Category Archives: d) Diving Ducks

grupo IMG_1189

A nice flock of White-winged Scoters

by Guillermo Rodríguez

Although White-winged Scoter is very common in winter along the east coast of the US and Canada, they are rarely found close enough to shore to see plumage details, or at least rarely in large numbers. In late November 2016, a huge flock of this species built up off Crane Beach, Massachusetts. The 700+ birds were feeding on an unidentified species of mollusk for a period of roughly one week, very close to shore (at least by scoter standards). The Crane Beach flock provided an exceptional opportunity to study a large number of individuals, which I couldn’t let pass. Despite the freezing ocean breeze on a very windy day, I managed to take a good number of pictures that show the variability of some key characters well.

Below I present a small sample of my pictures from that day, with the goal of revisiting and testing some of the identification and ageing criteria (presented in eg Garner et al. (2004), Reeber (2016)).

WARNING! This post contains many pictures!

All photos were taken on November 23rd, 2016, in Massachusetts. Note that due to the warm light of the sunrise most birds look very brown-tinged, but they usually look much darker in the overcast light conditions that are typical of NW Europe.

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The mollusk they were feeding on – Eastern Slippery Shell?

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White-winged Scoter: a juvenile male (right at the center) with three adult females and three adult males.

Adult males (including second-years)

Here are some pictures of adult males showing the variability of the bill pattern, the white tick mark at the eye, and the extension of brown on the flanks. As is well known, the characteristic head shape and the bill pattern allow a straightforward separation from both Stejneger’s and Velvet Scoters.

male hint of horn IMG_0637

White-winged Scoter, adult male.

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White-winged Scoter, adult male. Note the particular shape of the flank feathers.

This male (below) presents a “hint of horn”, not very different from that shown by some Stejneger’s (see, for comparison, the Stejneger’s seen in December in Alicante, Spain), and a quite equilateral nostril. The “two-stepped” head profile, lacking the oval, eider-like shape of Stejneger’s, is still very obvious.

comparacion_stejnegeri_lowres

White-winged Scoter (left) and the recent Stejneger’s Scoter (right) from Alicante, Spain. The Stejneger’s picture © Jana Marco, one of the finders of this mega!

Some second winter individuals completely lack the white mark behind the eye, whereas in others it’s present but is still shorter than in older birds. Head and bill shape, including the markedly two-stepped profile, is usually not fully developed at this age and some still show a relatively flat head profile. Bill tip is uniformly pink, with thicker black margins than in adults. Lack of the tricolored bill pattern of adults is also typical of a young age. Some of these young adult males seem to lack the brownish feathers on the flanks, and look more uniformly black than adults.

second winter IMG_1047

White-winged Scoter, second year male, lacking white tick mark.

second winter vuelo IMG_0655

White-winged Scoter, second year male, with limited eye tick mark.

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White-winged Scoter, “young” adult male (presumed 2w), showing typical immature features such as greyish iris and pink bill, lacking any yellowish or orangeish tones.

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White-winged Scoter, adult male (left) and a male showing some immature traits (right), eg short eye tick mark, pink bill and not fully developed bill knob.

[Ageing female-type birds]
Ageing of female-plumaged birds is often simple, as many adult females are completely dark and even jet black. Differences in the head shape, the shape of the wing coverts (which are uniformly fresh and rounded in juveniles, and more squared in adults) and the paler belly in juveniles are also supportive. However, the most important feature for me is probably the pattern of the GCs and, in particular, the presence of white tips. The pattern is usually difficult/impossible to see when the birds are on the water, so it usually requires pictures in flight:
adult females: completely dark inner GCs, but the white tip sharply increases in size in the meadial GCs and can occupy almost the entire feather
first-year males: usually a small spot at the feather tip, of uniform size in all the Gcs or at most a gradual and slight increase, but always occupying <50% of the feather
first-year females: very small or completely absent white spot in all GCs

adult female vuelo IMG_0648

White-winged Scoter, adult female: note largely white medial GCs, bright reddish feet, squared wing coverts, very broad primaries.

female oscura vuelo IMG_8805

White-winged Scoter, adult female.

