Saturday, September 10, 2011

September 10, 2011

Unfortunately, after my last post, the rain didn't stop, and the lake level rose again, by another 2-3 inches.  By Friday it was over the gauge at the dam, showing maybe 14 inches above full level.  But it has now started to drop again, and with the cool, dry weather over the weekend, there is a fall feel in the air.

On one of the cool, damp mornings before it dried out, I saw this view from Crocket's Ledge of Gunstock and Belknap mountains rising above the ground fog.
Gunstock and Belknap Mountains from Crockets Ledge

I also found a red-backed salamander resting on top of a bright red mushroom!  The amphibians must be having a good time right now with all this wet weather bringing them an abundance of food and wet habitat to enjoy.  I have seen many red efts all over the forest.  Surprisingly, considering all the rain, the mosquito population has dropped off significantly, so that walks in the woods are much more enjoyable.  It's another sign of summer coming to an end though.
Red-backed Salamander

I noticed a large, bright dragonfly hovering around the lake after the sun came out, and decided to see if I could identify it.  I was only partially successful (my best conclusion is a blue-eyed darner), but in the process I learned that some dragonflies are migratory.
Blue-eyed Darner

One report I read (see it here) said that during migration dragonflies can travel in excess of 400 miles over a two month period, including single-day flights of over 90 miles.  How do they know this?  Researchers attached miniature radio transmitters to the insects, and then tracked them in airplanes for the ten days that their batteries functioned.  They then extrapolated from there.  They also found that during migration the insects would fly one long day, then spend two days resting and feeding.  Some dragonflies migrate in large flocks like birds, taking advantage of favorable winds to help push them in the direction they want to travel. 
A darner with its transmitter attached. Photo by Christian Ziegler and taken from sciencenow/2006/05/ 11-02.html?etoc&eaf

I also got a look at a small damsel fly - it gives you the idea where the term "bug-eyed" comes from:
Variable Dancer

And remember that dragonflies are predators, feeding on other insects - including mosquitoes - so be welcoming to them when you see them around Lake Wicwas!

Literature Cited:

Wikelski M, Moskowitz D, Adelman JS, Cochran J, Wilcove DS, & May ML (2006). Simple rules guide dragonfly migration. Biology letters, 2 (3), 325-9 PMID: 17148394

1 comment:

  1. Hmmmm... that sweatshirt looks familiar... so glad I could model for you.