An interesting Chiffchaff at Spurn

I stayed at Spurn from 11th to 13th October with a regular group of friends, formerly from Leeds, namely; Roger Barnes, Vaughan Lister, Paul Doherty, Mick Cunningham, Richard Hart and Martin Quinlan whilst James Lowen also a friend originating from Leeds was with another group of birders from Norfolk. 
There were still several Yellow-browed Warblers around following the influx on Sunday 8th October but, other than an Olive-backed Pipit found on the 11th, few new birds turned up during my stay which was characterised by gale force warm, southerly or south-westerly winds.
On the 12th a tristis type Chiffchaff was seen and photographed at the Crown & Anchor late afternoon and I spent much of the following day looking for, and then watching it. This blog post deals with its identification.
A force 6 southerly wind blew throughout the day but one of the few areas that offered some shelter was the band of trees in the car park closest to the Crown & Anchor. The tristis type Chiffchaff was reported again here early on and when I arrived at about 9:00 a Yellow-browed Warbler was seen followed by brief views of a rather grey Chiffchaff.
Fortunately the Chiffchaff appeared to be on a circuit and every 30 minutes or so reappeared at the most westerly end of these bushes.
There were several birders present and it was interesting from the start how the appearance of the bird varied to different observers with some immediately dismissing it as nominate collybita. Of those who had seen the tristis Chiffchaff early on some were of the view that this was a different bird. As the Chiffchaff did a circuit and reappeared some considered that there was more than one bird involved including a typical nominate collybita and a paler bird!
The day started off heavily overcast but occasionally the sun shone through and this certainly altered the perception of the birds colouration as did the extent to which it was in shadow in the foliage.
To my eyes the Chiffchaff always looked greyish on the crown and mantle and especially so on the nape. Whilst the edges to the remiges and retrices were fringed olive green. The underparts were pale buff with a yellow tinge to the breast sides and undertail. The supercilium was prominent infront of the eye and also tinged yellow as was the upper eyelid. The legs were black as was the bill but with slightly paler sides at its base visible in the photographs but I thought it looked entirely black in the field.
Several observers commented that the overall impression of grey above and pale below with greenish fringes to the wings and tail was slightly reminiscent of the Bonelli's Warblers. 
The bird called repeatedly at times giving a slightly disyllabic hoo-eet which to my ears was fairly typical of nominate collybita. The noise of the wind in the trees put me off attempting to record the call although in hindsight any recording is better than none!
Photographs
I took photographs when ever the bird appeared during a couple of hours in the morning and a further hour in the late afternoon. Most of the time it was overcast but there was some sunshine when photo 4 was taken.

My camera, a Canon DSLR, is set on neutral so no sharpening or colour toning changes are made when the photo is captured. White balance is left on auto. On the computer I've made slight adjustment to the overall brightness of the image and sharpened them slightly but haven't altered clarity, vibrance or saturation. These images should be as close to how the bird appeared as Canon can make it.

Photo 1 

Photo 2 taken in shadow the bird looked darker above

Photo 3 the breast has some fine yellow streaks when seen close

Photo 4 taken with some sunshine the mantle looked slightly more olive and the fringes to wings and tail are brighter

