Sunday, June 10, 2012

California Darner

The earliest, and smallest, darner in our area is the California Darner.  Here's a shot from my recent trip to Cranberry Lake:

California Darner, male.  You can clearly see the "egg tooth" on the front of its thorax, which it uses to break through the larval skin when it emerges as an adult.

Notice the lack of a front stripe on the thorax, the cream-colored spots on the tenth segment of the abdomen, and the simple (blade shaped) appendages – all key features of California Darners.  Also notice that it is perched on the ground, another characteristic of these darners.  The other common darners in our area – Blue-eyed Darner, Paddle-tailed Darner, Shadow Darner – almost always perch in a bush at hip to shoulder height.  In our area, a darner on the ground is quite likely to be a California Darner, especially early in the season.

There were a dozen or more California Darners flying over the meadow and landing on the ground at Cranberry Lake.  When you walk through the grass you flush another darner every few steps.  At one point I saw a pair in tandem being chased by a single  male.  The lone male grabbed the male in tandem and they crashed to the ground.  The photos below show the pair in tandem and the lone male sitting on top.  After a few moments the male in tandem took off, displacing the lone male, and the pair flew high up into the trees.

A male California Darner on top of a pair in tandem.  Apparently it was trying to break up the pair so it could replace the original male.

The pair stays attached and takes off, displacing the lone male.

2 comments:

  1. How do you tell a California Darner apart from a Blue-eyed Darner?

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  2. A California Darner has no front stripes on its thorax and yellow side stripes. The Blue-eyed Darner has blue stripes on the front and sides of the thorax. Also, the California Darner has simple appendages, whereas the Blue-eyed Darner is unique in having "forked" appendages.

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