Juvenile Yellow-legged Gull

August 15, 2013, 12:49 pm

≫ Next: Leicestershire & Rutland Annual Bird Report

I visited Cotesbach landfill site late yesterday afternoon and many gulls were loafing about in the quarry. Searching through them, I had found nothing of particular interest until I got to the very last gull.

Juvenile Yellow-legged Gull

As soon as I saw this bird I knew that it was a juvenile Yellow-legged Gull. It was a big individual with a thick neck, large head and a solid all black bill. The large pale head and chunky bill rule out LBB Gull and the tertial pattern rules out Herring Gull. Herring Gulls should have pale notches on the tertial fringes. Other supporting features include the greater covert pattern (barred on the lower ones and plain on the outer ones) and the dark mask around the eyes. Importantly, at least one of the scapulars is a 2nd generation type. It is not normal for juvenile Herring and LBB Gulls to start to moult their scapulars so early in the year. Also note the black outer tail band and the white upper tail coverts.

Having spent so much time studying the gulls at Shawell it is really satisfying to be able to ID birds like this. One of the reasons for putting in so much effort was to be able to ID the immature birds. Hopefully I'll find a juv. Caspian Gull soon.

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Leicestershire & Rutland Annual Bird Report

August 19, 2013, 12:22 pm

≫ Next: Tricky Juveniles

≪ Previous: Juvenile Yellow-legged Gull

I picked up my copy of the 2011 Annual Report on Saturday at the Rutland Water Birdfair. I didn't, however, spend a great deal of time reading it, as one of the joys of being Editor is not wanting to read it again after all the proof-reading etc.

After six years, as Editor I've handed over the helm to Mark Skevington who has kindly taken on the role. I wish him luck and I now look forward to sitting in my armchair reading the next report for enjoyment.

During my time as editor I've had a great deal of help from the editorial committee, and so I would like to thank them all once again for their efforts. I must also thank John Wright for helping with illustrations each year. They really lifted the publication in my opinion.

Anyone without a copy that wishes to read it should either join LROS and get a free one or purchase the report from Sue Graham - DETAILS HERE

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Tricky Juveniles

August 24, 2013, 12:49 am

≫ Next: 3rd Year Caspian Gull

≪ Previous: Leicestershire & Rutland Annual Bird Report

My previous posting about a juvenile Yellow-legged Gull at Cotesbach landfill site seems to have been popular. As such I thought I'd waffle on a bit more about large white headed gulls in their juvenile plumage. I failed to find any juv. YLG's on Wednesday night, but I did spend plenty of time looking closely at the juveniles of the commoner species that were there.

Juvenile Lesser Black-backed and Juvenile Herring Gull

The middle bird in the photo above is a juv Herring Gull and the one in front of it is a juv. Lesser Black-backed Gull. Before identifying a juv. YLG or Caspian Gull a good working knowledge of the other two species is essential. Of course it is not always easy and there will be many opportunities to get it wrong. This particular Herring Gull, from my experience, has notches on the tertials that are larger than most. The tertials are the horizontal feathers to the left of the long black wing tip feathers (sorry if you know this already). The notches are the cream coloured triangular shaped markings on the brown feathers. Not all tertial notches on juv. Herring Gulls are as obvious, but notches of some sort can almost always be seen unless the feathers are really badly worn. The tertials of juv. LBB Gulls are dark brown with pale buff fringes To me, juv. Herring Gulls always appear to be slightly frosty in comparison to the more dusky juv. LBB Gulls and the large head size of HG is usually distinctive. HG bills are usually obviously more bulky than LBBG's, but not always as there are a few large juv. LBBG's to contend with.

Juvenile LBB Gull

On Wednesday night I estimated that there were at least 3000 Lesser Black-backed Gulls loafing around at the landfill site. There were still about 20 YLG's, 30 Herring Gulls and a lone GBBG.

Third-winter Yellow-legged Gull

Amongst the gulls on the A5 Lagoons were at least nine YLG's and the one above was a real monster. He took great pleasure in bossing the other gulls about.

A Couple of YLG's from Wednesday 21/08/13 (left and back)

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3rd Year Caspian Gull

August 24, 2013, 1:06 pm

≫ Next: More Juvenile Yellow-legged Gulls and Stuff

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The gulls were gathered at Cotesbach landfill site in their thousands again today. The weather wasn't quite as bad as the forecast suggested, so the visibility was reasonable. The working face of the tip was a bit too high for me to see the feeding gulls well, but a YLG moulting into 1st-winter plumage showed well on the near edge of the mound.

