Category: Biology

UPDATE: The purring call of the male Turtle Dove was in halcyon days of yore very much the sound of the English summer, long before the Collared Dove arrived on these shores around the time of World War II.

It was with great pleasure that summer of 2018, we’ve been places where we’ve heard several. Dog walking in Rampton, Cottenham (South Cambs), and camping in Snettisham (North Norfolk). There were at least three not far from where we pitched our tent.

I should perhaps have saved this bird for the Christmas edition given its pride of place in the “The Twelve Days of Christmas” the familiar gift accumulation song of 1780, thought to be French in origin that has the generous benefactor donating “two turtle doves” to their true love along with various leaping lords, pipers, milkmaids, drummers and of course a partridge in a pear tree.

I’m afraid I’ve only got one turtle dove (Streptopelia turtur) to give you anyway. This specimen had turned up on the day we visited RSPB Bempton Cliffs in June 2017 to see the puffins, gannets, guillemots, razorbills and others that live on the cliffs there. It was ground feeding among the jackdaws, chestnut-capped tree sparrows (Passer montanus), the more familiar, yet not native, collared doves, a pair of greenfinches (Chloris chloris), and a large brown rat (Rattus norvegicus) at the feeding stations close to the visitor centre.

The name of this bird comes from the Old English turtle, from the Latin turtur which is onomatopoeic given the bird’s purring call, trrr-trrr-trrrrr (as opposed to the more staccato coo-coo-coooh of the collared dove). The RSPB describes the turtle dove’s call as a “gentle purr…an evocative sound of summer”. However, it is not so often heard these days because of declining numbers, due to more efficient farming practices and a lack of wildflower seed and grain during its breeding season, habitat loss both here and in its wintering grounds. There’s also the issue of their being hunted in their millions on passage across Europe.

As such, the species is on the Red List of conservation concern. The RSPB offers farmers advice on encouraging this rare species here.

TL:DR – The bridled guillemot is a polymorphism (not a sub-species) of the Common Guillemot (Uria aalge) found in the North Atlantic region.

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Guillemot is the common name for various auk-type seabirds (Charadriiformes). In the UK, there are two genera commonly seen: Uria and Cepphus. Common Murre, also known as the Common Guillemot (Uria aalge) is a large auk with circumpolar distribution. It spends most of its time at sea. It breeds on rocky cliff shores or islands. The Bridled Guillemot is a polymorphism of the species found in the North Atlantic region.

My photo shows a Guillemot at RSPB Bempton Cliffs on the coast of the East Riding of Yorkshire. If I told you that there is a species of guillemot known as the spectacled guillemot, you might imagine that this is she. However, this is actually a bridled guillemot. It’s not a distinct species but a genetic polymorphism of Uria aalge, the common guillemot (aka the common murre). This strain has thin white circles around its eyes that stretch back as a thin white line. By contrast the spectacled guillemot is rather distinct looking and has thick white circling around its eyes and no “bridle” and is Cepphus carbo.

It’s a couple of years ago that we last walked the clifftops along the East Yorkshire coast of the Wolds spotting gannets, guillemots, razorbills, kittiwakes, and, of course, puffins. The day we arrived coincidentally, RSPB Bempton Cliffs had featured on BBC Springwatch because they were opening their new visitor centre. It’s all well heeled in now and armed with the Sigma, I thought it was time I got some new shots of the seabirds.

First up, everyone’s colourful favourite the Atlantic, or common, puffin (Fratercula arctica). There were a few around but not nearly as many as we’d hoped and I don’t think we saw any chicks. Certainly didn’t see any with food in their mouths for the RSPB’s competitive hashtag, #ProjectPuffinUK. Here’s the shot that was closest I got to one.

