Common Darter



Sympetrum striolatum

Common by name, common by nature. I doubt if there's a site in Gateshead where this obvious dragonfly isn't present at some time over the summer, and usually in good numbers.
Though emergence begins in late-May I've found they don't tend to become numerous at sites until mid-July; I find Kibblesworth best for seeking out tenerals and immatures, but best for study and photographs is Far Pasture, where on good days there can easily be 50+ basking on the access road, fences, and in the adjacent fields. Later in the summer is usually best to see mass ovipositing on the pond and they will be present as long as the autumn stays mild, my latest ever record being November 4th.
Stargate (sheltered bog pond) and Burdon Moor also usually hold good numbers, but look out for them anywhere, also a common visitor to the garden, a good distance from water.
The only confusion species is the Ruddy Darter but a decent view will show a number of diagnostic differences.


Common Darter (mature male)
Orangey/red abdomen, yellow thorax panels and yellow stripes on legs
should all be visible from this sort of angle. 

Away from the pond they will perch on any good vantage point when
feeding, or on the ground when they are warming up.

This pic. shows the black line over the frons only stretches across the top,
as opposed to most other darters (including Ruddy) where the black goes
so far down the sides as well.
 

Note the yellow stripes on thorax and legs, on Ruddy
they are uniform brown and uniform black. 
Like most darters, the immature male Common is yellow and could be
mistaken for a female, check the anal appendages to make sure. 
This individual is not yet fully mature, still showing yellow
patches on the abdomen, gradually turning orange.
Note also from this sort of angle the abdomen tip can look bulbous
like that of a Ruddy. . . .

. . . but looking from above would show the abdomen has more or less
parallel sides.


This male is in the 'obelisk' position, or sky-pointing
Many darters do this to cool down on a very hot day, pointing
the abdomen directly at the sun reduces the surface area
receiving direct sunlight. 
Common Darter (mature female)
abdomen is fatter than that of the male and has black markings along
the upper-side of the mainly yellowish/brown body.

Close-up shows stripes on legs and minimal black line over frons.

Teneral female, just emerged.


Over-mature females turn reddish along the abdomen and in
cases of extreme longevity you might find an individual which
is almost black.

 
Males seize females as soon as they arrive at the pond. At high density
sites males will be flying almost continually and there will be a mad
scramble for any female entering the scene.



Copulation can take up to 15 minutes, usually low down
in vegetation . . . . 
. . . . . or sometimes high up in trees.

ovipositing is usually in tandem (but not always)
the pair repeatedly dip into the pond, eggs
washing off the tip of the female abdomen 
Egg-laying takes place at roughly one dip per second for around 5 or 6 minutes. When done the female raises her abdomen to about a 45 degree angle and the male releases her.
Eggs laid by September will probably hatch in about 2 weeks, but later than that will most likely over-winter and hatch in the spring, development takes one year.
 
 







































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