‘rescue’ them herself by carrying them by the scruff back to the nest.
The notion that red squirrels prefer conifers is somewhat confusing. They are increasingly restricted to large conifer woodlands and plantations due to competition from encroaching grey squirrels. They can exist in conifers better than greys, but red squirrels will reach their highest population densities in mixed or broadleaf woodlands with a diversity of food.
I really liked your article. I would like to report red squirrel sightings to biologists working on this species. Please can you advise who I should contact? Many thanks.
By Rob Baldwin from Lisbon on 30 Apr 2023, 18:27