Tag Archives: emperor dragonfly

Dragonfly drama

Early last Saturday morning I set off for Paxton Pits, a group of lakes on the edge of St Neots, between Bedford and Cambridge. It was anticapted that we wouldn’t see much birdlife but there could be some inteersting dragonfly activity. And apart from a lone turtle dove (which justifies the trip on its own!) and a sparrowhawk, we noticed surprisingly few birds. But the Odanata were there in abundance with large numbers of various species of damsels and true dragons.


Common blue damselfly

I spotted this common blue (Enallagma cyathigerum) before I’d even got out the car. This one a male, was perched on a seed head at the edge of the carpark and there were several others in the vicinity warming themselves up in the early morning sunshine. At the other side of the carpark is the visitor centre which has a small pond outside and over the pond were a red eyed damsel (Erythromma najas) and another common blue warming up on the same rush leaf:

Paxton Pits are disused gravel workings and have been turned into a nature reserve that is managed by Huntingdonshire District Council with the back up of the voluteers of the ‘Friends of Paxton Pits’. If you happen to be contemplating a visit to the Pits, there is a lot of information on their website: (https://sites.google.com/site/paxtonpitsnaturereserve/home), and the reserve also has a blog where sightings at the lakes can be recorded: (http://paxtonpits.blogspot.co.uk/). The website lists all the Odanata that have been resident there and many of them were on display on Saturday. They don’t all emerge at the same time of year so it would never be possible to see all of them during one visit.


Another common blue damsel on final approach to land on a stinging nettle stem

The Pits are adjacent to the River Great Ouse and swarms (literally!) of banded demoiselles (Calopteryx splendens) were fluttering within 20m or so of the banks of the river. The banded demoiselle is one of two species of demoiselle in the UK and the only one in the east of England, and I think they’re absolutely beautiful as they sparkle in direct sunlight:

A female banded demoiselle perched on top of a nettle (I like the background here – out of focus brambles)

The other species of UK demoiselle is called the ‘beautiful demoiselle’ (Calopteryx virgo) and is found in the south and west but not the east. It is most easily distinguished from the banded version because the wing pigmentation in the male extends to the base of the wing, so it’s a much bigger spot than those on the wings of these banded demoiselles:

Above and below: male banded demoiselles

And the female beautiful demoiselle  has broader wings with a brown tint that’s lacking in the banded demoiselle. The male demoiselles were busy chasing females with all thoughts turned to mating.

But in the midst of all the the mating activity, danger, as always, was lurking in the undergrowth. This unfortunate female common blue damsel had been caught in  a spider web and was in the midst of a mortal struggle with the owner, which she eventually lost:

The male common blue was also caught in the web and was struggling to extricate himself. Fortunately for him, all the spiders efforts were needed to subdue the female and whilst it was otherwise distracted he made his escape whilst the female eventually succumbed to the spider venom.

A dragonfly larva having scaled a stem to leave the water will shortly burst out of its skin and fly off as an adult dragon

It’s also that time of year when dragonfly larvae are metamorphosing into adults. The larval stage of all dragonflies is aquatic and so they require gills or ‘caudal lamellae‘ to breath underwater, and these can be seen protruding from the end of the abdomen of the larva above. At the end of its aquatic life the larva climbs a stem out of the water and emerges from its larval skin as an adult, leaving behind its discarded outer casing, or ‘exuvia‘:

Dragonfly exuvia  – a dried out larval husk left behind on a rush stem after the new adult has flown

As well as the damsels, several species of true dragons were on the wing including brown hawker, migrant hawker, black tailed skimmer, and the grandaddy of all UK dragons, the emperor (Anax imperator):

Emperor dragonfly male patrolling his stretch of water against allcomers

The emperor, as its name suggests, is a whopper. It is also an aggressive defender of its territory, a consummate aeronaut and a ferocious hunter, taking prey as big as other dragonflies. It’s easily distinguished from other dragons by its sheer bulk, the apple green thorax and the drooping abdomen. I sat and watched this one for some time and he rewarded my patience by posing for a portrait on a stem just  a few metres away:

And after all the dragon activity I peered into the water on the way home and spotted this little chap:

A young newt

I don’t know what species of newt this is but it’s still so young it hasn’t adapted to air breathing and still has its feathery gills which are visible just in front of the fore legs.

