Sunday 4 September 2011

Worcestershire Redpolls and a guide to their separation



Plate 1 - Lesser Redpolls, Wyre Forest, Worcestershire, December 2005. © John Robinson

In a landlocked county like Worcestershire, the arrival of winter finch flocks undoubtedly enthuses county birders during the winter months, particularly those who find gulls and waterfowl less than inspiring. With a little effort, ten species are obtainable annually, including Brambling, Common Crossbill, Hawfinch, Lesser Redpoll and Siskin; whilst Mealy Redpoll and Twite may boost this total, though the latter has become extremely scarce locally in recent years. The planting of game crops, primarily designed to provide food and cover for Pleasant and Partridge prior and during the winter shoots, inevitably attract large winter finch flocks, particularly Linnet, Goldfinch, Greenfinch, Chaffinch, Brambling and Redpoll. These sites provide observers the best opportunely to study these birds, being confined to a relatively small area, allowing close and often prolonged, eye-level views to be obtained.

Though generally not the most colourful of our finches, Redpoll still possess a striking combination of black, buff and white plumage contrasts, whilst a male’s vivid crimson breast is no less than spectacular. Numbers may fluctuate from one winter to the next, but in years when the Silver Birch crop fails in Scandinavia, mass eruptions occur. During these periods Redpoll can become very numerous, particularly along the east coast of Britain, hence good-sized flocks often arrive in Worcestershire at this time. These flocks comprise both Lesser and Mealy Redpolls, with Arctic also a possibility and species separation can often challenge even the most experienced observers.

Redpoll has been slip into three species, Lesser Redpoll (Acanthis cabaret), Common Redpoll (Acanthis flammea) and Arctic Redpoll (Acanthis hornemanni). Additionally Common Redpoll is further divided into three races, namely Mealy Redpoll (Acanthis flammea flammea), which breed in a broad band across Scandinavia, the Baltic Republics south to east Germany and Poland, USSR and North America; Greenland Redpoll (Acanthis flammea rostrata) from southern Greenland and northern Baffin Island and Icelandic Redpoll (Acanthis flammea islandica) from Iceland. There are also two races of Arctic Redpoll, Hornemann’s Arctic Redpoll (Acanthis hornemanni hornemanni) from Canada, northern Greenland and Ellesmere Island to Baffin Island and Coues’s Arctic Redpoll (Acanthis hornemanni exilipes), which is almost circumpolar across northern Eurasia and North America. The breeding range of Lesser Redpoll extends through central Europe, with an isolated population in the Alps, to Britain, Denmark, southern Sweden and south/west Norway.

In Worcestershire, the only major influx of Mealy Redpoll occurred during the winter of 1995-96. Both Lesser and Mealy Redpoll were recorded in substantial numbers, whilst four Coues’s Arctic Redpoll were also observed in the Wyre Forest. This invasion was on a scale never experienced before nor again in the county, though was just the tip of the iceberg compared to the phenomenal total encountered nationwide. Smaller influxes were recorded during the winters of 2001/02 and 2005/06, with the majority of birds being identified as Lesser, but small numbers of Mealy were also present and another Coues’s Arctic was discovered with the Redpoll flock at Habberley Valley in January 2002.

The winter of 2007-08 was considered to be a particularly lean time for Redpoll. Nevertheless, a small number of Mealy Redpolls reached the county, including sightings from Upton Warren and the Wyre Forest. The Moors Pools at Upton Warren held the largest group of Mealies, with up to nine individuals recorded between January and April, comprising three first-winter males, two adult males, two adult females and two first-winter females. These birds were generally very confiding in the field, whilst five were trapped and examined in the hand, allowing analysis of both plumage and structure, plus direct comparisons with Lesser Redpoll, of which between 25 and 30 birds were present on the reserve.
 
Plate 2 - First-winter male Mealy Redpoll, Merrilands Farm, Worcestershire (left) & female Lesser Redpoll, Wyre Forest, Worcestershire January 2006 (right). © Andy Warr & John Robinson
 


Plate 3 - Adult male Mealy Redpoll, with adult male Lesser Redpoll, Williamthorpe, Derbyshire, 5th November 2005. © Steve Mann

The comparisons above depict the two extremes in plumage tone, plus size and structural differences encountered between Mealy and Lesser Redpoll. On the top birds, note the frosty appearance of this first-winter male Mealy, compared to the darker brown and buff plumage hues seen on this Lesser, whilst size and structural differences between the bottom adult male Mealy and Lesser are obvious. Unfortunately the separation of these two species is far more complex then these individuals would suggest. Plumage differences, particularly between female Mealy and Lesser can be slight and to confuse matters further, some may appear similar in size and structure to Lesser in the field, though size differences are noticeable when direct comparisons are made in the hand. It is therefore feasible to suggest that many female type Mealies are mistakenly attributed to Lesser.

 
Plate 4 - Adult female Mealy Redpoll (left bird) first-winter male Mealy Redpoll (right bird) Upton Warren, Worcestershire, March 2008. © Brian Stretch & Fergus Henderson

