Sweden - a tale of three twitches

The Wilson's Snipe twitch

A few weeks back I mentioned to Ben Sheldon the possibility of organising a Sweden trip. This had been on the cards for a while - Ben frequently visits and is quite keen on his Swedish list, and a previous plan earlier in the year had fallen through. This time, I was gripped by reports of a displaying Wilson's Snipe in a relatively accessible part of Sweden. For some reason I found the idea of an American Snipe taking up residence in a Scandinavian forest, at a time of year where it never gets properly dark, really enticing. In Britain, Wilson's Snipe has exclusively been recorded on the Scillies in autumn/winter, where close views and increased observer awareness has resulted in a series of records supported by photo evidence. It is still a tricky identification, and in my opinion not the "best" way to experience the species. The display flight of Wilson's is distinct from Common Snipe, with the birds drumming using four outermost tail feathers rather than just two - producing a sound that is rarely heard in the Western Palearctic.

With a supporting cast of lingering rarities, including Dalmatian Pelican (first for Sweden), Blue-winged Teal, and Ring-billed Gull, together with the chance to see northern specialities such as Great Grey Owl and singing Blyth's Reed Warbler, it was clear that this was the perfect time to visit. I was also keen to study some Baltic Gulls in their core range, which would be a first for me after my attempts to identify them in Britain.

This will be a rather different blog post to usual, because I don't have many photos of birds to show. Unfortunately, my Olympus kit is currently being repaired after the lens mount sheared off. Seemingly many small knocks have taken their toll - the lens had had a bit of lateral play for a while and as I was taking it out of my bag it completely fell apart. I did bring my old Canon 7d Mark II and 400mm f/5.6 but to be honest  I wasn't particularly motivated to use it. In any case, at least you've all been spared another fuscus photo gallery/essay...

We flew from Heathrow to Stockholm Arlanda late evening on Sunday 6th July, and after an uneventful journey we settled into our accommodation in Uppsala in preparation for an early start on Monday morning.

A fantastic sunset from the balcony of the house

Our first stop was Hjälstaviken, a large lake southwest of Uppsala which is a well-known site for migrating waders and wildfowl. Amongst the many Wood Sandpipers were our only Curlew Sandpipers of the trip (a flock of five), and sitting in the Black-headed Gull colony were two Caspian Terns. On the way back to the car we had a nice view of a Lesser Spotted Woodpecker. We then drove to Frövisjön, where the Blue-winged Teal was currently summering. Breeding Goldeneye and Little Gull were good to see, whilst a couple of Spotted Redshank and Ruff were the best of the migrant waders. The duck was nowhere to be seen, however - it was apparently favouring an area of reeds around a large bush, and was out in the open only sporadically. Other twitchers on site reported some people having to wait six hours to see the bird! We spend a while half-heartedly grilling a couple of mostly obscured birds, before we had to move on - although as the site was relatively close by, we planned to return the following day.

View over Hjälstaviken from the tower - quite typical of Scandinavian nature reserves, which favour these viewing platforms over hides. I'd like to see more of them in the UK!

After stopping for some snacks, we began the drive through Uppland to our main target for today, the Dalmatian Pelican. The bird had been roaming widely between Sweden and Finland since being found, but had luckily settled down a bit by the time our trip rolled round, and was frequenting the island of Orarna, which is a nature reserve with no public access. There were a few points on the mainland from which people had been seeing the Pelican, and we were encouraged by recent update on its location as we drove north.

We pulled up at the suggested viewpoint and couldn't immediately see where to start searching - rather than the vista we expected, we were looking at a narrow strip of water between the mainland and Orarna. There was no sign of the Pelican, nor any twitchers. Continuing along the path, we soon encountered a large group of birders scoping something. Glancing briefly in the direction they were viewing, I could see a distant white shape through bins - this was surely the bird. I set my scope on it and you can imagine my disappointment when I realised that it was a Mute Swan! It transpired that the Pelican had only been seen briefly in flight earlier, before being lost to view somewhere in the reedy inlets surrounding the island. The positioning of the group of twitchers was very odd, standing about 20 metres back from what was a much better viewpoint right next to the shore, where a gap in the trees allowed you to see over the water. Standing where we were, there was only tiny field of view to look for the Pelican. We daren't question this strange decision - perhaps this is how twitches are done in Sweden - so waited for a while before deciding that this was obviously futile. A flyover Osprey salvaged the stop.

