Category: Wildfowl

The lady shows her ring …

… but the detail is indiscernible. I spent some more time with the Bufflehead this afternoon, hoping to see some ring detail – any ring detail – which might help shed some light on its origin. At one point, it came out of the water and stood on the bank but its visit to land was all too brief and, before I could get the scope focussed for a digiscoped shot, it was off again and back into the water. It’s also difficult to capture any decent images or video as, most of the time, it seems to be very active, constantly diving and spending 80%-90% of its time below the surface.

However, I did manage some more video, from which I took a series of grabs showing the ring, which appear below. Image A would suggest there is some inscription in the middle section of the ring, but this is far from certain. Blow-ups don’t help, either.

For comparison, here are two videograbs of the 2015 Bedfordshire bird, which was also ringed on the right leg. The proportions of the rings look similar but may not be.

They also appear to be similarly proportioned to Canadian duck rings, also illustrated below. None of this actually means, or proves, anything, of course, but it would be nice to get to the bottom of where this bird actually originated.

Persistence is required, waiting for the next time it sits out on the bank … Interestingly more Buffleheads have been seen in June than in any other month and in central England than any other area in the UK. Thanks to Andrew Cook and Mark Hill for pointing this out (source: Rare Bird Alert).

With some potentially serious negatives against it, what is ostensibly the first Bufflehead for Northants is likely to be an escape … or is it?

Late this morning, Terry O’dell discovered what later proved to be an adult female Bufflehead on the south side of the main barrage lake at Clifford Hill Gravel Pits. It was still present this afternoon, during which I managed to obtain some rather poor quality, wind-shaken, digiscoped video.

There have been two individuals deemed escapes reported recently: a yellow-ringed bird in Norfolk in April and a (presumed) metal-ringed bird in West Yorkshire last month. The Clifford Hill bird is metal-ringed on its right leg and, along with its having appeared in June, the odds are rightly stacked against it being a wild individual. Or are they?

Bedfordshire, 29th October 2015

Here are a few facts resulting from my research into the escape likelihood of the one in Bedfordshire in October 2015. I’d spent some considerable time looking at the Bedfordshire Bufflehead ring and doing some research.

I have a contact who produces a lot of video material for the BBC and I sent him some footage to see if he could freeze the ring on my video of that bird better than I could. He tried but couldn’t. The characters on the ring appeared to occupy a good 50% of the depth of the ring and appear just as a dark area. Any smaller characters above or below, if they exist, are invisible. The format could match one or two of the smaller rings in the image attached, lifted from http://www.duckbands.com/ an American site.

I also spoke to James Lees at length about it. His view from a ringing perspective was that it was more likely to have been ringed in the wild than in captivity because most collections use plastic rings, not metal, and he believes that Slimbridge is the only collection (he knows of) which uses metal rings (same format as BTO rings) for individual ID because their collection is extensive and because they move birds around to other collections to breed and keep the gene pool healthy. He also pointed out that American-ringed ducks have been seen in the UK before and that they once had a ringed Ring-necked Duck visit from the states and it ultimately found its way back across the Atlantic, and was seen again in Newfoundland after leaving Slimbridge. All this I guess we know …

So, what we have for the pro-wild camp is:

• Metal ring, indicating higher likelihood of wild than captive origin
• Ring format could match that of Nearctic-ringed bird
• 22.5 thousand Buffleheads ringed in Nearctic between 1951 & 2011
• Buffleheads can live for 18 years (OK if it’s an adult drake coming out of eclipse)
• October is the peak migration month for Bufflehead in the USA
• The bird stayed for one day only and, so far, has not been reported anywhere else
• No birds missing from local collections (but doesn’t rule out an escape from further afield)

And for the pro-escape camp:

• It had a ring of any type

That’s my analysis concluded. Read into it what you will but unless it’s seen to haul itself out on to the bank or an island, where the ring can be properly seen, we’ll never know for sure.

 

This very striking drake, found yesterday on Earls Barton GP’s Mary’s Lake by Kim Taylor, looked initially like it might be an American Wigeon x Eurasian Wigeon hybrid but it soon became clear it is actually a Chiloe Wigeon x Eurasian Wigeon.

It’s an amazing-looking bird which matches known hybrids. A potential pitfall for American Wigeon, perhaps, but green area too extensive, crown yellowish and inextensive and flanks heavily suffused grey.

But what would it look like in eclipse? Check the axillary colour: white in American, grey in Eurasian and in this individual, as Bob’s images, above, so neatly illustrate.

With most having long departed for Africa, there are probably fewer than ten Garganeys left in the UK at present. I first found this one at Ravensthorpe Reservoir on 20th September and, though not reported for a couple of weeks in late September/early October, it has a poorly marked face pattern and is readily identifiable as the same individual. It was still present yesterday. 