Note the size difference between the two Mealy Redpolls pictured above, trapped and ringed at Upton Warren in early March 2008, the adult female being notably less bulky than the first-winter male. Size variations occur in both sexes, so on biometrics, particularly body, wing and tail length, there is considerable overlap, though structurally males appear bulkier, giving the impression of a larger bird. Wing measurements on males range from 70-81mm and females 68-79mm. The first-winter male trapped, possessed a wing length of 75mm, whilst the female alongside was measured at 72mm and though this male has a midrange wing length, its body size and structure suggests it to be a bird at the upper size limit of Mealy, whilst the lower size limit has almost been reached by this female. The frosty appearance of the male contrasts with the darker brown and buff plumaged female, who’s darkly streaked flanks are also far more prominent. An obvious dark shaft is running down the centre of the longest central undertail-covert of this male, whilst to the sides, the dark tips to the shafts on the two longest outer coverts are just visible. On this female the undertail-coverts appear totally unmarked. Assessing the extent of streaking on the undertail-coverts is problematic, as the overlapping inner coverts usually conceal at least half of the longest central and an even greater proportion of the side coverts and as on the female pictured above, this streaking may be hidden entirely. As these dark shafts are broadest at the base, a true assessment of their width in the field is not possible. The width of the shaft on the longest undertail-covert can be a useful aid when separating Mealy from Arctic in the hand. On Mealy, it is usually 3-5mm wide, but exceptionally as narrow as 2mm, whilst on Arctic it is entirely absent or graduates to a maximum of 2mm. The number of streaked undertail-coverts varies considerably throughout the species range of Redpoll, even on Arctic, so this feature may be of little benefit when ascertaining a bird’s true identity. The visible markings on the undertail-coverts of all the Lesser Redpolls pictured below fall within the range encountered on Mealy, whilst the two Mealies and right hand Lesser have markings not dissimilar to Arctic.

Plate 5 - Mealy Redpoll - Mealy Redpoll - Lesser Redpoll - Lesser Redpoll - Lesser Redpoll - Lesser Redpoll - Arctic Redpoll



Redpoll identification guide

Lesser Redpoll was designated full species status from Common Redpoll by the British Ornithologists Union in 2000, but at present, many field guides fail to cover their separation from Mealy in any great detail. The following article on Redpoll identification, particularly when dealing with the separation of Mealy from Lesser, is prominently based on photographed individuals encountered at Upton Warren and the Wyre Forest during the first winter period of 2008, though county birds from past and more recent years and individuals from localities outside Worcestershire have also been included. The plumage characteristics described cover the period when Redpoll is most likely to be encountered in Worcestershire, being between August and May for Lesser and from October to April for Mealy, so both fresh and moderately worn plumaged birds have been included. Not included in this article are descriptions of the Arctic Redpoll complex, as this species is adequately dealt with in field guides, though comparisons and plumage features of first-winter/female Coues’s Arctic Redpoll have been covered, as these birds are similar in appearance to some pale first-winter male Mealy Redpolls. Adults do a complete post-breeding feather moult and juveniles a partial moult between July and October, which on juveniles include body feathers, most if not all the wing-coverts and rarely one or two tertials and inner pairs of tail feathers. The shape and particularly condition of the tail feathers can be a useful guide to the ageing of Redpoll during the winter months, as all are fresh on adults, so appear clean edged and generally more rounded at the tips, whilst juvenile tail feathers are pointed and by late winter, clearly more worn and ragged at the tips than those of adults. Note below, that all juvenile tail feathers have been retained on the first-winter bird, pictured top left and middle, the central pairs being pointed, with the outer feathers heavily abraded, whilst the top right first-winter has moulted two inner pairs, which appear rounded and contrast with the remaining heavily abraded juvenile feathers. Conversely on these two adults (bottom) the feathers are more rounded and fresh tipped. It is important to note that the tail feathers of first-winter birds during the autumn and early winter may appear reasonably fresh tipped and there is a degree of overlap in tail shape between adult and first-winter, so ageing some individuals during this period can be particularly difficult, even in the hand.
 
Plate 6 - Tail feathers of Redpoll, first-winters (top) adults (bottom). All first-winters and left adult taken in early March, right adult in early February
 
A guide to bird topography has been included to familiarize readers with all of the feather tracts and plumage markings mentioned in the text.
 
Plate 7 - Topography chart
 
Adult male Mealy & Lesser Redpoll
Of all the taxons of Redpoll, Mealy shows the greater diversity in plumage, so when Mealies arrive in Britain, variations in colour tones and markings can be considerable. Some adult males have acquired rosy/pink-tinted breast, cheeks and rump, lost darker tawny tones to the upperparts and developed pure white wing-bars as early as November, whilst others retain their darker, fresh plumage into February, like the Upton Warren bird depicted below (right). Presumably, this is the result of an individuals progressive state of feather wear, rather than plumage variations across its geographical breeding range, with the most north/easterly Scandinavian, northern Baltic and Russian breeding populations migrating far greater distances to reach our shores, so prone to wear and bleaching far sooner than a shorter-distance migrant from a south/western Scandinavian population. As the two adult males at Upton Warren didn’t develop an obvious bright crimson breast until late February, plus they still retained a slight buff hue to the wing-bars suggests these individuals originated from a south/western breeding population.
A fresh plumaged adult male Mealy can look surprisingly dark compared to a first-winter male (see pictured below) so on plumage, apart from the extensively white back and rump, may appear similar to Lesser. The rear crown and nape are tawny or buff/brown, evenly streaked dark brown and black and the sides of the neck streaked paler buff or buff/white. Dull black is quite restricted around the base of the bill, including the bib, the lores are dull black, there is pale greyish/buff diffusion to the supercilium, ear-coverts and cheeks, with the latter sometimes tinged rosy/pink. The mantle and scapulars are tawny/brown, broadly streaked dark brown/black, one or two pairs of whitish or pale buff lines run down the centre of the mantle, the extensively white back is moderately streaked black, tawny and buff and the pale rump is tinged buffish/pink and noticeably less streaked than the back. The flanks and sides of the breast are tinged buff, strongly marked with dark brown streaking, the wings are black/brown, with buff/off-white tips to the median and greater coverts (wing-bars) and similarly coloured fringes to the tertials and primaries. A rosy/pink hue may be just visible on the breast, but is often concealed, as on the Upton Warren bird, by the broad whitish tips to the body feathers, which eventually abrade, revealing this colouration.


