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When I posted Winter Swans, you might have noticed an amazing number of Coots in some of the images from Hogganfield Loch. I spent most of my camera time on the Goldeneyes and Goosanders, possibly mistakenly, because it is (in my experience) unusual to see many Coots in mutual proximity. Once they get to it in the breeding season, it’s serious “get orf my larnd” and  proper street fighting to follow. These chaps were going at it on Frankfield Loch.

I found some Coots very close to the lens at Hogganfield Loch and not shy – desperation suspending caution, probably. Through the water, you can see the extraordinary feet.

They do lend themselves to contrasty images but there is that really strange bit of pink on the bill which is missed in black-and-white.  

I have failed to find anything very interesting about their feet in the open literature but I did find a nice image at this site. I am made nervous by including this in my post as the headline appears to be the mating call of Gammonus brexitus (ssp. Clarksonii) but it’s a belting photograph of a Coot’s foot and I’m thinking that it would be unreasonable for these scaly semicircular flaps of skin to support the Coot as it prospects across rafts of weed on the canal margins, and propel it as it swims, folding back on the recovery stroke for less resistance. Thinking superficially about different types of proteins and their roles, there must be a few things going on here, with regions of hydrophobicity for the coating, stiffness for resistance, and flexibility at the hinge. Connective and structural proteins are up to all tasks but I’d love to have some detail. Can you get a big grant to do Coots’  feet? Unlikely – the prefix Nano seems to be absent – but we could live in hope.

Coots do look a bit odd, and we all know the “bald as a coot” phrase. Any slaphead should be thrilled to have the generous thick weave of a Coot’s breast, but that’s not the answer – it’s the white bit!

I was extremely fortunate to visit WWT Slimbridge recently and a pair of Coots caught my eye  – I guess I was in sniper mode and just hit them before I thought about it too much. There’s usually a video of anything you want on YouTube but the Coot courtship I can find is less intimate than this, and a bit squabbly. I’d prefer us to make our own narrative from the stills.

So a shorter post this time, and no homework –  I hope this is agreeable.

I have very early memories of Starlings; my mother would chop up bacon fat and put it out on the lawn and Starlings would arrive in seconds and jostle noisily over the food. Soon, bacon and birds were gone. I remembered them in black and white (like the television of the time), which is a meagre memory of a very striking bird. My recollection is dominated by their energy and combativeness, and by stories of their talents as mimics, something the BTO looked into a few years ago. As a member of the Young Ornithologists Club, I was interested in almost anything other than Starlings, a childish oversight. I mean, dammit, I wanted to see Avocets! When I started to become interested in birds again in my early twenties, the industrial landscape of south-west Lancashire provided me with a vivid Starling experience, but not a murmuration.

A few days before I was born, Princess Alexandra opened what I came to know (not entirely accurately) as the Runcorn Bridge, our version of the Sydney Harbour Bridge. It spans the Mersey and the Manchester Ship Canal, linking Widnes and Runcorn, and was a crucial part of our route for car journeys into  North Wales. If there are any Stone Roses fans reading this, Spike Island, the site of the now legendary performance, is not too far from the crossing. Chemical country started in earnest on the east bank of the Mersey, with several major ICI plants and research facilities. To the north-east of the crossing, in Cuerdley, lies the Fiddler’s Ferry power station, a 2000MW coal-fired power station, now decommissioned and set for demolition in 2023. The station still commands the skyline but when it was operational, the plumes of steam rising from the cooling towers were visible from a very considerable distance.

