Thursday 22 August 2013

Sandpipers that don’t pipe on the sand

During recent visits to the hides at a local mud-fringed reservoir I have enjoyed watching Green Sandpipers and Common Sandpipers, among other passage migrant waders. 

While observing (and attempting to photograph) these birds, I have mused over the name “sandpiper”. This monicker is sometimes applied to the whole Scolopacidae family, a large group of waders that certainly includes some sand-loving birds, such as the Sanderling. But what about those birds whose English names actually include the word “sandpiper”?

Around the world you can find more than 20 species named as sandpipers, but I can think of only one that can actually be found piping on the sand — and that is a bird only found thousands of miles from the UK. 

Despite their name, most sandpipers avoid the seashore. Instead, they feed around the muddy margins of freshwater lakes and ponds, where they eat small invertebrates picked out of the lacustrine gunk. Most of them breed in bogs in the Arctic tundra or taiga and spend the winter around inland lakes in the southern hemisphere. 

The few sandpipers that can be seen at the seaside usually avoid sandy beaches. They either feed on rocky shorelines (Purple Sandpiper, Rock Sandpiper) or forage in salt marshes (Curlew Sandpiper, Broad-billed Sandpiper). Some others tend to avoid wetlands altogether and prefer to feed on open grassland (Upland Sandpiper, Buff-breasted Sandpiper). 
  
And the one sandpiper that actually enjoys a day at the beach? It is the endangered Tuamotu Sandpiper, endemic to French Polynesia, where it breeds only on a few rat-free atolls in the Tuamotu archipelago. This rare bird is not closely related to other sandpipers, but since it can actually be found on sandy shores and also has a piping call — unlike the whistles, trills and chirps of other sandpipers — it appears to be the only wader that actually pipes on the sand.

However, I must admit that the name “sandpiper” has a pleasant ring to it. I certainly wouldn’t want any British sandpipers to be renamed bogwhistlers, pondtrillers or mudchirpers. 
  

Monday 1 July 2013

Dodgy transcriptions of birdsong

One of my favourite television programmes is BBC Four’s Only Connect, in which contestants have to find the links between sets of words, phrases, symbols, images or musical extracts.

In an episode broadcast on 1 July 2013, one question asked for the connection between the phrases “My toe bleeds, Betty”, “Teacher! Teacher!”, “Who cooks for you?” and “A little bit of bread and no cheese”. 

I realised the answer after the appearance of the second phrase, which is a common representation of the typical song of the Great Tit. My solution was confirmed by the fourth phrase, which is a well-known, if not particularly accurate, transcription of the song of the Yellowhammer. And the official solution was indeed “transcribed versions of bird calls”. 

But I admit to being flummoxed by the first and third phrases. In my innocence I was not aware that “My toe bleeds, Betty” supposedly describes the song of the Woodpigeon. According to the British Trust for Ornithology website, other transcriptions of the wood pigeon’s song include “Take two cows, Taffy'” and “A proud wood-pig-eon”. So far as I am concerned, none of these dodgy phrases sounds much like the pigeon’s song, which to my ears is usually “ROO-coo-coo, roo-coo [repeat two or more times], coo”. That final “coo” is a distinctive part of the song — a coda, if you will.

(By the way, the BTO website uses both “wood pigeon” and “woodpigeon”. Some consistency would be appreciated.)

I also learnt from the BTO website that the Collared Dove’s song, simpler than that of the Woodpigeon, is supposedly akin to a football fan chanting “un-it-ed, un-it-ed, un-it-ed”. Rubbish! To my ears, the song is a simple “roo-COO-coo”, repeated as nauseam. 

And what about “Who cooks for you”? The answer given on Only Connect was the Barred Owl, with no explanation that this is a north American bird rather than a British species like the Woodpigeon, Great Tit and Yellowhammer. And the alleged transcription of the owl's call is inadequate, since it usually makes its presence known with a series of eight accented hoots ending in “oo-aw”, with a downward pitch at the end. The most common mnemonic device for remembering it is not a mere “Who cooks for you” but “Who cooks for you, who cooks for you all.”

Despite this gripe, I recommend Only Connect to all readers of this blog. 

Thursday 11 April 2013

A pointless complaint

Pointless is a BBC quiz show in which pairs of contestants are faced with multiple-choice questions and have to find correct answers that have been chosen least often by a random selection of 100 members of the British public. As the game progresses, unsuccessful contestants are eliminated until one couple remains to face the final round and a possible monetary prize. 