We spent the afternoon visiting a few other sites in the area with Joe Wynn, who was also in Sweden for fieldwork. The bay at Ledskärsbryggan had hosted Pacific Golden Plover in the last week, but we had no luck searching amongst the Lapwings - however, an Icterine Warbler calling from the car park bushes was a welcome addition. Looking out over the Baltic Sea at Rödhäll, we picked up a few more ticks - Red-breasted Merganser, Goosander, Eider, Black Guillemot, and two Arctic Skuas mobbing a White-tailed Eagle. I also had my first views of Baltic Gull, very distantly on one of their colony islands (where Joe had been ringing earlier in the day). Apparently they are quite pelagic compared to other gulls and their colony sizes are rather small - typically only a few pairs. A Hobby flying far out over the sea was another oddity. We unsuccessfully tried twitching a Citrine Wagtail at Södra Vendelsjön, with the only birds of note being a flock of Black Terns over the lake.

News that the Pelican was roosting back on its favourite rock meant that we had to give it another go. We pulled up next to the pier at Lutens Väg and joined a few other birders already present. Here we had a nice view across the bay to Orarna, but the island was so distant I was wondering how on earth we would be able to identify the bird. Measuring on Google maps, we were around 4km away from the shoreline! The instructions given were brief and unenthusiastic - left of the left turbine, on the white rock. I couldn't see anything through bins. Cranking up the scope, I was able make out a few birds on the island. I could see a large white rock, and realised that the top half of the rock was in fact a perched white bird, completely tucked up. I panned over to compare its size with a Mute Swan, and confirmed that the blob was substantially bigger. We also noted the tuft of feathers at the back of its head, visible even though it had its bill hidden. Enough to confirm that this was indeed the Dalmatian Pelican (or at the very least a Pelican), although possibly the most unsatisfying world tick ever. We waited for a while to see if it would reveal its head, but no luck. We read later that the bird had been chased off of its perch by White-tailed Eagles - now that would have been quite something to see! We called it a day and headed back to Uppsala.

The Dalmatian Pelican on its favourite rock, with Cormorants to the right. Video below showing how far we had to zoom in!

Another early start the next morning for a singing Blyth's Reed Warbler fairly near to our accommodation. The bird showed surprisingly well, although its proximity to the road meant that my recordings are quite noisy. It is amazing how far the sound of a car travels! A lifer for me and a bird that I hope to see/find in Britain soon. A stop at a newly-created wetland produced excellent views of Red-necked and Slavonian Grebe on territory, before we headed into Stockholm.

Our main target here was a summering Ring-billed Gull, as well as the opportunity to observe Baltic Gulls at close range. An added bonus was the fact that Lars Jonsson's Invisibilis exhibition is currently running at the  Liljevalchs Art Gallery - a must-see for any birder visiting Stockholm. We parked the car just around the corner from the Ring-billed Gull site, which turned out to be an ornamental pond and fountain in the middle of a city square - completely bizarre. There were a few Black-headed and Common Gulls milling around, although no sign of the bird, so we decided to get some food and wait. I of course offered a few scraps to the birds, and soon a nice adult Baltic Gull flew down and practically ate out of my hand, before deciding to steal Ben's cinnamon bun - fantastic. I also briefly saw a couple of 3cy fuscus, and I was pleased to see that these looked very similar to the candidate bird I had at Stanton St John in May - complete with advanced mantle/tail moult. Apparently, 2cy birds are quite uncommon in Sweden, with most summering further south.

Just as we were getting up to leave, the Ring-billed Gull flew in, instantly recognisable in flight even from a distance. Initially it perched up on the roof of a nearby cafe, although another cinnamon bun was enough to tempt it down. Clearly the bird is very used to people, and by this point we had been joined by a couple of other twitchers, who enjoyed seeing us feeding it at close range. This video illustrates just how well it showed - useless trying to use my DSLR most of the time, as the 400mm focal length was far too long to fit the whole bird in the frame. I chose to enjoy it mostly without optics, which also seemed more apt in a city centre setting.

We headed over to the gallery, taking in Stockholm's small population of Barnacle Geese - apparently derived both from escaped stock and natural colonisation. I was absolutely blown away by the exhibition, having previously seen many of the paintings in books/online. In life, I was taken by his use of negative space when painting winter scenes using watercolour (not immediately apparent when just viewing images), and the large format of his work. There was a mixture of watercolour field sketches, fine art oils and field guide plates spread across several large rooms - Jonsson is clearly a much-loved artist in Sweden to have commanded such an extensive exhibition. The highlight for me was a piece called "Evolution", a wall of 300 gull field sketches from across the globe (and, bizarrely, one spoonbill - perhaps some artistic humour). Somewhat overwhelming to experience rare gulls and the art of Lars Jonsson in the space of just a few hours. I only wish I had had more time to spend at the exhibition, as I think I could have spent an entire day there.

We were on a tight schedule, however, with the plan being to connect with Wilson's Snipe that evening, so we had one last look at the Ring-billed Gull before heading out of the city. We had another session dipping the Blue-winged Teal on our drive west. The views changed from the flat, semi-agricultural land surrounding Stockholm to more hilly, forested and undeniably wilder looking landscapes as we approached the site. After around three hours we turned north along a gravel track into the forest - we had arrived. Apart from a couple of houses along the track, the place was deserted. A pair of Black Woodpeckers called as we got out of the car and headed into the forest.

