Dragonflies & Drones

One of my favourite summer activities as a child was pond-dipping.  I was fortunate enough to grow up in a house with a fairly large pond in the garden and so my pond-dipping activities often extended over days and weren’t as much dipping as a thorough exploration of the life in the pond.

Using a net and numerous containers of various sizes I would sift through the murky waters, peeling layers of rotting leaves apart, to see what might be hiding there.  Invariably anything alive would wiggle vigorously on exiting the pond so I would lay the contents of my scoops out and watch for movement.  Anything of interest would be plopped into one of my containers for closer inspection.

I was fascinated by the tiny bouncing daphnia or ‘water fleas’ that I would sometimes extract for even closer examination under a microscope.  Water beetles also scurried away seeking any corner they could find but best of all were the newts.  These tiny lizard-like creatures always delighted and were big enough to hold in the hand and examine close-up.

Just occasionally, another creature would appear amongst the siftings – a menacing-looking larva with six legs and bulging eyes.  Inhabitants of the dark recesses of the pond, these creatures, 3 or 4 cm in length, seemed to be from an alien world.  They were in fact dragonfly nymphs, biding their time at the bottom of the pond, eating voraciously and devouring whatever small creature crossed their path, from snails and tadpoles, to water fleas and worms.

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A Dragonfly nymph – photo by Vitalii Hulai (Shutterstock)

Fearsome predators, at least for much of the tiny pond life, I always handled these nymphs with nervous respect just incase (in my child’s mind’s eye) they nipped my finger.  Of course, dragonfly nymphs are prey themselves to larger aquatic life such as fish and birds but nevertheless, moulting up to fifteen times during their life in the pond, they can afford to lose a leg or two before their final form.

And that final form are the beautiful winged insects that we know and love, that having climbed heavenwards from the depths of the pond as full-grown nymphs, emerge in late spring and summer to whizz around bejeweling rivers and ponds with their sparkly metallic and iridescent colours.  Yet, in reality, we see only a brief few weeks of the dragonfly’s life for up to two years of its life is spent as a nymph growing in the shadows.

Every summer I would examine the tall flag irises at the pond’s edge to find the dried-out exoskeletons of the nymphs still clinging to the stems, a fading memory of a life spent in the dark underworld of the pond.  It is perhaps this murky past that has often given the dragonfly a sinister reputation in folklore.  Certainly, their huge, bulging, high-performance eyes give a sense of the alien and the discovery of their prehistoric ancestors with wingspans of up to two feet fuels the notion that these insects are from another world.

With the help of a number of fantasy movies it is not hard to imagine dragonflies and their nymphs being cast in some futuristic role to terrify us and threaten human extinction, but the future, as far as dragonflies are concerned, could be even stranger than science fiction.  Research engineers at Draper, a US research laboratory, have been working on a project called DragonflEye that blurs the lines between insect and machine. By genetically modifying a dragonfly’s nerve system the engineers are able to fit a tiny backpack to the dragonfly that ‘plugs-in’ to the insect’s nerve cord and allows engineers to steer the dragonfly remotely.  The result is a new kind of hybrid drone that combines miniaturized navigation, synthetic biology and neurotechnology to guide the dragonfly.

The ability to control such a small flying insect opens up incredible possibilities in many fields: for instance, it has been suggested that honeybees, whose population has collapsed by half in the last 25 years, could one day be equipped with Draper’s technology to assist with pollination.  I must admit that I personally find these developments far more scary than any fantasy film but recognise the significance of such pioneering work.

The technology is still being developed and we are hopefully a long way off seeing dragonflies with mini-backpacks on!  If there’s one thing that the research engineers agree on in trying to harness the dragonfly’s steering mechanism it is that the dragonfly itself cannot be improved on.  So let’s enjoy the real thing this summer – there’s nearly 60 species (including damselflies) to look for in the UK – and why not have a closer look at the reedy margins of ponds and rivers to see if you can find their empty nymph cases still clinging to the stems.

To read this article as it appears in the Herts Advertiser please click here.