On 10 April 2013 I watched an episode of Pointless in which, at the penultimate stage, the two remaining couples were asked to identify British birds that have two-word names. They were shown photographs of five birds, which were labelled as ---- Thrush, ------ Duck, ---- Bunting, ---- Wagtail and -------- Dove. 


Both couples chose to name the Wagtail, with one couple identifying it as a Grey Wagtail and the other pair as a Blue Wagtail. Both were wrong, because the Grey Wagtail is an altogether different bird and the Blue Wagtail is a tropical fish. The correct answer was Pied Wagtail.

Except that it wasn’t. 

The name Pied Wagtail is applied only to the British and Irish subspecies of the White Wagtail. Known to its friends as Motacilla alba yarrellii, the Pied Wagtail can easily be identified by its black or dark grey back, but the bird illustrated, with its pale grey back, was clearly a White Wagtail of the continental European nominate race, Motacilla alba alba

(Several other White Wagtail subspecies can be found across Asia and north Africa. They have been given names such as Moroccan Wagtail, Masked Wagtail, Black-backed Wagtail, Amur Wagtail and Indian Pied Wagtail.) 

Incidentally, as many as 47 of the 100 randomly selected people described the wagtail as a Pied Wagtail. Only the Song Thrush was more frequently identified, with 50 subjects able to name it. The pigeon was correctly identified as a Collared Dove by 23 of the 100. Perhaps surprisingly, more people were able to name the rare Snow Bunting (12/100) than could identify the much commoner Tufted Duck (7/100).


[And when the episode was repeated on 16 March 2015, there was no acknowledgement of the Pied/White Wagtail error.]

Friday 29 March 2013

Unintellyjent, indyjestible distortion

Last winter, when I wanted to stock up on the Niger seeds that attract Goldfinches and occasional Lesser Redpolls to my bird feeders, I made a point of buying them from a market stall that labelled them as such rather than from a large store that offers “nyjer” seeds. This crass distortion of the word is both unintellyjent and indyjestible, and I personally shall stick intransyjently to the original spelling. 

Niger seeds are so named because they come from a plant that has been widely cultivated along Africa’s Niger river as an oilseed crop. We are oblyjed to the US bird seed industry for the bastardised spelling. Allegedly to clarify pronunciation, the change reflects squeamishness about Niger’s similarity to “nigger” — even though the river’s name seems to be derived from the oryjinal Arabic Ni-Ghir rather than from the Latin for black. 

Confusion may have occurred because the tiny Niger seeds are themselves black. They are the fruits of Guizotia abyssinica (Asteraceae), an annual herb related to the sunflower. It is indyjenous to the Ethiopian highlands but now cultivated elsewhere, particularly in the Indian subcontinent. In many places, it is an important oilseed crop. Its seeds typically contain about 40 per cent oil, with a fatty acid composition mainly of linoleic acid.

In its native Ethiopia, Niger seed supplies 50 per cent of all cooking oil. It is also used in soap and paint manufacture, as an illuminant in oil lamps and as a lubricant. The protein-rich meal that remains after oil extraction is widely employed as an animal feedstuff, a fertiliser and a fuel.  

Niger seeds have also been used in traditional medicine by the aboryjinal peoples of Nigeria (Nyjeria?) and the Republic of Niger (Nyjer?). The oil is applied to treat rheumatism and burns, and a paste of the seeds is used as a poultice to treat scabies. 

Niger seeds imported into Britain as bird food are now dilyjently heat-sterilised to stop them germinating. However, earlier neglyjence means that Guizotia abyssinica can be found growing bellyjerently across some tracts of southern England. 

Thursday 28 March 2013

A pharmacist with a lot to answer for

The Common Starling, Sturnus vulgaris, is found naturally across Europe and western Asia. It is abundant in the UK in winter, when dense flocks of visitors from the east can sometimes be seen at dusk wheeling across the ashen skies before settling down to roost. 

As a pharmacist, I wish to apologise for the actions of a fellow pharmacist 120 years ago. It is thanks to the efforts of this eccentric and misguided New Yorker that the starling is now also to be found coast to coast across North America, as far south as northern Mexico and as far north as sub-Arctic Canada and Alaska. 