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White-winged Scoter, first winter male: limited amount of white in the GCs

first year male vuelo IMG_0665

White-winged Scoter, first winter male.

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White-winged Scoter, first winter female.

I guess ageing criteria are the same for Velvet, but I never had the chance to look into the subject in detail in Europe (Velvet is regular but scarce in Spain). I usually find it problematic to understand the pattern and variability of s1, which is sometimes described as the key feature to age these scoters, so I won’t make further comments on this feature.

Adult females

Adult females vary from very dark birds (looking like a “dirty” version of adult males) to those having the more classic brown plumage with two pale areas on the face. I think that the first type is actually much more common than the latter; the number of these overall black birds within the population appears to be only slightly lower than the number of adult males eg from a sample of 205 birds, 14.6% were adult males and 12.2% were these black presumed females. I wonder if there is an age-related variability, and the black birds are actually the older females.

female oscura del todo IMG_1267

White-winged Scoter, adult female.

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White-winged Scoter, adult female: note the squarish shape of the wing coverts.

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White-winged Scoter, adult female.

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White-winged Scoter, female: dark below, slight bill bump, apparent bright feet, not very uniform back feathers… not sure about the age, could this bird be an adult?

The black-plumaged individuals are sometimes identified as first-year males with an extensive first pre-formative moult, but I think this explanation can be safely ruled out based on the GCs pattern (see the shots in flight above), the bright color of the feet, the dark irises, and the squared wing coverts shown by most of these birds. Only when the formative moult is much more advanced, around late January/February, first-winter males look similar, although with a much dirtier plumage, often looking “patchy” and not as uniformly jet black.

adult females with first year juv deglandi first winter male IMG_0199

White-winged Scoter, two adult females with a first-year male (right).

The head shape of these birds actually recalls that of adult males, due to a squarish head with a flat crown, a straight (non-concave) forehead profile and the hint of a bump at the bill base, leading to a two-stepped head profile, although it is much smoother than in males. Although the differences are sometimes subtle, I think these features are distinctive enough to allow separation from Velvet in most cases. Take a look at this compilation to get a sense of the variability in head and bill shape in adult females:

adult_female_lowq

White-winged Scoter, adult females: variability in head and bill shape.

Note that some adult females present some diffuse pink “brush-strokes” at the bill tip, but the iris seems to be pretty dark in all the individuals (cf first winter males, see below).

First-year males

By late November, juveniles still look very fresh, and the pale velvet at the base of the bill often looks nicely neat. Around 40-50% show what seem to be signs of moult around the face, and a few males have already developed a pale greyish iris and pink in the bill. But even birds that still have a completely juvenile appearance can be readily sexed by the elongated bill and very flat head profile, in contrast to females, which show a shorter bill and often a slightly angular (concave) head profile.

comparison juvs IMG_1226

White-winged Scoters, first-year male (left) and first winter female (right). In my opinion, many juveniles can be reliably sexed in the field on grounds of the head and bill shape. Note, on the back, another first year female (left) and first year male (right).

no todos IMG_1118

White winged Scoter, first year birds. Sexing is definitely not always possible – this bird (center) looks intermediate, or perhaps on the female side?

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White-winged Scoter, first-year male: a nice bird still in completely juvenile plumage.

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White-winged Scoter, first-year male: gradual lightening of the iris, traces of moult around the face.

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White-winged Scoter, first-year male. This looks like a VERY advanced first year male.

Regarding the separation from Velvet, in addition to the head shape, the shape of the feathering at the base of the bill is quite distinctive given sufficiently close views; it extends further onto the bill than in Velvet and forms a 90-degree angle in the lower corner, always below the position of the nostril. A few more examples of (presumed) first-year males:

first_winter_male

White-winged Scoter, first-year males: variation in head and bill shape.

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White-winged Scoter, first-year male. Interesting individual with a narrow bill, and relatively rounded shape of the feathering at the lower corner of the bill base.