I moved to view the gulls resting and bathing in the quarry. Amongst the gulls was a splendid juvenile Herring Gull, which was attired with a big yellow ring with the code F+C. This gull was ringed in Gloucester.

A 3rd year Caspian Gull flew on to the pool in the quarry, but only took a drink and then flew off. Luckily I relocated it in the afternoon at Shawell A5 Lagoons. It showed very well for much of the afternoon. It was moulting its primary feathers although some old ones were still present but quite faded. A new primary is visible in the photographs though it is not fully grown. The bird shows the typical profile, which seems to be most obvious at this age, a smallish head and a long body with a low profile. The small dark eyes are set forward and the bill is typically washed out and slender. Also note the 'pencil markings' on the side of the neck.

The head is perhaps not the smallest I've seen, but it is within the range, as far as I can determine by studying many photographs. The head size varies just like in other similar gull species. This birds head still looks small in relation to the long body.

3rd-winter Caspian Gull

3rd-winter Caspian Gull (note the body length compared to the LBB Gull)

3rd-winter Caspian Gull with Intermedius LBB Gull

This bird is a calendar year younger than the one I saw in July - see HERE

Comments are welcomed - even if you disagree with my ID.

Of interest, all of the above photos were taken using a Canon DSLR attached to my scope.

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More Juvenile Yellow-legged Gulls and Stuff

August 29, 2013, 4:01 am

≫ Next: Mediterranean Gull

≪ Previous: 3rd Year Caspian Gull

Hasn't the weather been good this summer? After moaning about the constant rain, wind and hail storms last year it has been really good to keep waking up to another bright day. There have been plenty of butterflies around, which bodes well for future years. The buddleia in my garden is alive with Peacocks and Tortoiseshells plus at least one Painted Lady. In all I've seen eight species in the garden over the last week.

Painted Lady

A pair of Ravens reappeared where I work yesterday and announced themselves very noisily. They were present all day and will probably be around all winter now.

I am starting to make a habit of visiting Shawell A5 lagoons after work on Wednesday evenings and last night was no exception. The Black-tailed Godwit that was first seen on August 22nd was still present. Three Black-tailed Godwits at this small site, so far this autumn, is pretty impressive as far as I'm concerned. I'm still waiting for either a Little Stint or Curlew Sandpiper, but there's still time.

The gulls were around, but someone was shooting close by, which was making them nervous. I did manage to find two more juvenile Yellow-legged Gulls amongst them.

One was a very young bird bird and the other was almost in first-winter plumage.

Juvenile Yellow-legged Gull with Juvenile Lesser Black-backed Gull

Juvenile Yellow-legged Gull

The second juvenile appeared soon as the first one, but this one was clearly older. The basic features were similar to the first one, but this one had replaced almost all of its mantle and scapular feathers plus its coverts and tertials were very worn. In the photos above it looks quite scruffy around the head and neck, but this was because it had been washing quite vigorously.

Juvenile Yellow-legged Gull Moulting into First-winter Plumage

Both birds had pale heads and necks with a dark mask around their eyes. I had the opportunity to compare them to juvenile Herring and Lesser Black-backed Gulls at close range and the differences were very obvious. In flight both of these birds showed a thick black tail band contrasting with a white rump and upper tail. Herring Gulls show less contrast between the tail band and the upper tail.

The bird in the photo below is the same as the one in the picture above, but this was taken later on when it had dried out.

Juvenile Yellow-legged Gull

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Mediterranean Gull

August 31, 2013, 2:04 pm

≫ Next: Keep an Open Mind

≪ Previous: More Juvenile Yellow-legged Gulls and Stuff

Below is a short video of a juvenile Mediterranean Gull that I found at Shawell A5 Lagoons, Leicestershire on August 31st:

Black-headed Gull numbers had increased since my last visit and amongst them was a smart juvenile Mediterranean Gull. It is just over twelve months since I last found a Med Gull at the site and that was also a juvenile.

Juvenile Mediterranean Gull

Yesterday was another good day for Yellow-legged Gulls at Shawell with at least 11 different individuals present on the A5 Lagoons. Amongst them were two juveniles: one that was also there last Wednesday and a new bird. Three 2nd-winter birds were also seen, one of which is pictured below. No Caspian Gulls were seen, but their numbers increase in winter whereas Yellow-legged Gull numbers fall during the winter months.

2nd-winter Yellow-legged Gull

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Keep an Open Mind

September 1, 2013, 11:07 am

≫ Next: First-winter Yellow-legged Gull

≪ Previous: Mediterranean Gull

Adey Baker and I did our regular Sunday morning walk at Croft Hill & Quarry today. We had Redstarts and the like in our sights, but we have learnt over the years that you need to keep an open mind. Often its a species that we hadn't even considered that makes the day.