The starling’s New World population is now estimated at more than 200 million. In the US, it is generally reviled and is officially branded as a serious pest. It is accused of damaging crops and harming native bird populations by aggressively competing for nest cavities.   

The pharmacist who must take the blame for all this is Eugene Schieffelin (1827–1906). He was a leading light in the American Acclimatization Society, which was founded in 1871 by a group of wealthy New Yorkers who had been trying to introduce European flora and fauna into North America for economic and cultural reasons. The society wanted to establish European birds that were “useful to the farmer and contributed to the beauty of the groves and fields”. These species included the Skylark, Starling, Blackbird, European Robin, House Sparrow and Chaffinch, all of which were released into the city’s Central Park with the approval of the park commissioners. Apart from the House Sparrow — now also found throughout North America — none thrived, even the Starling.

But Schieffelin, the society’s chairman and driving force, was determined to try again and in 1890–91 he released another few dozen Starlings into Central Park. From these few are descended today’s many millions.

Some say that Schieffelin, a Shakespeare enthusiast, wanted New Yorkers to experience every wild bird mentioned in the Bard’s plays. But there is no convincing evidence for this, and apart from the Starling, which the playwright mentioned only in Henry IV, Part 1, he would have had to introduce nearly 50 species, including even the Ostrich.

Colourful winter visitor


The Waxwing (Bombycilla garrulus) is a plump, colourful, starling-sized bird that breeds in the coniferous woodlands of northern Scandinavia. In most winters a few migrate to the east coast of Scotland and northern England but occasionally they arrive in huge numbers and spread out across the country. In 2011-12 and 2012-13 Britain saw two of its biggest ever Waxwing irruptions.

You do not have to be a birder to get excited when Waxwings turn up in your garden. They quickly attract attention with their distinctive sandy-pink plumage, a large punkish crest, a black bib, yellow tips to the tail feathers and white markings in the wings. 

Their name derives from the bright red tips to the secondary flight feathers. These resemble a splash of the red sealing wax that ancient pharmacists (like me) will remember using to seal the white demy paper in which they once wrapped prescription medicines.

In winter Waxwings feed mainly on berries. They are fond of rowan and hawthorn but are also partial to cotoneaster and other garden shrubs. They are often seen in tight flocks that spend much of their time calling loudly from the tops of tall trees but then suddenly drop into a bush full of berries. After feeding frantically for a few minutes, sometimes completely stripping the bush, they return to their treetop vantage points. In January 2012, near my London home, I watched a flock of about 250 feeding in this way — until an urban Sparrowhawk swooped in and scattered them. 

Although they have a nervous manner, Waxwings can be remarkably approachable. They will usually let you sidle up to within a few feet of them before they fly. With patience, you may even be able to tempt them to feed from your hand.

In Britain, Waxwings have a reputation for frequenting supermarket car parks, feeding from the berry-bearing trees that are often planted in such places. I suspect that our commoner berry-eating birds, being more timid, are deterred by the dawn-to-dusk presence of shoppers and so leave the fruit on the bushes for the bolder visitors from the north. 

Mystery of the toxic quail


Common Quail (by Callie Jones)
Some 3,500 years ago, according to the Bible, Moses led the Israelites out of Egypt into the wilderness. When they became hungry and demanded flesh to eat, God sent a wind that deposited quails for miles round their encampment. But when they gathered and ate the quails, “the Lord smote the people with a very great plague” (Numbers 11:31–33).

Later, ancient Greek and Roman writers also described sickness after consuming quails, and severe illness still occasionally afflicts quail-eaters — sometimes killing elderly victims. 

The sickness, known as coturnism, is caused by a toxin in the fat and flesh of the wild European Quail, or Common Quail, Coturnix coturnix. The toxin causes rapid breakdown of skeletal muscle (rhabdomyolysis), leading to muscular weakness and producing breakdown products that damage the kidneys and may lead to acute renal failure. Other symptoms include vomiting, respiratory distress, excruciating pain and paralysis. Sufferers who recover may take 10 days to get over the symptoms. 

The whys and wherefores of coturnism are a mystery. Although there are various other species of quail, only C coturnix has been implicated in the syndrome. And the toxicity occurs only during certain stages of migration and by no means in every bird. 

European Quails are tiny game birds that feed on seeds and insects. They spend the summer in Europe and the winter in sub-Saharan Africa. They follow two main migratory routes, with some crossing the Mediterranean at its eastern end and others at its western end. Toxicity in birds using the eastern flyway occurs only when they migrate south in autumn, while in those using the western flyway it occurs only during the northerly movement in spring.

