Dragonfly Emergence - the early stages

Look out for emerging dragonflies and damselflies when enjoying spring and summer walks close to water, and you may be rewarded by a sight that is one of the wonders of nature.

After spending their early life phases underwater, body condition and weather trigger in dragonfly and damselfly larvae the desire, or more probably then instinct, to emerge from their watery home, climb a stem of aquatic vegetation, break free of their larval case and take to the air as the winged adults that brighten the New Forest landscape with dashing, multi-coloured bodies and acrobatic flying displays.

Some, particularly those seen in spring, synchronise emergence, whilst others spread the event over a longer period.

Sadly, though, many would-be insects do not complete the process, as at this time they’re susceptible to predation by a range of birds, often with hungry chicks to feed, and are also at the mercy of wind and rain. But thankfully, many are successful.
 
For the larger species, transformation takes 3-4 hours, whilst for smaller insects, somewhat less. The whole process is split into a number of distinct phases, each followed by a gap whilst the emerging insect rests, gathers its strength and prepares to move on to the next step.

Here's the early part of the process:

The larva climbs up a stem that will be used as support, the legs take a firm grip on the stem, and breathing becomes adapted to the open air, rather than underwater. A split appears in the back of the thorax of the larval case.

The thorax of the emerging adult pushes through.

References:
A Guide to the Dragonflies of Great Britain: Dan Powell
Dragonflies and Damselflies of Britain and Northern Europe: Bob Gibbons