Tag Archives: scarce chaser

Lunchtime nature walk

Several years ago I took a lunchtime walk around the lakes on the Science Park in Cambridge and the banks of one of the lakes to a depth of 5-10m was absolutely jumping with froglets. These little guys must have just emerged from the shallows en masse, there were literally 10’s of thousands of them and when I stood still it looked as though the grass was moving. It was an amazing sight.

I took another walk around the same lake this summer and the frogs were there again, not in anything like the numbers the first time I saw them, but big numbers nonetheless. They were the young of the common frog, Rana temporaria. Fortunately, this time I had a camera with me and I managed to get a picture of this little chap. As you can see, he was tiny, smaller than a clover leaf which was approximately 1cm across.


A tiny froglet seeking cover under a clover leaf


Scarce chaser in flight, reflected in the lake

The timing of my foray was just as the rains were subsiding and several species of darter, hawker and chaser dragonflies were busy hunting over the lakes, including this adult male scarce chaser, Libellula fulva. I’ve decided to try to photograph dragonflies in the act of doing soemthing other than sitting still and this the first shot I have of one flying. Not brilliant, but OK for a first attempt!

Because the Science Park is all neatly kempt and the grass cut regularly it’s not the best place to see wild flowers. So it was a pleasant surprise to see an orchid lurking in the undergrowth close to the lake where the blades of the grass cutters can’t reach.

Common spotted orchid – Dactylorhiza fuchsii

I think of all orchids as being terribly exotic, but this little beauty is relatively common, as its name suggests. It’s found over nearly all of the UK and thrives on a wide range of habitats including marshy wetland, chalk downland and also colonises wasteland. It’s a favourite food source for day flying moths and gets its name from the purple spotted leaves which are clearly visible on this flower.

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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.

2011 – That was the year that was

Every month of the year has different conditions which create environmental niches that favour different flora, fauna and stages of life cycles. So as 2011 rushes headlong to its wintry conclusion, for my last post of the year I was going to select a single photograph to represent the month to month changes in our wildlife throughout the year. And that was of course impossible for a number of reasons, mainly because it was impossible to represent any one month with a single image, and also because I have lots of images that I like and I want to share. I eventually managed to whittle the number down to an average of two per month which include a wide range of our native creatures in the UK including birds (migrants and natives), butterflies, moths, flowers, amphibians and fungi. I hope you like them!

January

Every autumn  lots of bird species vacate our shores to head to warmer parts of the world while we endure the cold of winter, and they’re replaced by other species which come from the north to the relative warmth of the UK in winter. Last year the autumn and winter weather in Scandinavia was ferocious and consequently many birds arrived here in larger numbers than usual, including the gorgeous waxwing. Along with the waxwing, redwing and fieldfare came too, as they do every year, and remained until the spring, providing some welcome colour.

On a bright cold January day a lone fieldfare perched in a tree

February

February was cold and the middle of the month saw us taking the children to the coast for our annual spring half term excursion, and this year we headed to the Suffolk coast at Dunwich. Dunwich is a really interesting place for lots of reasons, not least because the wildlife there is rich and varied. One of the harbingers of springtime which I look forward to every year is the flowering of snowdrops, and the woods on the edge of Dunwich were covered in them:


A carpet of snowdrops in the woods at Dunwich Greyfriars

March

By March many flowers were blooming and the fauna was turning it’s thoughts to matters procreational. And this dunnock was no exception:


A dunnock serenading the ladies from a bramble stem on Cambridge Science Park

Dunnocks have a rather to-the-point approach to the art of regeneration. They don’t get together in pairs as most birds do, they form small groups and mate with multiple partners and the males go as far as to remove packets of sperm from the cloaca of females who have been inseminated by rivals prior to passing on their own DNA. No nonsense!


A robin singing for a mate in an alder tree, also on Cambridge Science Park

And of course the birds aren’t the only creatures to get the urge in March. For the past 2-3 years a guided busway has been built between St Ives and Cambridge and as it approaches Cambridge Science Park it passes alongside a lake that is a spawning ground for thousands of toads which live in the adjacent woods and fields. The busway has therefore cut off the toads from the lake and, driven by the unstoppable instinct to reproduce, this pair were trying unsuccessfully to negotiate the sheer walls of the track. For a week in March I would get off my bike every morning on the way to work to help as many of them across as I could find.