First-year females

Undoubtedly the most problematic group, many first-year females look very similar overall to Velvet Scoter. With short bills, and often concave and rounded head profiles, it may be extremely difficult to pick one out among a flock of Velvets. However, the shape of the feathering at the base of the bill, even if it is not as distinctive as it is in males, is still quite a good character when properly seen. Most birds (>60-70% ?) clearly show, below the nostril, a right angle:

first year pico ejemplo IMG_1247

White-winged Scoter, first-year female.

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White-winged Scoter, first-year female.

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White-winged Scoter, first-year females. In a few juveniles, the pale spots merge, giving a striking appearance.

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White-winged Scoter, first-year female – convex and rounded head profile, similar to Velvet.

first_winter_female_lowres2

White-winged Scoter, first-year female: variation in head and bill shape.

In a few birds the angle is not as sharply defined, looking rounder and closer to the nostril, and the pattern is probably consistent with Velvet. But this seems to be the exception and not the norm!

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White-winged Scoter, first-year female, showing a rounded corner of the feathering at the bill base.

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White-winged Scoter, presumed first-year female.

Black Scoter and Common Scoter ID

and check out  the eye-ring!

Christian Wegst kindly sent his paper though earlier this spring and its taken me ages to put it up. Given the winter cometh and wildfowl watching will go up- it’s not bad timing, even though I feel I owe Christian an apology. A great resource and could inspire some getting out and looking 🙂

Meanwhile chatting with top N. American birder Ned Brinkley, he has righly emphaised that the coloured eye-ring is VERY different between the two taxa. ID should be simples then!

Read the paper by clicking HERE:

 

Separation of Black Scoter from Common Scoter

 

The Orbital Ring

Hi Martin – I’ve received a manuscript from some California birders on the first North American record of Common Scoter, and they note that the bird’s eye-ring was bright yellowish orange, typical of Common Scoter, whereas Black Scoter tends to have a duller or dusky eye-ring. I don’t have a copy of your Frontiers book as yet. In a search of images of breeding adult males of each online, I’m seeing about 95% of adult male Common with vivid/distinct yellowish eye rings, whereas Blacks appear to have no detectable eye-ring (or in a few cases, a very thin dull yellowish eye-ring). What do you think of this? A Google and Flickr search of images took me just five minutes, but the contrast between these taxa in this respect was surprising.

Ned Brinkley

Hi Ned- I get nil points for speed. Sorry for being so slow. This sounds a great record in California. The text in ‘Frontiers’ in Birding’ refers to americana and says ! ‘Eye-ring tends to be bluish-grey not yellow’  in nutshell yellow eye-ring for Common Scoter – nigra, blue-grey for Black Scoter- americana’. My stuff is about 15-20 years old and may well need sharpening- sounds like your observations are doing just that. So we agree though your precise details are probably more accurate.  

Martin

Common and Black Scoters (1 of 1)

Separation of Black Scoter from Common Scoter

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ANSWERS. To Eider Prize Quiz

Not so easy 😉

Thanks to everyone who had a go at the female Eider prize quiz. Not easy!

Six people named all 4 birds correctly to their taxon/ subspecies level. Well done- they were:

Kent Olsen, Davy Bosman, Liger Alexandre, Mike Buckland, Tony Davison and Hans Martin Høiby. (if I missed anyone- tell me quick!)

and drawn from the hat (by Abi Garner) the winner is drrrrrrrrrrrrr is :

Mike Buckland

I was heartened that by using new features and what for me is ‘right-now’ learning, these and other female Eider can often be identified to a subspecies/ lowest taxonomic unit level- especially when location and circumstance are taken into account. There’s’ more in the new book of course!

A copy of the Challenge Series: WINTER is on its way to Mike.

 

female Eider 1 (below) is a female Northern Eider – borealis

female Eider one (1 of 1)

Above. Female Northern Eider, borealis, Sindri Skúlason. Quite a few plumped for faeroeeensis on this one. Many true Faeroes birds are a deep peaty brown colour- e.g. lovely photo by Silas Olofson in new book.

 

female Eider 2 (below) is a female Dresser’s Eider dresseri

female Eider

Above. Female Dresser’s Eider, dresseri, by Chris Wood.

