Azure Damselfly

Coenagrion puella

The Azure Damselfly is a widespread and early flier. Present at many Gateshead sites, preferring smaller, sheltered water-bodies or slow moving rivers and streams. Good numbers at Kibblesworth Brickwork Pools, Gibside Lily Pond and Thornley Woods Pond, but best place for study and photographs is Far Pasture access road where the keen observer can find it in all stages of adult development amongst the roadside vegetation in late May and through June. Usually seen on ponds from late May to late August, latest record was Sept 5th at Thornley Woods Pond in 2012.

Two views of mature male Azure Damselfly
Similar to other bluets but in Gateshead only confusion species
is Common Blue damsel, and beware 'cos most sites hold both.
There are many subtle differences between Azure and Common Blue damsels, probably easiest to note in the field is the black marks on the end segment (see above) which are absent on the Common Blue giving it a brighter appearance at the tail end. But most often quoted is the shape on segment two of the abdomen. On the Azure it is a U-shape, on the Common it is a club or mushroom shape.

Close-up showing the U-shape on segment two of the
Azure damsel male
There are other subtle differences like two black lines on the thorax and narrower antehumeral stripes but if you are close enough to see these properly then the other differences should be apparent too.

This is an immature male, a striking mix of pale pink and mid-blue,
with chestnut-coloured eyes.
Males take on average 13 days to mature fully and only when mature will they
return to the breeding sites.

Females come in two forms, a green form (around 90%) and rarer blue form (around 10%)

Female Azure Damselflies
Green form (top) Blue form (bottom)
Note on the green form the dark dorsal colouring is complete,
whereas on the blue form gaps along the back show the
rich blue colouring.

This immature green-form female is typically pale
This is a teneral female of the green-form
(ie not long emerged, as told by the milky wings
which have not yet dried out properly)   

This individual is a bit of a quandary, having the complete markings
of the green form, but is quite obviously blue) 
Dispersal occurs at the immature stage, their first flights are vertical and high so prone to being blown quite long distances, and it's reckoned only 10-20% will stay to breed at the site from which they emerged. Any mature adult found will stay at that site for the remainder of it's short active life (unless high winds occur and they are blown elsewhere) which is only on average 5-6 days due to predation (though the longest surviving mature adult recorded is 26 days)
Azure damsels are fairly weak fliers, so tend to stick close to the margins of ponds where there is plenty of cover, and males aren't territorial, so will be found patrolling in numbers close to the water surface (usually near the shore) and perch near the top of plants to scan for females.

The Mating Wheel
This is formed when a male finds a female in pond-side vegetation
and takes place at the site unless there is too much disturbance from other
rampant males which will try to uncouple a pair and muscle in on the female.

Copulation takes around 30 minutes then its off to the pond
for a 90 minute ovipositing session (again if undisturbed) 

The male will stay firmly attached to the female during egg-laying in
the Sentinel position, to fight off potential rivals.
Eggs are laid in floating or emergent vegetation, and 2-3 hundred
will be laid in a typical session. 

Females especially are vulnerable during egg-laying, as they probe underwater they can be attacked by predators such as newts and diving beetles, but as long as their luck holds out, will return to the pond on every sunny day to mate and lay eggs.
Eggs hatch in 2-5 weeks and the larval stage lasts for about a year, emerging early summer the following year.

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