13th February, 2009
The increasingly loathed 'tree rat' may not be to blame for the red squirrel's decline after all
The birds of sea and farmland have had a decent share of the headlines recently: their falling populations have become increasingly recognised as indicators of unsustainable human practices. But it’s not all doom and gloom: the numbers of some species have actually been seen to improve. Very good. But now there are some new kids on the block. Or, to put it more accurately, the chopping block. The British Trust for Ornithology has announced that several woodland species of bird are rapidly disappearing. In some cases populations have dropped by up to 80 per cent. Several reasons are being put forward for why this could be.
Some of them are straightforward, such as reduced lowland woodland management or increased urbanisation to the woodland edge. Others are more complicated: hunting pressures on migratory species, or climatic change causing chicks to hatch out of sync with the emergence of insect foodstuffs. But tucked away in the list is an intriguing suggestion that certainly wouldn’t have been made a few years ago: the grey squirrel might be to blame. This theory is the latest stage in the demonisation of a creature that is being moved unerringly towards top pest status.
The grey squirrel, I predict, will soon become one of the leading natural scapegoats for ecological change in Britain. Bit by bit, opinion is being turned against the creature, its recent addition to British fauna damning it as an unfavourable species that shouldn’t be here at all. Blamed for digging holes in lawns, uprooting bulbs, bark-stripping, scaring off birds from nut-feeders, aggressive behaviour, and now the decline of our woodland songsters, the increasingly loathed ‘tree rat’ is being turned into mammalian enemy number one.
It seems strange that an animal that has been here longer than anyone alive on these islands can remember (it was ﬁrst introduced in the 1870s), and which spread fairly rapidly and was already well established by the 1930s, should only now be becoming a hate ﬁgure. Of course, the main reason for this bile is the oft-quoted dislodging by the American invader of the pretty little native red squirrel. How typical of the Yanks. Overfed, over-rated and over here.
But is the grey squirrel really to blame for the red’s decline? Back in the US, it shares land with four other squirrel species, one of which is very similar to our own red squirrel, and they all manage to get along together just ﬁne. In Britain, the two species have rarely been seen ﬁghting together, while they often have been seen feeding near each other. In some parts of Britain, it took up to 20 years for the red to disappear from areas into which the grey had moved. Perhaps other changes are responsible for the red’s disappearance, changes that the larger grey, with its wider diet and greater inclination to come to the ground for fallen food, is better equipped to survive.
Perhaps it’s the weakness of the red that should be looked at, rather than the strength of the grey. It’s little realised by the public that this is not the ﬁrst time that the native version has struggled. In fact, there’s a strong likelihood that not one single Scottish red squirrel could trace its family tree back for more than about 230 years in this country. The woodland clearances of the 18th century made the animal effectively extinct in Scotland, a fate from which it was saved only by reintroductions from Scandinavia. By the mid-19th century, the red squirrel was absent from much of its current Scottish habitat, and its reintroduction in many areas preceded the appearance of the grey in England by only about 20 to 30 years.
So perhaps changes in Britain’s woodland content and management, changes that date back 200 years, mean that the red squirrel is no longer suited to this country. And maybe the same and more complicated reasons could be responsible for the decline of our woodland birds. It’s just that it’s so much easier to lay the blame for our ecological tampering at the door of the dreaded American invader.
This article first appeared in the Ecologist April 2005
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