Migrants trickle through

With strong easterlies blowing there was some light visible migration going on overhead at Staines Moor this morning. 1 Common Swift heading N was my first of the year, and 3-4 Common Buzzard NE, 1 Peregrine N, 3 Common Tern E and 20+ Barn Swallows N were also seen moving through. A female Northern Wheatear in the north-west corner was the only passage migrant on the deck, but summer visitors on territory were everywhere with 3 Cuckoo (1 heard), 2 Garden Warbler, 2 Lesser Whitethroat, 18 Common Whitethroat, 7 Sedge Warbler, 2 Reed Warbler (heard), 10 Blackcap, and 7 Chiffchaff all noted.

Peregrine

Northern Wheatear

Lesser Whitethroat

Other notables seen were 3 Egyptian Geese (4th photo), 3+ Shelduck, 4 Gadwall and 15 Lapwing (a high site count nowadays).

1 of the 3 Egyptian Geese present today

I really miss the muddy pools that existed on Stanwell Moor a few years ago. Back then, passage waders such as Bar-tailed Godwit, Dunlin, Little Ringed Plover, Ringed Plover and Green Sandpiper were regular, but nowadays these pools are almost dried up and overrun with reeds and sallows, and so there's absolutely no chance of any of these beauties dropping in!

Spring male Northern Wheatears

With reports nationally of an early passage of Greenland Wheatears (Ssp. leucorhoa), I was interested to see if any of the Northern Wheatears passing through Staines Moor over the last couple of weeks could be assigned to this race based on field observations. In his article, Greenland Wheatears (Birdwatch 214: 26-27), Peter Clement points to several features that help separate leucorhoa from the nominate oenanthe in the field: larger size (up to 20%), richer orange-buff underparts extending onto the belly and down the flanks (not restricted to the throat and breast like oenanthe), a broader black tail band, longer wings (by up to 9 mm) and, on males, deeper blue-grey upperparts. However, with variation within our own birds and Icelandic birds showing an intermediate morphology, surely positive identification of birds bound for Greenland would be difficult if not impossible in the field?

At the moor the majority of male birds seen in the last two weeks have showed characteristcs associated with Greenland Wheatear. However, there was a fair bit of variation, and often the structure, posture and colour of a particular bird has appeared to change slightly depending on the light conditions and behaviour.

Click to enlarge

Figs 1 & 2 show fairly classic looking oenanthe birds - a slight, fairly compact structure with the orange-buff largely confined to the throat and upper breast and the rest of the underparts whitish. Note that the bird in fig 2 has a more clearly defined mask and supercilium, appears bulkier due to its posture and is whiter below. In comparison the birds in figs 4 & 5 show a heavier structure, richer orange-buff extending throughout the underparts and perhaps a clearer and bolder black mask and white supercilium. Fig 5 shows the same bird as fig 3 in flight - note the broad black tail band that's over a third, and almost half the length of the tail. Martin Garner suggests an interesting supporting feature for Greenland birds, where their longer wings show between 7-8 primary tips on the closed wing, compared to 6-7 on the nominate race. The bird in fig 6 clearly shows 7 primary tips (click to enlarge), which I guess could place it either camp, but doesn't rule out Greenland. To my eyes, the blue-grey on the upperparts looks pretty much the same on all these birds.

I suspect the identification of actual Greenland Wheatears can only be confirmed with biometrics, but we can at least say a bird 'shows characteristcs of' a bird from Greenland, Iceland or Fenno-Scandinavia, and it was certainly good fun trying to work it out!

More on Greenland Wheatears here:
http://www.birdwatch.co.uk/categories/articleitem.asp?item=692
http://birdingfrontiers.com/2011/04/09/greenland-wheatears/
http://steveblain.blogspot.com/2011/04/leucorhoa.html
http://peteralfreybirdingnotebook.blogspot.com/2011/04/northern-northern-wheatears.html

Oare Marshes

A change of scenery today with a late afternoon visit to Oare Marshes in Kent over the high tide. I used to come here quite a bit but its been almost two years since my last visit! There were a few summer migrants around including 5 Common Tern, 8 Yellow Wagtail, 1 Lesser Whitethroat, 1 Reed Warbler, 2 Sedge Warbler and a Cuckoo (heard). Not much of a sense of movement going on apart from a Whimbrel that dropped in to bathe on the east flood, 1 Hobby over and 5 Barn Swallow. About 200 islandica Black-tailed Godwits (1st photo) on the east flood eventually started heading off high north in small flocks (including a couple of colour ringed birds), and other birds seen include 1 male Marsh Harrier, 16 Avocet (including a pair on two eggs), 11 Redshank and 3 Little Egret (2nd photo).