Discussion
I posted Photo 1 on Twitter and got some helpful comments which directed me to a recent British Birds article (Vol 111 July 2018 pages 389-394) and other web resources which have addressed the identification of the races of Chiffchaff with particular reference to the use of DNA from trapped birds. The excellent and detailed summary by Alan Dean on behalf of the BB tristis panel is probably the best starting point for anyone with any interest in the racial identification of Chiffchaffs. Mick Cunningham also put me on to Vincent van der Spek's blog 'Turnstones' which has some interesting information on Chiffchaff ID from ringing studies in the Netherlands.
My initial thoughts were that the presence of yellow on the supercilium, breast sides and undertail plus the lack of chestnut/ brown on the ear coverts excluded tristis and that this bird was more likely therefore to be abietinus was a somewhat over simplified view given the latest published findings.
The appearance of abietinus is now thought to be much closer to collybita and there are few verified (by DNA) records in the UK. This is odd given that the range of abietinus is closer to the UK than tristis and one might therefore expect more records, unless their appearance is so close to collybita that they are overlooked. 
A 2012 paper in Dutch Birding (DB 34 (6) 386-392) provides results of mtDNA analysis of 41 birds trapped in the autumn of 2009-2011 which did not look like typical collybita (23 were identified as abietinus by the ringers handling the birds) or from very large birds, suggestive of abietinus. Of the 41, 11 were nominate collybita and 30 were tristis and no abietinus were identified in the group. 
At the Western edge of the range of tristis birds may show some yellow, particularly in the supercilium and these birds have been referred to as a separate race fulvescens. However, a 2017 publication by Shipilina (Patterns of genetic, phenotypic, and acoustic variation across a chiffchaff (Phylloscopus collybita abietinus/tristis) hybrid zone) concluded that genetic mixing of tristis and abietinus where the races are in contact is the source of plumage variation (chiefly occurrence of 'misplaced' yellow in the plumage) in tristis.
Conclusions
1. I know a lot more about racial variation in Chiffchaff and the identification of its subspecies than I did when I took the photos!
2. There was I think only one tristis type Chiffchaff in the area at the time and the appearance of the bird varied with the light and the extent to which it was shadowed by foliage. As demonstrated by the fact that birders stood close to each other had different pereceptions of the birds appearance.
3. The bird was probably an example of tristis/abientinus interbreeding often referred to as 'fulvescens'. These are birds from the western edge of the tristis range and are generally grouped with tristis and termed as Siberian type Chiffchaff and/or western tristis.
4. The call, to my ears at least, was typical for nominate collybita. Not sure how this fits in and I perhaps need to look in to call variation in tristis with the 'misplaced' yellow. 
5. A better starting point in the search for abientinus would be slightly larger nominate collybita with perhaps slightly greyer upperparts and less yellow underparts rather than odd tristis However, it appears that many abietinus may be inseparable from collybita in the field.   

Shetland Road Trip 25th Sept - 3rd Oct

Despite having spent more than 4 decades birdwatching in the UK I have never been to the Shetland Isles. So when Roger Barnes, a birding friend from Leeds, suggested a trip in late September I jumped at the chance. Roger already had a reservation on Fair Isle for 1st to 5th October where he was due to meet some friends so the timing of the visit was set around these dates.
There are a variety of ways to travel to Shetland and in the end we decided to drive in the camper and catch the ferry from Aberdeen to Lerwick. This gave us flexibility on the journey up and for our time on Shetland. We set off on 25th September with our first planned stop at Barns Ness, just over the Scottish border, where a 1st winter Woodchat Shrike had been showing well for several days.

Roger and I arriving at the aptly named Barns Ness

We arrived at Barns Ness in strong winds and overcast skies but there were a couple of other bird watchers in view and it turned out that they were watching the shrike and so were we within a few minutes of our arrival.

Woodchat Shrike 1st winter

A first winter Rose-coloured Starling had also been reported a few days earlier and in speaking to the locals we soon established that it was still present, feeding on the beach with Common Starlings. In the strong winds Starlings were flying in all directions but we persisted and eventually located the bird with about 30 Common Starling on the beach. Unfortunately the birds were flushed by another birder so we only managed rather distant views. 

Rose-coloured Starling with Common Starlings

The weather was forecast to improve later in the afternoon so we were keen to get to Musselburgh, our next stop.

Roger and I spent a week in Iceland in 2016 where we failed to find a regular summering White-winged Scoter so the opportunity to see a male that had been found in Spring this year was too good to miss.

Velvet Scoter - males

From the sea wall there were several groups of Velvet Scoter plus ones and two's spread over a kilometre or so. It looked like it might be a long task to search through them all but luck was with us again when we came across some local birders who had located the White-winged Scoter.

