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FOR
INFORMATION AND DISTRIBUTION MAPS FOR CUMBRIAN SPECIES VISIT: www.lakeland
wildlife.co.uk
FURTHER
DRAGONFLY ARTICLES: BEAUTIFUL
DEMOISELLE | DRAGONFLIES
| DOWNY EMERALD
DRAGONFLIES
IN CUMBRIA We
are fortunate in Cumbria to have a lot of good dragonfly habitat, but
our cooler northern climate means that few sites hold more than 10 species.
Damselflies, of which we have six species, are delicate looking
insects with two pairs of almost identical wings. At rest, these are held
closed over the abdomen (except for one species). Dragonflies are
more robust, the forewings are narrower than the hind wings and these
are held open when the insect is at rest. DAMSELFLIES First
to emerge in the spring is usually the Large
Red Damselfly followed by the two easily confused "blues".
The male Azure Damselfly has narrow
blue stripes on the thorax and a characteristic black U shape
on the second segment of the abdomen, whilst the Common
Blue has broader stripes and a club shaped mark on this
segment. The similar Variable Damselfly
has two small populations on the West Coast; it is difficult to
identify, but males have the U-shaped black mark on segment two
joined to the black ring below it, creating the impression of
a wine glass!
The
Blue-tailed Damselfly is more easily recognised by its mainly
black abdomen with prominent blue band near the tail. Females
are interesting in that the colouring of the thorax varies (see
above for a reddish form).
DRAGONFLIES
HAWKER
DRAGONFLIES. Sitting
by water on a warm summer day as a large hawker dragonfly glides past,
it is hard to imagine that such large insects have been around for over
300 million years. Their large size, beautiful colours and spectacular
acrobatic skills remind us that they are essentially insects of the tropics.
The few hardy species able to survive in Britain need to be nurtured and
cherished. These large dragonflies, with restless patrolling flight, have
their peak flight period in August. Until the last ten years the only
hawker of the region was the Common Hawker, but now three more species
may be seen.
The
Lake District is ideal habitat for the Common Hawker,
which is found around bog pools at upto 600 metres in the north and west
of Britain; it has a preference for slightly acidic moorland and Grizedale
Forest and the mosses of Torver, Subberthwaite and Outley are good strongholds.
Look out for the adults in late July and August; males appear quite blue
and with binoculars the yellow leading edge (costa) of the wings can easily
be seen. Females (brown with yellow markings) are more likely to be heard
rustling noisily in the vegetation as they seek out suitable sites to
lay their eggs. Eggs are laid on living plant stems close to the surface;
larvae may take upto four years to develop into adults in these cold environments.
Males
patrol small bays along the pond edges usually close to trees. Occasionally
they may dart out over open water to catch an insect. This is a very inquisitive
species which, unlike the Common Hawker, will approach close to humans.
Hold a stick out in front of you and it will hover near the end, jumping
from side to side as if to weigh up the situation. Again females are probably
first noticed as they rustle in the vegetation.
The
Brown Hawker is a sturdy
dragonfly that creates a beautiful orange-brown reflection from its wings
when flying in sunlight. In the early 1990's it colonised the Furness
peninsula, liking the many pools left by gravel and iron ore extraction,
being tolerant of more polluted waters. Almost every pond from North Walney
through Dalton and Lindal to Ulverston carries the species by late August.
With binoculars the sky-blue markings on the abdomen of the males can
be seen clearly. Females generally appear lighter in colour in flight,
and have a broader abdomen with yellow markings. Males are often seen
hawking a long section of hedgerow, resting only to eat an insect. They
also fly high and purposefully above the tree tops. Where they occupy
the same sites as the Southern Hawker they are easily chased off by the
less robust species. Females oviposit alone, preferring dead and softened
wood just below the water surface, near the edge of the pool.
A
species to look out for in South Lakeland and around Carlisle
is
the Emperor
Dragonfly - hopefully it will be
seen more frequently in coming years. There have been occasional
sightings of this resplendent species since 1995 and an egg-laying
female was seen near Windermere in 1999. With green eyes, apple-green
thorax and sky-blue abdomen it does indeed look regal. It is an
earlier species than the others and may be on the wing from June
to August.
Finally,
a fourth species, the Migrant
Hawker, is now turning up on a regular
basis in Cumbria. Slightly smaller than the Common Hawker which
it closely resembles. Immatures have a lilac/grey colouration
but the key identification is the yellow triangle at the base
of the abdomen. Specimens seen in early August may be locally
bred, otherwise, as its name implies, it is a species that can
arrive by migration later in the month or in September.
EMERALD
DRAGONFLIES. Cumbria
has only one member of this family, the Downy
Emerald. We are fortunate to retain
colonies of this compact dark greenish bronze species, with apple
green eyes, in the Coniston/Ambleside area, for example at the
beautiful locations of Loughrigg Tarn and Yew Tree tarn. Emergence
starts from mid-May onwards (see DOWNY
EMERALD for more details). A trip to northern Scotland or
Sussex would be necessary to see it otherwise.
However,
in 2004 the Broad-bodied Chaser
moved over the border from Lancashire and was seen at Foulshaw
Moss. This is another species new to the county well worth looking
out for, even around garden ponds.
DARTERS.
Of the four darters possibly encountered in the area two
are common, one is nationally rare and one is a recent migrant
just gaining a foothold. The attractive
White-faced Darter hangs
on tenuously to the west of Windermere and at Scaleby Moss near
Carlisle. Strenuous efforts are now being made to provide improved
habitat for this species. Its only real stronghold is in the far
north of Scotland. In contrast the red Common
Darter turns up everywhere from July
to September as numbers can be swollen by influxes of migrants
from the continent, although the less frequently seen females
are yellow
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