Sunday, 3 July 2016

Sunday 3rd July 2016

There be more Dragons.....


This morning has seen a "mass" emergence of Common Darter dragonflies from the garden pond, with eight new individuals either emerging or drying off.

Considering the pond is only 12 months old this week I'm really pleased that so many of the eggs I saw being laid in the late summer of 2015 have developed and emerged, over 30 individuals have made it to the final stage so far.

The Common Darter, Sympetrum striolatum, is one of our commonest members of the Odonata Order of insects belonging to the Suborder Anisoptera, (damselflies the smaller weaker looking bedfellows belong to the Suborder Zygoptera). 

They can develop from egg to full grown dragonfly in as little as three months, given optimum conditions in the pond, although eight to twelve months is more likely.

Not all will make it to maturity with plenty of obstacles in the way of success, not least of which is the prevailing weather, high winds may result in newly emerged individuals ending up in the water where they drown.

The photos show some of the stages of emergence.


Tall emergent vegetation for the larvae to crawl up away from the water

Having broken out of the larval case, the newly emerging dragonfly,
hangs waiting to pull its head and thorax upright
This stage is maybe a few hours later when the body has distended but before the wings are fully pumped
The wings are drying ready for the maiden flight, at this stage the newly emerged
dragonflies are "water averse" and actively fly away from the water, its safer!
Two examples of exuviae, (the empty laraval cases)
 The one on the left is of the Common Darter, Sympetrum striolatum
The one on the right is of the Southern Hawker, Aeshna cyanea

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