It’s been a long time since I last posted so it’s good to be back Life should be generally less busy for the back end of the year and I’ve got lots to share, so hopefully I can start to post more regularly again!

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Dragon hunt

Not the fire-breathing type but Anisoptera. I spotted the first dragon this year over Easter during a picnic at Grantchester Meadows, south of Cambridge. It wasn’t, technically speaking a dragonfly, but a damselfly, specifically, a large red damselfly (Pyrrhosoma nymphula), which is one of the first to emerge after the Winter. Due to the weather this year many things have happened earlier than usual and the large red was out and about in late April. And they are magnificently red:


Large red damselfly male. There are three colour forms of the female all of which have more dark banding on the abdomen than the male

Milton Country Park on the northern edge of Cambridge is a great place to see numerous species of dragonfly and damselfly, and on a foray there on Saturday with my friend, David, we counted 10 species. Dragonflies – I’m using this generic term interchangeably to cover dragonflies (Anisoptera) and damselflies (Zygoptera) – are remarkable creatures, there are few more accomplished aeronauts in the animal kingdom, and the various life cycles are amazing.

The life cycles involve an aqautic larval stage, the larvae hatching from eggs laid either underwater or inside plant material close to the waters surface. The duration of the larval stage is affected by various factors including temperature, and for species such as the blue tailed damselfly (Ischnura elegans), this results in the difference in duration of the larval stadium (developmental stage) of 1 year in warmer parts and 2 years where it’s colder.


Blue tailed damselfly, immature male

After the larval stage, metamorphosis, switched on by warmer temperatures and extended day length, occurs over a few weeks and concludes with the emergence of the adult from the larval cuticle when it will dry out and take to the air. The drying out process is hazardous as it renders the new adults susceptible to predation by birds, consequently they time their emergence to occur at night or in the early morning. New adult dragonflies then disperse from water for approximately a few days to a few weeks, until they are sexually mature, when they return to the water for the serious business of finding a mate and starting the whole process over again.

This is a very incomplete and generic description of the dragonfly lifecycle, but if you want to discover more I recommend a book called ‘Field guide to the dragonflies and damselflies of Great Britain and Ireland’ written by Steve Brooks and illustrated by Richard Lewington (ISBN 978 0 9531399 0 3). It’s a very well written book with lots of easy to read information and high quality illustrations. And because there are only around 40 or so species of dragon and damselfy in GB and Ireland it won’t take you all year to read!

On our walk we saw hairy and emperor dragonflies (Brachytron pratense and Anax imperator respectively), both species of hawker, which I couldn’t get good photographs of as they were whizzing around over the water at high speed and never seemed to settle within range. Similarly with the four-spotted chaser (Libellula quadrimaculata), but then as we positioned ourselves in a very good viewing location on one of the smaller lakes a scarce chaser (Libellula fulva) appeared on a nearby seedhead and with occasional forays stayed there all the time we were there, giving some great photo opportunities:


Scarce chaser male, the female has a yellow abdomen with a thin black spine and doesn’t have the three black end segments

There were lots of damselflies too, apart from the large red and blue tailed already mentioned. Variable damselfly (Coenagrion pulchellum):

Azure damselfly (Coenagrion puella):

And common blue damselfly (Enallagma cyathigerum)

This pair of common blues are in ‘tandem’ with the green eyed female underneath. This position is adopted by non-territorial damselflies where the male grips the female behind the head and in this way ensures that no other male can mate with her before his eggs have been laid – a process called ‘ovipositing’. The eggs hatch out after 2-5 weeks and the larvae begin their development underwater where they are ambush predators, feeding on a variety of prey from other insect larvae to tadpoles and even small fish!

They are amazing creatures, and more species will be emerging over the next weeks and month so hopefully I can gather some more images of other species for subsequent posts before the Summer ends.