Apart from a few Blackcaps things had been very quiet, but a few seconds of high energy birding saved the day. On our way back from the embankment to the hill you follow a footpath that brings you close to the quarry edge. I looked out over the quarry and noticed two small groups of what appeared to be waders flying towards us and they were not very high in the sky. They were quickly forming up into one flock of seven birds. They had long straight bills, so I instantly shouted 'godwits'. They flew behind a tree and then back into view. We could now see them from behind, but instead of seeing black tails and distinctive white wing bars, we saw greyish brown wings with faint brownish tails and white wedges on the uppertail coverts and a little way up the back. I think both of us were a little stunned by the realisation that they were Bar-tailed rather than Black-tailed Godwits. The legs were not visible to us whereas Black-tailed Godwits have legs that project well past their tails in flight. We both agreed that they were Bar-tailed Godwits and happily ruled out other similar wader species. The views had been good considering, luckily they were not high in the sky or distant.

The timing of this sighting is spot on, as this is the peak time for this species in Leicestershire and Rutland according to statistics in Birds of Leicestershire and Rutland.

This is only the third record for the south-west Leicestershire area after four at Frolesworth Manor lake on May 14th 2001 and a single at Brascote Pits from May 6th to 12th 2012.

Bar-tailed Godwit, Norfolk

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First-winter Yellow-legged Gull

September 14, 2013, 10:00 am

≫ Next: More Gulls

≪ Previous: Keep an Open Mind

It doesn't seem five minutes since I spotted the first juvenile Yellow-legged Gull for the year at Shawell. It was actually July 27th and the bird was in fresh juvenile plumage. Things have progressed rapidly, so much so that I spotted a YLG in first-winter plumage on Thursday afternoon. It is well known that Yellow-legged and Caspian Gulls generally hatch earlier in the year than Herring and Lesser Black-backed Gulls. As a result their progress towards first-winter plumage is more advanced than the northern species, which are still juvenile like and much fresher looking.

First-winter Yellow-legged Gull

I have seen at least four first-calendar year YLGs over the last couple of months at Shawell. The latest one, in the photos above and below, is the most advanced. The mantle and scapular feathers have been replaced with second generation feathers and the coverts and tertials are quite worn. Note the distinctive anchor markings on the mantle and scapular feathers.

First-winter Yellow-legged Gull

Thursday was a difficult day, as many of the gulls were sitting out of view at the landfill site and only a few were visiting the A5 Lagoons. I did manage to read colour rings on three Norwegian ringed LBBG and also a Belgian ringed LBBG. Late in the afternoon a decent 'wave' of gulls came over from the tip and settled on the main lagoon. Amongst them was the first-winter Yellow-legged Gull plus four adults and a third-winter. The adult Yellow-legged Gulls can be distinguished easily at present from most Herring Gulls of the same age as they are actively moulting their primary (wing tip) feathers.

Third-winter Yellow-legged Gull

Third-winter Yellow-legged Gull

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More Gulls

September 25, 2013, 11:05 am

≫ Next: Second-winter Caspian Gull

≪ Previous: First-winter Yellow-legged Gull

I spent sometime at Shawell again last Saturday for a change and once more first-winter Yellow-legged Gulls were the highlight.

The first bird was most likely a female as it was a petite individual. I was happy that all the key features were visible including quite pale underwings. The tail had a black band which tapered at the outside edge and the rump and uppertail coverts were white with a few black spots. The nearby first-winter LBBGs had brownish underwings and the rumps and uppertail coverts were dull brown with extensive spotting.

First-winter Yellow-legged Gull

In contrast to the first bird, the second one was a real monster. The plumage of the YLG in the photo below is, I believe, more advanced than that of the one in the first photograph.

First-winter Yellow-legged Gull

Since my last posting, some fist year Herring Gulls are starting to replace their mantle and scapular feathers, so this feature has to be used with caution now when looking for first year YLGs. Below is a video of some of the first year YLGs and a short section of the third-winter Caspian. Look out for the Suffolk ringed Lesser Black-backed Gull and the escaped White-cheeked Pintail.

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Second-winter Caspian Gull

September 26, 2013, 2:02 pm

≫ Next: Portugal

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Half an hour at Shawell A5 Lagoons today rewarded me with great views of a second-winter Caspian Gull.

As long as the local Buzzards give the gulls long enough to settle they leave the safety of the water and move onto the bank that separates the two lagoons. Just before I was about to leave I spotted this smart bird right on the top of the bank. I was travelling light so I only had my small compact camera and scope. Sadly I get quite a bit of vignetting with this camera and scope combination, but I've managed to crop the image to remove the problem.