The Wilson's Snipe had not been seen the previous day, although we chalked this up to sporadic visits from twitchers now that it had been on territory for a while. According to reports, the bird was reliably displaying around 8pm, so we had arrived right on time. We walked a short distance through the trees towards a more open area, and the ground became increasingly boggy. After around 20 minutes waiting, we couldn't hear or see any Snipe at all - whether Common or Wilson's - so we were getting a bit confused. Displaying birds should be audible from quite far away. There was also no sign of the tree stumps that the bird had been favouring and it all looked pretty overgrown. Surely this couldn't be right - I checked the map with Ben and it became apparent that the last person to upload a sighting of the bird had dropped the map pin in the wrong place! All of the previous drop pins were from another area of clearfell a few hundred metres away, and grumbling, we made our way back along the path, shoes full of water.

Pulling in at the correct layby (which already had a birder's car parked in it), we followed a well-trodden path leading away along the edge of a field. Rounding a corner, a somewhat post-apocalytic landscape stretched away in front of us, full of smashed trees and stagnant puddles. In the middle of this scene were two figures and a scope, solemnly facing the setting sun. We hurried towards our fellow twitchers and enquired about the Wilson's Snipe. They had arrived a short while previously and confirmed that the bird was still present - it had perched briefly on its favourite stump before being chased away by a Common Snipe. We had missed it by minutes, so we were gripped. If we hadn't wasted half an hour at the wrong location, we would have already seen it! In true Swedish fashion, they calmly assured us that it would soon return and begin displaying.

Feeling slightly more optimistic, I set my scope on the perch and began waiting. Despite the logging destruction the atmosphere of the place was phenomenal. Woodcocks were roding overhead, Cranes bugled unseen from beyond the clearfell and a flock of Swifts were hunting insects in the dying light. A Great Grey Shrike perched up on one of the firs behind us - a nice Swedish tick.

The attitude to twitching in Sweden seems very different to the UK. Both of our companions were not just patiently waiting for the bird, but actively searching rather than chatting loudly or sitting idly on their phones. In fact there was a silently focused, serene, almost druidic air to the twitch. One guy was laden with every piece of gear you could possibly need - bins, scope, camera, parabolic microphone, thermal imager, mosquito thermacell, all neatly arranged in camo pouches. Every so often he would scan the parabolic microphone with headphones in, listening for distant signs of the bird. I have never been more impressed.

Ben Sheldon, Jens Morin and Son(?)

Mist rolled in across the clearing, and the bird's favourite perches were soon obscured. A Redwing called overhead. It was getting cold and damp and there was still no sign of the bird. Ben returned to the car to get more clothing and had a brief sighting of a moose - gripped! It was now as dark as it was going to get that night, although the sky was still pale and clear. Despite the mist and setting sun, bird activity was increasing. These were probably my best ever views of Woodcocks roding, and I distracted myself with taking some sound recordings. A fantastic ambience.

Despite this Ben was somewhat despairing at the bird's absence - "I can't believe we're here on the one night it isn't displaying!". I told him that we had only been waiting 90 minutes and was willing to stay here all night until we connected. Despite this, I worried that he was becoming silently inconsolable - at one point I glanced over and he was looking at the ground, shaking his head. I wondered what I would say on the three-and-a-half-hour drive back if we dipped, especially as we had arguably twitched this bird all the way from Britain!

The mid-twitch dip in mood

Eventually, our Swedish friend detected something through the parabolic microphone. Straining my ears, I could just about hear a Snipe calling a few hundred metres away. He confirmed that it was a Common Snipe, but that this mirrored what happened when the Wilson's Snipe last showed, with other birds encouraging it to start displaying. "It is a good sign" he said, with a slight smile. After a few minutes he said that he thought he could hear the Wilson's Snipe calling as well. I wasn't familiar with the differences in the chip calls so was struggling a bit. He said that it had called a couple of times before and that the chip was slightly harsher sounding. I thought I could hear a different rhythm as well, but to be honest wasn't sure if what I was picking up was variations in Common Snipe. "We need more than this" said Ben.

The sound stopped for a couple of minutes and I saw a Snipe fly low across the clearing right in front of us - it looked a bit odd, rather short-billed, and I wondered it that could have been the Wilson's Snipe, although the light was really gone by this point. Surely enough, birds began calling again from a stack of trees much closer to us - seemingly a mixture of Common and Wilson's type vocalisations, and I was beginning to appreciate the differences a bit more. I've attached a sound recording below, of what I believe to be a Common Snipe followed by Wilson's Snipe calling, potentially with a brief duet at the end, although after looking through Xeno-canto I'm not 100% sure of the extent of variation and this could well just be one bird. If anyone reading has any insights please let me know - apparently an article on the differences in vocalisations is being prepared for the Swedish birding magazine, based on recordings from this bird.

