Monday, July 14, 2008

The Monday Dragon and Damsel Report - The Local Singles Bar

It seems I've been familiar with dragonflies and damselflies all my life. They are very common during the summer where I was raised. I always knew they were normally closely associated with water sources such as ponds, streams, and lakes, but that one could often see them some distance from an evident source of water. As I have watched the dragonflies and damselflies during this summer I have learned a lot about their habits and life cycles through observation and research. Some of what I learned is very specific to dragons and damsels, but much applies to the broader base of our natural environment.

I have taken to looking for dragonflies in other places nearby. I've checked around ponds and lakes and other water sources, but I was a bit surprised when I didn't find nearly as many dragons and damsels as I expected. Only one place of the several I visited came close to having as many dragons and damsels as our little pond. Eventually I figured out what I think is the basic explanation.

Just like all living creatures dragons and damsels have specific requirements to complete their life cycle. By chance of design and the seasonal weather our little pond just happens to provide most of the requirements better than some of the others I visited. Comparing it to the pond across the road is a perfect example.

Both ponds were built around the same time, but there are obvious differences due to the lay of the land, water sources, design, and normal recurring maintenance around the pond. One would think, however, that being so close they would have somewhat similar populations of dragons and damsels. Such is not the case. Our pond has probably 20 times as many dragonflies and a much wider variety. Why? It's because of procreation.

The pond across the road was beautifully designed and is well maintained. It is kept clear of most vegetation around the perimeter except at the head of the pond (the shallow end). Grass grows right up to the edge of the pond and is kept trimmed. There are two important factors though. The water level in the pond remains much more consistent and along the edges the drop off into the pond is much more steep. As a result there is little in the way of plants such as tall grasses growing at the edge of the pond in shallow water. Plus, the lack of a variety of trees and bushes directly around the pond means less plant matter such as leaves will fall into the pond and eventually float to the sides.

Our pond is different. All around the pond the banks slope down into the pond more gradually. Also, the water level fluctuates much more widely throughout the year. This gives plants around the edge of the pond a chance to grow at certain times of the year only to be covered up later when the winter rains raise the water level. Plus, we get much wider variety of plant matter falling into the pond and eventually drifting to accumulate along the edges.

Most dragonflies and damselflies lay their eggs in water primarily in or near vegetation. Dragons and damsels typically spend the greatest portion of their life in the water in the form of naiads which may go through several molts prior to emerging as the dragons and damsels we see. During their time in the water they need a variety of vegetation and plant material in which to hunt for prey and also to hide from predators.

Evidently we have more dragonflies because male dragonflies hang out around the primary breeding grounds waiting for females to show up. The pond provides not only a good supply of various insects they need to feed on, but also a preferred spot to lay eggs. I guess our little pond is like the local dragonfly singles bar, honeymoon suite, maternity hospital, nursery, and food market all rolled into one.

Let's raise a toast to bio-diversity and the importance of even the smallest ecosystems which give us creatures such as this.

12 comments:

  1. Hi Baker....so interesting....I love your pond, it looks so natural. The other pond looks clinical and a bit too perfect for my taste.
    To have the dragonflys and damsels must be wonderful.....

    I am surrounded by farmland here. In most fields, there are wildlife ponds....hence why the dragonflys visit me....I count myself lucky....

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  2. I guess our little pond is like the local dragonfly singles bar, honeymoon suite, maternity hospital, nursery, and food market all rolled into one.


    Interesting way of explaining it. lol


    Love the pond Baker.

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  3. I agree with Cheryl - nature is not always neat and tidy and with good reason. I think our instinct is for order and keeping things tidy but often that results in destroying exactly what other life forms find attractive.

    Great article Baker (as always :) )

    Just getting back on track after the weekend course. Exhausted but will gradually start doing my blog rounds again!

    *hugs*

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  4. Great post. I have always loved dragonflies.

    Your pond looks nature made. I like that.

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  5. Hi cheryl - always a pleasure to have you visit

    Rose - LOL - Yeah - I think that line about summed it up

    Avril - Hey there - Noticed you were absent for a few days but figured you were busy with the classes and all, Welcome back

    Tammy - Welcome and thanks for the kind words

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    A lot of the differences in the 2 ponds are a result of varying factors some of which evolved over the years. The construction style of each was based on the lay of the land. Also, the water source is different. Our pond fluctuates more during the year and is down considerably due to the unusually dry weather we had last year. I think the water table has dropped to a point where the springs that fed the pond are no longer running on a regular basis and the pond is highly dependent upon rainfall.

    The other pond has a fairly large watershed and is fed by a more consistent water flow so the water level remains more consistent. (Even that pond has been down a bit over the past year or so.)

    One consideration in building a pond in this area is what is it intended for. If it is intended for recreation such as fishing then it has to be accessible for people. Unfortunately we have to consider the 'S' word, snakes. Many ponds are kept clean and cleared along portions of the banks to make them safer for visitors. Our pond more or less evolved to a situation where the banks range from very clean and cleared to portions that are completely untouched and never visited. It seems to have worked out well.

    I think each pond is interesting in its own way. The photo does show the other pond as more neat and precise, which is the case around most of the pond. However, the head of that pond (the shallow end) is much more natural with woods growing down to the edge of the water and there is a small island with natural growth that provides a good nesting site for water fowl and other wildlife. Still, I don't think that end supports the dragonfly populations as well primarily due to the lack of sunlight. It is shaded during much of the day.

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  6. Interesting! I've been wondering about them lately cause this yr. for some reason I have alot of them in my yard/garden. my theory was they liked the hydrangas and the tomato blossom?? maybe it was the rainy late spring/early summer. i took some pics today, can't wait to see how they came out.

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  7. Hey rdl - glad you stopped by

    I'm not an expert in dragonflies or damselflies by any means, but I understand they are carnivores. I'm not sure if they are attracted to any particular type of plant as a food source. Perhaps they are feeding on the smaller insects that are attracted to the plants. I would think it is quite possible that a rainy late spring/early summer may have produced more of these smaller insects and the dragons and damsels are just taking advantage of that.

    I do often see dragonflies perching on the flower laden stems of some grassy plants, but I think it is basically to have a place to perch rather than the flowers themselves that draws them. Those stems are often taller than the grass itself and a bit sturdier and support the dragonfly better. Or maybe some have very small insects that the dragonfly can munch on though I think most of the dragonfly's meals consist of insects they catch in flight. Not sure on that one but it seems to make sense.

    Regardless, I hope your photo's come out good. I look forward to seeing some of them.

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  8. Baker - wow again! and wow!
    I have found that observing them is so much fun and has led me on a great path!
    My canal is the same as your pond - much more "natural" and not trimmed so they seem to like that and the big empty field.
    Your pics are gorgeous - so clear! Is the damselfly laying eggs?
    I want to try and find some of the naiads near the canal!

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  9. Thanks again London Yankee

    Yes - the damselfly is laying eggs - many species will lay their eggs in tandem - I think this is the male's way of making sure no other males interfere or have access to the female until after the eggs are deposited

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  10. what an amazing capture! I am going to spend some time by the canal this weekend and I would love to spot a new dragonfly emerging!

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  11. That's interesting. The two photos really illustrate the differences between your ponds. Thanks for the info, your pond does seem very interesting!

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  12. Thanks brine queen. I thought you might like this little assessment of the pond given your background. It is definitely interesting despite its small size. There's always something going on it seems at this time of year.

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Thanks for stopping by to visit our little pond. We would love to see you again real soon.