Thursday, 2 July 2015

The southern hawker dragonflies and the hailstones


Southern Hawker dragonflies, Aeschna cyanea, have been emerging for the last week. I’ve only found a few of the old cast skins, called exuviae, so far, spooky and forlorn still clinging to sedge and reed stems as if they may be reanimated and crawl back into their ponds, but I’d not spotted any adults. Until today. Our region was hit by ferocious thunder storms last night, with hail stones the size of musket balls ricocheting around our back yard. This morning two newly hatched hawkers, maybe a bit subdued by the ominous weather and still not fully coloured up, were clinging to the cover of iris and reed stems at a nearby pond.  They will soon acquire the vivid bright green or pale blue bands that make them a very colourful insect.  As they whizz past I’ve heard startled passers by mistake them for very large wasps. The two conspicuous patches on the top of the thorax are particularly useful for identification. Once hatched and coloured up they will be away, often hawking along paths and woodland edges and taking their time before heading back to the wetlands of their birth. If you can get over the panic of “a very large wasp” take your time with them; the southern hawker is well known for its habit of inspecting you with as much interest as you might take in it. They will repeatedly fly up to you, check you out and seem as intrigued by your presence as you might be by their beauty. “Southern” is a bit of a misnomer. They are now quite at home this far north as this map from the nbn gateway shows : the yellow squares are 10x10 km grids from which the species has been recorded source, https://data.nbn.org.uk/Taxa/NBNSYS0000005626)

No comments:

Post a Comment