Four-Spotted Chaser

Libellula quadrimaculata

Common, early season dragonfly. Inhabits a wide variety of still waters and can be present in large numbers at established sites.
In Gateshead, Kibblesworth Brickworks Pools holds by far the largest population, but small numbers can be found at Stargate, Far Pasture and Gibside, with the flight season being late May to early August.


Male Four-spotted Chaser
In the field they are dull in colour but conspicuous by behaviour, perching
openly, speeding out over the water to feed and chase rivals.
Diagnostic dark wing-spots at the nodes give them their name.
 
 Male four-spotted chasers are highly territorial and aggressive. Territory holders find a favourite perch from which they make frequent sorties to feed, fight off rivals and search for females. But at ponds with large populations, territories break down and they spend most time on the wing, where they are a sight to behold on a sunny day with seemingly non-stop dog-fights between males.


Another male, though sexes are alike, immature females are a lot brighter,
dulling with age, when they can be told apart by the slightly fatter abdomen
and longer, inward-pointing anal appendages.

 
Females aren't easy to photograph as they spend much of their time away from water, and when they do come to the ponds they are harassed continually by males, so finding a settled one is quite unusual.


Emerging Four-spotted Chaser
Takes place on marginal emergent vegetation usually
in early morning late May and through June.
Larvae take two years to develop.

This picture shows the much more colourful thorax, and note the
dark smudges trailing from the pterostigma, making this individual
the rare prenubial form, though the reason for its existence
is unknown.

This unfortunate male was plucked from the sky at Kibblesworth by a
female Emperor. Apparently this is quite common as both species
patrol at similar heights (70-100cms) making encounters inevitable. 

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