Damselflies in distress forced back to UK by climate change
By Michael McCarthy, Environment Editor
Thursday, 22 July 2010
The Dainty Damsefly has returned to Britain
Damselflies don't sound like they'd do anything as dramatic as invading
anywhere, and the dainty damselfly sounds like it would do so least of all.
But that's what's happening in southern England, as several species of
these delicate, smaller relatives of the dragonflies cross over from the
continent and start establishing populations here.
The dainty damselfly, a flying matchstick of bright blue and black, is the
latest of a number of new arrivals from Europe which are thought to have
been brought to Britain by rising temperatures caused by climate change.
It is actually a returner, rather than a completely new species, as it bred
in at least one site in Essex until the population was wiped out in the
great floods of the winter of 1953. There was no further sighting for 57
years until four adults were observed and photographed recently in north
Kent by two recorders for the British Dragonfly Society, Gill and John
Brooks.
On the Continent, Coenagrion scitulum has a predominantly central and
southern distribution, although there have been signs of a northerly
expansion of its range. In the last fifteen years the dainty damselfly has
recolonised Belgium after a long absence, and appeared for the first time
ever in The Netherlands; it also appeared on Jersey in 2009.
Its appearance in Britain is significant as it follows the establishment of
other unusual damselflies in southern England over the last decade or so.
The small red-eyed damselfly, now a common breeding species in much of
south-east England, first appeared in Britain only as recently as 1999,
while the willow emerald damselfly appeared in 2007 and may now be
established in Suffolk.
The British Dragonfly Society comments that "these events, which for
Britain's dragonfly fauna are pretty much unprecedented, are thought likely
to be a consequence of ongoing climate change, and many species with a
primarily Mediterranean distribution in Europe are indeed known to now be
advancing northwards."
In fact, the march of the damselflies is only one aspect of a much wider,
continuing invasion of southern Britain, possibly caused by the warming
climate, by a range of continental creatures which can fly - both insects
and birds. Insects in particular are flooding in, and over the past decade
a whole series of continental bees, wasps, moths, butterflies, dragonflies
and grasshoppers has appeared here
At least one new continental dragonfly species, the lesser emperor, is now
seen in Britain every year and is thought to have established a population
at Dungeness, while others, such as the brilliantly-coloured scarlet
darter, are waiting in the wings and could cross the Channel and start
breeding here very soon.
This happened last year with an attractive continental butterfly species,
the Queen of Spain fritillary, which crossed over from Normandy to Sussex -
thought to be only about a six-hour flight for a butterfly - and set up a
breeding population near Chichester. Other continental butterfly migrants
such as the clouded yellow and the red admiral are now managing to survive
over winter, while we are increasingly seeing the charming hummingbird
hawk-moth, which does indeed look just like a hummingbird as it moves in
and out of flowers, seeking nectar.
European bees and wasps are also arriving. Perhaps the most dramatic
arrival is the large, deep-blue, alarming-looking but harmless, violet
carpenter bee, Europe's biggest, which began breeding in a dead Bramley
apple tree in a garden near Leicester three years ago. A rather less scary
arrival is a bumblebee, the brown-banded carder bee, which has now begun
breeding on brownfield sites in the Thames estuary.
Several continental bees and wasps now in the UK are so unfamiliar that
they do not even have English names, such as the large social wasp
Dolichovespula media, which created concern among gardeners when it arrived
in the UK in about 2000 because of its size. Other wasps that have recently
come into the country include the bee-wolf, which hunts bees for food, and
the French spider-eating wasp Episyron gallicum.
But it's not just insects crossing the channel to join us. A number of bird
species have moved in, including the little egret in 1996 and the cattle
egret in 2008, while this year, the purple heron bred successfully in
Britain for the first time. Other species that may well establish
themselves include the great reed warbler, the black kite, the black-winged
stilt and the serin.
--
http://www.dragonflysoc.org.
Coenagrion scitulum - Dainty Damselfly
Description
Length: 32mm
Both sexes appear yellowish when viewed from the underside. The pale brown
pterostigma is longer than in other Coenagrion species.
In the male, S2 has a "wine-goblet" shaped mark, occasionally reduced to a
bar or crescent. S8 is blue but S9 has black markings towards the rear. S6
and S7 are entirely black.
The female is blue with black "rocket-shaped" markings on the abdomen.
Habitat
Open but well-vegetated waters. It can tolerate some salinity.
Status and Distribution
Extinct in Britain since 1953 when its known breeding sites in Essex were
destroyed during the catastrophic flooding.
--
http://www.arkive.org/brown-
Brown-banded carder bee (Bombus humilis)
Description
The brown-banded carder bee B. humilis is one of the 24 species of
bumblebee or cuckoo bee found in the UK. It is also one of the most
endangered. This tawny coloured species has a characteristic brown band on
the upper surface of the abdomen, hence the common name.
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