Plate 8 - First-winter male Mealy Redpoll, Upton Warren, Worcestershire, 2nd March 2008 (left) & adult male Mealy Redpoll, Upton Warren, Worcestershire, 10th February 2008. © Andy Warr & Brian Stretch

 The adult male Mealy below, photographed in early November 2005, this being a winter when good numbers were present in the country, has plumage far more advanced than the Upton individual featured above. It has already developed an obvious rosy/pink hue to the rump, cheeks and breast, the initial tawny colouration to the outer mantle has faded to brown/buff and the un-sheltered outer medium and inner greater coverts have bleached to white, though off-white and buff tips are still visible on a few of the outer greater coverts. The extent of both wear and bleaching on this individual so soon after the post-breeding moult, suggests this to be a bird from north/eastern Europe or beyond.


Plate 9 - Adult male Mealy Redpoll, Williamthorpe, Derbyshire, 5th November 2005. © Steve Mann

 
On the fresh plumaged adult male Lesser Redpoll (pictured below) the buffish/brown tramlines running down the centre of the mantle, tend to show little contrast with the outer mantle and the ground colour to the back is also similar to the latter, heavily streaked tawny, brown and buff, with little or no white showing through. The quite heavily streaked rump is darker than on Mealy, through the colouration of the head, outer mantle, scapulars and wing-bars can be very similar. As on Mealy, a varying amount of rosy/pink may be present on the cheeks, rump and breast, depending on the individual's state of wear.
 

Plate 10 - Adult male Lesser Redpolls, Wyre Forest, Worcestershire, January 2008 (left), December 2005 (right) © John Robinson

 
Adult male Mealies transformation into full breeding plumage is entirely due to feather wear. At this point the crimson breast, cheeks and rump develop further, crimson on the underparts being less extensive than on Lesser and usually restricted to the throat, breast and upper flanks, plus buff tips to the median and greater coverts and fringes to the tertials and primaries begin to whiten, though the wing-bars on some individuals may have long since bleached to white. Dark streaking to the sides of the breast and flanks and the strong tawny hue to the scapulars and outer mantle begin to fade, the latter becoming light brown, buff, grey and white, with dark streaking on the feather centres strongly contrasting against the paler ground colour to the upperparts. The Upton Warren bird depicted below has already lost all streaking from the sides of the breast, but still retains a few buff streaks to the flanks and the brown scapulars, still contrast strongly with the extensively white back and central mantle stripes. The ground colour to the outer mantle, though still darker than the back and central mantle has faded considerably, with light brown, buff and off-white replacing initial darker brown tones. Caution is required when assessing the extent of white on the back, as depending on the bird’s stance; much may be concealed behind the closed wings. The rear crown and nape are pale grey, lightly streaked brown/buff; buff hues are absent from the flanks and sides of the breast, whilst the ear-coverts, sides of the neck, and supercilium appear frosty grey. Buff/off-white fringes are still visible on the tertials and primaries, whilst the wing-bars, which are only just visible on the bottom photographs, still retained a slight buff hue throughout, so showed little change from the wing-bars depicted on the fresher plumaged adult Mealy featured earlier.



Plates 11 - Adult breeding plumaged male Mealy Redpoll, Upton Warren, Worcestershire, mid & late March 2008. © Andy Warr


 
Breeding plumaged adult male Lesser Redpolls (pictured below) are generally darker and more heavily streaked throughout than equivalent plumaged Mealy. Crimson on the underparts is far less restricted than that of Mealy, extending down to the sides of the belly and lower flanks, with brown/buff flecking retained on the flanks, rump, plus to the sides of the breast. Strong tawny, to rusty/brown is retained on the upperparts, with dark streaking sharply defined on the rear crown, nape, scapulars and mantle; the central mantle, back and rump become paler with wear, though the latter two are more extensively dark streaked and white ground colour less extensive than seen on adult male Mealy, whilst the rear crown, ear-coverts, supercilium and sides of the neck may acquire a lighter, frosted appearance. Tips to the outer medium and inner greater coverts have usually bleached to off-white, though tawny/buff tips are clearly visible on the outer greater coverts.


Plate 12 - Adult male Lesser Redpoll, Upton Warren, Worcestershire, 29th March 2008. © Andy Warr

 
Plate 13 - Adult breeding plumaged male Lesser Redpolls Wyre Forest, Worcestershire, 21st March 2008 (top) © Andy Warr, and Wyre Forest, 8th April 2006 (bottom) © John Robinson

 
When an adult male Mealy is observed alongside Lesser Redpoll, its greater size and bulk is usually obvious, though with isolated birds, this is more difficult to assess. With lone birds, body structure, as well as plumage, is a useful guide when separating these two species. The photographs below depict Mealy (top) and Lesser (bottom), where the following structural differences are evident. Note the overall bulk, broad shouldered and bullnecked appearance of this Mealy, compared to the slimmer profiled Lessers. The head and breast of Mealy appear broad, front on, with the latter having a puffed out appearance, whilst on Lesser, the face and breast appears slimmer and more streamlined. From behind, the body of Mealy, compared to Lesser, appears more rounded, with bulging breast and flank feathers clearly more visible to the sides of the wings. A bird's posture may be influenced by weather conditions, particularly on cold winter mornings. Body feathers may be puffed out; trapping warmer pockets of air sustained by body heat, so consequently, Lessers may adopt a posture similar to Mealy, but this is soon lost once an individual becomes more active. This Mealy was photographed on a warm March afternoon, so portrays the standard posture for this species.



