Common Hawker

Aeshna juncea

Strange name as it's not that common though is widespread. A large hawker which might be confused with Southern or Migrant Hawker in flight, and unfortunately is not a renowned percher so not easy to pin down, especially as in the main it is also very wary and unapproachable.
In Gateshead the bog pools at Kibblesworth and Burdon Moor hold small populations and I've also seen a female ovipositing at Stargate. 2013 also saw males visiting Thornley Woods Pond and searching for females for the first time (to my knowledge) so will be interesting to see if that is due to the deforestation there and whether it will be repeated.
It can also be seen at Far Pasture and Gibside, or can be encountered along woodland rides. I've even had a few visit the garden, one in particular was hawking a mosquito swarm quite late in the evening.

Common Hawker (male)
Superficially similar to the other male hawkers in our region but large size
combined with full antehumeral stripes should rule out Migrant Hawker,
and thorax stripes and lack of green on the abdomen should
rule out Southern hawker.

From this view the combination of thin antehumeral stripes, yellow costa
(line along front of wing) and blue abdominal spotting
confirm a Common Hawker male. 

Mainly brown with small lemon yellow spots, the female should not be easily
confused with the similarly sized but greenish yellow Southern Hawker
female, though the Migrant Hawker is similar in colour but much
smaller. If perched look for the T shape on segment 2 of the Migrant,
which will also lack the obvious bright yellow costa of the Common.  

The two broad stripes on the thorax are
easily distinguished from the apple green
panels on that of the Southern Hawker.
Males search out females hidden among aquatic vegetation in bogs or pond margins, keeping low over the water when doing so as opposed to flying high when feeding. They will search tirelessly, methodically and thoroughly, and seize any female they find around the neck with their claspers, or quickly jump on a female which has just mated and arrived at the pond to oviposit, and carry the poor girl off again.  
This male actually tried to seize a Southern Hawker female, but as the
claspers don't match the foreign species properly, she soon struggled free.

They form a mating wheel and copulation ensues,
taking about an hour, usually low down in vegetation.

Once copulation is over, the
female is released and she goes
to the pond to oviposit alone.

Eggs spend the first winter unhatched, and the larval stage lasts a further three years, one of the slowest development cycles among dragonflies.

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