Clifford Hill Bufflehead goes west

Turning up and performing well in front of the hide at the southern end of Daventry Country Park yesterday, ‘Buffy’ was finally stripped of her celebrity status as she revealed more of that tell-tale ring detail.
Female Bufflehead, Daventry CP, 27th June 2017 (Bob Bullock). An escape from captivity with a non-conformist metal ring on the right leg.

Thanks to some excellent images from Bob Bullock, it became apparent that our Bufflehead’s ring format does not conform to any which is used in either Canada or the USA – either now or in recent history. Digits around the centre of the ring include random numbers 38, 58, 60 (or 09) and there is no alphanumeric contact detail in smaller text above or below these numbers.

Female Bufflehead, Daventry CP, 27th June 2017 (Bob Bullock). An escape from captivity with a non-conformist metal ring on the right leg showing number 58.
Female Bufflehead, Daventry CP, 27th June 2017 (Bob Bullock). An escape from captivity with a non-conformist metal ring on the right leg showing numbers 38 and possibly 09.
Female Bufflehead, Daventry CP, 27th June 2017 (Bob Bullock). An escape from captivity with a non-conformist metal ring on the right leg.

I am grateful to Chris Wood of the Cornell Lab of Ornithology, Ithaca, New York who, upon receiving copies of the above images, kindly commented as follows: “Honestly, I can’t imagine this ever being used by a researcher here. Bands have been standardized for a long time now and this just doesn’t look like anything we would use.”

Danny Bystrak, Wildlife Biologist at the Bird Banding Lab, Patuxent Wildlife Research Centre near Washington, USA, also commented: “The band looks narrow and over-sized is not something I have ever heard of anyone using in the US or Canada.” [via Chris Wood]

So, there we are. Our Bufflehead has indeed gone west … along with any chance of it being a new bird for the county.

Postscript: it is reportedly back at Clifford Hill GP today.

More on the Clifford Hill Bufflehead

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.

Female Bufflehead, ring on right leg, Clifford Hill GP, 25th June 2017, videograb.

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.

Drake Bufflehead, ring on right leg, Priory CP, Bedfordshire, 29th October 2015, videograb (Mike Alibone)
Drake Bufflehead, ring on right leg, Priory CP, Bedfordshire, 29th October 2015, videograb (Mike Alibone)

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).

Northamptonshire’s first Bufflehead?

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.

Bufflehead, Priory CP, Bedfordshire, 29th October 2015 (Mike Alibone) and examples of American rings.

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 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.


Mediterranean Gull – a new breeding species for Northants

A new species is added to the list of birds breeding in Northamptonshire as Mediterranean Gulls nest for the first time at Stanwick Gravel Pits
Mediterranean Gulls, Stanwick GP, 6th May 2017 (Bob Bullock)

Mediterranean Gulls have been appearing with increasing frequency among Black-headed Gulls breeding in the Nene Valley – particularly within the well-established Summer Leys colony. This appears to be a recent phenomenon, principally involving single birds which are apparently not sexually mature. Most remain for only a short time during spring but in 2015, a second-summer was discovered in the Summer Leys colony on 18th March, remaining there until 29th June. During this period, it established and held territory, continually displaying to the local Black-headed Gulls. This was repeated in 2016, with another second-summer visiting the colony for only a short duration on 20th-21st March. However, two adults appeared there little more than five weeks later, on 28th April, before relocating the following day to the Stanwick colony, where they were seen again on 11th-12th May. There were no subsequent sightings.

Fast forward to this year, 2017 and 5th April, when a pair was displaying among the Black-headed Gulls at Stanwick, after which they promptly disappeared. On 24th April two were again present – both wore BTO rings and one sported a black leg tag ‘SA30’, which has not yet been traced to source. Again, they were not subsequently reported but then two – amazingly a different pair – arrived in the Black-headed Gull colony on Rotary Island at Summer Leys LNR on 3rd May. Appearing settled, they remained difficult to observe in the island’s vegetation until 5th May.

The following day, 6th May, what was assumed to be the same pair appeared in Stanwick’s Black-headed Gull colony, where they were observed copulating and defending territory.

Mediterranean Gulls, Stanwick GP, 6th May 2017 (Bob Bullock)
Mediterranean Gulls, Stanwick GP, 6th May 2017 (Bob Bullock)

Nest construction ensued and eggs were laid, subsequently hatching, with the young visible within the colony. It was after this that fortune took a turn for the worse. During the first week in June the young had disappeared – assumed to have been predated by the local Lesser Black-backed Gulls – and by the end of the week both adults had also abandoned the site. Not a positive outcome for a first breeding attempt but, as this species continues to increase in the UK and indeed breeds in Cambridgeshire, we can surely look forward to further attempts in the future.

Thanks to Steve Fisher for providing information and to Bob Bullock for images.

Technology and innovation lend visibility to heronry survey

With special consent from Natural England, Assistant Warden Mischa Cross explains how specialist equipment was used with careful planning to accurately survey nesting Grey Herons at Pitsford.

In early May 2017, the heronry at Pitsford Reservoir Nature Reserve was surveyed using a drone to see if a more accurate count of nests could be established with this method, rather than counting from on the ground. The trial proved very successful with 14 nests counted from the drone footage, compared with 10 nests counted from the ground.

