Wednesday, September 10, 2008

Bass Ponds Dragonflies

On Monday July 14th it was a nice day so I decided to go and visit the Bass Ponds after work. In midsummer there is not usually a lot of birds around the Bass Ponds, but there are sure a lot of pond dwelling dragonflies to photograph.
The twelve-spotted skimmer is named for the black spots on its wings. You can see from both the picture above and the picture below that each of the four wings contains three black spots for a total of twelve all together. The male twelve spotters also have white spots in between the black spots so both of the pictured twelve spots are male.
Twelve-spots are pretty easy to photograph. Since they are fairly common dragonfly through out most of North America, except for the extremes, they are usually pretty easy to find. There size and the fact that they like to perch on the tops of sturdy vegetation also aides in finding this species. The best part though is that if you get to close and flush a twelve-spot chances are he will come back and land in almost the exact same spot. So all that you need to do is sit and wait.
The eastern pondhawk is not quite as easy to photograph as the twelve-spot. They are much less common and prefer to hunt from the ground, as pictured above, or a low perch. Females and immature males are green, but as the males mature they gain a powder blue pruinosity which begins from the end of their abdomen and eventually covers most of their body.
It is a bit more difficult to see the spots on the four spotted skimmer then on the twelve-spotted. The spots are the stigma, small colored patch at the end of every dragonflies wing, which is black and a heavy black nodal spot. The nodal spot is where a cluster of veins join together near the center of the front edge of each wing. All dragons have a nodal spot although on most it is not as visible as it is on the four-spotted. The four-spotted skimmer pictured above is probably pretty mature, you can tell because it has lost most of the color in its wings and its abdomen is fairly dark.
I think that it is strange that they call them four-spotted skimmers. Since they have 2 spots on each wing they actually have a total of eight spots, if you count them the way that twelve-spotted are counted.


Shellmo said...

On your 12 spotted - I was actually counting the spots - neat! Really enjoy your dragon fly posts.

Leedra said...

All are good as usual but the 12 spotted are so great! Just from the correct spot.

Ecobirder said...

Thanks Shelly and Leedra, hopefully this will help you ID a twelve-spotted the next time you see one. They are fairly common through most of the US so you can probably find them around where you live. Only problem up north here, probably in Michigan too, is that it is a bit late in the year for most of the pond species.