Once found, the pink rather than yellow, bill along with the swollen bill shape at the nostrils and large white tick behind the eye made it relatively easy to pick up, at least in good light.

White-winged and Velvet Scoter

White-winged Scoter

An adult Red-throated Diver moulting from summer plumage was feeding close to the seawall and provided a good photo opportunity.

Red-throated Diver - adult moulting from summer plumage

A Pectoral Sandpiper was also present on the nearby lagoons and we managed to locate this bird before dark and again the following morning where there were also two juvenile Curlew Sandpipers but all were distant telescope views.
From Musselburgh it was none stop to Aberdeen for our 7pm ferry to Lerwick. The wind was still blowing so the prospect of 12 hours on a rough sea was a little daunting but in the end the crossing was OK and we arrived on time in Lerwick.

Fulmar

The wind was still blowing westerly and there were few birds reported on Shetland so we did an initial tour of the southern part of Mainland calling at Sumburgh where we watched the Fulmars still occupying their nesting cliffs, Scatness where a Sabine's Gull was reported, Quendale and finally Levenwick.

Quendale Mill - scene of many rarities in the past

Here we had good views of a striking male Northern Wheatear which must have been of the Greenland race leucorhoa with rufous chest and tail with broad black band.

Northern Wheatear of the Greenland race leucorhoa

We stayed overnight at the Sumburgh Boating Club for £10 with electric, which would have been a great location at the mouth of the Pool of Virkie, had it not been for the gale force westerly which rocked the van all night.
The following morning we returned to Quendale which held a single Blackcap, then on to Levenwick where we added Chiffchaff and a Whinchat. News of a Common Rosefinch at nearby North Voxter took us slightly further north and after some great views of Twite the Common Rosefinch finally made an appearance.

Twite

Common Rosefinch - first winter North Voxter

We moved further down the coast to Sandwick for another Common Rosefinch and the coastal village of Leebitten became our base for the rest of our stay.

Leebitten in the foreground with the houses of Sandwick on the horizon

Common Rosefinch - first winter Leebitten

We were watching the weather closely but there appeared to be no sign of a let up in the west or north westerly winds. Our strategy was to find something scarce under our own steam. News of a White-crowned Sparrow on Foula joining the White-throated Sparrow found earlier in September was tempting but then came news of a River Warbler and Buff-bellied Pipit on Unst which already had American Golden Plover and Citrine Wagtail. In the end we decided to carry on covering the south Mainland area which, in hindsight, was probably a mistake and Unst would have been a better bet. Especially when a Pechora Pipit and Eastern Yellow Wagtail were found on 3rd October. We saw plenty of Wren of the darker, long-billed race zetlandica and had a good look at the Rock Doves which are probably as pure as any I'm likely to see in the UK.

Wren Troglodytes troglodytes zetlandicus (or borealis as classified by some)

Rock Dove

The wind continued to blow and we finally decided to give Fair Isle a miss, many of the planes from Lerwick were being cancelled and there was the prospect of being stuck for several days with no birds.
A pair of Snow Bunting at Grutness gave superb views as did a winter male Lapland Bunting nearby but we found nothing new. 

Snow Bunting

Lapland Bunting - ad male winter

A Marsh Warbler in Sumburgh quarry give brief views and we made a foray to Lunna at the north of Mainland where a Melodious Warbler had been found but the wind was so strong we struggled to stay upright and never located the bird which stayed for several more days.
On our final day we had decent views of Barred Warbler at Southpunds, made a final friutless search for a Blyth's Reed Warbler in Lerwick before having a look at the Black Guillemots in Lerwick harbour and heading for home.

Black Guillemot - adult winter

Overall we had a thoroughly enjoyable trip, and it was interesting to see so many famous places that have held major rarities in the past. It certainly felt like we could have encountered a rarity almost anywhere, but sadly we didn't!