Second-winter Caspian Gull

I was pleased to get the chance to study this bird, as it is the least mature second-winter I have seen. All the usual features are on show: upright stance, long sickly flesh coloured legs, white head with a beady dark eye, slender parallel edged bill and pencil mark streaking on its nape.

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Portugal

October 8, 2013, 1:58 pm

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I've just returned from an excellent trip to Portugal, based in the Algarve.

The birding was great with many highlights including somewhere in the region of 100 Booted Eagles and other raptors circling overhead.

I couldn't leave the gulls alone and ended up reading 60 different colour ring readings.

I am overwhelmed with paperwork as a result, but I will write a full trip report shortly.

The gull below was ringed by Peter Stewart, whose gulls regularly turn up at Shawell, so I was pleased to see it. The pose is great don't you think?

Lesser Black-backed Gull, Portimao, Portugal

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Portugal Trip Report

October 12, 2013, 12:59 pm

≫ Next: Yellow-legged Gulls in Southern Portugal

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I jumped at my good ladies suggestion that we should try Portugal for a late summer holiday. A few Jedi mind tricks helped her choose the destination, which as look had it was close to some renowned gulling sites. On September 27th we flew from East Midlands airport to Faro. From Faro we were transferred to our hotel at Praia da Rocha, near to Portimao. Azure-winged Magpies teased as they flew overhead in groups of up to 30 at times. White Storks and Cattle Egrets were seen seen feeding in roadside fields.

It was dark shortly after we arrived, so we found a suitable watering hole and then crashed out for the night. The following morning dawned a little overcast, but I headed in search of gulls and the location where we would be picking our hire car up from. I soon found a group of gulls on the beach and amongst them was two colour ringed Lesser Black-backs. I'll bore you in another posting about all the colour ringed birds seen on the trip.

Gulls on the Beach at Praia da Rocha

At 10 o'clock we collected our nice little Seat Ibizia and then a trip to the nearby small town called Alvor was the order of the day. Here we enjoyed a walk on the beach and the boardwalks that allow good views over the estuary. Four Med Gulls were seen: an adult and three second-winters. The estuary held good numbers of waders. It was similar to a day out to Titchwell to be honest, although a couple of Caspian Terns brightened up the day. Crested Larks flitted about as did migrant Wheatears. I turned to Dawn and said I'd be surprised if we didn't see a shrike on those distant bushes and right on cue one appeared - an Iberian Grey Shrike. She initially accused me of stringing, but accepted I was right after setting my scope up and making her look through it. This was the only shrike we saw along the coast.

Sanderling

An early start was required on Sunday for a trip to Castro Verde where we hopped to find 'steppe' species. The drive was about 60 miles inland from our base. We set off in the dark and it was raining, so driving was not that pleasurable, but at least the roads were quiet. The weather improved as we neared our destination. Corn Buntings and Iberian Grey Shrikes were everywhere, as were migrant Wheatears. Two Crag Martins hawked over a small stream and Pied Flycatchers flicked out from roadside trees. Our target species was Little and Great Bustards. We followed the map I found on the internet - HERE . Quite quickly we located a Little Bustard on the hillside and after watching that we spotted the distinct bulk of a Great Bustard on the horizon. In all we saw 23 Great Bustards, one Little Bustard and six Stone Curlews. The GB's were a bit distant for photography, but I did manage to get a bit of video footage of them.

WATCH A GROUP OF GREAT BUSTARDS - CLICK ON THE YOUTUBE LOGO FOR BEST RESULTS

Great Bustards

We explored further afield after filling our boots with the bustards and found an interesting river valley. The river must have been a raging torrent in the past as the dried bedrock had some really deep gouges in it. Out in the middle of the river was an ancient water mill, which was pretty impressive and a Green Sandpiper fed close by.

Ancient Water Mill

Searching for colour ringed gulls was the order of the day for Monday. The beach at Praia da Rocha and the fishing harbour at Portimao were productive, but a trip to the landfill site at Porto de Lagos beckoned - I know how to treat a girl!

Portimao Fish Harbour

Portimao fish harbour

Porto de Lagos Landfill

This place was amazing 1000's of Gulls and 100's of White Storks.

White Storks

Off for a Wash

Tuesday morning was spent at the fish harbour where I found the Azorean Gull and in the afternoon we wandered the old cobbled streets of Alvor.

Wednesday and Thursday were spent at the 'end of the world'. We enjoyed a Pelagic boat ride (not quite a cruise) out of Sagres - with Marilimitado

Dawn was enthralled by the Common Dolphins, but didn't appear to enjoy the chumming bit. It was quite rough and photography was quite a challenge.