Plate 14 - Adult male breeding Mealy Redpoll, Upton Warren, Worcestershire, March 2008. © Andy Warr


Plate 15 - Adult male breeding Lesser Redpolls, Wyre Forest, Worcestershire. © John Robinson
 
 
First-winter male Mealy Redpoll & Coues’s Arctic Redpoll
Typically, Mealy Redpolls arrive in Worcestershire during December and January, by which time the plumage of a first-winter male can often be very frosty in appearance, with tawny/brown hues restricted to the nape, sides of mantle and scapulars, all diffusely streaked black/brown. The supercilium is white, the ear-coverts, neck and throat are tinged buff when fresh, but quickly wear to a light grey wash, the extent of black on the lores, plus above the bill increases with wear, whilst the black bib is extensive. The fringes to the tertials, uppertail-coverts, plus wing-bars are pure white and usually a few shorter juvenile outer greater coverts are retained, as on the individual pictured directly below. The central mantle, back and rump are snowy white, the latter two variably streaked black/brown and a pink flush may also be visible on the shorter uppertail-coverts, rump and cheeks, but is usually absent from the throat and breast. All three first-winter males present at Upton Warren, showed varying densities of pink on the shorter uppertail-coverts and rump, but this was absent from the cheeks and breast on all. A buff hue is often present on the sides of the breast and upper flanks, marked with variable amounts of diffused brown/black streaking, which usually extend well onto the lower flanks.



Plate 16 - First-winter male Mealy Redpolls at Upton Warren, Worcestershire, March 2008. © Brian Stretch, Peter Walkden & Andy Warr

 
Plate 17 - First-winter male Mealy Redpolls (left) Wyre Forest, Worcestershire, January 2008. © John Robinson (middle & right) Wadborough, Worcestershire, January 2006. © Andy Warr

 
Plate 18 - First-winter male Mealy Redpolls Williamthorpe, Derbyshire, 5th November 2005. © Steve Mann
 
The photograph below depicts a first-winter male Mealy Redpoll alongside a Lesser Redpoll and clearly shows the differences in size, structure and colouration. Particularly note the broad headed and bullnecked appearance of this Mealy.


Plate 19 - First-winter male Mealy Redpoll, with Lesser Redpoll, Lineholt, Worcestershire, January 2nd 2009. © Andy Warr


Some individuals can show very limited dark streaking on the flanks and rumps like the Upton Warren bird pictured below (left) and are very similar in appearance to Coues’s Arctic Redpoll (right). Birds like this require careful scrutiny before assigning to either species and shorter-billed, straighter culmen (top ridge of the bill) Mealies are more difficult to separate from Coues’s Arctic, though feather structure around the base of the bill on Arctic appears sufficiently different from a shorter billed Mealy, if close views are obtained. Note on the Upton bird that though a portion of the rump appears unmarked from a distance, darker diffused marks are clearly visible in this area at close range, but still well within the range of some first-winter/female Coues’s Arctic Redpolls.


Plate 20 - First-winter male Mealy Redpoll, Upton Warren, Worcestershire, March 2008 & first-winter Coues’s Arctic Redpoll, Sweden, November 2004 © Fergus Henderson & Mikael Nord

 
As mentioned above, the appearance of the bill is one feature, which helps separates Mealy from Arctic. On the comparison below, note on these three Mealies (top), that the bills appear reasonably long and visually broad at the base, with only a small proportion of the bill base hidden by feathering, whilst the culmen is often slightly convex, especially towards the tip, this feature being less obvious on the bird to the left, whilst an example of a smaller-billed individual is depicted to the right. Conversely on Coues’s Arctic the bill appears short and stubby in proportion to head size, due to loose feathering, which extends out from the lores and extensive fluffy nasal bristles, which conceal a large proportion of the bill base, on the upper mandible. Though this feathering gives the impression of a short and stubby bill, in reality, measurements of bill length, depth and breadth overlap with Mealy. The culmen is also straight on Arctic, even towards the tip. Also note the differences between the size and position of the eye. On Mealy the eye appears larger and more central in the face, compared to the smaller, set forward eye of Arctic. The head being proportionally larger and even more bullnecked on Arctic, rather than a smaller eye causes this impression.



Plate 21 - Mealy Redpolls, Upton Warren, Worcestershire, March 2008 (top left) © Peter Walkden (top middle) © Fergus Henderson. Mealy Redpoll, Williamthorpe, Derbyshire 5th November 2005 (top right) © Steve Mann Coues’s Arctic Redpoll, Aberlady Bay, East Lothian, December 2005 (bottom left) © Ray Wilson, Sweden, November 2004 (bottom right) © Mikael Nord.

 
First-winter and adult female Coues’s Arctic Redpolls, are most likely to be confused with Mealy, as body size and structure is similar, plus dark streaking is generally more prevalent on the flanks and on some individuals, particularly first-winter females, a faintly streaked rump my also be present. On the comparisons below, note how similar the pattern of flank streaking is between the Upton Mealy (centre) and these two first-winter/female Coues’s Arctic’s. An extensive white rump and back is obvious on all these birds, though the rump appears totally unmarked on the left hand Arctic, whilst the colouration of the mantle and scapulars are also very similar, if not slightly darker on the Arctic pictured to the right. The Upton Mealy demonstrates that first-winter males cannot be separated from Arctic on plumage alone, indeed some Arctic’s are far greater marked on the flanks and rump, than the individuals depicted below and highlights the relevance of structural differences such as the bill. Coues’s Arctic in fresh plumage shows a cream hue to the supercilium, ear-coverts, neck, throat, upper breast and wing-bars, though this colouration will quickly fade to greyish/white, then pure white. A pink hue may be present on the smaller uppertail-coverts on first-winter males, whilst on both first-winter and adult females pink is entirely absent. The dark bib is rather small and dull black or sooty grey, so more similar to the bib of Lesser, than Mealy in appearance.

Plate 22 - First-winter/female Coues’s Arctic Redpoll, Aberlady Bay, East Lothian, December 2005 (top & bottom left, centre insert) © Ray Wilson, first-winter male Mealy Redpoll, Upton Warren, Worcestershire, March 2008 (top & bottom middle) © Andy Warr & Fergus Henderson and first-winter Coues’s Arctic Redpoll, Sweden, November 2004, (top & bottom right) © Mikael Nord
 
Observations made of the Coues’s Arctic Redpoll at Habberley Valley, Worcestershire in 2002, revealed a significant difference in feeding behaviour from both Lesser and Mealy Redpoll, when feeding on the catkins of Silver Birch (Betula pendula). Whilst Lesser and Mealy extracted seeds directly from the hanging catkins, the Arctic removed the entire catkin with its bill, carried it to a horizontal branch and proceeded feeding on the seed heads whilst securing the catkin with its feet against the branch.