Tarifa 6th - 12th September

We had no plans to return to Tarifa this year but checking flights at the end of August there were some good Ryanair deals to Malaga (return flights for the two of us at £213) so we decided to go at fairly short notice. I thought the car hire was too good to be true with Goldcar at £50 for the week, and it was, as we had to take their insurance at £147 when we picked up the car at Malaga Airport. We booked accommodation in Tarifa at the Hostal Tarifa close to the centre which was a great location for the town, beach and the Cazalla and Trafico watchpoints. The hotel was exceptionally clean, did a basic continental breakfast from 08:00 but no other meals which suited us.
First morning we headed up to Cazalla, a fly-by Golden Oriole was a good start and we soon started to see the first birds of prey with small groups of Honey Buzzard, Short-toed and Booted Eagles. Numbers of Griffon Vultures started to appear as the air warmed and we learned of a cow carcass below the watch point which had attracted large numbers of Griffon Vultures yesterday as well as at least 3 Ruppell's Vultures Griffons. I met fellow British birders Steve Duffield and Paul Eele and after Paul and his partner had moved on Steve and I were scrutinising all the Griffons .By mid-morning the Griffons were drifting closer, showing some interest in yesterdays carcass location although they never landed. Eventually we picked up an approaching dark bird which turned, showing the pale patagial line and pale tipped body feathers with underwing coverts and body as dark as the flight feathers, clearly Ruppell's Vulture. From the photos the serrated edge to the hindwing were clearly juvenile feathers with some fresh looking inner primaries suggesting it's probably a second calendar year.

Ruppell's Vulture - probably second calendar year

As we continued to check the vultures another dark bird passed overhead. Initially I thought that this was probably a Ruppell's also but on checking the photos it lacks the distinct pale patagial line and the body and underwing coverts don't have the pale edges of the classic Ruppell's. Could this be a hybrid Ruppell's x Griffon Vulture? I did find a photo of one in Israel in July/Aug 2014 but that would presumably be the east African race of Ruppell's, erlangeri, which is a much paler bird in any case.

Possible hybrid Griffon x Ruppell's Vulture

Still looking closely at the vultures, a wing tagged Griffon came by then another darkish Griffon so perhaps the bird above is just a dark Griffon?

Griffon Vulture wing-tagged

Griffon Vulture - a dark probably second calendar year

Mick Cunningham, a friend from the UK who had been out for a week already, arrived a little later but the Griffons were then distant dots over the hillside. Small numbers of raptors continued to pass including at least 3 juvenile Montagu's Harriers and a single Black Stork plus several parties of Bee-eater and Pallid Swift. Mick had mentioned a spot with several Black-eared Wheatear on the outskirts of town so I went looking for that them in the afternoon, stopping at the start of the Santuario de la Luz road on the way. I had nice views of a juvenile Woodchat Shrike here and less good views of a Melodious Warbler but couldn't find the wheatear spot.

Woodchat Shrike - juvenile moulting to 1st winter

The following morning I started at the fields bordering the beach at Los Lances.

Short-toed Lark - juvenile

Tawny Pipit - moulting adult

At least 8 Short-toed Larks were feeding in the fields plus 4 Tawny Pipits and several dozen 'flava' wagtails which were presumably Iberian Yellow Wagtails but none came close enough to confirm. There were a few waders; single Bar-tailed Godwit and small flocks of Sanderling, Ringed Plover and Dunlin with a scattering of Kentish Plover on the beach.
I finally found Mick's La Pena area which was at km 78.5 not km 76.5 as I had thought. I think the area is actually Valle del Santuario. Whatever its called it was good for wheatears with at least 5 Black-eared and two Northern Wheatears during several visits during the week. The group included 2 dark throated and a pale throated adult males, a 1st winter male pale throated and 1st winter female. So provided a great opportunity for a close look at this difficult to identify species and western race.

