PLANTS | ANIMALS | ECOLOGY | FUNGI | GEOLOGY | GARDENING | TOOLS
Excerpts from Jim Conrad's
Naturalist Newsletter
from the August 5, 2012 Newsletter issued from the woods of the Loess Hill Region a few miles east of Natchez, Mississippi, USA
BLUE SKIMMER DRAGONFLY
The day before last Saturday morning's cloudburst, which dumped 6.13 inches (5.7cm) of rain on us and washed away my campfire's hissing kindling before the cornbread got done, a dragonfly landed on a snag in the orchard. That day before the rain I wondered what a dragonfly was doing so far from any standing water, though it was true that a dry pond lay just downslope. I photographed the insect, taking care to keep the wings in focus, for vein configuration in wings often is determinative in dragonfly identification, and I was thinking that this might be an unusual species adapted for waterless upland habitats. That's the resulting photo above.
My dragonfly field guide soon revealed that our orchard visitor was one of the most common and conspicuous of skimmer dragonflies, the Great Blue Skimmer, LIBELLULA VIBRANS, mostly distributed in the US Southeast but occurring as far north along the coast as Massachusetts, and inland through most of Illinois. This species' most distinctive feature wasn't to be found among details of its wing venation, however, but rather its black wingtips, easily seen from a distance.
So, once you have something's name, you can look up what's special about it. My field guide describes Great Blue Skimmers as a "regal" species, often tame, allowing a close approach as it perches on a shaded twig -- exactly as was our case. It frequents swamp pools and slow forest streams, including temporary ponds, again exactly right for ours, since the next day a temporary pond did form not far away.
The name "giant skimmer" is given to members of the genus Libellula, of which about 23 species are recognized in North America. Male giant skimmers hover-guard egg-laying females, which usually splash their eggs onto banks.
Our orchard skimmer is a female and I just wonder: Did she really know that the morning after her visit there'd be a tremendous rainfall that would fill the then-empty pond just downslope from where she perched? The future pond was actually in her line of sight as she perched.