The male toad is hitching a lift on the back of the much larger female on the way to the water to spawn

The male toad locks onto the back of the female with his front claws around her chest and he’s not at all keen to relinquish his grip until they’ve reached the water and he’s fertilised her eggs. After which armies of lone toads can be seen heading back the other way.

Fortunately for the toads Cambridge City Council funded the installation of toad tunnels under the busway so next year they should be able to negotitate the track and avoid the carnage which would otherwise have ensued. Hats off to the Council!

April

This month was a real wildlife fest and many types of creature allowed me to take some great photographs. The trees now have shooting leaves so everywhere has that lovely green colour from all the fresh growth.


Windswept male yellowhammer in the top of a hawthorn tree

The yellowhammer is a species which has become less and less common in recent decades as a result of hedgerow destruction and other modern farming methods, but we’re lucky to have plenty of hedgerows still in situ on the outskirts of Histon, and consequently, good numbers of these lovely yellow buntings. The hedgerow this one is on is mature and has old oak and ash trees in so it plays host to alot of bird species including blackcap, chiffchaff, dunnock, common whitethroat and green woodpecker, to name but a few.

Whilst sitting watching TV late one evening in March, what I initially thought was a bat emerged from behind the sofa I was sitting on with my wife. There had been no prior warning of its presence and myself and my wife both levitated off the sofa uttering something along the lines of “What the heck was that!?”. It fluttered into a lampshade where it staid long enough to get a photograph, and it turned out to be an emperor moth:


Our emperor moth inside a lamp. I though creatures like that only lived in tropical rainforests!

Unfortunately, a couple of days later I found her dead (she was the female of the species) still inside the lampshade. I extricated her and measured her and she was 7cm wingtip to wingtip. A magnificent beast.


A willow warbler beautifully framed by new leaves and blossom of the blackthorn tree

These little warblers which weigh on average around 9g have just arrived from southern Africa. I think bird migration is one of the most amazing natural phemonena – how does such a tiny creature navigate and survive a flight across the Sahara and then the Mediterranean? It’s absolutely incredible.


A pair of great crested newts getting ready to mate in a shallow pond – male on the left, more slender female to the right

The great crested newt was probably the highlight of my year. I’d never seen a newt before and in this pond there were great crested, palmate and smooth newts. I turned the flash power down and used an 18-55mm lens and got some reasonably good photographs of the newts underwater. And that at 1am after a few hours in the pub!

May

I’ve spent many a fruitless hour chasing orange spot butterflies up and down the hedgerows of Cambridgeshire, but they never seemed to settle for long enough to get a photograph. But one morning in May I must have timed it just right, they were in the mating mood.


Female orange spot announcing her availability in somewhat unambiguous fashion to a passing male who was just out of shot


Common whitethroat – these warblers also migrate to the UK from sub-Saharan Africa

The common whitethroat breeds in my local fields in good numbers. It’s easy to identify by its song and the way it perches on brambles and low scrub and then flits almost vertically up into the air to alight a few seconds later close to where it took off from and continue singing. This one is a male, he has a blue/grey head whereas the female has a brown head. As well as avian migrants from warmer climes, at this time of year many species of dragonfly are emerging:


Scarce chaser dragonfly at Milton Country Park

I like dragonflies. In the days of the dinosaurs there were dragonflies with a 75cm wingspan! They are fun to photograph (and often, not too difficult) they look awesome, and they have very interesting life cycles. My scarce chaser sat on a seed head for several minutes whilst I stood a few feet away photographing other dragons and damsels, occassionally he took off to circle the pond before returning to the same spot where he let me get to within around 50cm to capture his portrait.

June

In a normal year the weather will be warming up  nicely by June and flowers and insects and birds should be in abundance. But 2011 wasn’t a normal year, April was unseasonally warm which kick started everything, but the rest of spring and summer were cold and this had dire consequences for many butterflies and other species. One of the few that I did see in reasonable  numbers this year, although not as many as last year, was the large skipper.


Large skipper feasting on the nectar of a thistle

The marsh woundwort is so called because it has been applied to wounds to assist the healing process. I don’t know what the medical basis for that is, maybe it has antispetic properties. It  has a beautiful flowerhead and is one a good number of wild flowers growing in the drainage dikes on the local farmland around Cambridge.

Marsh woundwort poking it’s lovely head out of a drainage ditch which is full of various wild flowers every year

July

I found this splendid looking cricket lurking in the grass in a field on the edge of Histon. I first thought it was a very green grasshopper until I looked more closely at the photograph, and it turned out to be a Roesels bush cricket. It is an introduced species from mainland Europe which until recently was only found in the most southerly parts of England. There are two varieties and this is the long winged one which can colonise further afield faster than its short winged cousin, and is now as far north as Cambridgeshire and beyond.


