Sheer wacky

I live in north-west London, not far from Brent Reservoir (popularly known as the Welsh Harp after a long-gone waterside pub that laid claim to the lake more than a century ago). Next to the reservoir’s northern branch is a new housing development called Hendon Waterside, where some of the homes are reached via a newly constructed cul-de-sac that has been given the name Shearwater Close.

Presumably this name was intended to reflect the site’s waterside location, but the choice of "shearwater" is sheer wacky because shearwaters are birds of the vast oceans. They spend their lives far out at sea except when breeding, and they certainly don’t breed anywhere near Brent Reservoir. They make their nests in burrows on remote rocky islands, which they approach only under the cover of darkness.

Very few shearwaters have ever been recorded in the London area, And those that have somehow made it into the metropolis have only ever been seen on or close to the Thames rather than in suburbia.

Almost all London's shearwater records relate to the Manx Shearwater, which occasionally in autumn will penetrate the Thames estuary as far as Thamesmead. Extremely rarely, one may even reach a Thames Valley reservoir upstream of London.

But these inland birds often appear exhausted or disorientated. In 2008, a frazzled bird was found in a communal bin-shed in Paddington. In 2009 one was dozy enough to be caught and eaten by a Great Black-backed Gull near the M25 Dartford Crossing. And in 2012, another pooped bird was picked up in Kensington Gardens.

Only two other species of shearwater have ever been recorded in the London area — a Macaronesian Shearwater found dead in south-east London in 1912, and a befuddled Balearic Shearwater seen at a Thames Valley reservoir in 1984.

Although Brent Reservoir has birding records going back to its construction in the 1830s, no shearwater has ever been reported there. But the reservoir happens to offer a wide range of birds that could have provided an appropriate name for the housing estate’s dead-end road. Since the chance of spotting a shearwater near Shearwater Close is virtually nil, how about changing the road's name to an alliterative Coot Close or Cormorant Close? 

Or perhaps Cuckoo Close would more closely reflect the daffiness of the site's developers.

STOP PRESS: Since I wrote this piece, another species of shearwater has been recorded in London: on the morning of 15 September 2016, a Cory's Shearwater was seen and photographed flying south-west over The Regent's Park.  

What is a seahawk?

I have no interest in American football, but I happened to read recently that on 2 February the Seattle Seahawks won their first Super Bowl Championship, thrashing the Denver Broncos 43–8. Now I know what a bronco is, but what on earth is a seahawk? It is not a name used by ornithologists.

Before every home game, the Seattle Seahawks release a trained hawk to fly out of the tunnel ahead of the players. Their tame bird is an Augur Hawk (Buteo augur) named Taima (meaning “thunder”), but this African buzzard is not a seafaring bird and therefore cannot properly be called a seahawk. Its diet consists mainly of rodents, snakes, lizards, small birds, insects and road-kill — but not seafood.

Apparently the club wanted to use a trained Osprey (Pandion haliaetus), but because this is a native American species (although also found on almost every other continent), the US Fish and Wildlife Service would not allow its use for commercial purposes. So the team chose the Augur Hawk because it has vaguely similar markings. 

The name seahawk has occasionally been applied to the Osprey, but that description is inaccurate. Although its diet is mainly fish, the Osprey catches its prey in freshwater lakes, or sometimes brackish estuaries and sea lochs, rather than in the open sea. 

It has also been suggested that the term seahawk might refer to skuas rather than Ospreys. The skuas are a group of seven species of seabird that look more like gulls than hawks. Many skuas are kleptoparasites, meaning that they steal food from other birds. A skua will wait until a gull, tern or auk has caught a fish and then attack it, forcing it to drop its catch so that the skua can snatch it.

Skuas will successfully plunder the catches of birds several times their own size. In winter they obtain most of their food through such theft, but at other times of year they eat the eggs and young of other seabirds. The larger skua species also kill and eat adult seabirds.

If I played American football, I am not sure I would want to be compared to such a predatory creature.

Avoiding snarge

Have you ever come across the word “snarge”? If you have not and you have a delicate stomach, then STOP READING RIGHT NOW. 

Snarge is the remains of birds that have collided with aircraft — the bits of flesh and feather, blood and beak that are left smeared across a plane after a bird-strike. No one is sure where the term originated, but it is certainly an evocative expression.

The study of snarge is important in ensuring air safety, since collisions with birds can lead to planes crashing. A well-known incident occurred in January 2009 when a plane taking off from New York’s La Guardia airport hit a flock of Canada Geese at an altitude of about 3,000ft. The pilots saw their windscreen turn dark brown and heard several loud thuds. Then the engines died and the cockpit was filled with the aroma of barbecued wildfowl. The plane ditched in the Hudson River — luckily without loss of human life. However,  worldwide more than 150 people have died as a result of bird strikes over the past 20 years or so.

When a bird strike occurs, air accident investigators need to determine the species involved so that they can work out ways of keeping the birds and the planes apart, in the interest of both air safety and the survival of the species involved. They therefore sample the snarge so that the birds can be identified. The standard collection technique involves spraying the besnarged area with water and wiping it with a clean rag or paper towel, which is then sent away for analysis. 

In the US, some 4,000 snarge samples a year are sent to the Feather Identification Laboratory at the Smithsonian Institution’s National Museum of Natural History in Washington, DC. When whole feathers can be retrieved, they are matched against the specimens in the museum's collections. When feather remains are too severely damaged for naked-eye identification, microscopes are brought out and the snarge is compared with thousands of slides of feather barbs. And if there is not enough feather even for microscopic comparison, DNA is extracted from the snarge and matched to a database of DNA records from tens of thousands of species.

A quackpot myth

On 7 February 2014, a new television comedy panel game show begins (or began, depending on when you are reading this) on Sky1, presented by Lee Mack, one of my favourite comedians. In each of the eight episodes, three celebrities aided by in-house boffins present weird “facts” and attempt to prove whether they are true.

The title of the show is Duck Quacks Don’t Echo. This is a reference to a popular belief that, er, duck quacks don’t echo.

The idea that the quacking of a duck does not reverberate, and that nobody knows why, has been widely repeated by such authoritative sources as Twitter feeds, online blogs, email trivia lists and even fruit drink bottle caps. The concept is, of course, completely quackers. Why on earth would the call of a duck be exempt from the acoustic laws that apply to all other sounds? 

But the myth is not so crackers that it has been ignored by academic researchers. I learnt recently that a few years ago acoustics scientists at the University of Salford investigated this fantasy with the co-operation of a duck called Daisy (species not disclosed, but presumably a farmyard-type Mallard), which they had recruited from a Cheshire farm. (I have no idea who was stupid enough to fund the research.) 

When Daisy was recorded quacking in an anechoic chamber and also in a reverberation chamber, it turned out that there was no echo in the former (which is, of course, why it is called anechoic) but a reverberant echo in the latter. Surprise, surprise!

If you wish, you can listen to samples of Daisy Duck’s various echoic and anechoic quacks at www.acoustics.salford.ac.uk/acoustics_info/duck. 

Sadly, shortly after the university relieved Daisy of her scientific duties and returned her to her farm, she became dinner for a local fox and has therefore quacked no more. 

But how did the quackpot duck-quacks-don’t-echo myth arise? 

One theory is that although quacks may echo, ducks rarely loiter near suitable reflective surfaces. An echo is only generated if there is a nearby smooth surface, such as a cliff face, positioned at an appropriate angle to bounce the sound back to the listener. 

A second theory is that because quacking ducks — such as female Mallard and Gadwall — tend to quack fairly quietly, their echoes are too quiet to hear. 

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. 

  

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.