Southern Hawker

Aeshna cyanea

Our most colourful hawker, the male being a lovely combination of blues, yellows and greens. Usually emerges early July though I have seen one fully mature in June before.
Through August, September and early October they seem to be the most common hawker locally, appearing literally anywhere (I always have a few flying through the garden).
They hawk along the river Derwent and are seen at just about every known pond in the borough, regularly at Far Pasture and Gibside, but the best site for them by far is Thornley Woods Pond, an intimate little site where all aspects of their life history can be observed, including from early July the fascinating sight of the emergence.


Southern Hawker (mature male)
A striking insect, larger spots than the other hawkers in a line
of green turning to blue along the back of the abdomen.

From above note the thick antehumeral stripes, much thicker than those
of the common hawker, and the blue bands at the tip of the abdomen
are also unique to the southern hawker.
Note the female has the same thick antehumeral stripes
Abdominal colouring is a duller green on brown, and has tail bars
like the male. 

From the side note how the thorax is made up of green
panels, rather than the stripes of the other hawkers,
but not as complete as the Emperor.

A close-up of the intricate markings of the male shows the
waisted abdomen.
In flight it should be possible to get good views with a little patience
as the southern hawker often hovers in front of an observer as if
checking you out. Feature like colouration, antehumeral stripes, thorax
and blue tail bars should make for easy identification.
In silhouette the abdomen is held with a slight downward curve.
 
Compare the profile of the female (above) with that of the male (top)
Thorax is pretty much the same but the abdomen is thicker and has
green on brown markings.
Southern Hawker (mature female)
The female is not so colourful as the male but distinctive from other hawker
females with greenish spotting and panelled thorax. Unlike other hawker
females she also has thick antehumeral stripes.   

It is often possible to get really close to a female as she oviposits.
The Southern Hawker is commonly found in woodland ponds, lakes, canals, and garden ponds. Adults spend most of their time feeding in woodland rides, hedgerows and gardens. Males are territorial but will 'time-share' a territory, zipping in for a stint of anything between 10 and 40 minutes searching for females, then if unsuccessful, leaving again. Fights break out when the next male arrives at the pond. If the male in situ has only been there a short while he will defend vigorously, if he's been there a while he will allow himself to be chased off.

Younger females will arrive at the pond in the mornings to have a better chance of mating, older individuals tend to arrive in the afternoon, and they visit only once or twice every three days. Non-receptive females (those who arrive only to oviposit) will still attract attention, but will flee and hide or attempt to struggle free if caught.

A male will either search the margins until he comes across a waiting
female, or seize one when she arrives at the site. He will clasp her by the
neck and form a mating wheel while carrying her off into the treetops,
where copulation may last up to 2 hours.   


The female oviposits alone, and will usually come to the pond early
morning or late afternoon, or midday on cooler days when there is
likely to be less male activity.   

Eggs will be laid on submerged plants, logs or tree roots, muddy banks, moss, wooden bridges and boardwalks, indeed almost anywhere.
Eggs remain dormant through winter and hatch early next spring, the larvae emerging the following year from mid-late June, peaking in July.

The soft-bodied larva climbs up a plant stem then waits
to dry out.

The dry casing splits at the 'shoulders' and emergence begins 

Head and thorax forced out first

Then the abdomen is inched out 

The legs harden ready for use in the next stage

The dragonfly reaches up and pulls out the
remainder of the abdomen

Now completely free of the larval casing
which it hangs from to dry out.

The abdomen begins to stretch out and
the wings begin to unfurl.

The wings slowly pump up and the first sign of
colour can be seen in the abdomen

Slowly the dragonfly is taking shape


Still a way to go but the wing-veins,
nodes and pterostigma are all there
to be seen. 
The whole process of emergence to the first flight of the teneral dragonfly takes a few hours and is mostly done at night as the young dragonfly are very vulnerable at this stage to predators, but I've witnessed it many times through to late morning.

The freshly emerged dragonfly of both sexes is a pale cream colour,
this one is a male told by the waisted abdomen   

This emerging hawker will be a female, the much thicker base to
the abdomen the tell-tell sign.
When the wings are fully formed and dried out, the teneral dragonfly will warm them up by vibrating them thoroughly, and take a first tentative flight into trees or vegetation, where they will remain until their wings gain strength, then will start living the life of a full adult hawker, feeding in woodland rides for a few days until they gain their full adult colours of maturity.

Back at the pond, this dried out husk (exuvia)
is all that remains to tell the tale.
To end; a couple of rarer colour forms to look out for in the mature adults. Males can sometimes have totally blue spotting on the abdomen where there is usually green. This will lead to confusion with other species, but still look out for the bars at the tip of the abdomen, the thorax will still be the apple green shade and the thick antehumeral stripes should be apparent.
In females there is an occasional yellow form which again might lead to confusion with other hawkers, but as in the male, the antehumeral stripes, thorax panels and tail bars all remain consistent.










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