The Second Boat

1st year Northern Gannet

Cory's Shearwater

Cory's Shearwater

Cory's Shearwater

As well as the birds in the photographs we had a Great Shearwater at point blank range (too rough to photograph well) and five Stormies, plus one each of Sooty and Balearic Shearwaters.

A visit to a nearby raptor watch point proved to be a good decision. At one time there must have been at least 100 Booted Eagles sawing above us along with a smaller number of Short-toed Eagles and a couple of juvenile Bonelli's Eagles. Honey Buzzards and a Goshawk were a great supporting act. Even better was an Osprey carrying a fish whilst being chased by a Black Kite

Raptor Watchpoint, Cape St Vincent

Juv. Booted Eagle

The area around Cape St Vincent is supposedly good for Thekla Lark. I spent quite a while studying the larks in the area and I'm pretty sure I identified and photographed at least a few Thekla Larks (correct me if I'm wrong).

Thekla Lark

Cape St Vincent was a good location for a sea watch and I added Great Skua to the seabird tally there. A Blue Rock Thrush and about half a dozen Black Redstarts frequented the cliffs and a couple of Pallid Swifts scythed the air above the lighthouse.

Cape St Vincent (believed to be the end of the world in ancient times)

Our time during the rest of the trip was shared between the fish harbour at Portimao, Monchique and Alvor. On the last day we walked from Praia da Rocha to Alvor along the coast. In parts the cliffs provided us with great entertainment as we scrambled up and down the rocky paths along the edge. Many migrants were seen including good numbers of Pied Flycatchers, Northern Wheatears and three Sub-alpine Warblers.

Northern Wheatear

The Algarve

In all we saw just over 100 bird species and had a great time.

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Yellow-legged Gulls in Southern Portugal

October 13, 2013, 11:56 am

≫ Next: Gallery of CR Gulls From Portugal

≪ Previous: Portugal Trip Report

As I've already mentioned, while I was in Portugal I wanted to take a good look at the Yellow-legged Gulls. These gulls should look similar to the ones we see in Leicestershire, but I was expecting to see some un-familiar ones from further north and west.

Most of them did look the same as the ones that turn up at various sites here in Leicestershire, but some had similar streaking on the head and neck to Herring Gulls at this time of year and maybe a more Herring Gull look about them.

Below is a selection of Yellow-legged Gulls taken in southern Portugal during late September and early October 2013. The first four are of adult birds that to me are not typical of the birds we see in the UK:

Ringed in South-west Spain

Next is a selection of typical adult Yellow-legged Gull Larus Michahellis:

As you can see none of the adult Yellow-legged Gulls above have anywhere near as much streaking on their heads as the Azorean Gull I photographed at the same locality.

Below is a selection of immature Yellow-legged Gulls:

First-winter Yellow-legged Gull

Second-winter Yellow-legged Gull

Retarded Third-winter Yellow-legged Gull

A few flight shots of a first-winter to finish with:

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Gallery of CR Gulls From Portugal

October 16, 2013, 11:09 am

≫ Next: Second-winter Caspian Gulls

≪ Previous: Yellow-legged Gulls in Southern Portugal

As I've already mentioned, during my trip to Portugal I read the plastic colour rings on 60 gulls.

Below is a selection of photos of some of these birds starting with my favourite image:

Lesser Black-backed Gull, J6UX, Norwegian Ringed, Regular Records from Spain and Portugal in Winter

Lesser Black-backed Gull, JJ9T, Norwegian Ringed, Recorded in Western Sahara, February 2012

Lesser Black-backed Gull, T:55M, Ringed in Aberdeen this Summer

1st Year Lesser Black-backed Gull, LLLJ, ringed in Suffolk

1st Year Lesser Black-backed Gull, Z.E, Ringed in Holland this Summer

Lesser Black-backed Gull, K.J, Ringed in Holland

Lesser Black-backed Gull, BO, Ringed in Holland

Lesser Black-backed Gull, 2.V3, Ringed on Sark, Channel Islands

Lesser Black-backed Gull, 4AW3, Ringed on Guernsey

Lesser Black-backed Gull, 3AC5, Ringed on Guernsey

Lesser Black-backed Gull, 6AJ6, Ringed on Guernsey

Ringed as a Lesser Black-backed Gull, M+C, but may be either a Herring Gull or a hybrid. Ringed in Bristol

CTY ringed in Gloucestershire

The last four were all rescued by the RIAS - Centro de Recuperação e Investigação de Animais Selvagens Ria Formosa. They were rehabilitated and released and are surviving well as you can see.