The common puffin is an auk, the only puffin native to the Atlantic Ocean, breeding in Iceland, Norway, Greenland, Newfoundland, and many North Atlantic islands, and as far south as Maine in the west and the British Isles in the east. Although it has a large population and a wide range numbers have declined rapidly recently in some parts of its range it is rated “vulnerable” by the IUCN. It swims on on the surface of the sea and dives to feed on small fish.

Early evening walk (31st May 2017, farmland south of Rampton, Cambridge, relatively close to the Guided Busway), hoping to catch sight of our local fen edge barn owl (Tyto alba), but could hear a cuckoo (Cuculus canorus) in a field beyond a hedgerow…call seemed to be getting closer…at which point two males flew over our heads calling, each presumably attempting to out court any nearby females. Female song is very different from that of the male and not heard so often. I got a quick shot of one of the two as they passed overhead calling all the while and they separated in their ongoing search for cuckoo nookie.

The male’s call is familiar to many people even if they have never seen this thrush-sized bird that resembles a small bird of prey, but is neither thrush nor raptor.

I suppose it was obvious in hindsight, it was RSPB Fen Drayton Lakes, there were reeds, there was warbling, it was a reed warbler (Acrocephalus scirpaceus). Despite his whitethroat and white rings around the eyes, he’s simply not a whitethroat (Sylvia communis). He wasn’t singing the whitethroat tune either.

Bird expert and friend Brian Stone explains: “Subtle but distinctive, the head shape is typical of the Acrocephalus warblers. Rather pointy with a steep forehead. That genus also tends to be very uniform in colour and many species are extremely difficult to separate if not singing. Fortunately we only have two really common species here and sedge warbler looks rather different.

Indeed, I had seen and identified positively sedge warbler recently at RSBP North Warren on the outskirts of Aldeburgh, north on the way to Thorpeness, and had seen said sedge warbler again not a few paces from the reed warbler.  Brian tells me: “Much more streaky and with a very bold face pattern. Reed Warbler goes much more for the no-nonsense brown on top, pale buff underneath approach.”

To me, it will always be Swavesey Lakes, but when the RSPB took on the old gravel pits that lie north of Fen Drayton, south of Holywell and west of Swavesey, they deemed a name change was in order, as I understand it.

The lakes, riverside, traditional meadows and hedges are linked by a network of paths and alongside is the Great River Ouse, which begins in Syresham in South Notts winds its way through East Anglia to The Wash. It’s a lovely site, you’ll see vast starling murmations at dusk in the early autumn, but at this time of year it’s a flutter of activity from countless feathered friends.

We parked up at about 10 on the late May Bank Holiday Monday in 2017, and could immediately hear willow warbler, chiffchaff, great tit and a couple of distant cuckoo.

Overhead what I thought was probably a marsh harrier or two, but actually realise now they were red kite. On the “board” promise of a bittern and oystercatchers with young. We saw a colony of greylag geese with goslings on the opposite bank of the River Great Ouse, but no other obvious bird young. The greylag’s had neighbours too: Egyptian geese.

On the pontoons that festoon some of the lakes there were plenty of black-headed gulls nesting and some common tern. On the outcrops into the lakes and the water’s edges: mallard, tufted duck, lapwing, mute swan, great crested grebe, redshank, cormorant, pochard, grey heron, and various others.

In and around the trees: blackcap, sedge warbler, long-tailed tit, robin, blackbird, wood pigeon, chaffinch, chiffchaff, goldfinch, collared dove. And, among the reeds, reed bunting, whitethroat, and reed warbler too. And a pair of nuthatch, based on a fleeting glimpse of two small birds with blue-grey colouring and rusty flanks and a monotonic and repetitive whistling.

Overhead Canada and greylag geese, mute swans, housemartins, barn swallows, and others.

Having heard the cuckoo there was always the hope of spotting one of these rapteurish-looking parasites, but we were not in luck.

I was also hoping to catch a shot at a yaffle or two (green woodpecker, in French: Picvert, “green pick”). As we drove off the site, there were lots of LBJs and we almost ran over a yaffle, which took to the air just in time. The female partridge on the opposite side of the road barely flinched and the female yellowhammer just flew.