What we really needed now was some drumming - proper display flight. We only had to wait a few minutes more before that haunting sound floated over the tops of the trees towards us. So different to Common Snipe - higher pitched, slower paced, sounding less "mechanical" and more like some strange winnowing owl. Despite the fact that the bird was presumably right over our heads, it offered only the faintest of glimpses during its display - I assume it was way up high and the light was too dim for us to resolve it properly. One of the Swedish birders said he could make it out as a dot whizzing around through the thermal imager. Still, the sound was what I had mostly come for, and the fact that we could barely see it somehow made the experience even more ethereal. Volume up for the video!

The Wilson's Snipe was displaying over this clearing - Woodcock also audible in the recording below

We listened to the Wilson's Snipe for around half an hour before heading back to the car, conscious that we still had to drive through the night to get back to Uppsala. We were both completely exhausted, almost turning onto the wrong side of the motorway as we left the forest tracks. An arduous journey followed, with the road being temporarily closed for resurfacing before we were randomly stopped by police. I was not expecting my first breathalysing experience to be at 2am in Sweden after twitching an American wader! I was most concerned about whether they were going to ask me to get out of the car, because it would have then become obvious that I wasn't wearing any shoes - they had got so sodden in the bog that I couldn't face driving in them for hours. I can't imagine that the police would have been impressed! Eventually we made it back to Uppsala and watched the sun rise again at 02:45am. What a phenomenal experience.

After a couple of hours sleep, we spent the morning of the third and final day checking out a few local sites, including some woodland and reedbed that we had previously neglected. Another visit to the scrapes at Hjälstaviken yielded two Temminck's Stints, a pair of Honey Buzzards were soaring over the woods behind, and juvenile Bearded Tits pinged in the reedbed. We stopped for another hour to dip the Blue-winged Teal for the last time before accepting that it wasn't to be. Despite being reported by other birders each day of our trip, somehow we were unable to connect with this bird - although if I had to choose which of our targets to miss in Sweden it would surely be the Blue-winged Teal, so not too bad going. Only downside was the amount of time spent staring at that bush!

We returned to Uppsala, taking in Ben's old patch (where he famously found Sweden's second Slender-billed Gull) before meeting up with Per Alström, who kindly provided lunch. After three days of service station food and bits of bread, we responded to the paneer curry laid out before us like sailors coming ashore after a season at sea! Per had agreed to show us some local sites for Great Grey Owl which had been found by Bo Söderström, who specialises in sound recording in these forests (link to his extraordinary SoundCloud here). In the interests of keeping the locations hidden I'll let these photos do the talking, in lieu of providing a detailed description. I realise that I've let the superlatives flow freely throughout this blog post, but honestly these were just amazing birds.

We found the juvenile first, which was already very impressive (although I must admit thinking that it wasn't quite as large as I imagined). This was then completely eclipsed by the adult sitting a few trees away, both in size and aura. The bird was almost completely unconcerned by our presence, often turning its back to us and continuing to doze. At one point it spread its wings and flew a short distance - it must be incredible to see them hunting.

We also picked up a few other forest specialities, such as Capercaillie, Crested Tit and Tree Pipit, but dipped Ural Owl at a different site in the forest. Unfortunately, it was a bit too late in the season to try for owls in nestboxes, such as Tengmalm's and Pygmy. By this point we were completely exhausted so bailed on attempting to see Nightjar, especially as we had an early flight back the following morning. We finished on 131 species across the three days.

Ben Sheldon and Per Alström

Overall my impression of Sweden was very positive, despite the severe lack of sleep during this trip (from which I think I am still recovering!). The country and cities were beautiful, the reserves quiet and full of birds, whilst the birders themselves were a breath of fresh air compared to the British scene. It was good to intersperse some twitches throughout, despite the fact that we would have probably seen more if we had focused on seeing all available residents and migrants to pad out the Swedish list. I just think it  made the trip more interesting and targeted. The Wilson's Snipe has got to be a contender for best twitch ever - the distance travelled, the ambience of the location, the behaviour of the bird and of course the jeopardy of potentially dipping. It really felt like a bit of an adventure! I don't think that this twitch will be the start of a Western Palearctic listing obsession but I can certainly see myself organising future trips around rare birds rather than just general birding. Having been to Lithuania as well last year, I can firmly say that the area around the Baltic Sea is one of my favourite parts of Europe.

Many thanks to Ben for sorting the logistics and accommodation for this trip, as well as Per and Bo for their hospitality on the last day. A link to our eBird trip report can be found here.

A perplexing gull

As a starter, note the pristine white tips to the inner primaries - surely these would be far more worn if the primaries were a year old...

