Tufted Duck x Lesser Scaup

Tufted Duck x Lesser Scaup hybrid, Ambleside Duckpond, West Vancouver (British Columbia, Canada), 19th March 2007 - copyright Paul Kusmin

(photo ID: 3144)

It seems pretty clear that this bird is a Tufted Duck x Scaup sp. hybrid but whether Greater or Lesser Scaup is involved is not so straightforward.  The coarseness of the vermiculations on the upperpart is different from at least some Tufted Duck x Greater Scaup hybrids and I think that is very likely to point to Lesser Scaup parentage.  In the two photos (above and below) the darkness of the upperparts looks different - that is often true in Tufted Duck x Scaup sp. hybrids, varying according to light and angle to the observer.

Tufted Duck x Lesser Scaup hybrid (same bird as in photo ID 3144 above), Ambleside Duckpond, West Vancouver (British Columbia, Canada), 16th March 2007 - copyright Paul Kusmin

(photo ID: 3145)

Tufted Duck x Lesser Scaup was the suggested ID for the following bird on the other side of the Atlantic (Tufted Ducks are vagrants among Lesser Scaup in North America while Lesser Scaups are vagrants among Tufted Ducks in Europe, so the hybrid is just as likely to occur on either continent).  The identification of this bird was discussed but I couldn't see that any clear conclusions were reached - as always, comments welcome.  There is also a video of this bird on YouTube.

possible Tufted Duck x Lesser Scaup hybrid, Møllekrogen (Denmark), 14th October 2016 - copyright Rasmus Strack

(photo ID: 3065)

Tufted Duck Aythya fuligula
Lesser Scaup Aythya affinis

Greater Scaup x Lesser Scaup

apparent Scaup hybrid, possibly Greater Scaup x Lesser Scaup, Eyebrook Reservoir (Leicestershire, UK), 10th November 2015 - copyright Andy Mackay

(photo ID: 2415)

This is a difficult bird!  I've included it under the two-Scaup heading but I'm by no means sure that is the correct ID, and acknowledge that others are leaning more towards a hybrid involving Tufted Duck (e.g. on Andrew Harrop's excellent blog), while others suspect it could be a pure Lesser Scaup.  Andy tells us that the pale subterminal band on the bill was more obvious in life than it is in the photos (more of which appear below) - and that is one good reason to consider Tufted Duck as a parent.  Many Tufted Duck x Scaup hybrids show more black on the tip of the bill, but apparently some don't, so that is not a strong enough reason to eliminate Tufted Duck from the equation.  Of more concern to me is the paleness of the back.  Typical Scaup x Tufted Duck has a much darker back lacking such coarse vermiculations as shown by this bird.  Again this does seem to be a variable feature on Tufted Duck x Scaup hybrids, however I have yet to see clear evidence that any Tufted Duck hybrid can show such a pale back as this.  A hybrid backcrossed with Scaup would be another matter, and that must remain a possibility for this bird (though a backcross to Lesser Scaup is surely beyond the bounds of reasonable possibility in the UK?).

The coarseness of the vermiculations suggest (to me at least) Lesser Scaup involvement, and indeed the bird looks a lot like a Lesser Scaup in many respects.  Andy tells me that in the field pure Lesser Scaup was never really a contender, but from the photos I think it would be a very easy conclusion to reach.  For Andy though, he saw it flap its wings twice and observed that the white bar definitely extended across the primaries as in Greater Scaup or Tufted Duck, and of course wrong for pure Lesser Scaup.

Andy also provided the following pertinent information:

"It was at least Tufted Duck size, perhaps slightly larger, and the head shape was nearer Greater Scaup, but usually with an obvious peak on the rear crown (really just a 'rough' patch of feathers interrupting the smooth curve). Also the head was strongly glossed green at all times, with just a hint of purple when seen head-on."

Worth noting that the new Helm guide to Wildfowl of Europe, Asia and North America by Sébastien Reeber has two Tufted Duck x Greater Scaup hybrids illustrated (one head only), one showing restricted black on the bill tip.  Both show a more obvious tuft than the Eyebrook bird had.  If they are the same birds illustrated in his 2002 article "Identification des fuligules et de leurs hybrides" (Ornithos 9: 177-209) then they were both darker-backed birds too.  Gillham & Gillham (Hybrid Ducks - a contribution towards an inventory, 1996) describe two male Tufted Duck x Greater Scaup hybrids as having bodies like Greater Scaup, but they suggest that these birds, which also had rounded heads and were as large as Greater Scaup) might have been backcrossed with Greater Scaup.

apparent Scaup hybrid, possibly Greater Scaup x Lesser Scaup (same bird as in photo ID 2415 above), Eyebrook Reservoir (Leicestershire, UK), 10th November 2015 - copyright Andy Mackay

(photo IDs: 2416-2418)

My first thought when I saw these photos was, "Why isn't this a Lesser Scaup?", so I was interested to receive an email from Steve Mlodinow, one of North America's leading birders and with a great deal of experience identifying hybrids, asking just that, or at least, "Besides the green on the head, why is not this a Lesser Scaup?" A green head sheen isn't enough to discount Lesser Scaup - I've personally seen green-headed birds in both UK & America, albeit eventually they showed purple under prolonged observation.  Steve went on to say,

"The head shape and bill are well within range for [Lesser Scaup], and I don't really see that bill coming out of a Greater Scaup x Tufted Duck hybrid... though I've not looked at known photos of that cross.  Ring-necked Duck x Scaup hybrids have far darker backs than this bird, and I would expect Tufted Duck x Greater Scaup to be similar."