Many of my journeys to and from university involved Runcorn station where southbound trains could be boarded and we’d cross the Bridge, parallel to the railway crossing, often really quite stressed about the amount of traffic and wondering if the train could be caught or not. I’m not sure when we became aware of the Starlings; it might have been early one winter morning, or perhaps it was at dusk, but it was clear that there were very many starlings roosting on the huge arch. It seemed as if every inch of the steel bore a bird. The Wikipedia entry for the Bridge doesn’t mention it, but I’m sure there was a lot of grief back in the day about Starlings defecating on cars and corroding the steel.  Anyway, on evening journeys, light-permitting, we’d see the birds arriving, sometimes seeming to follow groups of birds in towards the Bridge. In the morning, small groups of birds would rise from the arch and head off to feed for the day. The size of the roost was astonishing and it makes sense (for me) of the scale of murmurations. I will do a crude calculation. The span of the Bridge was of the order of 300 m with a depth of about 10 m, so assuming an angle of arc of 180^o, that’s a surface area of (150 x 10 x pi) m² or ca. 4500 m². I’d like to assume that a Starling needs a roosting space of a cosy 5 cm x 5 cm, or 2.5 x 10^-3 m². If the actual area of the steel is 10% of the notional band surface of the bridge (450 m²) and they are packed in fully, the Bridge could accommodate ca. 2 x 10⁵ Starlings, which would make for a decent murmuration! I’d be happy to be within an order of magnitude of the numbers roosting on the Bridge. I looked up the UK population; the RSPB told me about population decline since the 1970s but failed to give me a number. The BTO gave me 1.8 million pairs. Maybe 2 x 10⁵ Starlings roosting on the Bridge is not unreasonable. Brodie writing in British Birds (J. Brodie, British Birds, 1976, 69, 51–⁠60) described some details of the behaviour of Starlings around a roost on the Forth Road Bridge, another magnificent steel structure. I stole this striking image from Brodie’s paper – I couldn’t find any details (is it a linocut?) or attribution and I’ll take it down if someone tells me off.

I’m very pleased to see Starlings these days – they seem far from commonplace. I appreciate the colours of the feathers now – they’re like a Thrush in colour negative mode.

I see them at the seaside – our usual haunts of Cardross, Irvine, Saltcoats, Stevenston and Troon. Murrays at Cardross offers them a safe perch from which to watch the foreshore; they swoop down and forage in the weed, into which they blend beautifully. My black and white from memory should really be of green and brown and iridescence. Rigging at Irvine is good perching too – who needs signal flags when you have Starlings? The blue abattoir roof at Saltcoats sets them off nicely, good colour contrast. They like the Sea Buckthorn too.

I have them watching from the Ballast Bank at Troon – there are some unpromising-looking wild swimmers out there and the Starlings are probably wondering if it’s worth sticking around in case there’s going to be some Ayrshire flesh washed up to peck at.  They’re assiduous bathers themselves and they’ve learned the trick of dropping snails from a height to get to the good stuff.

I like the way they seem to adapt to and decorate the human environment. I don’t think I’d like them in my loft or ravaging my fruit crop but I’m always cheered to see them. They are exquisite on the wing – I’d love to make the following image into a fabric, not that I’d be able to do anything with it.

There are about 400 Starlings in this image of a small group on the wing over Troon. I hope to see thousands together one day, making their extraordinary figure-of-eight shapes in the sky.

My best friend at junior school lived in a house with quite a big garden and together with his older brother, he used to simultaneously feed and torment a Robin. They had a knitted robin which they would mount on an old camera tripod set up in the middle of the lawn, close to a tray of mealworms. The Robin which had secured the territory would totally savage its apparent rival, usually knocking it off its perch and to the ground, where the assault would sometimes continue. Eventually, the knitted robin fell to pieces, the supply of mealworms was exhausted and the experiment ceased. Several experimental scientists-to-be were involved in these somewhat informal procedures, though I fear that our laboratory notebooks would not have withstood scrutiny and that the proposed experiments would have failed to secure ethical approval. Anyway, we’ll come back to Robin-based experiments later on.

Robins can absolutely be relied upon to perch nicely. The old signpost used to stand at the bottom of Geilston Lane, just above the high water mark at Cardross. The short walk from the rail station and sawmill to Murrays passes through at least half-a-dozen Robin territories; it’s very unusual to take this path without seeing several Robins, strung-out like shirt buttons along the path. I’ve never been aware of strife along the route even though territories are defended throughout the year, according to my RSPB book. I’ve rarely seen two together, but I do have this shot from beside the Kelvin.