I've not updated the blog for a while and my next post was going to be a summary of the rather exciting birding that I've experienced over the past month - however, I feel like it's worth getting another gull essay out of the way first. The header image perfectly sums up the absolute headache in aging this Lesser Black-backed Gull at Stanton St John on 15th June. In my submission to the BBRC for the four Baltic Gulls from Appleford in 2021 I said something along the lines of "the biggest confusion when identifying 2cy fuscus is not 2cy intermedius/graellsii, but 3cy intermedius/graellsii". It seems that I may have potentially fallen for this trap myself, although I suspect this particular bird will continue to defy any attempts at identification!

The water level at Shepherd's Pits has been slowly going down over the past couple of weeks and it is now looking very attractive to waders. Being only five minutes from my house I can quickly check it on my way to and from other sites, and I've been monitoring a pair of Little Ringed Plovers that arrived a few days ago. I initially thought these must be failed breeders and were surely early migrants about to head off - but they've taken a liking to the pit and have offered some great photographic opportunities.

There were only a handful of gulls present so there seemed little point in hanging around. I was just about to leave when I saw a new gull flying in from the east, heading directly towards me. For some reason it gave off a curious impression and even some alarm bells for heuglini began ringing - I could see that the wing was fairly dark and fresh whilst the upperparts seemed paler than what I would expect for fuscus. I took a series of photos as it flew around the pit a few times before settling on the small mound in the middle next to a 3cy graellsii Lesser Black-backed Gull.

I got the scope out of the boot of the car and the bird was close enough to obtain detailed views. Now that it was on the deck it seemed much more like a fuscus, at least in terms of its attenuated structure, moulting white head with a thin, insipid-coloured, black-tipped bill and dark eye - although I couldn't get past the fact that the mantle was much too pale. Not only was it pale, but the base colour of the feathers was slaty-grey rather than brownish - lighter, in fact, than the 3cy graellsii next to it. I could see that most of the visible scapulars were bleached second-generation feathers with broad white fringes (apart from maybe a few in the middle of the mantle between the wings, visible in flight), and wondered if that could be an explanation. Indeed, if some dark third-generation feathers were beginning to come through I wouldn't have questioned my identification. The second-generation scapular and covert pattern (with a single dark line down the middle of the feather, lacking any anchor markings) is most typical of fuscus and intermedius although can sometimes be found in graellsii.

The primaries seemed blacker and fresher when compared with the 3cy next to it, and looking through the photos on the back of my camera confirmed my thoughts that these were definitely second-generation primaries, being dark and rounded. In fact, they were in great condition, with pristine white tips on some of the inner primaries. I also noted that P1 had been shed, and thus the bird was starting its third wave of primary moult. Bizarrely, there were only eight primaries present on the left wing compared with the right wing, and although the images are difficult to interpret, I'm pretty certain this is because P10 was missing on the left wing. The gap in the inner primaries where P1 was shed didn't seem to be larger on the left wing compared with the right wing, and P10 usually appears a tiny bit shorter than P9 on an extended wing, which can be seen in the right wing but not the left. All secondaries and tail feathers were moulted to second-generation, and the tail did not have any white third-generation feathers (often found in 3cy intermedius/graellsii). The underwing was whitish but not completely white - a feature that is variable in fuscus. I knew that pale fuscus can be found in the core range so if the moult was right I didn't see this as too much of a problem, so I decided to put the news out as a Baltic Gull on the local WhatsApp group - although I was still doubting myself a bit.

Digiscoped image showing a little more detail - including some fine streaking on the neck that is being moulted out

I continued watching the bird (which wasn't doing very much) and Tom Bedford soon arrived on his bike. I got him onto the bird but I was beginning to feel more concerned and voiced that the mantle was too pale. I was also beginning to wonder if my aging was correct. After just a few minutes it took off with its graellsii companion and flew southwest. We waited a while in case it returned and observed the Little Ringed Plovers displaying and copulating, but there's been no further sign of the gull - thanks to Justin and Lew for checking.

I find birds like this very interesting but they invariably cause me to waste a lot of time searching through hundreds of gull photos online. At the end of my research I'm barely the wiser about this bird, but will attempt to summarise my thoughts. Since the identification of fuscus hinges on accurate aging, this is the main area I will try and address.

