You may have seen in last month’s magazine, that a red
squirrel was seen bounding along the sea wall at Pett Level. The immediate question that comes to mind is
‘Are you sure?’ Well, at least two
people saw the squirrel, and one even went so far as to describe the white front,
which only the red squirrel has. The
front of a grey squirrel is pale but not as distinctively marked as the red. So assuming that both witnesses saw the same
animal, then it is very unlikely that both mistook a reddish grey squirrel
(which does happen) for a red squirrel, then we have to ask what it was doing
there.
The nearest natural colony of red squirrels is probably on
the Isle of Wight and even though red squirrels can swim, it is unlikely that
they would manage to swim across the Solent, and then take on the 100 miles or
so between there and Pett. One of the
reasons that red squirrels are still living on the Isle of Wight is that the
Solent provides a natural barrier against grey squirrels. There are of course nearer red squirrels in
France, where they are much more common than here in the UK, but again it would
have needed to have travelled here as a stowaway.
The obvious difference between the red and grey squirrels is
in their colouring, but it is by no means clear cut. When red squirrels go through their
pre-winter moult, they temporarily have a grey coat. They also lose the ear tufts that can
normally be used to distinguish reds from greys. Also, continental red squirrels have a much
greyer coat than the UK population. Add
to this the fact that some grey squirrels have a reddish tinge to the fur on
their back and legs. The only reliable
colour difference is in the tail. The
fur of a red squirrel’s tail is always a single colour – grey or red, but the
tail of a grey squirrel has three different shades – a base of reddish brown
surrounded by black hairs with a halo of white ends. Another way of telling greys from reds is
size – red squirrels are quite a bit smaller than grey squirrels, but of course
young greys could easily be the same size as a fully grown red. Despite these confusions there is little
chance of mistaking one for the other in the UK in September if you get a good
look.
Aside from physical differences, there are differences in
their habits. Though both species eat
the same diet of seeds and nuts – and also therefore compete for food, red
squirrels live at much lower densities than greys – about 1 red per hectare
compared to up to 10 greys per hectare.
They manage this largely because greys can digest the tannins in
acorns. Reds will eat a few acorns but
they can’t cope with many. One of the
most interesting wildlife spectacles is to watch grey squirrels burying acorns.
At this time of year they spend hours running back and forth from tree to stash,
and even though they only bury one in each place, research has shown that they
manage to remember where a high proportion of them were buried. The ones they don’t remember or need also
have a fair chance of producing a crop for future generations.
It is interesting to note that though red squirrel numbers
have been declining since the 1880’s when grey squirrels were introduced from
North America, their numbers are currently rising. This is due in a large part to conservation
efforts that reduce grey squirrel populations.
This allows red squirrels to expand into their former territories. Grey squirrels not only out-compete the reds
for food, but they carry a squirrel-pox virus which is deadly to reds, and has
no impact on the greys. There are many
projects in place to protect red squirrels – greys have been eradicated from
Anglesey, are being excluded from the Isle of Wight, and are even being culled
in Cornwall. Perhaps sadly though, it is
not always being done for the best reasons – a population of red squirrels is a
sure guarantee of an increase in tourism!
And I can understand that – I’ve seen red squirrels in Scotland and at
Formby in Lancashire, and they never fail to enchant. I only wish I’d seen the one at Pett Level
and I hope that however it got here; it manages to find a safe place for the
winter.
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