Quiet evening at Staines Moor

A marked reduction in the number of migrants around this evening. A Garden Warbler along Bonehead Ditch was new for the year, but warbler numbers were much lower than of late (although I guess this is partly down to time of day) with just 2 Lesser Whitethroat, 4 Common Whitethroat, 3 Sedge Warbler, 3 Blackcap and 4 Chiffchaff in evidence. Other notables seen were 2 Cuckoo (1 heard only), 1 Hobby over S, 6 Barn Swallow, 1 Sand Martin, 6 Northern Wheatear (3 male, 3 female) at the north end, 2 Redshank and a Little Egret.

High pressure continues

With warm dry weather and largely clear skies continuing, spring passage on the ground was much reduced at Staines Moor today. 5 Lesser Whitethroat and a Cuckoo were my first of the year but both have been reported over the last few days, a female Ring Ouzel (first reported two days ago) was my third at the moor this spring and 11 Northern Wheatear (5 male, 6 female) were still at the north end.

Skywatching was better, producing 1-2 Hobby (N then S), a Red Kite over NW at 11:30 (1st photo) and 2 Common Buzzard N at midday (2nd photo) - all high up, along with 1 Yellow Wagtail over W, 8 commic tern E, 12 Sand Martin, 1 House Martin, 5 Barn Swallow and a few Skylark.

Red Kite

Common Buzzards

Skylark

Also noted were 10 Blackcap, 6 Sedge Warbler, 2 Reed Warbler (heard only), 6 Chiffchaff, 7 Common Whitethroat, 2 Cetti's Warbler (heard only), 2 Redshank, 2 Egyptian Geese and 1 Little Egret along the Colne, 4 Lapwing harassing the Carrion Crows and 6+ Shelduck. The highlight of the day for me though was this fantastic young Grass Snake (photo below). Stanwell Moor added 2 Gadwall.

Grass Snake Natrix natrix

Yellow Wagtails

The north-west corner of Staines Moor is heaving with birds at the moment. A Tree Pipit and a Cuckoo were seen before I arrived this morning, but I had to settle for 4 Yellow Wagtails (2 males and 2 females) and 15+ Northern Wheatears (one of which was singing) in amongst 15 Meadow Pipits and 15 Linnets. A commic tern over distantly, 18 Sand Martin, 5 Barn Swallow, 4 Sedge Warbler, 6 Common Whitethroat, 5 Chiffchaff, 1 Willow Warbler, 6 Blackcap, 2 Redshank, 3 Lapwing, 3 Shelduck and 1 Little Egret was the best of the rest.

More migrants

Back to Staines Moor today. A late start didn't fill me with optimism about the days birding, but this quickly changed. I had only made it a few metres along the footpath between Stanwell Moor and King George VI Reservoir when I picked up the distinctive reeling of a Grasshopper Warbler (at 11:10). Unfortunately viewing was very restricted and the bird was in an inaccessible area so I had little chance of seeing it.

On the moor itself at least 20 Northern Wheatears (12 males and 8 females) were hopping around at the northern end (4th, 5th and 6th photos), and while I was trying to work out if any 'Greenland' birds were present a female Whinchat appeared amongst them (1st photo). Minutes later a stunning male Common Redstart appeared briefly in one of the hawthorns, but despite searching I couldn't relocate it. Then things got even better when a walk around the scrub at the northern end of the moor brought me face to face with a female or perhaps 1st summer male Ring Ouzel chacking away (2nd photo). While attempting to get a few record shots another bird appeared (3rd photo)!

Also noted today were 2 Common Buzzard E, 10 House Martin, 2 Sand Martin and 15+ Barn Swallow overhead, 1 Reed Warbler (heard), 5 Sedge Warbler, 4 Common Whitethroat, 10 Blackcap, 8 Chiffchaff, 1 Willow Warbler (heard), 2 Redshank, 1 Common Snipe, 9+ Lapwing, 2 Shelduck, a Little Egret along the Colne and a Speckled Wood butterfly.