Other than the bare-part colouration, dark eye and mantle condition (all of which indicate a 2cy), two things stand out to me when trying to age this bird - the state of wear in the primaries and the timing of the third moult wave. In the field, I had judged the primaries and secondaries to be in a very good condition compared with the 3cy bird next to it (as well as my experience with watching a lot of 3cy individuals recently, most of which have had obviously worn, brown second-generation primaries), but on reflection, I do wonder if the fresh primaries of a 2cy fuscus would appear even blacker and more distinct, although assessing this in harsh sunlight can be a real pain. This feature is also variable depending on exactly when a 2cy fuscus replaces its primaries, but we might expect these to be up to six months old if that were the case. In the flight photographs, the primaries don't show too much wear or bleaching, but there are small areas of damage evident on some of the feathers, and maybe a slight brownish cast. Overall, the condition of the primaries is basically in between what I would expect a typical 2cy fuscus and 3cy intermedius/graellsii to look like - distinctive, but not blindingly fresh. I can find images of both 2cy fuscus and 3cy intermedius/graellsii where the condition of the primaries match this bird.

Crop from an image above - of course a comparison between only two birds is probably of limited value, but illustrates the difference in primary condition between the odd gull (front) and the 3cy graellsii (behind), in which the feathers are considerably more worn, brown and frayed

The dropped P1 indicates that the third wave of primary moult has just started. This is very early for fuscus - I have found photos of a few individuals like this in mid-June, but usually they begin moulting in July or August. In contrast, the timing fits well with a 3cy graellsii/intermedius starting its third wave of primary moult. I find it hard to reconcile the severely retarded mantle moult of this bird with comparatively advanced wing moult, if it is indeed a fuscus - although I guess stranger things have happened. I think these two features combined are possibly more supportive of a 3cy rather than a 2cy, although I really don't think those primaries look a year old (as they should be on a 3cy graellsii/intermedius). I have never seen a 3cy bird like this and have failed to find any images of one that matches its overall appearance either. It must have a hormonal deficiency for the bare parts to be so dull at this age, and the upperparts basically look like a 2cy intermedius. Almost all 3cy graellsii/intermedius will have replaced at least some of the scapulars and coverts with plain third-generation feathers at this point.

The alternative explanation is an unusually pale 2cy fuscus or an intergrade with intermedius from one of the mixed colonies in Norway, which could explain both the colour and weird moult. Pale birds are not too infrequent in the core range and matters there are complicated by heuglini. In Western Europe, however, I doubt these pale birds are acceptable as vagrants by rarities committees. I also don't see much here to support an identification as heuglini other than the mantle colour - I don't think I can really make a case for multiple moult loci within the primaries based on a missing P10 on one wing. Whilst heuglini can follow an accelerated primary moult strategy like fuscus, I think it is more likely to show a very advanced mantle (with lots of blue-grey third-generation feathers) combined with retained juvenile primaries - i.e. the opposite of what we are seeing in this bird.

Based on all of these conflicting factors, I've decided that it's best to leave this bird unaged and therefore unidentified - I apologise to Tom for his efforts in twitching it! I definitely think it would be rejected if I submitted it as a Baltic Gull, purely based on being too pale. To be honest, whatever it is, there is clearly something weird going on with this bird, both in terms of its moult and its colour - the whole plumage just looks kind of grey and washed out (in direct comparison with the 3cy graellsii, for example, it clearly lacks the brown tones found on the worn coverts), and I wonder whether this indicates some sort of underlying pigment abnormality.

So overall, a frustrating but educational bird, and illustrates the problem with fuscus identification when only assessing moult in the absence of other crucial features, such as the very dark mantle feathers. Recognising a Baltic Gull through accelerated moult requires accurate aging, as the whole point is that a 2cy fuscus is advanced enough to look like a 3cy graellsii/intermedius. I would welcome any thoughts on this bird and in the meantime I will continue looking.

Two nice finds

Northern Cross Valley Way

As soon as I've abandoned the patch it seems that I've begun finding birds again. Northern Cross Valley Way (a new site near Witney) has been attracting a run of good waders recently, including two Avocets on 26th April. I dipped these birds the next day and was pretty gripped by the potential of the site. It looks a lot like Appleford in its heyday, before it became overgrown - muddy scrapes just looking absolutely perfect for waders, all easily viewable from a raised bund overlooking the pit. This complex of lakes is also the first big area of water going west-east after the Cotswold Water Park, which no doubt helps to pull birds down as they migrate overland from the Severn to the North Sea.

On 4th May I arrived early in the morning and could see some small waders through bins on the far side of the pit. Setting up the scope, I began panning through them - Ringed Plover, Ringed Plover, Ringed Plover... Temminck's Stint. Nice. I'll admit I let out a little cheer. A self-found tick for me and only the second I've seen in the county after a frustratingly distant bird on Otmoor in 2017. It's a rather scarce bird in the county (last records being short-stayers in 2023 and 2018) and it's been a quiet spring, so unsurprisingly it generated a bit of a twitch - I think at least 30 people saw it throughout the day.

Initial distant views of the Temminck's Stint with a Ringed Plover, digiscoped at 60x magnification and heavily cropped!

