The male Broad Bodied Chasers have got all dressed up for the
summer. It takes a week or so from when
they first emerge as glittering, golden bundles of energy to acquire this fine
blue. Slowly the males' abdomens darken then a haze of sky blue, called
prunesence, coats their tails. The younger males look much like females except they
have slightly narrower abdomens. They keep out of the way of the mature males in their
blue war paint, hanging around hedgerows and paths rather than risk conflict
with their older kin. This nervousness changes once their blue fighting and mating
colours have developed . Then it is time to head to a pond and challenge for a
territory. These Chasers fly fast, often low but with erratic zig-zags, back
and forth across ponds, even small, garden sites. They do not mind nearly dug
out pools and are happy in cities. Every few minutes the territorial males
perch on obvious branches and stems, and you can get close (the photo above was taken with an ordinary digital camera, not a telephoto). They are much more
concerned about air-borne rivals than sneaky humans.
Adult Broad Bodied Chasers are good colonists and can turn
up almost anywhere. They may not have bred from the ponds across which they
now patrol and fight. The best evidence for breeding is finding their larvae,
called nymphs, or the cast skins left behind as adult emerge. These skins are called
exuviae. They are as gnarly and peculiar to look at as the adults are glamorous
and racey. Here is one, the exuviae looking like some parchment mould from
which the adult has been cast. The wispy white strands are where the cast skin
ran inside the length of the breathing tubes, (trachea), that ramified into the
body of the larva to carry oxygen. When the adult emerges and pulls itself free
of the old skin these are pulled inside out a bit like when you take off a
jumper or coats and the sleeve gets pulled inside out. The dragonfly season is
hitting its stride. Northumberland remains a poorly recorded county for dragon
and damselfies, even areas such as Druridge Bay that attract good numbers of
bird watchers and outdoor enthusiasts. Northumberland is a region into which
new species have expended from further south, and the east coast of England is the
likely first land fall for occasional vagrants from the continent, just as with
rare birds. The western hills and bogs are even less recorded. Well worth watching out, you are very likely to find something new.
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