To my eyes, juvenile Garganeys stand out from the crowd of Teal – with which they often loosely associate – even when the face pattern can’t be seen. That combination of dark, oily-rust breast and flanks, contrasting sharp, whitish edges to the tertials and no white line along the outer edge of the under tail coverts is really quite eye-catching. The feeding habit of swimming around with the head partly submerged and rarely up-ending like Teals do is also a useful initial pointer.                                                                                                   This particular individual is clearly a juvenile based on plumage tone and the solid dark belly (female and eclipse drakes have a whitish belly) but a quick flap of the wings, revealing a greenish speculum bordered by very broad white borders, was enough to sex it as a male.

In the accompanying, rather ropey, video there also appears to be the beginnings of a male breast band – demarcated from the belly – coming through. This does not appear to be mentioned in the literature as appearing quite so early on in the autumn but I guess it has to start sometime.

As it’s been present for a month it will be interesting to see how long this bird stays around. Wintering birds are rare but not unheard of!

Billing Gravel Pits. A favourite local patch for me in my early teens when I used to cycle there regularly after school and at weekends. These days I rarely visit the main pits and the site is largely underwatched. Because of this I decided yesterday to check out the main lake, which is private, although parts of it are viewable from the road and from Billing Garden Centre car park.

Opting for neither, I parked my car at Cogenhoe Mill and walked the 1 km or so west along the river toward the main pit. After negotiating a fence and slogging through the willow herb and reeds I finally got close to the eastern end of the pit but progress was halted by a tributary of the River Nene which prevents access to the pit itself, although viewing is possible but a little distant and partly obscured by vegetation.

A largish raft of ducks was visible in the north-east corner. This consisted of tightly-packed Pochard, Tufted Ducks and a few Wigeon. A few scans through the scope initially revealed nothing, apart from a few white-faced Tufted Ducks – sadly no Scaup. Then, suddenly, an interesting head popped up among the tufties. Obvious eye-ring with short, swept-back streak, diffuse, whitish face patch around the base of the bill, rear crown peak and longish, pointed bill with black tip and a subterminal white band. Ring-necked Duck!

I watched it for a few minutes to ensure no hybrid characteristics were present. It looked good so I put the news out and continued to watch. Views were distant, partly obscured but good enough, although not up to allowing any photography. With grey cheeks, obvious long spectacle line and overall cold-toned plumage, this bird looked quite different to the Wicksteed Park Lake individual from early November, so likely to be a different bird.

Dave James was there this morning and managed to shoot this video:

For anyone going to look, the lake is private and views can be made from the road at the western end or from the car park by Billing Garden Centre.

Thought I’d post some video of the Summer Leys Garganey. Never a lame duck but not one which stands out to anything like the extent of a fine spring drake and this juvenile has a not particularly well-marked face pattern compared to many.

This is because the dark horizontal cheek bar is reduced to a blob on the ear coverts and the pale loral spot is rather diffuse. It’s a juvenile – as opposed to a female – aged by the neat, fresh feather fringes giving it an immaculate appearance, the finely-streaked neck (adult females are more blotchy here and on the upperparts), the brown, streaky belly – not visible here, but hinted at where the flanks disappear below the water level – (females have a whitish, unmarked belly) and the warm, almost rusty-brown hue to the plumage compared to the colder tones of adults.

Prompted by the last post on the subject, Minimal Interest, Joan Chaplin sent me these images of a Cackling Goose at Foxholes Fisheries, Crick from 23rd April 2012.

This bird arrived with visiting Canada Geese and was subsequently thought to be of the race minima. In common with the Daventry individual it shows a number of features which are inconsistent with that race: too large, too long-necked, the body is more elongated, the head not square enough and the bill – though small, is the wrong shape, i.e. too long.

All features are, however, spot-on for taverneri, Taverner’s Cackling Goose, right down to the thin, broken throat line which almost divides the two white cheek patches.

Note how the bird’s size and shape appear to vary with pose and camera angle! While this western USA bird was surely an escape, Taverner’s has been recorded in Ireland in the recent past.

That’s what this Cackling Goose at Daventry CP today is likely to elicit. Apparently it has been present two weeks among the local Canada Geese and, given its range along the western seaboard of North America, and its time and place of occurrence, it is almost certainly an escape – although it is a long-distance migrant!

Cackling Goose was split from Canada Goose as long ago as 2004 and four races are recognised: hutchinsii (‘Richardson’s Cackling Goose’), taverneri (‘Taverner’s Cackling Goose’), leucopareia (‘Aleutian Cackling Goose’) and minima (‘Ridgway’s Cackling Goose’). Each race is identifiable on a combination of structure and plumage characters and the individual at Daventry most closely resembles minima in plumage but it can sometimes appear a little larger than would be expected and the head shape is not quite right, minima should show a squarer head profile and shorter bill than this bird. So is it another race or a hybrid?