First responders - Adam digiscoping at the front, courtesy of Justin Taylor

The bird then flew to the central spit and gradually moved closer, offering pretty good scope views as it crept around feeding. Still too distant for the camera even with the 2x extender, although I eventually managed to get this digiscoped image which I was happy with. After I left it apparently disappeared for a bit and was much harder to see amongst vegetation at the eastern end of the pit in worsening light as the day progressed.

Having been slightly rejuvenated by this find after a terrible effort/reward ratio over the past few months, I've been enjoying local birding a little bit more. I found a Black Tern at Appleford whilst doing a casual county day list by bike (not really a serious big day attempt - managed 104 birds and cycled ~150km) and enjoyed a couple of female Blue-headed Wagtails - sadly no males, nor rarer subspecies for me this year so far. I've also been making an effort to take more photos of common birds on my walks around Otmoor and Farmoor.

Black Tern, Appleford New Workings - the first in the county this year

Female Blue-headed Wagtail at Noke Farm, Otmoor

Note clear demarcation between olive mantle and blue-grey head, as well as pure white supercilium and throat

With a female flavissima

Barn Owl, Otmoor

Bittern, Otmoor

Marsh Harrier, Otmoor

Amazing light that evening but had to use high ISO levels!

Swift, Farmoor

Yellow Wagtail, Stanton St John

Gulls have been rather irregular at Stanton St John this year but given that it's only five minutes from my house I've been making sure to drive past and check it quite regularly. Early morning on 8th May I was pleased to see a large group of gulls swimming in the water and loafing around the edge of Shepherd's Pits - clearly having roosted the night before. Immediately I saw a nice 2cy Caspian Gull which is clearly different to the lingering Farmoor individual - a good bird in Oxfordshire in May.

The pictures below are the Farmoor bird for comparison - it's been around for quite a while and has now started its primary moult. A similar-looking hybrid has also been present and is causing some confusion!

Having checked most of the gulls on the water, I began searching through the more distant flock loafing around the field margins. There was a partially obscured Lesser Black-backed Gull that looked interesting, being obviously darker and smaller than the surrounding birds. It was sitting pretty tight but I decided to take a few record shots, assuming that it was an intermedius.

Initial views of the bird obscured in the grass

After a few minutes it began walking around and I was struck by its blackish mantle and structure - remarkably long-winged and attenuated at the rear end. I also realised that it was a subadult, with black markings at the end of the bill and only tiny white tips to the primaries. I began wondering if this could be a 3cy Baltic Gull candidate, although knew that I had to get a shot of the open wing to assess the primary moult. The bird looked unusually advanced (more like a 4cy) and I was struggling to age it with any certainty.

The flock was soon spooked and the whole lot took flight - luckily, I was still looking through the viewfinder and had the camera in position to take some photos, although with rather suboptimal settings for a flying bird (shutter speed far too slow and only the central focus point active)! Whilst the photos are not the sharpest, I was pleased to document the spread wing from both the top and underside. Examining them on the back of my camera, I could see that there was no active moult and two generations of primaries present - a clear indicator of 3cy fuscus!

Blurred photo but really shows the difference in size with this 2cy Lesser Black-backed Gull

I think the photo below shows the moult limit most clearly, with the outer two feathers (P9/10) appearing more brown and translucent against the background, as well the tips being slightly less rounded and lacking the small white tips present on P1-8. All secondaries are third-generation feathers. The contrast between the mantle and outer primaries is limited (in graellsii and most intermedius there is typically an obvious difference in colour), and there is a slight brownish cast to the greater and primary coverts which is a good feature for aging immature birds compared with full adults. Other than the dark eye, black bill tip and lack of P10 mirror the bird appears remarkably advanced - it has a fully white adult-type tail (3cy birds across all three Lesser Black-backed Gull subspecies usually show a mixture of white and black-tipped feathers), an unmarked white underwing without any marks on the underwing coverts, and deeply saturated yellow bare parts. Based on the size, thin bill lacking gonydeal angle and rounded head, I think this is an obvious female.

3cy fuscus is currently not acceptable as a vagrant by most rarities committees in Western Europe, including the BBRC. Both graellsii/intermedius can also moult primaries in winter and thus have two generations of primaries as a 3cy in spring. With fuscus this moult strategy seems to be the default, whilst in graellsii/intermedius it is uncommon but tolerably regular. The reasoning, then, is that since this moult strategy is not unique to fuscus, it is theoretically possible for an intermedius to show features which overlap completely with fuscus, including blackish mantle and small, attenuated structure. Having said this, I've yet to find any photographs of ringed 3cy intermedius which look exactly like this bird... if anyone has any please send them! Indeed, the examples of advanced intermedius used to illustrate these arguments do just look like advanced intermedius rather than birds that are easily confused with fuscus. This Norwegian bird (link) is the closest I can find. Typical 3cy graellsii/intermedius tend to combine grey scapulars with a worn, brown, unmoulted wing (sometimes with a row or two of coverts replaced) - they are instantly recognisable in the same way that 3cy fuscus is a striking bird.

