Tag Archives: damselflies

Fenland safari

Posted on September 8, 2012 | 21 comments

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!

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Posted in Anisoptera, Birds, Birds of prey, Countryside walks, Falcons, Flora and fungi, Insects, Ornithology, Skimmers, UK wildlife, Wicken Fen, Wild flowers

Tagged black tailed skimmer, brimstone, butterfly, Coenagrion pulchellum, common spotted orchid, Dactylorhiza fuchsi, damselflies, dragonflies, Erythromma najas, Falco subbuteo, falco tinnunculus, fen, flora and fauna, Gonepteryx rhamni, hobby, kestrel, lærkefalk, lily pads, marsh, Nature, Odanata, Odanates, red-eyed damselfly, reedbeds, tårnfalk, variable damselfly, Wicken Fen, wildlife, wildlife safari

Damsels of Fen Drayton

Posted on June 24, 2012 | 29 comments

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.

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Posted in Anisoptera, Chaser dragonflies, Countryside walks, Damselflies, Dragonflies, Fen Drayton, Fen Drayton nature reserve, Hawker dragonflies, Insects, RSPB reserves, UK wildlife, Zygoptera

Tagged Aeshna mixta, Anisoptera, azure damselfly, blue tailed damselfly, Coenagrion puella, common blue damselfly, damselflies, damselfly mating, dragonflies, Enallagma cyathigerum, Erythromma najas, Fen Drayton, insects, Ischnura elegans, large red damselfly, Libellula fulva, Migrant hawker, Nature, Odanata, Odanates, Pyrrhosoma nymphula, red-eyed damselfly, RSPB, scarce chaser, true dragons, wheel position, wildlife, Zygoptera

Dragon hunt

Posted on May 23, 2011 | 3 comments

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.