So it seems Steve's interpretation of the photos is akin to mine.  But of course the answer to, "Why not a Lesser Scaup?" has to do with Andy's observations, rather than anything that is clearly visible in the photos.  Having said that, my own observations of both live birds and photos suggest that the wing-bar feature can be difficult to apply in poor or brief views (or imperfect photos).  Steve echoed these sentiments: "Depending on lighting, the wingstripe can be deceiving." But of course neither I nor Steve actually saw the bird, whereas Andy did, and asides from noting the possibility of error in recording wing-bar pattern in a general sense, we are in no position to question Andy's observations.  And it's worth remembering too that Andy thought the bill pattern did not look right for Lesser Scaup in life, showing too pale a subterminal mark.

Well, I shared this feedback with Andy and he's kindly supplied some more photos taken a few days earlier when the bird was more distant.  Here's what he said,

"The photos I sent might be misleading as regards the head shape, because in the field it really didn't suggest Lesser at all.  The attached three heavily cropped images were taken when I first saw the bird the week before, but much further away, and I think give a truer idea of the bird's usual head shape - much more evenly rounded and Greater Scaup-like.  I think if those were the only photos I'd got, no-one would even be mentioning Lesser as a possibility!

This is definitely the same bird, by the way - in the field I noted the occasional appearance of a slight tuft, strong green gloss to the head and that pale band behind the nail, all of which were also seen on the second occasion when it was much closer."

Well, this bird certainly does seem to be something of a mystery!  If nothing else it does provide a great example of why we should be cautious about identifying birds from photos...

apparent Scaup hybrid, possibly Greater Scaup x Lesser Scaup (same bird as in photo IDs 2415-2418 above), Eyebrook Reservoir (Leicestershire, UK), 1st November 2015 - copyright Andy Mackay

(photo IDs: 2450-2452)

Andy and I would both be interested to hear other people's views on this bird, so please let us know if you have any thoughts.



Tufted Duck Aythya fuligula
Greater Scaup Aythya marila
Lesser Scaup Aythya affinis

Ring-necked Duck x Lesser Scaup

Ring-necked Duck x Lesser Scaup hybrid, Green Valley (Avra Valley) Wastewater Treatment Ponds, Pima County (Arizona, USA), 12th February 2013 - copyright Steve Mlodinow

(photo ID: 1206)

The bill tip pattern is very unusual on this bird with the black on the nail extending up the centre of the bill slightly but not along the sides at all - best seen in the face-on shot below.  Steve also notes the dark and fairly solid (but not black) back, even pale grey sides, duskier than that of Scaup but without white "shoulder" stripe of Ring-necked Duck.  The head shape is rather like Ring-necked Duck, and the head was consistently green which is apparently unlike other hybrids of this sort that Steve had seen.  However, it lacks anything in head size, body size, or head shape to indicate that the Scaup parent was Greater rather than Lesser.  Indeed a green head colour should not be taken to infer a green-sheened parent species as a green sheen is normal for Ring-necked Duck x Tufted Duck hybrids, in which both parent species normally show a purple sheen.

Ring-necked Duck x Lesser Scaup hybrid (with Ring-necked Ducks and Lesser Scaup, same bird as in photo ID 1206 above), Green Valley (Avra Valley) Wastewater Treatment Ponds, Pima County (Arizona, USA), 12th February 2013 - copyright Steve Mlodinow

(photo IDs: 1207-1210)

For the next bird Steve draws our attention to the mostly Ring-necked Duck head shape, the pale subterminal band on bill (like Ring-necked Duck) but the reduced pale band at the base of the bill.  The back color is intermediate between Ring-necked Duck and Lesser Scaup and in his experience the back colour, head shape and bill pattern are typical of this hybrid.  The bottom photo showing the stretched wing, with a sharp contrast between the white on the secondaries and grey on the primaries, provides confirmation that the Scaup parent is indeed Lesser Scaup and not Greater Scaup.

Ring-necked Duck x Lesser Scaup hybrid (with Lesser Scaup), Kersey, Weld County (Colorado, USA), 5th April 2012 - copyright Steve Mlodinow

(photo IDs: 1293-1296)

With the next bird (a female I presume) Steve didn't see the wing bar so the Scaup parent identity isn't fully confirmed, although Lesser Scaup is presumed.  Steve says he usually picks these hybrids out by the head shape which is like that of Ring-necked Duck but just a bit subdued.

presumed Ring-necked Duck x Lesser Scaup hybrid, Capitol Lake, Olympia (Washington, USA), 23rd January 2011 - copyright Steve Mlodinow

(photo IDs: 1481-1482)

On the next bird I think there are a number of pointers towards Ring-necked Duck parent as opposed to Tufted Duck, which was also considered.  On the bill the pale subterminal band is strong and on one or two of the photos there seems to be a hint of an indistinct pale line round the base of the bill, which could only come from Ring-necked Duck if a real feature as opposed to a trick of the light.  The flanks are sullied grey which we would not expect from a Tufted Duck hybrid and critically, I think, the white at the front of the flanks extends up in a point round the shoulder much like it does on Ring-necked Duck and more than it does on Tufted Duck (or either Scaup species).  Pete tells us that the mantle appeared slightly paler than it looks in the photos, with more contrast between that and the head and breast.  Apparently Lesser Scaup was the most numerous species in the 400-strong Aythya flock in which Pete found this bird, and that seems a good bet for the grey-backed parent although it is perhaps hard to be absolutely sure Greater Scaup is not involved.

probable Ring-necked Duck x Lesser Scaup hybrid (with Lesser Scaups), Suffolk County (New York, USA), 27th January 2016 - copyright Pete Morris

(photo IDs: 2665-2668)

Ring-necked Duck Aythya collaris
Lesser Scaup Aythya affinis