Juvenile Yellow-legged Gull F305

Second-winter Yellow-legged Gull F181

Fourth Year Yellow-legged Gull F052

Adult Lesser Black-backed Gull F196

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Second-winter Caspian Gulls

October 23, 2013, 12:38 pm

≫ Next: Azorean Gull in Portugal

≪ Previous: Gallery of CR Gulls From Portugal

Three different second-winter Caspian Gulls have graced Shawell A5 Lagoons over the past couple of weeks. Each bird had a different bill pattern and slightly different plumage. Photography was difficult due to the light and the distance involved.

The video below is great for seeing them just as I did. The poor light made it difficult to re-produce the grey on the mantle and scapulars as I saw it through my scope, but the first one on the bank shows how pale silvery grey they are. The first one is preening its breast in front of an out of focus piece of vegetation.

The last bird shows more contrast in the plumage than the other two and its dark bill adds to this effect. Check out the white underwings as it takes off. Other large gulls species will have more brown on the underwings at this age.

The first two are typical of 2nd CY Caspian Gulls at this time of year, but the third one appeared more advanced except for the all dark bill.

Head size appears to be variable amongst Caspian Gulls with some birds having noticeably small heads whereas some not so. Studying photographs, it may be that the head size decreases the further east they come from. Chris Gibbin's photographs of Caspian Gulls from the Ukraine seem show them having larger heads than those from Azerbaijan - see the list of blogs that I follow for a link to Chris's blog. I have seen some really small headed Casps with the one in the video HERE having a small head. It is impossible to know where most of our birds are coming from, but there have been some colour-ringed Polish birds in the county. Unfortunately there are supposed to be quite a lot of hybrids in Poland!

As always feel free to offer any comments or disagreements:

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Azorean Gull in Portugal

October 24, 2013, 11:30 am

≫ Next: A Couple of Interesting Immature Yellow-legged Gulls

≪ Previous: Second-winter Caspian Gulls

Last year I found a Yellow-legged Gull at Shawell A5 Lagoons, Leicestershire, which showed extensive head streaking and a primary pattern that resembled that of an Azorean Gull Larus michahellis atlantis, also known as Atlantic Gull. In the end I concluded that this gull was not an L. m. atlantis, but more likely a Yellow-legged Gull Larus michahellis from a western population due to its upper parts being too pale.

I was, however, intrigued by the gull at Shawell and other sightings of probable L. m. atlantis seen in the UK, so I decided to visit the Algarve in Portugal to study Yellow-legged Gulls Larus michahellis present there in autumn. I based myself at Praia da Rocha, close to the fishing harbour at Portimao. This site is excellent, as it is easy to study gulls at close quarters.

During my second visit to the fishing harbour, on October 1st, I spotted a very distinctive gull, which I immediately felt was a good candidate for being an Azorean Gull L. m. atlantis

Azorean Gull L. m. atlantis

Its mantle colour was mid-way between the Yellow-legged Larus michahellis and Lesser Black-backed Gulls Larus Fuscus that were close by for comparison. The grey was nearest to that of the LBBG sub-species graellsii, but unique in tone to any of the other gulls present. The head was densely streaked on the crown and ear coverts, but became less dense below the nape. The streaks were much darker than L. michahellis even though some of them were heavily streaked on the head.

It had the solid robust and short legged jizz of an Azorean Gull L. m. atlantis. These features are all obvious in the photographs. Its eyes are large and pale, which is also a good feature. The bill appears different to Yellow-legged Gull L. michahellis being thicker slightly shorter and more 'chisel' tipped due to the steep gonys angle.

The primary pattern matches the most often quoted for L.m atlantis. A single mirror on P10 and no mirror on P9. P5 has a very thick black band and P4 shows a dark mark on the outer web. The dark mark on P4 is larger than would be expected for L. michahellis. The extent of black on P8 and 9 is also greater than typical for Yellow-legged Gulls. It is true, however, that there has been no complete study of the primary pattern of Yellow-legged Gulls from the western population to see if there is a marked difference between L. michahellis and L.m atlantis. There are some older studies which point to L.michahellis from the western end of its range having a similar primary patterns to L.m atlantis. However, these birds don't show the full set of characters associated with L.m atlantis. The underside of the secondaries showed a light grey wash. I only noticed this when the bird stretched its wings while on the ground, but it is just visible in the photo below showing the underwing.

