Tag Archives: red-eyed damselfly

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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Fenland safari

Wicken Fen is the largest remaining area of true fen in England and has survived because it has been conserved by encasing it in what is effectively a gigantic plastic bag. The earth on the Fen is waterlogged and if the bag weren’t there the water would simply drain away leaving very rich agricultural soils but none of the wildlife associated with fenland habitats. Another result of the water retention is that the Fen is 6-8 feet above the surrounding farmland and the earth literally shakes if you jump hard on the ground as it’s like a saturated sponge.

Because of the water the predominant habitats are reedbeds and waterways which is reflected in the wildlife. The Fen is so rich in wildlife that a hike around there is like a mini safari! I was there on a hot and sunny Sunday morning in June and wildlife of all sorts abounded. In particular the insects were very busy. This dragonfly had recently emerged from the larval stage as an adult and was sitting in the grass drying out before taking to the air.


Black tailed skimmer youngster preparing for it’s first flights

The young skimmer was on the edge of a path which ran alongside one of the lodes (man made water courses) and on the water opposite the skimmer were lily pads and sitting on one of them was a damselfly, warming itself up in the morning sunshine.


Red eyed damselfly (Erythromma najas) in beautiful repose on a lily pad, surrounded by reflections of the clouds

And of course, that time of year is the season for lurv for many creatures, including this pair of variable damseflies (Coenagrion pulchellum) which are in the process of mating. The male is the blue one and he is clasping the female by gripping the back of her head – the pronotum – whilst she has pressed her genitalia against his abdomen to receive the sperm.

As well the inscect diversity the unique habitat of the Fen is home to lots of beautiful plants and flowers, including this common spotted orchid. This orchid is indeed common and can be found in fens, marshes and other wetlands all over England, but is rare in Scotland. Common, or not, I think all orchids are spectacular flowers and it was really good to see them in such numbers on the Fen.

Common spotted orchid – Dactylorhiza fuchsi

Whilst I was busying myself trying to get photogrpahs of the dragons and orchids a kestrel (Falco tinnunculus, Dansk: tårnfalk) was busy overhead. But even better than that a hobby (Falco subbuteo, Dansk: lærkefalk) was on the hunt for dragonflies and small birds.

The hobby is a small falcon which can be seen in these parts in the summer and hunts low over farmland and reedbeds at phenomenal speed. It’s one of very few predators that can hunt swallows and swifts in flight. This one was doing exactly that and in the distance, a few hundred metres away were at least another two. So I guess it was a family and the chicks had recently fledged and the adults were showing them the ropes. So I whiled away a good half an hour watching their breathtaking aerobatic exploits!


Brimstone butterfly sipping nectar from a thistle flower

I did volutary work at Wicken for 3 years or so back around the turn of the Millenium. It was incredibly rewarding and a good opportunity for a lab-based sedentary person such as myself to get outside and do some donkey work under the sky. One of the projects I worked on back then was scrub clearance to create an area suitable for butterflies to breed. I went and had a look at it on this walk for the first time since I helped to create it and it was very different. The scrub we cleared had been replaced by less scrubby, more proper woodland, trees, and there was small open glades with grasses and wild flowers. Whilst I was in there I flushed a leveret, which is about the closest I’ve ever been to a wild hare, it had been sitting tight but made a run for it when I got just a tad too close – about 5m!

So I didn’t manage a picture of the hare but I did manage a shot of the brimstone butterfly above (Gonepteryx rhamni), which I thought was absolutely lovely, sitting on the purple flower and framed by the two grass stems. It was terribly obliging and let me move all round it to get the best angle for a portrait. So this is about the best shot and one I’m very pleased with. I hope you like it too!

Damsels of Fen Drayton

One of the reasons for my trip to Fen Drayton a few weeks ago was to have a look to see which of our dragonflies were out and about. I went in early June and that time of year is a little early for the true dragons to have emerged, although it’s not impossible. But despite the shortage of the true dragons, the hedgerows and lake sides were abuzz with damselflies.


Male red-eyed damselfly – Erythromma najas

Dragonflies and damselfies are the two members of the taxonomic order ‘Odanata‘ or Odanates. There are two sub-orders within the Odanata: the Anisoptera – the true dragonflies, and Zygoptera – damselflies.

Azure damselfly – Coenagrion puella – the blue form of the immature female

Damselflies in the UK are approximately 4-5cm (1.5-2 inches) long and have thin abdomens and are all smaller and more delicate than the chunkier dragonflies. Having said that, the biggest living Odanate is currently a damselfly who resides in the rainforests of Central America, it has a wingspan of 19cm (7.5 inches) and the abdomen is 10cm (4 inches) long. A real whopper!

Blue tailed damselfly – Ischnura elegans – immature femaleBlue tailed damselfly – immature male – Ischnura elegans

Male and female Odanates, and immature and mature individuals, can often be distinguished by colour. The common blue female below is conspicuously brown so the species gets its name from the electric blue colour of the male. The common blue can easily be confused with the variable damselfly which is the same blue colour, but they are distinguished by the black markings on segment 2 of the abdomen which is shaped like a goblet on the variable and a club on the common blue. Also, the antehumoral stripes (on the side of the thorax) are complete on the common blue and broken on the variable. Although, as the name suggests, the variable is indeed variable and it can make distinguishing the two species a little tricky.


Common blue damselfly female – Enallagma cyathigerum – the only common blue we saw on this trip, perched on my friends finger

The black goblet on segment 2 is visible under the front of the wings on the variable damselfly below. But confusingly, it’s living up to its name because the antehumoral stripes are unbroken.

Male damselflies have two sets of paired claspers at the end of the abdomen which it uses to clasp the female on her pronotum, which is the protrusion in the middle of the back of the head. The claspers have tiny hooks on them which match grooves in the female pronotum and in order to avoid procreational mismatches the hooks and grooves are species specific.

Variable damselfly – Coenagrion pulchellum

In the picture above a variable male has clasped his lady by the pronotum. Male damselflies have primary genitalia at the end of the abdomen on the 8th segment, but in order for fertilisation to take place he needs to transfer a ‘spermatophore’ from the primary genitalia to the secondary genitalia on the second segment at the thoracic end of the abdomen. The female then curls round in to the ‘wheel’ position to transfer the sperm to her genitalia which are underneath her 8th abdominal segment.

A pair of variable damsels in the wheel position

All the Odanates are carnivores, and the larvae which hatch from eggs layed under water are ferocious carnivores, the larger ones will even take small fish! On one occasion last year while I was photographing large red damselflies (Pyrrhosoma  nymphula), a large hawker dragonfly (I think it was a migrant hawker, Aeshna mixta) which had been buzzing around higher up for several minutes suddenly dived down and caught one of my large red damsels. In a few seconds the migrant butchered it and ate it on the wing and the inedible bits of wing and leg were discarded and rained down around me.

Scarce chaser – an immature male

A lone Anisopteran, or ‘true’ dragon was spotted on this trip and it was an immature scarce chaser, Libellula fulva. He was a lovely mustard colour and he can be differentiated from the female by the colour of the thorax which is dark grey in the female, and from the male adult who is electric blue. He undergoes quite a transformation in transitioning from immature to adult.