Long winged Roesels bush cricket

This was the first of its kind that I’d seen and a few days later another one appeared on a blind in my house, so I guess thay can’t be that uncommon in this region now.

A pair of juvenile linnets

Before I got out walking in my local countryside around Histon I can’t remember the last time I saw a linnet, but they breed here in good numbers and in the winter flocks of many tens to hundreds can be seen on farmland around and about Histon. Linnet are finches which feed on seeds and the adult males are splendid with a cerise breast and a crimson spot on their foreheads.

August

When I was at school, many years ago, my Dad would feed the birds in the garden and it wasn’t particularly unusual to see the occasional bullfinch.  But mainly as a result of persecution their numbers declined dramatically through the 1970’s and 80’s and I didn’t see one for years. The males are beautiful birds and I’ve been after a good photograph of one for a long time. And finally…


A male bullfinch crunching seeds at RSPB Fen Drayton

I love this picture – so far it’s the first and only half decent one I’ve managed. Hopefully I’ll get a few more to share with you in 2012.

Later in August, we were on holiday in Northumberland, and amongst the many gulls and other seabirds on the beach at Seahouses was this redshank. I think it’s nature at it’s aesthetic best!


A lone redshank looking for nourishment in the rockpools at Seahouses

September

The biggest garden spider I’ve ever seen – she was around 4cm across

Another of natures harbingers, this time of autumn. My garden fills up with these polyocular purveyors of terror in September, and this lady was huge. She was 4cm across and was big enough to distract my son from a telling off. ‘Dad, there’s a big spider in my window‘ was an imaginative and very effective way to divert my attention from the misdemeanour of the moment. I ran to get my camera and I had to lay horizontally out of the bedroom window to take this photograph, as a result of which I couldn’t stay still for more than a few seconds!

October

After the coldest summer for 18 years we then had a mild autumn which meant that many creatures could be found out and about long after they have normally  migrated or hibernated, or died off. Swallows and swifts were still being seen into October and a bumblebee flew past my lab window one day last week. During a visit to Milton Country Park, on the northern edge of Cambridge, on 28th October, to see what winter wildfowl had arrived, there were some winter visitors including tufted duck, gadwall and widgeon. But the pontoon I was stood on had around half a dozen common darter dragonflies on it along with several species of damselfly in the surrounding reedbed and a lone migrant hawker patrolling the air which took a common darter and butchered it on the wing right over my head. Dragonflies can be seen late in the year when the weather permits, but even so I was surprised to see so many at the end of October.

A pair of common darters mating in the late autumn sunshine

November

One of my November excursions took me to RSPB Fowlmere, between Cambridge and Royston, which is renowned for its water rails. I don’t think I’d ever seen one before but I was tipped off by a fellow naturalist that there was one in front of a particular hide, so I headed off there and there it was, busy foraging in the pond for the whole hour I sat there. It was very murky so the photographic conditions were difficult, but I managed to get a couple of decent pictures and I particularly like this one:

A water rail in the primeval swamps of Cambridgeshire!

And another of my trips in November was to Norsey Wood in Essex which is a very different ecosystem to Fowlmere, consisting of ancient oak, beech and birch wood. So in autumn the forest floor is a really good location for fungi and this fly agaric was one of a large group growing out of the leaf litter.


Fly agaric mushroom amongst the fallen beech leaves of Norsey Wood

December

And finally, a wildlife success story is the long tailed tit. Until the last 10-15 years I only saw these occasionally but they now seem to be common, in direct contrast to so many other species of bird whose numbers are declining. I regularly see flocks of long tailed tits on the feeders in my garden and in the hedgerows and woods around Histon. They’re gorgeous little birds and I love watching a flock of them follow each other one after the other along a hedgerow before bunching together when they have found a food  source and then heading off again in line astern.

A long tailed tit in the hedges along Guns Lane in Histon

I stood quietly for several minutes watching the flock of around 15 birds that this one belonged to and they didn’t seem at all bothered by me as they picked insects from the trees.

So there you have it. 2011 in pictures. If you had the stamina to get this far, thankyou and I hope you enjoyed it.

Best wishes for a very happy Christmas and a peaceful and successful New Year from The Naturephile!

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.