Damselflies: three questions, two answers

Fragile Forktail Damselfly at the Wetland, 4/12/2021

 Question 1: What's the difference between a dragonfly and a damselfly?

This is a question that many people have. I created a brief video explaining the differences back in 2020, which you can view at https://flic.kr/p/2jnAnbN. In brief though you can tell that the creature in the photo above is a damselfly because it folds its wings together above its back. Dragonflies never do this except when they have first emerged in their adult form (examples of this to follow later this season). Dragonflies at rest hold their wings straight out to the sides like airplane wings. In addition, damselflies are smaller and weaker fliers than the closely related but more robust dragonflies. Also, most dragonflies that are commonly encountered* have eyes that are so big they at least touch each other and most have eyes that meet in a long seam between them in the center of the head. As you can see in the photo above, damselflies have eyes that are widely separated.

Question 2: I saw the first adult damselflies, like the fragile forktail pictured above, at the wetland this year on April 9th. Where did they come from? Did they in their aquatic phase of life last year survive the dried out pond to emerge this year or did they come from somewhere else?

This is, so far, the unanswered question. It is possible that the fragile forktails seen flitting about at the wetland emerged at the lake and came over to the wetland. However, damselflies, unlike dragonflies, are not strong fliers and do not normally cover a lot of ground. Four hundred feet is not that far but is still a considerable distance I think for little damselflies. In addition, I have not yet seen any damselflies at the lake edge itself, but have not spent a lot of time looking. The question is further complicated by the fact that two nights ago the temperature in the Homer Lake area was freezing or below for about 8 hours and then again early this morning the temperature dropped to at least freezing for a couple of hours.  I did not see any damselflies flying at the wetland today and I saw only one dragonfly, most likely a common green darner, over the meadow where there have been numerous in recent visits. I think it likely that the freezing temperatures took their toll on the migrant dragonflies and early damselflies. On other days recently with temperatures in the 50's as they were this afternoon I have seen both dragonflies and damselflies active at the wetland. The early arrivals, both migrants and early emergers, may have been wiped out.  Still looking for answers to this question.

Damselfly Naiad from the Homer Lake Wetland, approximately 1/2" in length, 4/14/2021

Question 3: Since I only began seeing adult damselflies at the wetland this year on April 9th, where did these relatively large immature damselflies ("damselfly naiads") come from that are all over in the pond?

Answer: With some guidance from others who know damselflies better than I do, I have been able to identify these naiads as being from the spreadwing family of damselflies (damselflies that hold their wings slightly open rather than closed over their backs or completely spread like dragonflies do). Damselflies in general lay their eggs inside plant stems, but spreadwings are known to overwinter as eggs and hatch in the spring. In the case of our ephemeral wetland, this not only gets them through the winter, but also through the dry spell when there is no water. When the eggs hatch, the new spreadwing naiads drop into the water out of the water plants the eggs were laid in. This accounts for these naiads being the size they are -- they are from last year's eggs.

*The clubtail and petaltail dragonfly families also have eyes that are widely separated, but these are not commonly encountered by casual observers.

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