Primary Pattern on the Upperwing

Mirror on P10

Preening the Underwing

Underwing

Azorean Gull L. m. atlantis

There appears to be some controversy over whether Azorean Gulls actual leave the Azores and whether birds from Maderia and the Canary isles resemble the gulls from the Azores. As far as I can see there is nothing to suggest it is a hybrid and everything to suggest it is an Azorean Gull. The name Atlantic Gull is perhaps a more accurate name, as it may be difficult to prove which island this bird actually came from.

The extent of the streaking on the back of the head is interesting. In some photographs it appears to finish sharply at the back of the ear covets and across the top of the nape, but in others the streaking, although finer, can be seen to extend down to the base of the neck. The extent of the dark head streaking is obviously variable click HERE for a group photo of Azorean Gulls showing different head patterns. The main thing is that the gull at Portimao shows head streaking outside the range of Yellow-legged Gull and the streaking is different to that shown by Lesser Black-backed Gull - the streaks are finer but darker and not blotchy.

I have already asked a couple of people whose views on gull ID I respect and the replies were encouraging:

"I think a bird like that seen anywhere would be called an atlantis, based on grey tone, head streaking and wing pattern".

"Wow, what a bird. To me everything about this bird says Azorean Gull – plumage and structure".

As always, I welcome any comments.

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A Couple of Interesting Immature Yellow-legged Gulls

October 25, 2013, 1:05 pm

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During my trip to Portugal in late September and early October I photographed a couple of immature colour-ringed Yellow-legged Gulls, which I identified correctly. However, I had a few lingering doubts. The first one was in juvenile plumage, which was unusual as all the other first year Yellow-legged Gulls had made good progress towards first-winter plumage. The fact that it had been taken into care might well be the reason for it still being in juvenile plumage as stressed birds often stall their moult.

Juvenile Yellow-legged Gull

The other YLG's of a similar age had replaced most of their mantle and scapular feathers along with some of their coverts like the one in the photograph below:

First-winter Yellow-legged Gull

The other one (pictured below) was a second-winter bird and although its general character fits YLG, its plumage is not typical. It is much darker than I'd expect and it is very similar to the second-year Lesser Black-backed Gull behind it. The bill appears good for YLG as does the dark mask behind the eye and the large head size. It is resident in Portugal which helps point towards it being a YLG, as LBBG should move north in summer. It is healthy and able to fly as it moves along the coast between Portimao and Quarteira. Once again the plumage could be retarded due to the time it spent being rehabilitated. I might struggle with one like this if it turned up at Shawell.

Second-Year Yellow-legged Gull

Below is a more typical second-year YLG:

Second-year Yellow-legged Gull

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Azorean Gull Again

November 1, 2013, 3:51 pm

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I'm still working through my gull photos from Portugal and researching the gull I consider to be an Azorean Gull. The experienced gull watchers that I've asked have either energetically or cautiously agreed with my ID. However, a couple have suggested that it may have come from either Madeira or the Canaries rather than the Azores, as the Yellow-legged Gull populations from these islands can look the same as those from the Azores. I think this is a just in case remark.

Photographic evidence appears to show more extensive head streaking on the Azores individuals and so my bird looks good as far as that's concerned. A single mirror on P10 only is more common amongst the Azores population rather than from the other islands - mine had just a single small mirror on P10 and no mirror on P9. The mantle shade/colour of my bird also fits Azorean best as far as I can determine.

Azores Gull, Portimao fishing Harbour, Portugal, October 1st 2013

Below is a comparison of four different gulls, including the Azorean, photographed around the same time.

In clockwise order from top left: Yellow-legged Gull, my Azorean Gull, Channel Isles Lesser Black-backed Gull and a Scottish Lesser Black-backed Gull. Looking at these images it would appear that the mantle grey gets darker in that order. Yellow-legged Gull is said to have a Kodak Grey Scale value of 5 -7 , Azorean Gull 7-9 and Lesser Black-backed Gull 8-10.

In the close up image below of the mantles in the same order it would appear to agree, but there isn't that much difference between the Channel Isles Lesser Black-backed Gull and my Azorean Gull. This is unsurprising really as the Lesser Black-backed Gulls from the south and west of Britain are the palest of the species. The Kodak Grey Scale range of Lesser Black-backed Gull is 8-10 and Azorean Gull 7-9, so there is a good overlap.

The photographic evidence is worth looking at, but in the field the mantle colour was clearly different to the other gulls, which set it apart from the other species.

Azorean Gull L. m. atlantis

Some of the discussion about out of range Azorean Gull focuses on either hybrids or Yellow-legged Gulls from north west Spain. Well I've seen a few hybrid Lesser Black-backed Gull x Herring Gull and, although they have similar coloured mantles, they do not look like Azorean Gulls to me. As far as western Yellow-legged Gulls, well I saw plenty of wintering YLGs in Portugal including some with quite streaky heads, but none had the look of the gull that is the subject of this post. The one below had a fair amount of streaking on its head, but other than that it was a typical michahellis.