First-winter male Lesser Redpoll
First-winter male Lesser Redpoll is darker tawny/brown and more heavily dark streaked on the upperparts than first-winter male Mealy, plus the wing-bars are tawny/buff to buff/off-white and the fringes to the wing-coverts, tertials, primaries and secondaries tawny/buff. With feather wear, the ground colour of the lower back and rump, plus the central mantle may whiten, as depicted on the two individuals below, but generally retain tawny/buff hues to the fringes of the uppertail-coverts and lower rump. Crimson/rosy-pink may be present on the cheeks, throat and breast by late winter/early spring, though usually less extensive than on adult male, whilst in fresh plumage, this colouration is absent entirely, so these individuals are indistinguishable from female birds.


Plate 23 - First-winter male Lesser Redpolls, Wyre Forest, Worcestershire, 31st March 2006 (left), 19th March 2008 (right) © John Robinson

 
First-winter female, fresh plumaged first-winter male and adult female Mealy and Lesser Redpoll
As mentioned earlier, adult female, first-winter female and fresh plumaged first-winter male Mealy Redpolls can sometimes be difficult to separate from Lesser Redpoll with certainty in the field, as differences in size, structure and plumage can be subtle, the latter especially when Lessers become paler with wear. It is important to note that a moderately worn Lesser can display a white ground colour to the rump, back and central mantle and some first-winters may acquire almost complete off-white wing-bars. Despite this, it may be possible, if excellent views are obtained, to identify most female Mealies, by a combination of plumage features, which are highlighted in the photographs below.


Plate 24 - First-winter female Lesser Redpoll (top left) adult female Mealy Redpoll (top right & middle) Upton Warren, Worcestershire March 2008. © Andy Warr & Fergus Henderson. First-winter female Mealy Redpoll (bottom) The Knapp, Worcestershire, March 4th 2011. © Fergus Henderson.

 
Note on the Mealies pictured above (all but top left insert) and below (bottom inserts) photographed in early and mid March, the conspicuous white tips to the medium and greater coverts, which contrast strongly with very dark, almost black centres to the coverts, tertials, primaries and secondaries, though buff is visible on the side fringes to the wing-coverts and flight feathers. Generally on Lesser, the wing-bars are Buff/off-white, graduating to yellowish/buff towards the outer greater coverts, so contrast less against the dark wings, though note on this first-winter female Lesser, photographed in late March, above (top left) and below (top) that all the tips to the greater coverts, appear off-white, though off-white tips to the outer medium coverts, contrast with the grey/buff tips to the inner medium coverts, these being barely visible on the closed wing. A juvenile’s partial feather moult begins soon after fledging, so the earliest birds are already replacing all their median coverts and a variable number of inner greater, if not all greater coverts by late July, early August. By late winter/early spring the tips to these coverts on Lesser Redpoll have often bleached to off-white or white, particularly the more exposed inner greater and the outer medium coverts. It is highly improbable that Lesser Redpoll would ever possess pure white wing-bars throughout when examined in the hand, though may appear to do so when viewed in the field, whilst a first-winter Mealy may have retained a few buff tipped juvenile outer greater covert, though still posses white tips to all the medium coverts.


Plate 25 - First-winter female Lesser Redpoll (top) adult female Mealy Redpoll (bottom) Upton Warren, Worcestershire, March 2008

 
Note differences in the colouration of the lower rumps and uppertail-coverts on the Lessers and Mealies pictured below. Through the ground colour of the backs and upper rumps are white on all these birds, the feather fringes to the uppertail-coverts and lower rumps on these Lessers (birds to the left) are tawny/buff, so appear similar in colour to the mantle and scapulars, whilst on these Mealies, the fringes are off-white/buff, so show less contrast with the upper rump and back and are far paler than the mantle and scapulars. Both adult female Mealy and Lesser may acquire a hint of rosy/pink to the rump and lower cheeks, plus occasionally a slight wash to the breast.


Plate 26 - First-winter female Lesser Redpoll (top & bottom left) & adult female Mealy Redpoll (top & bottom right) Upton Warren, Worcestershire March 2008. © Andy Warr

 
The head of Mealy looks pale, compared to the darker brown toned head of Lesser, as depicted in the photos below. Mealy possesses a uniformly whitish supercilium, submoustachial-stripe and throat, all being only slightly tinged buff, plus white is quite extensive on the upper ear-covert, below the eye. The remaining portion of the ear-covert contrast with the aforementioned, being lightly streaked in shades of white, buff and light brown. The black forehead and lore are particularly bold on this individual, but can appear duller on some birds, due to the presence of white flecking, whilst the solid black chin (bib) is large and on naturally posed birds appears long, so similar in appearance to the black bib of a first-winter male Mealy. In contrast, the supercilium on Lesser is yellowish/buff, being diffusely streaked tawny/brown, the submoustachial-stripe is also yellowish/buff, a narrow pale eye-ring contrasts with the ear-coverts, which are tawny/buff throughout, so generally plainer and less contrasting than the streaked ear-coverts seen on Mealy, whilst the rear crown and nape are usually a darker tawny/brown, but not necessarily more heavily streaked. The forehead and lore are dark brown, but as on Mealy may be mottled with pale flecking and the dark brown bib is less extensive. Usually the throat and breast are strongly tinged yellowish/buff or yellowish/brown, compared to whitish/buff on Mealy. The bill of Mealy generally appears long and robust, compared to the shorter, stubby bill of Lesser, though there is some overlap between shorter billed Mealies and the longest billed Lessers.