It has been suggested that coturnism is caused by alkaloids (coniines) in the flesh of birds that have fed on the seeds of hemlock, Conium maculatum. But hemlock cannot be responsible for all cases because it is not in seed in spring when western flyway birds are toxic. The quails must therefore derive their poison from other food sources. 

Another plant named as a suspect is the annual yellow-woundwort, Stachys annua, which sets seed in the various parts of its range at the same time as the quails become toxic. Its seeds have been found in the digestive tracts of quails that have caused coturnism, but investigators have as yet failed to identify any toxins in the seeds. 

Definitive research is needed before the mystery of coturnism can be fully explained.

A nightingale sang . . .

The Nightingale is famous for its song, but I suspect that few Brits have knowingly heard one singing. The bird is a scarce summer visitor to southern England, where it usually keeps to dense woodland well away from human habitation. Since the males sing only for a few weeks, and mainly during unsociable hours, they are not often heard.

Contrary to popular belief, Nightingales do not sing only at night and they do not always skulk out of sight. From mid-April until early June, after which they are too busy feeding their young, male Nightingales will usually sing most mornings, sometimes out in the open on the top of a bush.

The Nightingale’s astonishingly varied song consists of a succession of rich whistles, trills and gurgles that no other British species can match. The song is so multifarious that a bird can sing for two hours before it begins to repeat any phrase.

Any attempt to transliterate the song has to be inadequate, but one of the best attempts was made in 1832 by the poet John Clare, who heard one singing outside his window. He transcribed the song as: “Chew chew chee chew chee / chew — cheer cheer cheer / chew chew chew chee / up cheer up cheer up / tweet tweet tweet jug jug jug / wew wew wew — chur chur / woo it woo it tweet tweet / tweet jug jug jug”.

I have been privileged to listen to a Nightingale singing its little heart out in suburban London — in a public open space only some six miles from Berkeley Square and about the same distance from anywhere you might be tempted to describe as rural.

The bird arrived in April 2007. Although its song had to compete with the noise of the traffic on one of London’s busiest roads, it managed to attract a mate and the pair nested in a tangle of brambles close to a picnic table and just yards from the park’s main footpath, which forms part of the Capital Ring walking route encircling inner London.

To protect the birds from unwarranted disturbance, the local birding group made a decision not to broadcast the news. Those in the know avoided loitering near the nest site so as not to draw attention to the birds.

To the delight of this privileged in-crowd, the birds reappeared in 2008 to raise another family. But sadly they failed to return in 2009.

Incidentally, the song “A Nightingale sang in Berkeley Square”, published in 1940, is not based on a genuine occurrence of the species in central London. Indeed, it was written in a fishing village on France’s Medi­terranean coast. Any bird heard singing at night in Berkeley Square is likely to be a Robin — a species that can often be heard throughout the night in London’s well-lit streets.

Thursday 21 March 2013

Why Countryfile needs a bird expert

I enjoyed the recent BBC Two five-part series on The Great British Winter (4-8 March 2013), made by the Countryfile team. But I was puzzled by a couple of clips of feeding geese in the fourth episode, which concentrated on estuaries and was mainly filmed around Morecambe Bay. 

While the presenter (Ellie Harrison) was visiting the cabin home of a driftwood artist somewhere on the edge of the bay, the cameras showed the view of the seashore from his balcony and then cut to a close-up of two feeding geese, without any mention of them in the commentary. Later the presenter visited Leighton Moss nature reserve, 4km inland from the bay, where she sat in a hide with a local expert who pointed out waterfowl such as Teal and Wigeon. During this sequence the cameras again cut to the same two geese, clearly in exactly the same place as before, and again without any mention.

So the programme implied that the same two geese were seen in two different locations. And on both occasions it failed to identify them. This might have been forgivable if the geese had been common birds, but they were in fact Emperor Geese and representatives of a near-threatened species. 


The Emperor Goose breeds in the coastal salt marshes of Alaska and Siberia and winters around the northern Pacific Ocean. Its global population is less than 75,000. No Emperor Goose has ever been known to reach Europe unaided, and sightings of escapes from collections are virtually unknown in Britain — apart from a small breeding flock of about a dozen birds that has in recent years frequented the bleak shores of Walney Island, on the north-western edge of Morecambe Bay. The geese that were shown twice during the Countryfile estuaries episode are presumably from this flock. Information about them would have improved the programme.
  