 

female Eider 3 (below) is a female Pacific Eider –  v-nigrum

Eider female

Above. female Pacific Eider v-nigrum, Chris Wood

female Eider 4 (below) is a female nominate (Common) Eider- mollissima

female Eider three (1 of 1)

Above. female (Common) Eider  – nominate mollissima by Martin Garner.

Fanad, co Donegal

Where much borealis discovery and learning happened for me. This pair while late on (June) and the male is a little worn and just beginning moult to eclipse- you can see nostril position looks pretty good for borealis on both- togther with other features. More on this in Challenge series: WINTER.

 

Eiders MG (1 of 1)

 

Black Scoter in Poland

First winter male

Zbigniew Kajzer

Hi Martin,

What do you think about this Scoter? I found it yesterday (18th March 2015) at Dziwnów, west part of Polish Baltic coast. I think it is a  2cy male Black Scoter Melanitta americana. I’m very curious about your opinion.

Previously I found two males of Black Scoter (in 2009 and 2013) but both were adults. We have 5 accepted records in Poland so this immature male represents 6th record. Here is gallery of Polish records of Black Scoter. 

We have on west part of Polish Baltic coast to 6% of the wintering Baltic population of Common Scoter. The number of Common Scoter is highest in spring (March-April) to more than 25 thousands.

Best regards, Zbigniew Kajzer

 

YES!  It’s a corker isn’t it? (I think Zbigniew knows very well how well he has done- 3 records!). I am not sure but Black Scoter in ‘first winter’/ 2cy male plumage remains extremely rare in the Western Palearctic with perhaps only one/two other claims in the UK? Profile photos like these provide the best angle for ascertaining the position and extent of the yellow bill ‘lump’ which here is out-with any appearance of odd/variant Common Scoter and spot-on for Black. It’s a belter!

2cy Black Scoter poland

The 3rd Pacific Eider for the Atlantic

V-nigrum strikes again!

Alvan Buckley*

“Hi Martin,

Today (8th March 2015)  Ed Hayden and I found a v-nigrum Common Eider on the southern shore of the Avalon peninsula of Newfoundland.

The black “V” under the chin was very strong and easily detected despite ~200m distance. It was seen when the bird was choking down a mussel of some sort.

As you know, this would be the second record for our province – and only the third (??) record for the Atlantic ocean. I have written on my blog HERE.

Exact location was off St. Shott’s, Newfoundland, Canada.

Thanks! Alvan”

* Alvan has previously found among other tackle, little gems like Kamchatka Gull (BOOM!) on his Newfoundland patch and more discrete European, schinzii type Dunlin. See Alvan’s blog >>>HERE<<<

“This one ticks all the boxes for V nigrum. The downsloping head shape- deep curvature of the black cap with green extending under horizontally, black chin V, shape of lobes spot-on— fantastic! Now to refind that one in Varanger at GULLFEST 2015…”

v nigrum7 (1 of 1)

v nigrum8 (1 of 1)v nigrum9 (1 of 1)-2v nigrum4 (1 of 1)v nigrum5 (1 of 1)v nigrum9 (1 of 1)-2

 

Northern Eiders off NE Canada

nostrils and carrots

Martin Garner and Bruce Mactavish

The Challenge of finding and identifying Northern Eiders ssp borealis as grabbed my (MG’s)  attention since around 1982! A water shed in the the 1990’s came with the find of a flock of 7 credible Northern Eiders off Fanad Head, co Donegal, with among Surf Scoter and a probable dresseri/ borealis intergrade. The same site eventually hosted the first Dresser’s Eider for the Western  Palearctic. Searching for sailed Eiders took off! NE Scotland became a boiling pot of Eiders, sails and lively discussion. Que this more recent paper:

Hellquist, A. 2014. Identification of Northern Eider. Dutch Birding 36: 221-231.

One of the author’s observations is that nostril postion can be discriminatory in identifying borealis from nominate mollissima. Simply put (and read the paper for the proper version!) you want a nostril position that is pretty much BEYOND the end of the feathering rather than heavily overlapping with it.

Start here to see what is meant with this nominate mollissima Eider in Varanger. The nostril overlaps with the end of feathering.