Plate 27 – Female Lesser Redpoll (left) & adult female Mealy Redpoll (right) Upton Warren, Worcestershire, March 2008. © Andy Warr

 
Fresher plumaged adult female and first-winter Mealy Redpolls generally show stronger buff colouration to the face, throat, breast, flanks and undertail-coverts than birds encountered during the late winter and spring, plus a less distinct dark chin patch may be present on a first-winter, due to concealment by pale feather fringes, which soon abrade, revealing back beneath. The pale supercilium, submoustachial-stripe, throat and fringes to the uppertail-coverts are uniformly tinged buff, but will quickly whiten with wear and the buff or tawny/buff colouration to the sides of the breast and flanks, being heavily streaked dark brown and black, contrast strongly with the pure white belly. The whitish/buff central mantle stripes, though pale, may contrast less with the sides of the mantle and scapulars and the pale, buff tinged rump, have dark streaking generally more prevalent than on moderately worn females. The individuals depicted below are all first-winters, probably females and note how a few buff tipped outer greater coverts are visible on the top and left hand birds, though overall, the wing-bars are far whiter than Lesser would possess so early in the year. Black is quite restricted on the lores and around the base of the bills and the dark bibs quite indistinct on these birds. Note the white, buff and light brown streaking to the ear-coverts, plus the longish, robust bills on most of these birds, though the bird depicted bottom left and middle is a smaller-billed individual. The crown patch is tinged orange and yellow on the top individual, being a feature quite regularly encountered on both first-winter birds and adult females (see later in article).


Plate 28 - First-winter (probably female) Mealy Redpolls, Wyre Forest, Worcestershire, January 2008. © John Robinson

 
The two Mealy Redpolls depicted below are both fresh plumaged first-winter birds, photographed in Germany in early October. Such individuals are impossible to sex so soon after completing post-juvenile moult, as the plumage of first-winter male is darker when fresh, so identical to that of female and the pinkish wash to the rump seen on first-winter males is usually lacking until mid winter. Note on the top individual the indistinct pale eye-ring, which only contrast slightly with the pale supercilium and ear-coverts directly below the eye. The crimson forehead is patchy and pale feather fringes conceal much of the darker feathering around the base of the bill, on the lore and chin. The bottom bird has slightly more advance plumage, with a fuller crimson forehead and paler ear-coverts, while pale buff/whitish fringes are clearly visible on the uppertail-coverts. Both individuals have moulted their medium and most the inner greater coverts, which appear broadly tipped off-white, but still retain a few worn and narrowly buff fringed juvenile outer greater coverts.



Plate 29 - First-winter Mealy Redpolls, Helgoland, Germany, October 13th 2010. © Detlef Gruber

 
The photographs below taken in late March, depict a first-winter female Mealy Redpoll (top), compared to an adult female Lesser (bottom). This Mealy has been aged as a first-winter due to the pointed and abraded tips to the tail feathers and heavily abraded fringes to the tertials, through no buff tipped juvenile outer greater coverts have been retained. Structurally, this bird appeared a little larger and bulkier than the Lessers observed feeding alongside and note how it possesses all the plumage features consistent with Mealy, such as whitish supercilium, submoustachial-stripe and fringes to the longest uppertail-covers, extensive white patch below the eye and indistinct eye-ring, plus pure white wing-bars throughout. The female Lesser Redpoll depicted, which is an adult, going by the relatively rounded and fresh tipped tail feathers, plus broad pale fringes to the tertials, shows all the classic plumage markings for this species, including yellowish/buff supercilium, submoustachial-stripe, throat and breast, plain tawny/buff ear-coverts, narrow eye-ring, plus yellow/buff tips to the medium and greater coverts.


Plate 30 - First-winter female Mealy Redpoll (top) female Lesser Redpoll (bottom) Wyre Forest, Worcestershire, March 2008. © Andy Warr

 
The first-winter Mealy Redpoll picture below is probably a female due to the strong buff colouration throughout the flanks and to the undertail-coverts and clearly shows how similar in size and structure some individuals can be to Lesser. The Lesser pictured is a fresh plumaged adult male, which can be marginally larger and more bulky than female Lesser.


Plate 31 - First-winter (probable female) Mealy Redpoll (left) & male Lesser Redpoll (right) Wyre Forest, Worcestershire, January 2008. © John Robinson

 
Plate 32 - First-winter (probable female) Mealy Redpoll, Wyre Forest, Worcestershire, January 2008. © John Robinson

 
Occasionally a Lesser Redpoll will appear particularly pale when viewed from front-on, where brown and buff hues are reduced on the head and underparts. Such a bird is depicted below and these paler individuals can certainly stand out amongst a flock of Lesser Redpolls and may be confused with Mealy, though the plain ear-coverts, a narrow, pale eye-ring contrasts with the ear-coverts, plus the colouration of the upperparts and wing-bars generally match that of classic Lesser Redpoll.


Plate 33 - Lesser Redpoll, Lineholt, 2nd January 2009 © Andy Warr

 
As would be expected, there are always a few individuals that show characteristics of both Mealy and Lesser and one such example is depicted below. At first glance, its paleness suggests Mealy, though structurally it recalls Lesser, appearing slight in build, with a large eyed expression and a short, stubby bill. The whitish supercilium and fringes to the uppertail-coverts, plus the extensive white patch below the eye are features consistent with Mealy, whilst the yellow/buff hue covering a large proportion of the wing-bars suggest this bird to be a particularly pale Lesser. The ear-coverts also appear streaked, but this could be the result of sodden feathering after bathing. This individual is clearly adult, due to the pristine broad and obviously rounded tips to the tail feathers and broad pale-fringes to all the tertials. An adult female Mealy should ideally possess pure white wing-bars throughout, whilst structurally it appears too slight for adult male Mealy, plus lacks an extensive white ground colour to the back. This individual emphasises the importance of not assigning a bird to Mealy unless a full list of plumage criteria has been secured and it is best to leave some birds as unidentified Redpoll species.

