The Emperor Dragonfly, which is one of the largest species of hawker dragonfly in Europe and is my favourite dragonfly, many hours spent watching these powerful flyers flying around my local quarry and lakes in the New Forest, Hampshire.
Both sexes which are similarly marked have an apple green thorax and a sky blue abdomen with a central dark stripe, female has a greener blue abdomen. Watching these dragonflies in the wild, they are very territorial, especially the males chasing it each other high into the sky with amazing speed and agility. They mostly catch and eat their prey on the wing. Dragonflies can be found on the wing from June to late August. A lot of patients is needed when filming these beautiful dragonflies especially the males.

Dragonfly Nymph
As a young boy with friends we would go searching for dragonfly nymphs, using my dads landing net, and often getting into trouble, returning home with boots filled with water, other dragonflies where always found but this species was are favourite. We would keep the captured nymphs in fish tanks, and it was fascinating watching them feeding on worms and other insects.  The nymphs would live ok together, if similar size. When we could see the adult dragonfly developing inside the nymph we would place long sticks into the tank, and place a netted cage over the top, for the adult nymphs to climb so the dragonflies could emerge and dry there expanded wings Later we would release the large dragonflies back into the wild. Carrying them back to a local lake in black boxes so they did not fly and damage their wings.
The nymphs are a fearsome predator, feeding on small frogs, tadpoles, newt’s even fish. The nymphs which grow to a large size have an extendable labium, which at rest is in a folding position underneath the head. In layman terms its just a folding arm which thrust forward very fast to capture and hold its prey, it is equipped with a sharp jaw with sharp bristles, to insure its prey is secure while eating it.
No risk of being bitten buy a nymph but I do remember they have 3 prongs at the back of there abdomen which they can turn and dig in to your hand, which they probably use as a defence. A dragonfly nymph can take up to 3 years to develop shedding its skin up to 15 times.