Common Eider nominate mollissima, Varanger Martin Garner

Common Eider nominate mollissima, Varanger Martin Garner

Common Eider nominate mollissima, Varanger Martin Garner

Common Eider nominate mollissima, Varanger Martin Garner

NE Canada

OK? Now I have always felt whenever delving into the subject that the Eiders of North East Canada were the most stand out- THIS is borealis baby land!  I have a high degree of Bruce Mactavish homeland envy and he has recently got some fantastic images showcasing the Canadian borealis.

Check out the nostril position on these shots by Bruce off Newfoundland last month:

Northern Eider ssp. borealis, Newfoundland, Feb 2015, Bruce Mactavish

Northern Eider ssp. borealis, Newfoundland, Feb 2015, Bruce Mactavish

Northern Eiders ssp. borealis, Newfoundland, Feb 2015. Bruce MacTavish

Northern Eiders ssp. borealis, Newfoundland, Feb 2015. Bruce MacTavish

Fanad, Co Donegal

Now have a look at this one taken of Fanad by Brett Richard’s. This bird was with the Dresser’s Eider.

Northern Eider, ssp borealis, Fanad, Donegal, Brett Richards. June2011.

Northern Eider, ssp borealis, Fanad, Donegal, Brett Richards. June2011.

NE Scotland

I trawled though quite a lot of shots of ‘sailed Eiders’ from NE Scotland. There might be some but I could find NONE with pro-borealis nostril position. Nada.

But this one- in Northumberland fits (if a little swollen)…

Apparent Northern Eider  ssp. borealis, Northumberland, May 2008 Tim Dean. The nostril position is very favourable!

Apparent Northern Eider ssp. borealis, Northumberland, May 2008 Tim Dean. The nostril position is very favourable!

Not all

This borealis (on range) on Svalbard would not be identifiable out-of-range.

Northern Eider ssp borealis, Svalbard, Chrys Mellow. This one has nostril no different to nominate mollissima

Northern Eider ssp borealis, Svalbard, Chrys Mellor. This one has nostril no different to nominate mollissima

and finally back to Bruce Mactavish in Newfoundland with grateful thanks…

He has a fantastic rich Eider vein to mine. V-nigrum, possibly v-nigrum intergrades, pucka borealis, Harlequins and as below Dresser’s Eider on the left with the King on the right.

Dresser's Eider- adult male in top left, with Northern Eiders ssp. borealis, Newfoundland, Feb 2015. Bruce MacTavish

Dresser’s Eider- adult male in top left, with Northern Eiders ssp. borealis, Newfoundland, Feb 2015. Bruce MacTavish

and this carrot bill still has me head scratching…

Carrotbill-x

 

 

Carrot-billed Eider off Newfoundland

Yesterday

Newfoundland’s Bruce Mcatavish emailed a rushed set of news and photos- check out this bad boy! See Bruce’s post HERE.

Carrotbill-x

A remarkabley bright orange-billed drake Eider. Thoughts instantly turn to the possibility of it being Newfoundland’s second record of Pacific Eider v-nigrum. Is that what it is?

Hmmm

We don’t think this is a  v-nigrum. At first glance it’s inspired but appears to completely lack a bunch of key characters.

Specifically v-nigrum should have deep curvature to base f black cap- horizontal on this bird with forehead bump- very typical of borealis. There is not enough green under black cap (under there seems tad more than most of borealis around it). I don’t think the basal lobes feathering intruding into bill base are big and fat enough. The bare skin frontal process should be short-looking for v nigrum

So what is it?

Either an extreme coloured borealis (not impossible) or that all-in v-nigrum from a few years back got cheeky with the locals?

IMG_1455-yup

 Palmer’s words.

The Handbook of North American Birds:

Referring to the Davis Straights/W &SW Greenland and southerly East coast… between Greenland and Canada...both typical and atypical v-nigra have been taken (not breeding) including measurements in Schioler (1926). Schioler indicated they occur there every winter…

J.C .Phillips (1926) thought them merely individual variants (of borealis) and not true Pacific Eiders.

So… the answer is?