Plate 34 - Redpoll sp, Wyre Forest, Worcestershire, 12th February 2008. © John Robinson
 
Heavily worn Redpolls
Though Lesser is the only species of Redpoll likely to be encountered in Worcestershire during the late breeding season, it is interesting to note, that on heavily worn birds of all three species, the pale fringed feathering to the upperparts have largely worn off, so become predominantly streaked blackish/brown, with narrow grey/white flecking throughout, the latter most obvious on the rump. The underparts on both Lesser and Mealy become quite dusky, though pure white is sustained by Arctic, plus the pale fringes to the greater and median coverts have largely abraded, so wing-bars appear very narrow or may be absent entirely.

Plate 35 - Arctic Redpoll (left) Mealy Redpoll (right) both moulting adult males, Pasvik, Norway, August 2015. © Andy Warr

Variations in the cap colour
First-winters and female Lesser, Mealy and Arctic Redpolls generally show a crimson cap, with varying degrees of brightness, though it is not uncommon for some to show orange, copper, yellow, even brownish caps, or any combination of the aforementioned. These colour variations are exceptionally present on adult male Lesser and Mealy, though is reported as common in captive bred birds, but more regularly encountered in adult male Arctic.

Plate 36 - Redpolls, Wyre Forest, Worcestershire. © John Robinson
 
Summery of the salient features of Mealy Redpoll 

Adult male (fresh)
 · Large and bulky, compared to Lesser Redpoll.
· Whitish/buff central mantle stripes and tawny/brown outer mantle and scapulars, broadly streaked dark brown/black.
· Extensive white back, moderately streaked black, tawny and buff.
· Whitish rump, tinged buff/rose, lightly streaked tawny/buff.
· Buff/off-white wing-bars.
· May show traces of rosy/pink on breast and lower cheeks.
· Possibly confusable with Lesser Redpoll.

Adult male (moderately worn into breeding plumage)
· Large and bulky, compared to Lesser Redpoll.
· Obvious white central mantle stripes and paler outer mantle.
· Extensive white back, moderately streaked black, tawny and buff.
· Bright crimson rump, lightly streaked brown/buff.
· Buff/off-white wing-bars may still be present, but bleached to white on many individuals.
· Bright crimson on the cheeks and breast, not obviously extending down the flanks, as on Lesser.
· Frosted on the face, sides of the neck and nape.
· Minimal dark streaking on the sides of the breast and flanks.
· Unlikely to be confused with either Lesser nor Arctic Redpoll.

First-winter male (worn)
· Large and bulky, compared to Lesser Redpoll.
· Overall very pale appearance.
· Pure white central mantle stripes, back, rump (may be tinged pink), supercilium and wing-bars, though a few juvenile buff tipped outer greater coverts may have been retained.
· Minimal dark streaking on the back and rump.
· Extensive black bib.
· Grey wash to the to the face, neck and throat
· Confusable with Coues’s Arctic Redpoll.

Adult female and first-winter female (moderately worn, late winter/early spring)
· Some slightly, others notably larger than Lesser and structural differences can often be negligible.
· White wing-bars throughout on adult, a few buff tipped outer greater coverts may have been retained on first-winter birds.
· Off-white/buff fringes to the uppertail-coverts and lower rump, showing only slight colour contrast with whitish upper rump and back, though far paler than mantle sides and scapulars.
· Whitish supercilium, sides to the neck, throat and breast, only slightly tined buff, extensive white patch below the eyes, indistinct eye-ring, streaked ear-coverts and extensive black bib.
· Some individuals may be difficult to separate from Lesser Redpoll in the field.

Adult female and first-winter female/male (fresh, after post-breeding moult)
· Much as moderately worn female, but sometimes darker streaking on ear-coverts and less distinct dark chin patch on some fresh first-winters.
· Pale supercilium, submoustachial-stripe and throat uniformly tinged buff.
· White or off-white wing-bars throughout, or a few buff tipped outer greater coverts retained on first-winters.
· Some individuals may be difficult to separate from Lesser Redpoll in the field.


Plate 37 - First-winter male Mealy Redpoll, Upton Warren, Worcestershire, 6th February 2008. © Des Jennings

 
Wing length & weight of Mealy & Lesser Redpolls trapped at Upton Warren in 2008
 
Mealy Redpoll Age & Sex, Wing & Weight
First-winter male 75mm 14.4g
Adult female 72mm 12.0g
Adult female 71mm 13.0g
First-winter female 74mm 12.5g
First-winter female 74mm 12.2g
The minimum wing length of Mealy Redpoll is 70mm for male and 68mm for female.

Lesser Redpoll
Age & Sex, Wing & Weight
Adult Male 72mm 12.1g
Adult Male 70mm 12.2g
Adult Male 73mm 12.5g
Adult Male 72mm 12.2g
Adult female 68mm 10.9g
Adult female 67mm 10.9g
Adult female 73mm 11.2g
First-winter female 66mm 9.9g
First-winter female 66mm 10.2g
First-winter female 69mm 10.4g
First-winter female 69mm -
First-winter female 70mm 11.2g
First-winter unsexed 70mm 11.6g
First-winter unsexed 69mm 11.5g
First-winter unsexed 69mm 11.0g
First-winter unsexed 71mm 12.0g
First-winter unsexed 72mm 10.9g
First-winter unsexed 71mm 7.9g
The maximum wing length of Lesser Redpoll is 74mm for male and 73mm for female.

Other races & variants of Common Redpoll

Mealy Redpoll variant ‘holboellii’
A long-billed form of Mealy, with crimson breast on average slightly deeper in tone, but overall plumage features as on nominate flammea. Breeds in eastern Siberia (common), western Siberia and north/eastern Eurasia (far less common) occurs side-by-side with northern range of nominate flammea.
Wing length: Male 73mm – 83mm, female 70mm – 79mm.


