The Dragonfly - Life-cycle and habitat
I love photographing insects, the diversity and colour found in the insect kingdom is amazing and provides an endless source of interesting subjects to photograph. I took the photograph of a dragonfly below on the river walk in Villajoyosa.
A Pair of Dragonflies Mating
I posted the above photographs on another site and in one of the comments someone said
‘I don't think I have ever seen a "baby" dragonfly!
It was then that I realised that I knew little or nothing about Dragonflies except that they looked pretty with their bright colours. So I set out to find something out about these wonderful little creatures.
The River Amadorio is actually little more than a small slow moving stream but the area is teeming with all sorts of wildlife including dragonflies.
Female dragonflies need a source of fresh water in which to lay their eggs. This is why the river walk in Villajoyosa turned out to be such a good place to find dragonflies.
The River Amadorio
As you can see from this hub dragonflies are found near water. This is because a female dragonfly needs freshwater in which to lay her eggs'
A female dragonfly will typically lay between one hundred and a thousand eggs in an episode depending on the species.
I found this video of a female dragonfly laying her eggs in water it is well worth watching the process as the video is of extremely good quality and the commentary is very informative. To watch the video please click on the youtube logo on the bottom righthand corner of the video and it will take you right to the video on youtube.
A Female Dragonfly Lays Her Eggs
Once the eggs hatch out the dragonfly nymph begins its long journey towards adulthood. The dragonfly nymph undergoes several stages as a nymph and this process can last anything from about six months to five years depending on the species. Most of a dragonfly’s life is spent as a nymph under water.
Normally the nymph does not chase its prey instead it lays in hiding waiting for its prey to come within reach. The nymph is a squat looking dingy brown insect with six walking legs and like the adult it is to grow into it is very much a carnivore and a predator. It catches its prey by shooting out its hinged bottom lip, which has on it a set of powerful pinchers.
These pinchers located at the outer edge of the lips grasp hold of its prey and after eating the bottom lip is retracted back forming like a mask over the lower half of the nymphs face. Like the adult form it will eat just about anything it can catch its menu typically includes mosquito larvae, tadpoles, small fish, water bugs and even other dragonfly nymphs. They can devour their own body weight in one sitting they are voracious eaters.
The Nymph Moults
As the nymph grows it moults on its final moult which can be as long as five years after the egg was laid it crawls out of the water and attaches itself to something solid like a twig. In this final moult the outer skin dries and the body begins to swell forcing the skin to begin to split somewhere on its back. After a struggle the adult dragonfly begins to emerge from the husk of the nymph.
Once free of the husk it begins to pump blood into its wings inflating them to their full size during this stage the adult dragonfly is extremely vulnerable to predators as it can do nothing to escape them. It takes time for the sun to dry and harden the dragonfly’s body and wings but once this is accomplished the adult dragonfly is ready to eat and mate.
Thirty Beats a Second
After all this hard work the dragonfly usually only spends about two months as an adult dragonfly. Most dragonflies do not die of old age they mostly end up as prey themselves before they die of natural causes.
The chief predators of dragonflies are birds who pick them off much like the dragonflies do their prey by plucking them right out of the air. Fortunately not before most of them have time to mate.
There are about five thousand different species of dragonfly and of these roughly four hundred and fifty are found in America. The dragonfly belongs to order of insects known as the Odonata and this order is split into two categories Anisoptera, which are the Dragonflies and Zygoptera, which are the Damselflies.
The dragonfly has six legs and four wings that beat at around thirty beats per second and their wings do not have to beat in unison. What does this mean? It means that they are very efficient fliers with extremely good manoeuvrability.
Compare the thirty beats a second that the dragon fly needs to remain airborne to some of it prey.
The fly for instance requires about a thousand beats of its wings per minute to keep it flying and the mosquito needs to flap its wings around six hundred times a minute. From this you can see that the prey of the dragonfly has to expend considerably more energy in order to stay in the air.
The dragonfly is amazing when flying it can hover, fly backwards, sideways and even loop the loop and is capable of changing its speed and direction in an instant. They are not only very agile in the air they are also very fast an Australian Dragonfly was recorded doing speeds of around thirty six miles per hour.
The dragonfly has a compound eye that is made up by thirty thousand lenses (ommatidia) with those in the upper part of the eye looking forward being larger and more numerous. The shape of its eye enables it to see almost three hundred and sixty degrees and this makes it very easy for the dragonfly to detect the movement of its prey but it doesn’t see details very clearly.
The dragonfly can just about catch anything it sets its sight on, which is good news for us as its prey is often what we would consider pests. Mosquitoes, flies, and gnats are just a few of the pests that the dragonfly helps to keep in check.
Both as an adult dragonfly and as a nymph this creature is a killing and eating machine whose prey is mainly other insects it is a very beneficial regulator of the insect population.
The Dragonfly has Compound Eyes
The Dragonfly Can Eat its Own Weight in Half an Hour
The dragonfly is an impressive carnivore hunter who can eat its own body weight in just thirty minutes. When you consider the size of mosquitoes for example that is a lot of mosquitoes in a very short period of time. Just to put this in perspective this would be equivalent to you or I eating around a hundred and thirty five pounds of food in half an hour.
Normally the dragonfly will snatch its prey right out of the air using its legs to form like a basket to scoop up its prey. It does this with consummate ease as it can out fly and out manoeuvre just about all of its prey. It eats its prey while it is still in the air by ripping pieces off its captured prey chewing it. The dragonfly will eat around six hundred insects a day.
Usually the dragonfly hunts alone but dragonflies are known sometimes to hunt and feed in swarms. This happens when there is an abundance of insects such as when termites or ants swarm.
See the video below for Dragonflies swarming in a back garden of someones home. I found this video on YouTub so it is not my back garden nor is the delighful child who dances in this video my daughter, but she is a real cutie.
The Dragonfly Swarm
The dragonfly uses its legs to catch its prey and to cling to objects such as twigs and grasses while resting its legs are useless when it comes to walking.
People need not fear the dragonfly because it will not bite or sting and the only thing it might show is curiosity when it comes to people.
Well I hope that you have enjoyed finding out a little about this wonderful creature called the dragonfly.
If you have enjoyed this Hub then you most certainly would love a sister hub to this written by Peggy W. Peggy writes in a way that is so easy to read and she draws you right into her experience.
A big thank you to those of you who got this far on this hub, I hope you enjoyed the photographs.
On Peggy's Dragonfly Hub are some excellent photographs that she has taken of the Dragonfly that visited her back garden. Do yourself a real favour and pop over to her hub and see the delightful photographs she has taken and read some of the interesting facts she has found out about dragonflies, I learned some things there that I didn't know. Here is the link to Peggy's Dragonfly Hub
Finally, I will finish off this hub by including a few more photographs that I took of the dragonflies on the river walk in Villajoyosa.
From the amount of mating going on in the photographs above, we should not be short of Dragonflies next season, at least I hope not as I love to photograph these striking looking insects, and I hope that you have enjoyed the photographs I have included in this hub.