This is not the first occasion on which Countryfile's programme-makers have included footage of a rare bird without realising that it was worthy of comment. On more than one occasion I have seen rare birds misidentified — notably a White-tailed Eagle described as a Golden Eagle and a feature on the Common Tern that included a film clip of Arctic Tern. The Countryfile team clearly needs the assistance of an expert birder. 

Friday 1 February 2013

Renaming bird species

I have found conflicting information in two books published by Collins. Try to look up any species of diver in the index to the well-known Collins Bird Guide, and you won’t find it. This is because the current (2nd) edition has unhelpfully dropped “diver” in favour of the American name “loon”, which is favoured by interfering taxonomists. Ironically, the Collins English Dictionary defines “loon” as “the US and Canadian name for diver”, without acknowledging any use of the word on this side of the Atlantic. 

And divers are not the only birds lost from the bird guide index. For example, there is no entry for Fan-tailed Warbler, because the taxonomy gestapo tell us that we should use the stupid name “Zitting Cisticola” to avoid confusion with a tropical American species also known as a Fan-tailed Warbler. 

But how can confusion arise? If anyone this side of the Atlantic refers to a Fan-tailed Warbler, the reference is obviously assumed to be to the Old World species. If the American bird is meant, it will clearly be identified as such.

Also missing from the Collins index is the Bearded Tit, because it now has to be called a Bearded Reedling on the ground that it is not a true tit but is more closely related to the larks. Do you know the expression "If it looks like a duck and quacks like a duck, it's a duck"? Well the Bearded Tit looks like a tit and it behaves like a tit, so why not call it a tit? 

The book’s editors have also behaved like tits, since, although they refuse to call the Beardie a tit, they have still placed its monograph in among the tits, where it sits nearly 100 pages after the larks! 

What’s more, many well-known bird species are now supposed to have their names burdened by qualifiers such as “Common” or “European”. If we just look at the waders, we find “Eurasian” Oystercatcher, “Pied” Avocet, “Northern” Lapwing, “European” Golden Plover, “Common” Ringed Plover, “Eurasian” Dotterel, “Eurasian” Woodcock, “Common” Snipe, “Eurasian” Curlew, “Common” Redshank, “Common” Greenshank, “Ruddy” Turnstone and “Red” Knot. These added adjectives are unnecessary because when we talk or write about such birds, the listener or reader will naturally assume we are referring to the regular European species. 

And some of the names that are supposed to avoid confusion are actually misleading. More than 300,000 “Red” Knot visit Britain every winter, when their plumage is predominantly grey, with not a trace of red. It is only while they are breeding in the high Arctic that they have a brick-red chest, belly and face. So why should British birders have to describe a clearly grey bird as red?

A similar situation applies to the rare winter visitor we know as the Grey Phalarope. This too develops a red undercarriage only while summering in the Arctic, but we are now expected to call it a “Red” Phalarope — a name that risks confusion with the less rare Red-necked Phalarope. 

Luckily, unlike those tits at Collins, most British birders have sensibly resisted attempts to bludgeon them into abandoning bird names that have been familiar for many, many years. We continue to talk about Bearded Tits, Fan-tailed Warblers and Grey Phalaropes without any risk of confusion. Long may we continue to do so.

Thursday 31 January 2013

The curse of Big Garden Birdwatch

What is it about the RSPB’s annual Big Garden Birdwatch weekend? Why do all the birds mysteriously disappear from my own garden? 

Normally on a fine January day I can look out of my suburban window and expect to see up to four species of tit (Great Tit, Blue Tit, Coal Tit and Long-tailed Tit) visiting my bird feeders, a Robin below them on the bird table and a Dunnock delicately pecking up food spilled onto the lawn beneath. 

Blackbirds are likely to be working their way clumsily through my berry-bearing bushes, perhaps joined by a few Redwing. One or two Woodpigeons will almost certainly be strutting across the grass. And Magpies and Jays may be driving the smaller birds away from the bird table.

If I am lucky, a Great Spotted Woodpecker may visit the bird feeders or a Green Woodpecker may fly down to peck at ants on the lawn. And this year an overwintering male Blackcap has been creeping about in my hedges.

The only RSPB-specified garden bird I do not expect to see is the House Sparrow, which disappeared from my area years ago.