I'd also argue that some 3cy fuscus must be identifiable if they have retained second-generation primaries with small P10 mirrors. Whilst this relates to only a small proportion of birds, as long as a candidate can be confidently aged as a 3cy this surely rules out graellsii/intermedius, which never (or almost never?) show mirrors on their second generation primaries. As far as I can tell, this hasn't been stated explicitly in any papers relating to fuscus identification, so the BBRC probably hasn't recognised it as a potential criterion for identifying 3cy fuscus.

Whether this latest Stanton St John individual is a textbook 3cy fuscus or an unusually advanced 3cy (or indeed retarded 4cy) intermedius - which also happens to share the full range of typically fuscus features - should be weighed up against the fact that confirmed 2cy fuscus are now known to be scarce but regular in Britain. I do think that the BBRC already applies a probabilistic approach to the assessment of certain rarities, where a combination of many "soft" features is sufficient to separate e.g. Zino's/Feas/Desertas Petrel, so long as these features are sufficiently documented through good photographs. I hope that this will soon be the case with Baltic Gull and I do plan on submitting this bird. I also think some clarity in the literature would help the BBRC with these complex assessments.

A bit of a deep dive now into Lesser Black-backed Gull moult, so an early point to bail from this blog post if one is so inclined!

One thing I found baffling after looking through lots of photos of 3cy fuscus was how many of them show large mirrors on P10 as well has having a moult limit in the outer primaries. Initially I thought that this was a sample of birds that happen to show mirrors in their second-generation primaries, now retained as worn outers. However, having a P10 mirror on second-generation primaries is a relatively uncommon occurrence - and some of these photos showed large mirrors (crossing over both feather webs) rather than the small and indistinct mirrors found on second-generation primaries.

The literature seems rather confused on this topic and I spent quite a while trudging through various papers attempting to explain why this pattern is observed. One school of thought seems to suggest that some birds which acquire P10 later on will show larger mirrors as the bird will be older and therefore produce a more adult-like feather. These may be individuals that arrest their first moult cycle in the spring of their 2cy and then replace the worn, juvenile P9/10 with second-generation feathers a few months after their peers. However, I'm struggling to find evidence that later moult leads to accelerated progression of feather pattern towards an adult-like pattern - indeed, I would have thought this would be correlated with earlier rather than later moult.

I found a more complete explanation from Chris Gibbins, who had obviously gone through the same thought process. His paper here (link) speculates that some of these birds have already moulted into third-generation primaries in their second winter, and those that show a moult limit have therefore replaced the inners with fourth-generation primaries. The most advanced fuscus may have already replaced half their primaries with third-generation feathers in the summer of their 2cy - so it is reasonable to imagine that the rest of these are replaced on arrival in their wintering grounds. Some Baltic Gulls would therefore remain a year ahead of other Lesser Black-backed Gulls in terms of their progression.

This makes some sense - it also seems possible that third-generation primaries are variable enough to show the full range from completely lacking a mirror to having a relatively large mirror. Indeed, the moult limit on the Stanton St John bird is very indistinct, with the retained P9/10 being barely browner than the inner primaries and not particularly worn/tatty. I find it hard to believe that these feathers are more than a year old, and have been used for three long migrations. Compare with the 3cy Lesser Black-backed Gull behind it - the second-generation feathers on that bird seem more worn than on the Baltic Gull, despite being grown a few months later. If you assume that the moult limit in the outer primaries in 3cy fuscus is between second- and third-generation primaries, the criteria for identifying 3cy fuscus suggested by Winters (2006) in his Dutch Birding paper seems to make more sense for intermedius! Perhaps this could be explained by the bird having replaced its P9/10 in the late summer of its 2cy (i.e. a slightly slower-moulting fuscus).

It is unfortunate that the third and fourth generation primaries (especially the inner ones) look very similar on Lesser Black-backed Gulls, which means that it is hard to reconstruct the moult progression based on feather pattern alone. I would imagine that 3cy fuscus shows a lot of variation in moult, with some birds having a mix of second- and third-generation primaries and particularly advanced birds having fourth-generation inner primaries. Indeed, this is the conclusion of this article on gull-research.org (link - a fantastic resource) - scroll down to see a list of observed moult strategies in 3cy fuscus returning to Finland. The moult pattern shown by my candidate bird is described as the "common strategy". I guess then, the problem is how to age an unringed bird accurately in the first place, given that bare-part colouration is more variable - and then how these differ from 3/4cy intermedius.

It's possible that I have misunderstood all this completely so if anyone has any comments that would be greatly appreciated. Clearly I need to visit some fuscus colonies this year and get some experience looking at birds of various ages within their core range - again, looking for any recommendations for good sites!