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A Southern Hawker Dragonfly Aeshna cyanea – one of about 3000 species worldwide (photo by Steve Round)

 

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Make an Appointment with the Dawn Chorus!

This last weekend, on Sunday, it was International Dawn Chorus Day: an event instigated in the 1980s after Chris Baines, a then TV presenter, reputedly invited friends to celebrate his birthday at 4am so that they could listen to the dawn chorus of birdsong.

Of course, the dawn chorus had been going on for many millennia before that, but it was the official day established in 1987 that ever since has highlighted, celebrated and promoted one of nature’s great wonders and one which we, living in a temperate region of the world, get to enjoy every spring.

Living in suburban St Albans the dawn chorus in spring is almost guaranteed from your bedroom window wherever you live.  You may not think there are that many birds in your garden but thankfully birdsong is not defined or contained by our fences and boundaries.  Instead, quite the opposite is true as birdsong declares and defines nature’s boundaries through song.  The dawn chorus is a bout of aural jousting between birds that the writer and naturalist, Mark Cocker, describes as “their version of territorial warfare conducted through music”.

Rising to the top of the singing charts in spring is the Blackbird whose patient and quiet practicing of his song during the winter months from the dark depths of a bush finally pays off. His squeaky winter sub-song endured the punching tones of his relative the Song Thrush and now emerges as the sound of spring – a soft warbling meditation that is the soothing backdrop to every first barbecue.  The song brings a depth to spring and a richness that wasn’t there in the winter months for each Blackbird is answered by a rival bird, maybe a few gardens away, and that in turn is gently rebuffed by another even more distant bird.  A luxuriant layer of sound is added to our landscape and enriches the balm of a warm spring day.

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The Blackbird (Turdus merula) – photo by Mirko Graul (Shutterstock)

The name ‘Dawn Chorus’ is bit of a misnomer in that if you rise as the sun appears the chances are you will have missed the main performance that actually begins a good hour before sunrise. It may be that you are well aware of this having been woken recently, like me, well before the alarm clock is due to go off, by the repetitive ‘squeaky wheelbarrow’ song of the Great Tit or the angry cries of Crows seeing off a skulking fox before first light. This is no way to enjoy the dawn chorus and if there is one thing I would encourage every person to do this spring it is this:  to make an appointment with the dawn chorus and get out in it!

This of course means setting the alarm clock for 4am, maybe even earlier, and getting outside, ideally in as rich a natural habitat as possible.  Sticking your head out of the bedroom window will give you a taste of what’s on offer but to be out in nature as the dawn chorus swells, rises and unfolds all around you is intoxicating.  Birdsong is beautiful but when combined in unison with the first light of dawn, the sweet smell of May blossom and the cool dew on shining gossamer threads you are left looking for your next fix.

Every year I make a pilgrimage to Kent in May for a mad day of birdwatching – the rough aim being to see as many different birds in a 24-hour period as possible.  It is a hangover from university days when a group of us raced around Kent as part of a yearly countywide sponsored competition. However, it is not the ‘day count’ as such that draws me back and the competitive flavour to the day has long since gone:  it is the chance to be out in nature at dawn and experience one of the best dawn choruses that the UK has to offer.

In an undeniably crazy rejection of the messages our bodies naturally give us we start in a marshland setting at midnight where the birds never really go quiet.  Bitterns boom, cuckoos call and marsh frogs holler – at times it is deafening.   We then move on to a parkland setting at 4am where the tentative song of redstarts ring out in the pre-dawn darkness, interspersed by the amphibian calls of roding woodcock and squeaking baby owls.  And then it breaks, slowly at first but quickly overwhelming:  the full voice of the parkland birdsong rises with the sun, banishing the lingering mist patches and warming every leaf in a carpet of song.

It is exhilarating, uplifting, deafening and any thoughts that it would have been better to stay in bed vanish as nature’s drug takes full effect.  My appointment with dawn is this Friday…when will yours be?

To read this article as it appears in the Herts Advertiser please click here.