It’s between half and two-thirds the size of the accompanying Canada Geese, darker, shorter-necked and much smaller-billed. The main plumage difference is the all dark brown breast and belly, with the black at the base of the neck ‘fuzzing’ into it.

Richardson’s Cackling Goose is similar in size and can be almost as dark but has a clear cut neckline with normally a narrow white base dividing it from the brown breast.

Cackling Goose is not on the British List though a number of records have been accepted by BBRC. The Daventry individual is a nice bird and well worth a look, even though it must surely be an escape …

It has been less than a year since I summarised the Northamptonshire status of Ruddy Shelduck and speculated on the possible origins of birds visiting the county. There is an annual pattern of late summer/early autumn occurrences which ties in nicely with the now well established post-breeding, summer moult migration to The Netherlands. It would appear that birds occur locally as a result of dispersal from The Netherlands after they have completed their full body moult, which leaves them flightless for about four weeks.

There are currently two – a male and female – at the southern end of Pitsford Reservoir, which were first discovered on 24th June – a somewhat earlier arrival date than would normally have been expected.

Ruddy Shelducks, Pitsford Res, 30th June 2014 (Mike Alibone)

The date coincides with the arrival of others in the UK: two in Gloucestershire on 19th and singles in Staffordshire on 25th and Cheshire on 28th, while the build-up in The Netherlands has also begun with two hundred or so at Vreugderijkerwaard, west of Zwolle (remember the Hawk Owl? 🙂 ) on 27 June. A flock of ten had also reached the west coast island of Texel by 25th June where, according to René Pop, they are very unusual; from here it is just a short hop to East Anglia …

The Pitsford birds are in active moult and the drake at least is flightless, having shed all its primaries and secondaries. This, then, begs the question, are we now getting some of the ‘Dutch’ birds before they moult?

The origin of the ‘Dutch’ birds is still not fully resolved but we are now more than half-way to understanding where they come from. In an attempt to discover the source of the summer moulting population a Ruddy Shelduck Work Study Group was set up and, in 2013, it launched an investigation into the origin of the large numbers (eight hundred or so) summering at the Eemmeer as well as those elsewhere in The Netherlands. Forty-eight were trapped and fitted with individually numbered yellow neck-collars and seven were fitted with GPS transmitters.

As a result of this we now know that many – if not all – of these birds are from feral populations in Germany  and Switzerland, and it has been established that birds from the German lower Rhine and the Swiss birds are connected to each other. However, there are still a number of individuals with collars which have not been seen after having left the Eemmeer in August 2013. The Dutch are still hoping that these may be from the ‘wild’ population in south-east Europe. It’s nice to dream …

Back to the feral birds. The German and Swiss populations are said to be growing, particularly around Lake Constance, at the tri-point of Switzerland, Germany and Austria, where approximately six hundred and forty were counted in February 2014. There is some concern in the region that they may successfully compete with other hole-nesting species and this has conservation implications. For this reason, along with the fact that this is a European ‘C’ list species and, therefore, potentially worthy of admission to the British list, shouldn’t we be taking Ruddy Shelducks a Tad more seriously?

The Marbled Duck, first discovered by Steve Fisher at Stanwick GP’s main lake on 13th January and still present today, promptly disappeared almost immediately until rediscovery on 19th February. Or did it? With persistent inclement weather, rising water levels and less than ideal viewing conditions, it appears it may have been there, somewhere, all the time as it is now known to hide among the overgrown islands on the western side of the lake.

Despite being recorded sporadically in the UK, this species remains on category D of the British List as it is common in captivity but an established pattern of records suggests it is likely that some wild individuals occur.  Vagrants have been recorded in Northern Spain and in the Camargue in Southern France with most French records in August-September and a secondary spring peak in April. The pattern of British records also reflects this and Marbled Duck has been accepted as a genuine vagrant in the Netherlands.

Pouring at least some cold water on the vagrancy hypothesis, analysis of the stable-hydrogen isotope content of feathers taken from a first-winter shot in Essex on 1st September 2007 suggested that the bird originated from outside of the normal breeding range of the species and was most likely to have been of captive origin (see British Birds).

Although thought to be in decline, the global population is estimated at c.50,000-55,000 individuals, based on estimates of 3,000-5,000 in the west Mediterranean and West Africa, 1,000 in the east Mediterranean 5,000 in south Asia, and at least 44,000 individuals counted in Iraq in 2010 according to BirdLife International.

There has been one previous record of Marbled Duck in the county – coincidentally at Stanwick GP, on 29th June to 3rd July 1990.