A Robin has decided to hold a territory behind our house in Glasgow; the singing starts in the small hours and continues into the dusk. I’ve been recording it – here’s the extended remix, just over one hour in length. I think there are two birds competing at one stage, and you’ll hear some of our other regular visitors.

Robins are sedentary in some regions and migratory in others. I thought I knew that UK populations were boosted in winter by Robins from Central Europe but I struggled to find evidence for this in the primary literature, despite working hard with keywords and citation searches. I did find a piece in Country Living, of all places, from 2019. A “nanotagged” Robin flew in four hours from Heligoland to Felixstowe via Amsterdam under cover of darkness. Chris Hewson of the BTO had apparently spoken to The Times about these findings and I wrote to him, hoping that he would identify the relevant research publication. Alas, he didn’t. I did find some interesting BTO webpages on  tracking methods.

The tag used on the Robin weighed about 0.3 g, ca. 1.5% of the bodyweight of a 20 g Robin. That’s about the same relative loading as me running back home from Screwfix in Possil Park with a large box of Polyfilla, something I have been known to do, but not for hours, and not over water in the dark. I do sometimes wonder about the ethical calculations carried out in advance of tagging experiments. Still, as batteries get smaller and better, so do the tags. I was also intrigued by Country Living‘s use of the nano- prefix. Anyone with a science background knows that nano- is Greek for “Give me a large grant, now…”; more seriously, 0.3 g is more milli- than nano- (only a factor of 10⁶ out, then), but it would appear that devices are getting smaller and less significantly burdensome, particularly for the smaller birds. I’m glad the little chap landed in Felixstowe, rather than, say, Frinton-on-Sea; there are some nice people in Felixstowe (hello Ricard, if you’re reading), whereas the Brexiters of Frinton would have probably kebabed him.

I found an interesting piece about Robin migration which did not use tagging, not open access, alas, but I will give the reference (Catry et al., Oecologia, 2016, 182, 985–994). Because feathers, once fully developed, are metabolically inert, they reflect the environment in which they were grown. There seem to be consistent differences in the relative amounts of deuterium, hydrogen’s heavy stable isotope, within the feather protein (keratin) between birds from different locations. The team sampled feathers from a wide range of European locations and mapped them by isotope ratio, determined by mass spectrometry. This technique which effectively “weighs” molecular species to an astonishing level of precision, allows very small variations in hydrogen/deuterium ratios to be detected and quantified. Feather samples taken from migrant birds on the Iberian peninsula, a destination site for many birds from northern Europe were also examined. These isotope ratios could be used not only to assign the origins of Robins wintering on the peninsula, but also to reveal how the birds were organising themselves with respect to habitats and food sources. This technique sounds less invasive than tagging but the environment or habitat mapping is a lot of work! Of local interest, the mass spectrometry was carried out at NERC’s facility in East Kilbride which falls under Glasgow University’s umbrella, but has nothing attractive to offer in terms of a web presence, which is a pity.

The other research findings I wish to report sound like a bit of a torment (Lind et al., Behav. Ecol. Sociobiol., 1999, 46, 65-70, again, not an open access publication, alas). Robins were fed to different fuel loadings (this means their masses divided by their wing surface areas) and had a model Merlin launched at them to see if they could vary their angle of ascent in response to the approach trajectory of the predator, and if their weight had an effect on that angle. The answers seem to be “no” and “yes”, with the more fuelled-up Robins getting off less steeply. I thought the following text was quite interesting: “Robins are not forced to cross any extreme barriers, and they do not migrate as far. They may therefore travel with smaller fuel loads and thus be better able than, for example tropical migrants, to give priority to safety during migration. When the Robins arrive at the wintering area, they do in fact choose territories mainly for protection, and not for good feeding opportunities.”

The Robins I meet at my fishery definitely do not see me as a potential predator. I throw and catapult maggots into the pond, and I drop a good many so they’ll be crawling all around me after a while, and the Robins come right to my feet for them, taking great bundles away. Once they’ve tidied me up, it’s straight into the bait tray for the grubs or whatever else I have there. I haven’t managed to photograph this action – they’re a bit too close to me to be relaxed in front of the camera.

