Saturday, June 11, 2016

Damsel

In distress? I hope not. We love our dragonflies, a larger relative of the damselfly. They fly around eating all kinds of insects, sometimes landing on our shoulder, and sun themselves in the morning on the side of the house. Since damselflies are diminutive compared to their larger cousins they can easily go unnoticed. Because they are particularly fond of the arching leaves of our garlic, I see them quite readily. Today I took a close look and found that they came in three colors.



Blue



Green 



 And pink.

There are roughly 5000 species in the insect order Odonata of which Damselflies and Dragonflies belong. A good way to tell the difference between the two, other than size is the way they rest. Dragonflies rest with their wings spread while damselflies rest with wings together and parallel to their body. Each has incredible visual acuity -80% of their brain is used for visual analysis (the giant eyes). They are also incredible fliers able to fly quickly forward, backward, and hover. Few insects that can make you feel like you live in a magical environment, but these do (butterflies being another), especially when they arrive by the hundreds.

Having plenty of Odonata species means that your wetland habitat is relatively unpolluted. This year we have had an unusually late start to the mosquito season, not having seen any until about two weeks ago. The control agent who tests our wetland found no mosquito larva in middle May -again, highly unusual. What this means is less pesticide spraying in the area that undoubtedly kills Dragons and Damsels as well as mosquitoes and what else. I do not know if the Bt drops, made by helicopter, kill Odonata species as well as mosquitoes in the larval stages. Quick searches suggest no, but maybe inconclusively.




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