Friday, 8 August 2014

The creeping up on red darter dragonflies time of year

Red Common Darter dragonflies, Sympetrum striolatum,  may not have the glamour of their bigger brethren such as piratical Emperor Dragonfly or gaudy Southern Hawkers but there is an everyday charm and confiding jauntiness to them that conjures up August (...with an ominous hint of approaching autumn too). They are fond of basking on wooden fences and tables in the sunshine and they soon circle back to their perches if you disturb them. Creep up carefully and you can get very close. Often they waggle their heads, sometimes holding an inquisitive sideways look at you as they try to work out what you are. Their huge eyes, made up of lots of separate single facets called ommaditia, are very good for detecting movement as the shadow you cast crosses from each facet to the next. If they are not in the mood for being crept up on they will depart but they seem to appreciate the warm days of high summer as much as we do and mostly can’t be bothered. Their larvae are rather squat, sprawling critters, again lacking the submarine menace of the larger species. Instead they clamber amongst the debris and submerged plants in ponds.  There are several very similar species of red darters, including migratory rarities such as the Red-Veined Darter, but this far north most of them are the Common red. this one has the typical large yellow splashes on the side of the thorax which are a good ID tip. Black Darters turn up along the Bay sometimes too: they are small and fidgety compared to their red cousins. Darter Dragonflies will last long into the autumn if the days stay warm, but right now are busy enjoying the sunshine, whipping in tight, dog-fighting circles as males vie for supremacy or hovering briefly on the look-out for a mate. Autumn can wait.

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