But come Big Garden Birdwatch weekend, everything vanishes. Last year I sat at the window and watched a variety of birds flying over my garden or visiting neighbouring gardens. But they completely ignored my own blessed plot. After 20 minutes with not a single bird to record, I gave up. 

This year I again set aside an hour to watch the garden. It was a beautiful sunny morning after a long cold spell, and the birds should have been out and about feeding. But once again, the garden was empty. I had topped up the bird table and feeders and put out new fatballs, but the delicacies that had been so popular on the Friday were now no longer an attraction. In the first 10 minutes I counted 10 species — but all were either in neighbouring gardens or merely passing overhead. Even the Woodpigeons that normally spend all day on my lawn were laughing at me from a neighbour’s ash tree. So once again I lost interest and gave up. 

Guess what? On the Monday my garden was again alive with birds.

Friday 4 January 2013

Pigeons versus peregrines

From time to time, racing pigeon owners call for a cull of birds of prey to "protect" their own birds. Some have even taken matters into their own hands and illegally killed Peregrine Falcons.

Although it may be easy to blame a bird of prey when one of your pigeons fails to return to its loft, it seems that raptors actually account for only a small proportion of lost pigeons. Research cited in a 2000 report by the government-backed UK Raptor Working Group (on which pigeon racing interests were well represented) suggests two main reasons for racing pigeons failing to return to their lofts. It seems that at least 40 per cent of lost birds die through exhaustion or collision (with overhead wires, buildings, road vehicles, etc) and a similar proportion remain alive but either get hopelessly lost or choose to join a feral population. There is even some evidence that increasing numbers of pigeons are going astray because mobile phone towers interfere with their navigation, which depends of the earth’s magnetic field.


Evidence also suggests that most racing pigeons that succumb to raptors are already lost to their owners before they meet their end. One study of pigeon leg-rings retrieved from Peregrine nests concluded that more than 70 per cent of the victims had either gone feral well before being killed or were so far from their race flightpaths that they would never have returned to their owners anyway. 


Pigeon fanciers also tend to blame raptors for the disappearance of birds exercising near their lofts. But the evidence for this is slim. It appears that many pigeons, particularly young ones, simply decide to move on elsewhere. And those that are killed locally are more likely to be victims of the UK’s biggest slayer of birds — the domestic cat. 


Just look at the figures: we have about 7.5 million pet moggies and a further million feral cats. The Royal Society for the Protection of Birds estimates that cats annually kill around 55 million birds. In contrast, the UK’s latest estimated breeding population of Peregrines is just 1,402 pairs. So, if pigeon fanciers wish to protect their investments, shouldn’t they be calling for a cull of cats rather than of birds of prey?

Gulled by an aberrant gull

Leucistic Herring Gull
One technique used in the study of wild birds is ringing. Usually a small, numbered metal ring is placed round the bird’s leg, so that if it is later recaptured, or found dead, the ring may help provide information about migration, longevity and other aspects of its life. 

Some birds may also be fitted with brightly coloured plastic leg rings that allow them to be identified without recapture and therefore with minimum disturbance. Each bird is given a unique combination of small rings of different colours, which are read in a specific order. 

Larger birds may instead be fitted with rings bearing conspicuous letters or numbers that can be read in the wild with the aid of a telescope. I recently had an encounter with one such bird that has become something of a celebrity among London birders. 

I was sitting in a hide at a reservoir in north-west London when another birder thought he had spotted a rare Iceland Gull. But the bird soon turned out to be an aberrant example of a Herring Gull — a common species. The bird had extremely pale (leucistic) plumage, with all-white wings (like an Iceland Gull’s) rather than the Herring Gull’s usual grey wings with black and white tips. 

The four-character alpha-numeric code on its leg rings confirmed its celebrity status. The bird had been ringed a few years earlier by members of the the North Thames Gull Group, who use a cannon net to snare birds feeding on waste at landfill sites on the Essex side of the Thames estuary. Once caught, the gulls are extracted from the net and marked with numbered leg rings. Some, like the bird in question, are also given orange rings bearing large letters or numbers that can be read with a telescope. 

So is this gull’s celebrity due to its leucistic plumage? Not entirely. Its birding fame derives mainly from the characters on its four leg rings — S, H, 1 and T. These more or less spell out an expletive that birders may use when they realise that the pallid gull is not after all a rare species.