Summer 1999
ARE GREY SQUIRRELS INVADING THE SEFTON COAST ?Article by Sarah Bentley, NPI Red Alert North West Project Officer
The Sefton Coast has long been a stronghold for the red squirrel and has always been considered a grey squirrel-free zone. Over the last six months, however, NPI Red Alert North West has received increasing numbers of reports of grey squirrels. They are certainly becoming established in Southport and from here it is a simple step to reach the coastal woodlands. Odd sightings of grey squirrels have been reported on the coast from time to time in the past; so should we be getting ready for action or is this another false alarm? A pattern has emerged in Cumbria where grey squirrels are progressing further north each year. Grey squirrels are occasionally reported and then never seen again in red only areas for as long as five to ten years before the main population advances. These 'scouts' seem to be dispersing animals which range over wide areas, crossing seemingly inhospitable habitats on their travels, but eventually followed by the main front of the grey squirrel advance. With greys becoming much more numerous in Southport and a few sightings reported in Formby, Hightown and Crosby, perhaps now is the time for us to prepare for action.
Why are grey squirrels a threat to reds ?
Grey squirrels were introduced to Britain from North America in the late 19th Century. As they have spread through England, Wales and parts of Scotland so the red squirrel has declined. This pattern was observed as early as the 1930s and it was assumed that the larger grey squirrel aggressively drove the reds out and even killed their young. However, observations of red and grey squirrels do not support this theory and a considerable amount of research has been carried out to investigate what really happens. Red squirrels are adapted to live in coniferous woodlands. This explains their very light build - an adaptation for getting to the ends of the conifer branches to reach the cones. Without a competitor, red squirrels can also survive in broad-leaved woodland, but the grey squirrel is much more successful in this habitat. It spends more time on the ground feeding on the fallen seeds, is able to put on twice as much weight in the Autumn as the red and digests acorns much more efficiently. This means that when conditions are harsh the grey squirrel is more likely to survive and has a better chance of successful breeding than the red. Grey squirrels therefore gradually replace reds and this happens most quickly in broad-leaved woodland. A further threat posed by the grey squirrels is the possibility that it may carry a virus which can be transmitted to the red squirrels, but further research is needed to confirm this.
How can you tell a grey squirrel from a red ?
Colour is the most obvious difference but it cannot be relied upon; red squirrels sometimes look grey and grey squirrels can look red. In winter look for ear tufts on the red squirrel (they lose them in the summer) and look at the tail of the squirrel. The grey squirrel has a distinctive halo of white tipped hairs around the edge of the tail, while the red squirrel tail is more uniform in colour. The grey squirrel is also slightly larger and much stockier than the red.
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