Dragon and Damselflies

“Dragonflies are marvels of aerodynamic engineering. The adult beats its two sets of wings out of phase and can control both frequency and amplitude. The angle of the two sets can be controlled independently, allowing for some astonishing aerial manoeuvres, spectacular hovering and flight in any direction. Dragonflies love the world’s wet places as their nymphs remain aquatic for months or even years.” (quoted from BBC Nature)

There are 40 species of breeding dragon and damselfly in the UK and this is added to by the few migrants which turn up in the summer months. Feeding only on live insects, they consume about 10 – 15% of their own body weight a day. They catch their prey either by hawking (catching insects in midflight in the air) or by gleaning (hovering above vegetation and dropping briefly to snatch insects perched on twigs or leaves). They are most active from June to September and their hawking patrols mean you can sit and watch them coming back and forth – perhaps trying to catch them on camera!

Dragonfly sex involves an unusual step – the male must transfer the sperm from the tip of his abdomen to the storage reservoir at the base of his abdomen. The female dragonfly is inseminated when her genitalia make contact with the male’s accessory genitalia, not the genitalia at the tip of his abdomen. The shape formed by their bodies when this happens is know as the copulation wheel – there is a photograph of Red-Eyed Damselflies demonstrating this in the Gallery.

The weather since June 2012 has only offered a few days when the dragon and damselflies are out. But there’s still plenty of time and we know, from last year, that there are many more species on the Marina.

 

 

 

 

05. July 2012 by Jo
Categories: Invertebrates | Tags: , | Comments Off on Dragon and Damselflies

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