Plate 38Mealy Redpoll ‘holboelli’ Pasvik, Norway, August 2015. © Andy Warr

North-western Redpoll
The collective term for Greenland and Icelandic Redpoll (see below).

Greenland Redpoll (rostrata)
Generally the largest and darkest race of Common Redpoll, with a deeper and wider base to the bill than Mealy, being notably more convex on the culmen and gonys. Plumage colouration and extent of dark streaking on the upper and under-parts very similar to Lesser Redpoll, but mantle and scapulars a paler buff/brown, so less tawny than seen on Lesser. The rump is buff to off-white, with broad black streaking throughout, buff is prominent on the breast and flanks, whilst fringes to the tail feathers, tertials and tips to the greater and median coverts much the same as on Mealy, buff when fresh, white when worn. Black very extensive around the base of the bill and on the throat, plus on average a paler and less extensive crimson breast than seen on Mealy. Wing length: Male 74mm – 86mm, female 74mm – 85mm.

Icelandic Redpoll (islandica)
Very similar to Greenland Redpoll in plumage and size, though generally slightly smaller, plus bill on average slightly shorter and less convex and upperparts, particularly the rump, tends to be paler. Paler birds co-exist alongside darker Icelandic Redpolls and are far more variable in size, with plumage colouration and bill size on average more similar to Coues’s Arctic Redpoll. The true status of these pale birds is still the cause of much debate, though the general consensus is that these are probably an uncommon variant of Icelandic Redpoll.
Wing length: Male 75mm – 84mm, female 72mm – 81mm.


Plate 39 - First-winter female, North-western Redpoll, presumed islandica (right bird of top & middle insert & bottom insert) with Lesser Redpoll (left bird of top & middle insert) 26th March 2011, The Knapp, Worcestershire. © Fergus Henderson


The first-winter female North-western Redpoll pictured above with a Lesser Redpoll, trapped in Worcestershire in March 2011, was presumed to be of the form islandica, predominately due to the relatively small bill structure, plus the reasonably pale and moderately dark streaked nape, lower back and rump. Note its large size, most obvious on the top photograph, compared to this Lesser Redpoll and note the ground colour to the nape, central mantle stripes, back, rump and fringes to the uppertail-coverts are a pale creamy buff, not white as seen on Mealy Redpoll. Also note that the tips to the medium coverts are distinctly buff and show an obvious contrast with the white greater covert wing-bar. The pale eye-ring is indistinct and the supercilium and ear-covert buff. The amount of black feathering around the base of the bill is extensive, while the breast and flanks are dark buff/brown throughout and broad dark streaking is present down the flanks.

Status of Mealy Redpoll in Worcestershire
Due to the complexities of Redpoll identification, it is difficult to assess the true status of Mealy Redpoll in the county, though I suspect it is an uncommon, though regular winter visitor and probably occurs almost annually. From and including the massive influx of Mealy Redpoll in the winter of 1995/96, when as many as 337 were recorded in the county, a total of 439 have occurred to the winter period 2007/08. The chart below lists the winter periods, localities and totals recorded over this period. Incredibly, between 1900-1975, just two records of single birds have been documented, in 1943 and 1944 and prior to 1995, the counties total stood at a measly 16 individuals. These figures would suggest that once Mealy Redpoll was a rare winter visitor to Worcestershire, though in reality, one would expect that it had simply been overlooked.



Breeding status of Lesser Redpoll in Worcestershire
Lesser Redpoll was reported as no more than a winter visitor to the county during the first half of the twentieth century, but by the mid 60s, small numbers were observed throughout the summer months and breeding was confirmed from a few localities with suitable nesting habitat, predominately birch woodland, thorn scrub and young conifer plantations. Totals peaked during the late 70s and early 80s, when it was considered to be a widespread, though not a common breeding species, being recorded from over 30 localities in the county. A reasonably healthy population was sustained until the mid 80s, and then numbers dwindled hereafter and reverted to the status of a winter visitor after 1990, with birds being absent from their traditional breeding grounds after May. The colonization of Lesser Redpoll in Worcestershire during the 60s correlated with the national trend and is thought to have resulted from the maturing of birch scrub that regenerated following wartime felling (Gibbons et al. 1993). The reason for its decline in the county is less understood, but again correlated with the national trend.

Recording of Mealy & Arctic Redpoll in Worcestershire
Both Mealy and Arctic Redpoll are category ‘A’ species in the county and a detailed description should be sent to the county bird recorder for assessment. In past years, the county rarities committee has unusually only accepted obviously large and pale Mealies, though observers are encouraged to submit descriptions, ideally with photographs of probable females. County ringers are also an important source of data and are encouraged to submit totals of trapped Mealies, particularly as females are easier to confirm in the hand. This will help ascertain the true status of Mealy Redpolls in the county.

Acknowledgements.
Fergus Henderson, Des Jennings, Detlef Gruber, Steve Mann, Mikael Nord, John Robinson, Brian Stretch, Peter Walkden, and Ray Wilson kindly provided the additional photographs featured in this article. Thanks to Fergus Henderson and Shaun Micklewright from the Wychavon Ringing Group for providing data on Mealy and Lesser Redpolls, trapped at Upton Warren in 2008 and to Des Jennings for suggesting alterations to the text.

References.
The Birds of the Western Palearctic, volume VIII, S Cramp, C M Perrins. Oxford University Press.
Identification Guide to European Passerines, fourth edition, L Svensson.
Moult in Birds, Ginn & Melville, BTO Guide 19.
Finches and Sparrow, Clement, Harris & Davis. Helm publication.
The New Atlas of Breeding Birds in Britain and Ireland, 1988-1991. D W Gibbons, J B Reid & R Chapman. Poyser, London.
The new Birds of the West Midland, G & J Harrison. West Midland Bird Club publication.
West Midland Bird Club, Annual Reports 1932-1996.
A Revised List of Worcestershire Birds, issued June 1961, A J Harthan.

Article written and compiled by Andy Warr. 

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