On one summer visit, I ended up feeding a shoal of big Ide in front of me and young Robins and Blackbirds (two of each) behind me, and I went through quite a bit of bait that day.

If anyone is interested, here’s a video of two of our most public-facing match anglers (Andy May and Jamie Hughes) catching Ide at a commercial fishery – the action starts around 7:45. Fish are caught during this video so please don’t watch if that’s likely to upset you.

Finally, the Christmas card department – who can resist Robins and snow. Not me. I’ve one from Frankfield Loch near Stepps and two images of the locals in Kelvingrove Park (including a “digital print”). Backwoodsman will post again on Saturday 4^th March, with any luck.

Backwoodsman has his eyes on the ground this week. We travelled to Bishopbriggs in late February 2022 and walked east along the Forth and Clyde Canal. The walk took us past Cadder Parish Church and an unexpected and spectacular display of Snowdrops in the churchyard.

We returned last Sunday, full of anticipation. I had seen Snowdrops coming through in my mother’s garden while I was shifting the autumn leaves, and we had both seen them on the banks of the Kelvin, so we were confident that Cadder would have a good show ready for us. We weren’t disappointed, and I set to work to try and take some nice photographs while the church was readied for the service at half-past ten. I made a recording of a Robin singing, backed by some distant Jackdaws, and the church pianist playing the hymn tune Laudate dominum by C. H. H. Parry.

“Pavillioned in splendour” indeed. I was extremely careful where I put my feet, scrutinising the ground before taking each step in case there were shoots still coming through the churchyard moss.

Nicola Chester writing in the RSPB Magazine (Winter/Spring 2023, page 14) introduced me to a new word – vernalisation. I autodefined this as a process of becoming springlike, based on the definition of vernal – of, in, or appropriate to spring. Well, there’s a bit more to it. The John Innes Centre put me right and I enjoyed two videos by Professor Dame Caroline Dean (a six minute version, and a longer lecture given at the Royal Institution). The process by which plants use a prolonged cold period – winter – to promote flowering is known as vernalisation. I won’t attempt to paraphrase the JIC’s lucid web page, or Dean’s excellent material but I will highlight the role of epigenetics in the response of plants to temperature. Dean spends some time explaining the meaning and importance of this relatively new field – it has important implications for human health too.

I had my usual poke around in the literature which deals with plants and cold weather; I suppose it’s a bit like gently turning over leaves at this time of year to see the spring bulbs and hellebores coming through, having survived the hard weather. I was prompted to investigate by the idea of antifreeze proteins which had cropped up in the RSPB article and in the JIC material.

I found this idea strongly contra-intuitive. The antifreeze that we used to add to the radiator water in a car is ethylene glycol, a very small molecule, by which I mean it has few atoms. It is highly soluble in water and disrupts the formation of the extended lattice structures upon which freezing depends by displacing water molecules from the networks of O-H…O hydrogen bonds, so that the water doesn’t freeze at its usual temperature. This depression of freezing point is known as a “colligative property”. I attempted to read a primary publication in this area by Marangoni et al., and a recent review by Kumar and co-workers and both are chastening reminders of the very specialised nature of modern science. Antifreeze proteins (AFPs) are enormous in comparison with water molecules and they function in a highly sophisticated and non-colligative way, offering sites upon which tiny developing ice crystals can sit, blocking their growth and suppressing the formation of bulk ice. I started worrying about the relative amounts of AFPs and water molecules in any plant cell and I’m still worried – I’d better read the pdfs again.

Though there are very authoritative descriptions of its three-dimensional structure from crystallographic studies, ice turns out to be trickier stuff than we thought. In the last few days, a collaboration between Cambridge and UCL has announced the discovery of a type of ice so novel that it may change the way we look at water itself.

