Assuming all goes well, however, the dragonfly begins to pull its body out of the nymphal exoskeleton. I saw two different methods of this. This blue dasher female freed her legs, then used them to grasp the stem and pull the rest of her body out:. The female eastern pondhawk, however, started bending her body over backwards, using gravity to help pull her head and thorax down to extract her abdomen:.
Both dragonflies eventually rested on the plant for a while, pumping hemolymph into their wings to extend them fully. The blue dasher sat above her exoskeleton:. The pondhawk was too close to the water to extend her wings fully, however, so she eventually moved up the stem so that she could finish her wing development and stretch them all the way out:.
Those little white strings hanging out of that shed exoskeleton is the shed respiratory system. I never get tired of marveling at just how amazing it is that insects replace whole systems when they molt, both internally and externally!
At this point, the dragonflies began to harden, their bodies darkening in color until they approached their final color. The blue dasher female was a dusky black:.
The eastern pondhawk became an even more vivid green and her black markings became dark and vibrant:. The whole process took about three hours for each species. Eventually, the 10 successfully molted new adults all flew off, ready to spend their short lives on land and leaving their old lives behind:.
What an amazing process! If I had to spend a Saturday at work and a very long Saturday at work at that , these sorts of things make it completely worth it. I was thrilled I got to see all these dragonflies emerging. Every time I go into the garden now, I am drawn immediately to the pond. Will there be more dragonflies emerging? Thanks for sitting out there watching dragonflies emerge. This is SO cool. Thank you for taking the time to watch all this and post about it!
Look for dragonfly nymphs crawling up the stems of plants in the water — you just might be able to see it yourself! Wonderful set of pictures capturing the wonder of the nymph-to-dragonfly metamorphosis process!
Thank you for sharing! I was so glad I had a camera on me for once so I could actually document it. Glad you enjoyed the post! Those are amazing shots and your commentary really helped me to follow what was going on. After a series of 90 degree days last week, we seem to have lots of dragonflies, but I will keep my eyes peeled for the exoskeletons and maybe I will have the good fortune to see the process unfold.
Great pictures! It goes back to the old world notions that dragonflies are in league with the devil. Honestly, I have no idea where the image came from. I can only imagine that there was a body of water that had a lot of snakes in or around it and the dragonflies were thought to be associated with them somehow.
Thank you very much. Seriously, I am pursuing a lot of nature stuff and yours is right up there with the best. I liked that as soon as the last ladybug hunter left you went right back to where the action was. Your pictures are great, you enthusiasm is great, and your knowledge is great.
I do love my dragonflies, so I spend a lot of time watching them. Glad my enthusiasm for them comes through in my writing. Sorry to hear about the book situation though. I have to see this for myself. Thank you. I hope you will be able to see it! Truly phenomenal piece! Thanks for taking the pictures and all the time to document and explain…so great to have it all together here in this one blog!
So glad that you enjoyed it! Thank you so much for taking the time to create the images and craft the text to so clearly document and explain Dragonfly metamorphosis. I will be sharing this! I love your posts. This one was wonderful. I have photographed a truly unusual looking dragon fly and would love to send you a photo. It has an interesting look to it that I have not seen before. Dragonflies spend most of their lives in their larval stage. During its time the dragonfly catches and eats live prey at every opportunity, moulting a further 5—14 times until it is fully-grown.
Larval development typically takes one or two years, but ranges from 2—3 months emerald damselflies to more than five years Golden-ringed Dragonfly. Development takes longer in cooler waters where food is scarcer, whilst in warm waters there may be a new generation every year. Damselfly larvae can be separated from Dragonfly larvae by their caudal lamellae, which are fin-like structures at the end of their abdomen that act as external gills.
All dragonfly larvae have six legs as do adults , wing-sheaths, an extendable hinged jaw labium that can shoot out in an instant and catch prey. Prey includes insect larvae, crustaceans, worms, snails, leeches, tadpoles and small fish. Dragonfly larvae themselves can fall victim to predators, including other dragonfly larvae, fish and waterfowl.
The larvae of some species are covered in hairs that collect silt or organic debris from the soft sediment within which they live. Species living in bottom sediments have relatively poor eyesight, but instead use their hairs, long legs and antennae to sense prey.
By contrast, hawkers have large eyes and hunt by sight amongst plants nearer the surface. Dragonflies undergo incomplete metamorphosis ; unlike other winged insects, such as butterflies, dragonflies do not have a pupal stage and transition straight from a larva to an adult. This transition, the final larval moult, takes place out of water. This metamorphosis is triggered by day length and temperature, and is synchronised in some species, such as Emperor Dragonfly.
The final-stage larvae sit in shallow water, near the margins, for several days, getting ready for their final moult and starting to breathe air. Most species leave the water during the morning, but hawkers do so under cover of darkness. Larvae climb up emergent vegetation, although some may walk several metres over dry land before finding somewhere suitable to emerge.
After finding a secure support, they redistribute their body fluids, pushing the thorax, head, legs and wings out of the larval skin.
There is then a pause of about 30 minutes to allow their legs to harden enough for the next stage, when the abdomen is withdrawn. The wings, and then the abdomen, are expanded and start to harden. Muscle action moves water in and out of the rectum. They can even jet around by expelling water rapidly.
They use their legs to crawl around most of the time, but can use jet-propulsion to escape enemies and even to lunge after prey. Watch a dragonfly nymph "jetting" around. Damselfly nymphs swimming. Watch higher resolution versions of these videos on YouTube. Click Here: Nymph Jetting Around!
Click Here: Nymph Swimming! M ost Manitoba dragonflies have only one generation from egg to adult per year. Some require four or more years for one generation. Most have offsetting generations, though, so there are always some adults around each year. S ome dragonflies emerge at night and are ready to fly the next morning. Other species emerge during the day.
Many species emerge in large numbers over a very short period, often just a few hours. They also overwhelm local predators and ensure survival of enough breeding adults. T he synchrony of emergences in most species and the short lifespan of adults mean that each species has its own flight season, the time of year when adults are hunting and mating.
We see dragonflies around from spring to early fall, but it is a series of different species that we see, each with its own flight season of a few weeks.
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