Blue Dasher

Here's another Blue Dasher. It lacks the blue pruinose of a mature male, but is it a female or an immature male?

The more I read about this, the harder it is to distinguish between mature females and immature males. I think this is an immature male because the eyes look blue (though most documentation describes their eyes as green), definitely not the reddish eyes of most females. But some older females apparently develop greenish eyes. On the other hand, some older females also develop some of the pruinose that usually distinguishes them from males. Maybe the biggest difference between the sexes is the tail, which looks a little stumpy in females.

I'm leaning towards an immature male since:

  1. It has the right eyes, the lack of pruinose, and the tail doesn't look especially short.
  2. If it's an older adult female, she's got the right eyes but lacks any pruinose. And I think the tale would look shorter.
  3. If it's a normal mature female, she's got the wrong eyes and probably has too long of a tail (though the lack of pruinose would be about right).
In some species there's a better way to distinguish the adult females from immature males, but that doesn't seem to be the situation with the Blue Dasher.

August 17, 2020 at Duke Farms


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