It is only early February but the vernal aspect of the current days is hard to ignore with the snowdrops, the catkins beginning to open and birds asserting their territories. I’m hoping that the content of my post doesn’t bring a return of really cold weather. Our visit to Cadder Church coincided with the Snowdrop Spectacular Weeked at Newark Park in Gloucestershire, spectacular being the only way to describe the blooms at this NT property. It’s a few years since I was taken there but it was unforgettable. Snowdrops individually and in close up are exquisite but their appeal to me lies en masse and those are the images I leave you with.

The family Motacillidae has some charming members (as does the related Anthus, the Pipits). The Grey wagtail really makes an impact and it’s easy to get carried away by the flashes of intense colour. An excited post from April 2020 on NextDoor.com announced the presence of a Red-listed Yellow Wagtail on the Kelvin, providing a picture and confiding that it had flown all the way from Africa to see us. But the twitchers did not flock to Kelvinside – it was clearly a Grey wagtail which had been entertaining us all winter.

It doesn’t seem quite right that a bird blessed with such vibrant yellow plumage should be named for the colour of its head, but it is a very nice grey. What sort of yellow is that though? I’m somewhere between Lemon Cadmium and Deep Cadmium but I could be persuaded otherwise.

These are colours of Derwent Artist Pencils – I was given a big box of them when I was a child, and I was always particularly fond of the yellows and greens.

My best place to find Grey wagtails on the Kelvin is the section between Kelvinbridge and the Belmont Bridge – when the water level is normal (the Kelvin is currently a huge and very brown river), there are many bars, scrapes and ledges where the wagtails can forage. I also found them one January at RSPB Baron’s Haugh, quartering a flooded stock field. Grey wagtails are insectivorous and while there weren’t any insects on the wing to the human eye, the wagtails would probably be able to find anything that was present and snatch it.

I used to prefer BBC Radio 4’s Tweet of the Day when it had more bird and less Homo sapiens. I quite like the old birdsong records where the relevant track would begin “The grey wagtail, the grey wagtail…(nicely intoned by a chap in a dinner jacket) followed by a good blast of song and no more human input until the announcement of the next species. Alas, there is a lot of chat on Tweet of the Day. To be fair, the Grey wagtail episode presenter conveys a fantastic amount of information in ninety seconds but I’d much rather just hear the bird.

One interesting point made is that Grey wagtails can take to the streets in winter, abandoning the stream bed for an entirely different kind of wet rock. Our walk to work along Renfrew Street back in the day used to take us past the Glasgow School of Art and we would see a Grey wagtail between the student bar and the library, which faced each other across Scott Street. In honour of the GSA, here is my digital print of a Grey wagtail.

Grey wagtails don’t seem to need pristine environments; the River Douglas in Wigan is not exactly a crystal torrent but I enjoyed finding a Grey wagtail there early one very cold morning when I was killing time waiting for the Avanti to come and take me north from Wigan North Western station. The TotD presenter (I’m trying really hard not to name him but I can’t help myself, it’s Kwiss, my least favourite nature broadcaster giving it full-on sixth form drama enunciation) also enthuses about the elegant flight of the Grey wagtail – spot on Kwiss. It’s really only in the dipping flight and landing that the fan-like tail is unpacked for your appreciation.

It really is a thing of beauty – once the bird has landed, those long tail feathers are put away and it’s back to the tail flicking. I read something quite surprising about the flight patterns of migrating Grey wagtails; Sharrock writing in British Birds in 1964 tells us that ” Grey Wagtails are mainly diurnal migrants, generally flying at a height of under eighty feet; indeed, [it was] found that most fly at a height of five to thirty feet”. Migration across the sea (some Grey wagtails make quite long journeys) on a dipping flight, skimming the waves? Sounds pretty hazardous for a small bird.

It’s hard to tell if this is a breeding pair perching and calling because we’ve only the back view of one of the birds and we need to see the throats of both.  The image (slightly grainy but long range) was taken in early March. Let’s assume that it was a breeding pair – by the end of June, we found a young Grey wagtail being fed by the male on a rock mid-river a few metres upstream.

Upriver near the weir at Maryhill, we found a bird perched in a tree and singing, something that occurs close to the nest site.

