Tuesday, September 2, 2008

Serendipity

As some of you may know most dragonflies and damselflies spend the greater portion of their lives as nymphs (or naiads to be technical) living in water. After going through several stages (instars) where they shed their outer skeleton, they eventually emerge from the water for the final transformation into the dragons and damsels we are familiar with. For most species the naiads crawl from the water and ascend some type of vegetation or other surface in or near the edge of the water. The naiad then splits open its exoskeleton (outer shell) along the top and emerges head and thorax first.

This emergence is a crucial period for the dragons and damsels as it may take some time (at least an hour and sometimes longer) until the body emerges completely and the wings become extended and dry. During that time the dragon or damsel is very vulnerable to predators, rain, wind, and other dangers. Being unable to fly they have no way to escape or hide.

If you check around the edges of a pond or some other water source where dragons and damsels breed you may find the empty shells (now called exuvia) they leave behind. Around our pond I frequently see exuvia on sticks and blades of grass. (I presume most of these were left by dragons and damsels though it is possible that some could be of different insects.)

I have tried to spot the emergence of a dragon or damsel, but I understand that many dragons actually emerge at night. Damsels, it seems, often emerge during the day. Just a few days ago I happened to be photographing a spreadwing damselfly and when I downloaded the photographs I was surprised to see that I had also captured the emergence of a damselfly off to the side. While that portion of the photograph was not in perfect focus, I decided it was well worth sharing on the blog.

You can see it has just emerged and the head and thorax (the main part of the body where the wings are attached) are clearly recognizable. The rest of the body and the wings are still wet and covered. At this stage the damsels do not display their eventual coloring and they are difficult to identify by species.

I only wish I had noticed this one when I was actually there at the pond, but it was one of those cases of leaning out over the water at an odd angle trying to get the photo of the spreadwing (which I got by the way and it was in focus) and I just was not looking for the emerging damselfly.

5 comments:

  1. Thank you so much for sharing the wonderful photographs.....for me they are such a treat.....I love coming here to learn from you.....amazing

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  2. Good info, I'll be going down to the beaver dam to check it out.

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  3. Yes truly wonderful photos!

    While mowing our backyard this weekend there where several sets of what I would call dragon flies; although I don't know if that would be correct; flying around me. I was kind of worried that they would fly into the riding mower. I thought about running inside to get the camera but I knew they wouldn't just pose for me and I didn't have time to sit quietly and wait for them to come near. Maybe next time.

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  4. Thanks so much cheryl

    bob - hope you have luck finding them - it all depends on the season and the species of course - we still have some emerging but I think perhaps it will come to an end fairly soon when the nightly temps fall

    ladykli - I would say there is a good chance they were dragonflies - they forage where there are plenty of smaller insects which might be attracted by the mature grass which might have gone to seed as it is likely to do at this time of year

    Baker

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  5. Oh wow Baker..what a fantastic opportunity and to have the camera. Bravo...

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Thanks for stopping by to visit our little pond. We would love to see you again real soon.