Black-eared Wheatear - adult male pale throated form

Black-eared Wheatear - adult male dark throated form

Black-eared Wheatear - 1st winter male pale throated form

Black-eared Wheatear - female, difficult to age (also two photos below of same bird)

The wind stayed in the west for the next 5 days until the 10th when it shifted 180º overnight to a force 5 easterly with low cloud over the hills. Until the wind shifted there had been a steady migration of raptors; Honey Buzzards, Black Kites and Short-toed and Booted Eagles numbering several hundred of each per day plus a handful of Montagu's Harriers and other migrants like Black and White Storks and Bee-eaters. On the 9th a distant imm Bonelli's Eagle was seen to stoop at a Black Stork and then follow a flock of White Storks but without further action.

Bonelli's Eagle, probably 2cy below a flock of White Stork

On the morning of the 10th the wind moved round to a force 5 easterly with low cloud over the mountains and raptors appeared to be circling along the coast with no clear destination. Several hundred Black Kite were blogging around the Trafico watchpoint with more visible to the east all remaining close to the coast. In strong winds I decided to have a look in the sheltered trees by the nearby Migres offices. I soon found Bonelli's Warbler and several Garden Warblers and Blackcap with single Common Redstart and an Iberian Chiffchaff that sang briefly.

Coastal path below Trafico with Morocco in the distance

The following morning in what was perhaps a gusting force 6 easterly the coast was fairly cloud free but there was heavy cloud immediately inland. There were perhaps 500 Black Kite attempting to fly east but many were landing on the hillside close to Trafico presumably waiting for the wind to subside.

Black Kites resting from the strong easterly wind

Many birds continued to move slowly east, some coming very close to the watchpoint.

Black Kite adult left foreground with juv inset to right

After a couple of hours at Trafico we drove inland to Facinas and then drove down the Santuario de la Luz road. Large groups of raptors were following the line of the road heading towards the coast. Several hundred Honey Buzzard were counted but there must have been several times this number across the valley, and I only watched for about 45 mins so it could have been thousands during the day. There were also Short-toed and Booted Eagles but fewer Black Kites here.

Honey Buzzard - male

Short-toed Eagle at eye level

The following morning was our last in Tarifa, the wind was still strongly in the east but there was a dense cloud cover with low cloud over the mountains. I counted at least 200 Short-toed Eagles in 2 hours ( I understand the count for the 12th at Cazalla was 2000 Short-toed!) along with 100 Booted Eagles, at least 500 Black Kite, several hundred Honey Buzzard, 20 close Black Stork and 50 Egyptian Vulture. It was an amazing sight to see clouds of raptors circling low over Tarifa, a spectacular end to a great week at Tarifa.

Black Stork juvenile

Some observations on adult Mediterranean Flycatchers on Corsica

Following DNA and morphological studies of Spotted Flycatchers on Corsica, Sardinia and the Balearic Islands published in 2015 (see footnotes for references) the International Ornithological Congress (IOC) split the species into Spotted Flycatcher and Mediterranean Flycatcher with the latter including the nominate Muscicapa tyrrhenica tyrrhenica and the Balearic Island subspecies M t balearica. In January 2018 the BOU adopted the IOC World List for taxonomic purposes and therefore the Mediterranean Flycatcher is a potential addition to the British list. 

This has not been universally accepted and some authorities still treat tyrrhenica and balearica as a race of striata, including the just published Handbook of Western Palearctic Birds by Shirihai & Svensson.

Whatever the ins and outs I'm interested in geographical variation and so a trip to Corsica in July was an opportunity to have a look at the flycatcher for myself. 
The Mediterranean Flycatcher is common on the island and I saw them in the mountain villages to at least 1000m and down to sea level. On the coast the breeding density was particularly high and I had 3 pairs in a 400m strip of pines close to where I was staying.

Generally Mediterranean Flycatcher appears a warmer brown without the grey tones of striata and the breast has less distinct dark streaks and appears more blotchy. In some lights the upper breast can appear almost unstreaked. The effect of the light was very significant, birds looking much browner and less streaked in the strong Mediterranean sun and greyer and more streaked in shadow.