Much further down the Kelvin, we found a male gathering insects and probably servicing a nest in the tall stone wall which confines the Kelvin’s north bank close to Benalder Street bridge.

An interesting visit this one – a large and loud youth accused me of taking photographs of HMS Glasgow, the Type 26 frigate then under construction at BAE in Govan, for the Russians. Little did he know that I had been after something far more beautiful and worthwhile.

I went to RSPB Baron’s Haugh on Tuesday on the hunt for Lapwings. The reserve page recommends late summer/autumn for finding them in large numbers but I had seen them from the Causeway hide on a winter day when the wetland was frozen so I fancied my chances. Everything was frozen hard – the wetland and all the surrounding vegetation. The causeway to the hide was under water, vegetation and ice and I did not fancy wet feet, but I didn’t miss anything from the hide. All the birds were right in the middle of the wetland, about as far as they could be from any vantage points. So while I enjoyed the beautiful light,  and the explosive sounds of the ice cracking, I thought about another frozen place where the birds were easier to see and photograph.

Frozen water can be hazardous for swans. We were at Hogganfield Loch on January 3^rd, 2021 when a swan rescue took place – it attracted many onlookers and the ice cream van did a roaring trade. Most of the images in this post were taken at the Loch on cold mornings in happier times, before the current outbreak of avian ‘flu, with the swans making some beautiful shapes.

The Loch is shallow and very weedy and it sustains a wide range of species. The Mutes and Whoopers get well fed on a regular basis, mostly with bread. When they’re not inundated with “Orange Warbies” (one of the great fishing baits, though many anglers prefer the blue version), swans are hugely inefficient processers of aquatic vegetation and inadvertent consumers of small creatures which get dragged up with the plants. Mark Nicolaides’ Swanlife website (which has some wonderful images) tells me that: “It has been suggested that for a Mute Swan feeding off wet vegetation, it could eat in excess of 3.5kg per day – which equates to about 30 to 35% of its body mass.”

A study (Li et al., PloS ONE 2022, 17(2): e0264528) of a population of Whooper Swans on a migration site on the Yellow River wetland in China, found that the birds derived a significant proportion of their energy intake from corn remaining on flooded unharvested farmland. A large team looked at both ends of the pipe; food material was burnt in calorimeters to allow accurate measurement of the energy yield of the various plant species available for the birds to graze. The researchers drawing the short straw (as it were), collected swan crap, dried it, suspended the residue in water and not only identified leaves and seeds using optical microscopy, but quantified the proportions of the different species in the matrix. OMG. The smarter research students probably offered bribes to ensure that they were assigned the former task.

When the birds couldn’t get corn, much of their food value came from the Common Reed (Phragmites australis). If they were Mute swans on the Forth and Clyde Canal, they would probably be munching Canadian Pond Weed (Elodea canadensis) though in insufficient quantities – the weed renders the waterway unfishable throughout most of the year (at least on the City Branch). I also have photographs from two Wildfowl and Wetlands Trust reserves; I visited Martin Mere in Lancashire in 2018 and Caerlaverock in Dumfries and Galloway on a dark January day in 2019. The peaceful Whoopers (above) are from the former site, while the mass feeding is from the latter (the punters behind the glass look transported). The mass feeding in Glasgow (below) was photographed on a glittering winter day.

I will revisit Mute swans in a different season when they offer something quite different. By then, the Whooper family groups will be back in Iceland if they have survived the ‘flu and packed on enough fat to sustain them on the journey.

Swans seem to bring out the worst in poets and Greek mythology involving swans is very dangerous ground, but I am aware of one restrained treatment. In The Death of Cygnus, Ted Hughes describes the slaughter of the son of Neptune by Achilles outside the walls of Troy. Five pages of ultra-violence takes us to the finale:

In those moments
Neptune’s words had breathed in off the ocean
And carried away Cygnus
On white wings, their each wingstroke
Yelping strangely – a bird with a long
Undulating neck and a bruised beak
Aimed at a land far beyond the horizon.

Form, sound and purpose elegantly brought to mind.