Yellow-legged Gull Larus michahellis

There appears to be plenty to learn about the gulls from the Atlantic islands, as much of what I've read points very much to a work in progress.

Click Here to read one of the reference papers.

Chocks Away

Azorean Gull

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Small Female Caspian Gull

November 11, 2013, 2:11 pm

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A smallish gull caught my eye on Saturday at Shawell A5 lagoons. Its clean white and grey plumage had me thinking Caspian Gull, but I wasn't fully convinced. Not all Caspian Gulls exhibit the full suite of characters that we perhaps expect. Its bill although parallel sided was not exceptionally long and it head despite being small didn't seem to have much of a slope to the forehead.

I hastily took some images of it whilst it bathed and these show a set of features consistent with it being an unquestionable Caspian Gull.

Bathing Caspian Gull

The photo above clearly shows the primary pattern associated with Caspian Gull. A long white tip to P10, a large white mirror on P9, a relatively small amount of black across the primaries and grey tongues which eat into the black. The narrow band on P5 is not visible in this image as the feather is hidden, but it is visible in some of the other photos. Also note the dark eyes, which on close inspection are coffee coloured. Its legs legs are pale yellow.

Caspian Gull

Having spent as much time as I have spent watching gulls in the last two years, it has become obvious that each individual gull is slightly different. It is important to keep an open mind as field guides are really helpful, but they only give an impression of what to look for. Without the photos I might well have let this one go, as the length of the observation was short and on first impression it wasn't a classic. Nothing to me suggests its a hybrid. Female Caspian Gulls are said to have weaker and shorter bills and rounded heads so this probably explains why it didn't at first glance appear to be a classic individual.

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Caspian Gull Review (Not for the Faint-Hearted)

November 22, 2013, 11:38 am

≫ Next: More First-winter Yellow-legged Gulls

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I've just carried out a review of all of the Caspian Gulls I've seen at Shawell this year. I found two amongst them that I no longer consider proven, but I'm happy to say that the others were OK.

Third-winter Caspian Gull

I followed the criteria outlined in the paper published in British Birds: From the Rarities Committee's files - Identification of Caspian Gull. Part 2: phenotypic variability and the field characteristics of hybrids, by Chris Gibbins, Grzegorz Neubauer and Brian Small.

The paper offers a point scoring system based on the authors experiences with known Caspian, Herring and hybrid Caspian Gulls. As I have photographed most of the Caspian Gulls I have found, I was able to point score them. The paper only covers adult and first-winter birds, so I had to define my own criteria for some bits for the other ages.

The first thing I did was measure the bill ratio (length divided by depth) from my photographs. The ratio of all, but the two suspect ones, was between 2.5 and 2.85 (most were nearest to 2.8). It is interesting to note that Caspian Gull bills are not exceptionally long, but because they are quite thin they appear to be long. The paper states that amongst the 100 sampled Caspian Gulls, 87% had a bill ratio of between 2.4 and 2.79 and all had a slight gonydeal angle. Only gulls considered to be hybrids had no gonydeal angle at all.

Almost all of the Caspian Gulls I have photographed showed enough to score them. Some did not show leg length, so on these I scored them as having moderately long legs and so gave them a score of 1 instead of a 0 for long legs. I did the same with any other features that couldn't be seen, so some individuals had a higher score than was perhaps the reality.

35 gulls scored within the range for Caspian Gull and so did one of the two that I am concerned about. The bill ratio appears a bit small on the one that scored OK, so I think it is best to pend it for now. The other I now consider to be most likely a hybrid.

Pure adult Caspian Gulls should score between 4 and 9 and first-winters 12 to 22.

The first-winter gull below had a point score of 20 and so should be a pure Caspian Gull - the most frequent score amongst the sampled first-winter Caspian Gulls was also 20. Interestingly , this individual had a longer primary projection than another that looked spot on because of its longer bill ratio.

First-winter Caspian Gull

The adult below was one I saw recently and that one I scored a 7.

Adult Caspian Gull

This excercise has been well worth doing because it has shown that there are perhaps fewer hybrids than might be expected.

Once the features that attract a trait score are understood this is a fairly simple task to do.

A set of record shots of Caspain Gulls allows the observer to fully check the identification at home afterwards. As far as I'm concerned photographic evidence is essential if you wish to prove the identification of these challenging gulls.

There is a great deal of studying required to ID these critters confidently, but luckily most of them do stand out in the crowd.

To read the paper on how to point score them click HERE

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