Aerial footage of Pitsford Water Nature Reserve Heronry using a drone, May 2017. The nests are clearly visible and can easily be counted from the photographs. Young birds can be seen on the nests.

The survey was timed so that the eggs had hatched. This meant adult birds would not be sitting on the nests incubating eggs, as they may be inclined to leave the nest, risking damage or chilling of the eggs. One flight was sufficient to get the required footage and it lasted no longer than 10 minutes. The drone used was a DJI Phantom Vision 2+ v.3, which can fly up to a maximum height of 300ft. For this survey the height was set at 200ft so better quality images could be captured in an attempt to see if egrets were also using the area. It was hoped to get video footage but unfortunately this was unavailable on the day of the survey. The drone was piloted by fully qualified, CAA approved and insured pilot, Josh Hellon. The pilot was always in full manual control of the UAV/drone and it has a failsafe that returns it to the take-off point if there are any problems.

Observations were made from the ground while the drone was in the air to see how the birds in the area reacted to the presence of the drone. No obvious signs of disturbance were witnessed. As the eggs were hatched, the adult birds are likely to have been away from the nest collecting food.

Rarity Round-up 27th May to 2nd June 2017

The calm after the storm. After some sporadic heavy rain during the first forty-eight hours, warmer weather set in as winds swung between west and south-east and temperatures edged momentarily into the high twenties. As May turned into June, the northward flow of wetland migrants enjoyed by all in the preceding weeks almost dried up and we entered a quiet period, enlivened for some at least by the brief appearance of an Arctic Skua on 2nd.

At Stanford Res the first-summer Eurasian White-fronted Goose visited again on 30th but was not alone in being the only winter visitor lingering ludicrously late at this site. A drake Garganey continued a run of intermittent appearances at Summer Leys, showing there on 28th, 1st and 2nd, while two – presumably a pair – were at Stanwick GP on 29th. The only other wildfowl during the period were Red-crested Pochards, which included a drake and a hybrid female at Pitsford Res on 27th and two drakes bouncing back and forth between Ditchford GP’s Irthlingborough Lakes & Meadows LNR and Stanwick GP between 27th and 31st.

The latter site produced another late spring Bittern, which flew on to the A45 Lay-by Pit on 29th. On 2nd June, a Honey Buzzard was reported circling above Oundle before flying south-west, a Marsh Harrier flew east at Summer Leys on 27th, while an Osprey fishing at Stanford Res on 29th-30 and again on 2nd was perhaps not entirely unexpected, given the small number of breeding pairs in the region.

Grey Plover, Stanford Res, 2nd June 2017 (Chris Hubbard)

Above average numbers of Avocets have occurred this spring and more appeared this week, with two at Stanwick GP on the evening of 28th, although they were nowhere to be seen the following day. The trickle of waders continued with two more Grey Plovers – one at Pitsford Res on 29th and the other at Stanford Res between 31st and 2nd, while a Turnstone visited Pitsford Res on 27th, followed by two more there on 31st. Hollowell Res produced the week’s only Greenshank, on 28th, while last week’s potentially record-breakingly late Jack Snipe proved officially to be just that, remaining there until at least 1st.

Turnstone, Pitsford Res, 31st May 2017 (Stuart Mundy). One of two present at this site on the same date.
Jack Snipe, Stanford Res, 31st May 2017 (Chris Hubbard)

Bird of the week, however, was the light morph adult Arctic Skua, which circled high above Daventry CP, late in the morning of 2nd, before drifting off north-west. Spring records are not unprecedented but even a stayer in autumn would be kinda nice …

After the full-on spring passage of Black Terns there was just one, at Pitsford Res, on 30th, when two Yellow-legged Gulls were at the same site. More unusual was the fly-over of two Hawfinches at Harrington AF on 29th – probably the first record for the site.

First-summer Golden Plover

On 27th May, Bob Bullock found a European Golden Plover at the western end of Earls Barton Gravel Pits, where it remained until at least 29th May, when I managed to take the photos, below. We don’t usually see this species locally beyond mid-April so any solitary ‘Golden’ Plover occurring late in the spring is worth a second look – especially when it appears as dull and greyish as this one. Remember the first-summer American Golden Plover at Summer Leys from 13th to 17th May 2001?

When seen from a distance, in overcast conditions, the initial impression might have been that of Grey Plover – especially this spring, when we’ve had larger numbers than usual passing through. However, the bill is too small and neat, lacking Grey’s length and chunkiness.

In general, this bird’s structure does not immediately match that of either American or Pacific Golden Plover, both of which are of slimmer proportions and more elegant with longer legs. Closer examination also reveals closed wings only marginally extending beyond the tail, so ruling out the much more noticeably longer-winged American, and five primary tips extending beyond tertials – the latter reaching only halfway down the tail (too short for Pacific).

The lack of summer plumage this late in the year immediately suggests this is a first-summer and a closer examination confirms this. Upperparts are rather faded, there are few ‘golden’ spangles but many off-whitish ones and the rear flanks are barred (not so in full adult) and the tail feathers are barred off-white and brown, lacking adult’s yellowish chevron-like pattern,  as well as being rather worn.

In sunlight, this bird appeared noticeably warmer-toned and, in case there was every any doubt about the identification, it gave the typical Golden Plover “puwee” call and when it flew a short distance on a couple of occasions it revealed white axillaries and underwings, instead of smoky-grey …