Tag Archives: Zygoptera

Home grown dragons

One end of my front garden is curved and tapers to a point and was pretty much dead space, so last year I decided that I’d turn it into my own tiny nature reserve and make a pond. The street side of the garden is lined with beech hedge and the open end is bound by a hazel tree which I planted there 5 or 6 years ago, so it is an enclosed space which I hope will remain fairly undisturbed, apart from my forays to photograph the wildlife that takes up residence.

In order to try to maximise the wildlife potential I followed all the instructions on how to create a wildlife pond, so it’s around 30cm deep (which is enough to prevent the bottom from freezing even during the coldest UK winter) and was seeded with plant life and minibeasts from my friends pond, and there are no non-native species and no fish. The water went into it in February this year from my water butt (tap water contains chemicals which are not good for a balanced wildlife pond) and it’s remarkable how rapidly nature has taken hold. As well as all the beasts added by me which seeming to be flourishing, it has been discovered by various species of dragonfly, butterfly and hoverfly, and I put twenty common frog tadpoles in from another friend’s pond, of which at least one reached adulthood.

Common darter female (Sympetrum striolatum) perched on an iris leaf

In the corner of the garden where the pond is I’ve let the grass and wild flowers grow and I mow a path all the way round, so I can view it from all angles, and in one corner a small patch of stinging nettles is allowed to grow unhindered. In this way I’m hoping that eventually the grassy area will reach a balance with local wild flowers and provide a suitable habitat for a few more insect species. As well as the ubiquitous white butterflies, peacocks, and other regular garden butterflies visiting the garden, since the completion of the pond I’ve also added gatekeeper and speckled wood to my garden species list.

Common darter male drawing breath after a hard days mating

Apart from the introduced tadpoles, the most interesting visitors to my little zoo have been the dragons, of which I’ve seen at least 3 species of damsel, one darter and one hawker species, all either settled around the pond or hunting over it. Of these, the most notable have been the common darter which are very common in my part of the world, and are often very easy to photograph, and consequently the most frequent species shown here in my posts. But I think they’re incredibly photogenic! And this year in the garden I’ve managed to capture several aspects of their reproductive life cycle.

Common darter tandem pair

This pair, in the midst of copulation, were being constantly harassed by a lone male which had taken up defensive positions on the pond and was defending it vigorously. But they were not to be deterred and completed copulation and began ovipositing in the pond despite the unwanted attentions of the loner.

The male common darter has primary and secondary genitalia, the primary genitalia, located on the last abdominal segment, produce the sperm which he transfers to the secondary genitalia on abdominal segment 2 (counting along from the thorax), which contains the penis with which he inseminates the female. Transfer of sperm is done prior to clasping a mate with the anal appendages or ‘claspers’ at the ‘pronotum‘ (a plate of the exoskeleton at the back of her head) in the case of damselfies (Zygoptera), or by the head in the case of the Anisopteran dragons. She then attaches her genitalia to the sperm-containing secondary genitalia of the male and fertilisation ensues.

The tandem pair, now fertilised, looking for places to oviposit

Once the female had been fertilised, they flew around the pond and when they had identified a suitable location the female swung her abdomen downwards to eject an egg into the water. Some species of dragonfly search for specific locations underwater, such as the underside of leaves or within the stems of water plants, to lay their eggs, but the common darters were placing them directly into the water. Consequently they darted swiftly to and fro over the pond and the ovipositing movement was extremely rapid, making photographing the event a challenging task, but I managed one half decent shot:

The next chapter in this story will be when the eggs hatch to release the larvae into the pond, which happens 2-5 weeks after laying the eggs. Dragonfly larvae are voracious predators but there should be sufficient other insect life in the pond to keep them sated, and if I can catch one I’ll post the pictures later. And hopefully I can pphotograph one as it emerges from the water and metamorphoses into the adult dragon, which should happen next year if they survive.

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The disappearing dove

Every year millions of migrating songbirds heading from Africa to Europe get blown out of the sky by weird people with shotguns. That combined with the policy in the UK of destroying habitat at an alarming rate is making life impossibly possibly difficult for some of our iconic bird species, one of which is the turtle dove (Streptopelia turtur, Dansk: turteldue).

But last summer I was exploring one of my regular haunts, Milton Country Park, on the northern edge of Cambridge, on a warm Saturday morning and the air was buzzing with insects including this handome hoverfly known as the ‘footballer‘ due to its rather fetching black and yellow striped thorax. This species is common in England reaching a peak in July which is when I snapped this individual.

The footballer hoverfly – Helophilus pendulus

And hoverflies aren’t the only abundant insects to be found in July. Milton Country Park is also home to mumerous species of Odonata, the dragonflies (Anisoptera) and damselflies (Zygoptera).

Common blue damselfly – Enallagma cyathigerum – perched on a seedhead

The Park has 4 big lakes:

MCP map

…and a few other streams and pools, and despite the abundant human presence it remains a haven for some properly exotic wildlife including a bittern that appeared for a week or so last year, and the occasional osprey stopping off on migration from sub-Saharan Africa to breeding sites further north in the UK.

The great crested grebe (Podiceps cristatus, Dansk: toppet lappedykker) isn’t an exotic migrant but it’s a beautiful bird and can always be found here:

The grebe was almost hunted to extinction because its dense feathers were coveted as a substitute for fur. But it has recovered and can now be found on lakes over most of the UK. The one above is an adult and the one below still has the striped head markings of a juvenile.


But getting back to the point, the undoubted star of the show on this trip was the turtle dove:

The turtle dove is in very serious decline, I believe we have lost around 97% of our breeding population and it is anticipated it will become extinct in the UK by 2020 as it’s also under increasing pressure in Europe. The reason for its catastrophic decline is that it feeds on seeds from cereals and other plants and both of these are a scarce commodity in the fields of the UK at the time the doves need them.

So the birds arrive here in the UK exhausted after a heroic migration across the Sahara and the Mediterranean. And those that avoid the gun-toting imbeciles in southern Europe arrive here to find there’s not enough food. So as it takes them a long time to rest and feed and get back into breeding condition, they only have time for a maximum of one brood per season before they have to head all the way back. And this enforced curtailment of there breeding window means they just can’t sustain their numbers.

They arrive back in the UK from around mid April so I’ll try to capture some more photographs before they finally stop coming here all together.

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.

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.