Photo 1 Mediterranean Flycatcher - left in sun, right in shade

Both the above photos are of the same bird taken straight from the camera without any adjustment, other than a little sharpening. Post processing adjustment particularly to the highlights have a big impact on how distinct the streaking appears and on the plumage tones.

Photo 2 Mediterranean Flycatcher as above with post processing adjustments

So the lighting conditions are important when assessing colour and the extent of breast streaking, as is the photo post processing when looking at images.

Photo 3 Mediterranean Flycatcher (left) v Spotted Flycatcher (right)

Photo 3 shows the extent and strength of the breast streaking on the two species. Note how brown the Spotted looks in the sunlight compared to Mediterranean in the shade. The bill looks slightly thicker on Spotted, having a slightly more swollen appearance?
There may be slight differences in the streaking of the crown and nape but I couldn't see anything consistent.

Perhaps the most significant quoted difference between the two species is primary length with Spotted generally having the primary extension greater than the exposed tertials whilst in Mediterranean the primary extension is less than the exposed tertials. This is very difficult to assess in the field and is best done from photographs but they are very dependent on the angle and stance of the bird and also on the condition of the feathers.

Photos 4 & 5; Mediterranean Flycatcher estimation of primary extension (Note lower bird has very worn longest tertial)

Photo 6; Spotted Flycatcher estimation of primary extension (© Ken Smith)

The paper by Michele Vigano & Andrea Corso gives a range of wing measurements and demonstrates that Mediterranean Flycatcher has a shorter wing length, on avarage by 4.6mm,  and more rounded wing. Differences in the primary spacing on the closed wing could therefore be apparent, in the article the most significant difference found was between the longest primary p3 and p2 which unfortunately isn't visible on the closed wing.

Photo 7; Mediterranean (L) v Spotted Flycatcher (R) primary spacing

Apologies if I have the primary numbering incorrect. On the Spotted Flycatcher p3 is longest but this is variable and it doesn't look to me as if there is any obvious difference which would help in the field.

Photo 8; Mediterranean Flycatcher in a typical view, length of the primaries compared to the undertail coverts doesn't appear to help in separating the species presumably due to posture factors

Both Corso & Vigano have stated on BirdForum that an article on the identification of Mediterranean Flycatcher, or Tyrrhenian Flycatcher as they prefer, is in preparation for Dutch Birding. I no longer subscribe but don't think this has been published yet? Andrea Corso also stated that the 'call is clinching too' on BirdForum but didn't elaborate. The Mediterranean Flycatchers were generally vocal and the call was consistently a high pitched seeep usually ending with a tchak. In the UK I most commonly here the seeep alone but have also heard the seeep - tchak. The birds in Corsica were feeding young which may have influenced their calls. I haven't analysed the calls to see if there is any quantifiable difference in frequency. I made a recording which is available below.

In conclusion I think a Spring flycatcher with warm brown tones to the upper parts and subdued breast markings, comprised of brownish blotches rather than distinct dark streaks would be worthy of closer inspection and a primary projection of less than the exposed tertials would be a strong indication of Mediterranean Flycatcher. 
M t balearica is paler and has a slightly shorter wing length (BWP) than nominate tyrrhenica so the features described above should be slightly more obvious in that race of Mediterranean Flycatcher.
If there is a vocal difference that would be an additional factor and possibly a clincher to quote Andrea Corso. 
All the flycatchers are interesting and worth a close look in any case.

Michele Viganò & Andrea Corso; Morphological differences between two subspecies of Spotted Flycatcher Muscicapa striata (Pallas, 1764) (Passeriformes Muscicapidae). 

Biodiversity Journal, 2015, 6 (1): 271–284

Pons et al ; The role of western Mediterranean islands in the evolutionary diversification of the Spotted Flycatcher (Muscicapa striata), a long-distance migratory passerine species. 
Journal of Avian Biology 47(3) · November 2015