Broad-Bodied Chaser

Libellula depressa

A colourful, medium-sized dragonfly of early summer, and relatively new to Gateshead as only 15 years ago it wasn't even known to breed north of the Humber.
But it is a well-renowned wanderer which can be found in almost any habitat, but prefers shallow ponds with no shade, and in Gateshead the primary breeding sites have been Stargate Ponds and Burdon Moor with just occasional sightings at Kibblesworth Brickworks Pools, but in 2013 was also discovered at Far Pasture and Milkwellburn Woods.

Male Broad-bodied Chaser
A real beaut with that powder blue abdomen and dark red/brown patches
on the inner wing.

Side view of the mature male shows the yellow side-lights.
Immatures can be mistaken for females as the abdomen of both
sexes starts off bright yellow. 
Female Broad-bodied Chaser
The female abdomen matures to brown, the older the lady, the
darker she gets, but keeps the yellow side-lights.  
 

Male (top) female (bottom)
The female abdomen is fatter and more rounded than the male, in flight
they have a side-to side approach action and the yellow side-lights make them
look like gigantic wasps as they approach a perch.
 

Note this male standing on only four legs. Look carefully and you can see
the front legs curled up ready to snatch prey (or a passing female)
in this alert posture.  

The blue of the male abdomen isn't the colour of the abdominal
casing but a pruinescence, which is a blue (or grey) waxy bloom, and
parts get rubbed off each time they mate, so older specimens which have
been 'successful with the ladies' show large areas of black. 

A male will snatch a passing female from his perch and mating takes place in mid-air usually, lasting only a few seconds so not easy to photograph.
The female will then oviposit, repeatedly dipping the tip of her abdomen in the water, washing off eggs each time, the whole process of mating and egg-laying taking just a matter of minutes to complete.
Males will watch over the egg-laying female, often hovering close-by to ward off other potential suitors; newly mated males then tend to be more aggressive and will fight to keep a territory.

Eggs hatch in 2-3 weeks and larvae mature in 1-3 years depending on the state of the pond hampering the rate of growth. As they like shallow ponds, drying out is a problem, solved by the larvae burying into the mud and lying low 'til it fills up again, even over-wintering like this. 

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