 

Strange Summer Soundtracks!

 

Twice this year I have found myself listening to birds that do not sound at all like birds! The first occasion was whilst camping in Dorset amidst the wild and beautiful heathland bordering the edge of Poole Harbour…

On a still, warm evening in late spring and early summer you are almost guaranteed to hear the strange song of the Nightjar issuing out from dusk until dawn on the Dorset heathland. I say ‘almost guaranteed’ because on the very, seemingly perfect, night I chose to lead a small group out into the twilit heathland a deafening silence greeted us! We had to wait a long time but did eventually hear a distant male bird’s song, but not before my birding credentials had almost been teased to tatters. Of course, the very next night, the campsite itself played host to several male Nightjars happily calling loudly high above our tents!

The song of the Nightjar is best described as a continuous churring sound, rising and falling in pitch. If you hear it you may be forgiven for attributing it to an amphibian or even to a piece of machinery. The Nightjar’s song contains 1,900 notes per minute and in the warm, stillness of a summer’s evening, seems to fill the air, mixing with the rising heathland scent of heather and pine. It is a magical experience reminiscent of holiday evenings in the South of France listening to cicadas as the light fades and the day cools off. Perhaps this is what J.A. Baker had in mind as he wrote his beautiful descriptive prose of the Nightjar’s song:

Its song is like the sound of a stream of wine spilling from a height into a deep and booming cask. It is an odorous sound, with a bouquet that rises to the quiet sky. In the glare of day it would seem thinner and drier, but dusk mellows it and gives it vintage. If a song could smell, this song would smell of crushed grapes and almonds and dark wood. The sound spills out and none of it is lost.” (J.A.Baker, The Peregrine, 1967)

The bird itself is no less peculiar than its song with a wide, gaping mouth, reinforcing a sense of the amphibian. Indeed, its closely related family of foreign cousins are called ‘Frogmouths’. During the day, it remains perfectly hidden, its brown plumage matching the dry litter of the heathland floor – not revealing itself unless practically stood on.

Like the nighttime jarring of the Nightjar another, much smaller bird, has recently been singing its equally un-bird-like notes much nearer to home – at Heartwood Forest on the edge of St Albans. At this time of year, Heartwood is alive with the buzz of insects, cashing in on the abundant supply of nectar from the wildflowers blooming in the warm sun. Calling grasshoppers and crickets herald the start of lazy summer days while boisterous buzzing bees share petal space with the altogether quieter and more delicate butterflies.

Out walking the dog at Heartwood I paused to take in the scene and listen to the buzz all around me. As I listened I realized that above the stridulations of the grasshoppers a louder, more persistent ‘grasshopper call’ dominated. Almost identical to the song of its insect counterparts this was no insect but a little brown bird aptly named the Grasshopper Warbler.

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A Grasshopper Warbler – by Steve Round

Like the Nightjar’s song the Grasshopper Warbler’s reeling notes – likened to the sound of a free-wheeling bicycle or a winding fishing rod spool – rise and fall in pitch and volume as the little bird, its whole body vibrating with the sound, turns its head this way and that. The resulting ‘spray’ of notes has a ventriloquistic quality making it very difficult to locate the bird, often perched just above the long grass on a twig or bush.

Once spotted, the little bird is nothing much to look at with its mottled brown plumage and bright pink legs. Like the Nightjar, the Grasshopper Warbler is perfectly camouflaged and designed to remain hidden and, as a result, both birds are heard far more often that they are seen. This visual secrecy seems to amplify their strange un-bird-like songs and, although unlikely to be heard together, add a layer of mystery to the summer landscape wherever they sing.

The Nightjar is sadly now absent as a breeding bird in Hertfordshire but, as I write this, the Heartwood Grasshopper Warbler is still singing his heart out and proving unusually showy. If you do get a chance to hear him, or indeed a Nightjar elsewhere in the country, I’m sure their strange summer soundtracks will captivate you!

Published as Nature Notes in the Herts Advertiser on 13th July 2017