I should point out that we were there in the middle of the day, a dawn or dusk visit would be much more fulfilling given the dawn chorus or the twilight hunters and the birds coming home to roost, respectively.

 

Walking the dog at dusk out on the Cambridgeshire fens mid-May, lots of swallows around, meadow pipits, yellowhammers, the inevitable wood pigeons, collared doves, starlings and blackbirds, a few LBJs (little brown jobs), chaffinch, house martins, robins, (barely glimpsed, but certain) goldcrests and more. Heading along the lode thought I saw a little egret out of the corner of my eye, but turned to see a beautiful barn owl (Tyto alba) in the lowering sun circle the fields, hunting small mammals, worrying the skylarks on their nests.

The shot above was the first I captured, it’s often the way, first shot on the reel is the best, the most spontaneous, the one that’s just right, the subsequent photos are as the owl passes by and so mostly rear-end shots. He did bank around again and fly towards us a couple of times, taking no heed of our presence nor of the dog, and not even the sound of the camera’s shutter distracted from his time to pray. Here he is being defined in his nomenclature by the that most obvious of farm buildings, a barn.

He circled back around of the field on our side of the lode and we watched as he dived down, emerging from the long grass a few seconds later with a shrew in his talons before heading off in the direction of a patch of woodland (ironically close to where we’d parked the car).

It must be ten years since I last got a photograph of a barn owl. We’ve seen a few and certainly enjoyed watching one range alongside the car in the Yorkshire Wolds a couple of years ago, presumably hoping our wheels would disturb the roadside mammalia into scurrying.

Barn owls are well known as silent fliers. Their wings are huge compared to their body size and mass, they are also curved. Both characteristics are evolutionary adaptations to their hunting technique. They can move very slowly with barely a flap even in the lightest of updrafts almost hovering over prey they have sighted. But, it is the structure of the feathers which makes them much quieter than other raptors allowing them to hear prey without the background noise of their own wings.

The barn owl’s wing feathers are soft which smooths airflow, reducing noisy turbulence. In addition, the leading edge of their foremost wing feather (the 10th primary) is fluted appearing to have tiny barbs (that have tiny barbs upon them) that break up the airflow hitting the wing and again reduce noisy turbulence.

It might be that the flutings raise the frequency (pitch) of the sound above that audible to prey and perhaps the owl too. Indeed, the owl’s silence does mean that it can hear its prey in the groundcover whereas other noisier raptors need to rely almost entirely on their sight (viz, the kestrel hovering high above likely targets).

Nice BBC program showing pigeon, peregrine, and barn owl in flight. The sounds they do or don’t make and the turbulence their wings do or don’t generate. It’s worth noting that pigeon wing flaps are thought to be a communication device too. Peregrines stoop on their prey so quickly and aren’t flapping when they do so any noise the make in normal flight doesn’t matter. Also, Barn Owls keep quiet not so that their prey don’t hear them, but so that they can hear their prey and home in on the tiniest rustle of blades of grass or the twitching of a rodent whisker.

The Great Spotted Woodpecker chick (Dendrocopos major) I have been photographing these last few days is getting very bold and almost bouncing out of his tree house when the adults visit with food.

I am surprised that there is only one chick, maybe nest size limits how many eggs the female lays. Either way, this little fellow with his red crown (does that make him a male?) is clacking away requesting regular invertebrate meals from the male (with the red nape to his neck) and female (black and white, but for her rump). Mrs Sciencebase reckons the clacking of the adults from neighbouring trees is probably encouragement for the chick to fledge (we’ve not heard much calling from them). The chicks head seems at least as big as his mother’s, so presumably he is almost read to leave the confines of his woody abode.

Here are a few more shots of male and female attending to the needs of the chick. That beak is sharp, makes sense for Dad to close his eyes while passing grubs beak to beak.