22 November 2014

Portuguese-ringed Lesser Scaup in Wales

Here Mark Waldron relates a quite exceptional resighting at Llangorse Lake in south Wales:

"On 17th October, scanning through a flock of 100 or so Tufted Duck that were feeding just off Llangasty car park, I came across a duck which had a bright orange or red nasal saddle. At first I was so concerned with reading the saddle that I hadn't taken much notice of what the duck actually was. It suddenly dawned on me that I was not watching a Tufted Duck but a Scaup. This made it even more exciting as I desperately struggled with the code. I digi-scoped a number of photo's hoping that I may be able to read the code from the photos later if needs be. The Scaup came much closer to the reed bed, perhaps only 2-3 meters away from its edge and with a brief break in the cloud giving better light I clearly saw the code read 'YH'.

However, the better light also clearly showed light grey vermiculations along its flanks. Alarm bells started ringing in my head; could this actually be a Lesser Scaup? It was similar in size to the surrounding Tufted Ducks and I checked the head carefully and there was the bump at the back. I now started taking photo's trying to get a decent profile shot. It continued to feed and occasionally preen so I made a film of the bird during which it gave a brief wing flap. I knew I needed the wing pattern and I hadn't managed to clearly see it. I now set my camera up on a repeat shot mode to try and capture the wing pattern. Another wing flap eventually came and I got some shots, but the wing bar looked too pale in the primary feathers. I had to leave the lake as I had to attend an open afternoon at my daughter's school, but all afternoon my mind was going over the ID features and I was still leaning toward Lesser Scaup.

A search of the colour-ring website did not turn up any clues as to the source of the ringing project: this actually increased my hopes. Following further feedback the next day and comments from Andrew King, the county recorder, following his own observations of the bird I was convinced we had identified a Lesser Scaup. The real clincher came on Sunday when Andrew found a blog post that showed what looked like a first-winter Lesser Scaup that had been ringed in Portugal at São Jacinto Dunes Nature Reserve (over 1500km from Llangorse Lake). More than that, the photo's appeared to actually show 'our bird'. Later that night, confirmation was received from David Rodrigues that our Lesser Scaup had been marked at São Jacinto as a juvenile male juvenile Lesser Scaup on 20th December 2013. It was also confirmed that the nasal saddle code actually read 'VH' and not 'YH' as previously reported. The bird then remained at São Jacinto until 3rd February 2014."

This is, unsurprisingly, our first recovery of a Lesser Scaup, and as far as we can tell the first ever European recovery. Such records of transatlantic vagrants aren't exceptional, and there is even a record of a bird 'going back': a Ring-necked Duck ringed in Gloucestershire in March 1977, shot in Greenland in May later that same year. Rather coincidentally, the only other Ring-necked Duck recovery involving the UK also involved Llangorse Lake, with a bird ringed in Canada in September 1967 shot there in December that year.

Thanks to Mark and David Rodrigues for the photos of this bird either end of its journey.

13 November 2014

Winter of the Wisp

During the winter, our population of Snipe increases with an influx of birds from the continent and in some years this could be as many as a million birds. The reports of Snipe into our Ringing Scheme mainly come from hunters reporting them shot (90%+).

Summer Snipe in Iceland - Nigel Clark

We recently heard of one of these birds being 'found' this way in County Monaghan, Republic of Ireland. This bird was ringed on 1 August 2013 as a juvenile bird at Turov, Zhitkovichi district, Belarus and made the 2,302 km movement to Ireland. This is the fourth Belarusian-ringed Snipe to be found in the UK or Ireland; the majority of foreign birds come from Germany, Sweden, The Netherlands, Iceland and Denmark.

Ring recoveries show Snipe that breed in the north of the UK move to Ireland for the winter and Snipe that breed in the south of the UK move to France or Spain, with a few moving to the near continent. This draws on some parallels with Blackcap that we have reported previously, where birds come to the UK and Ireland for the winter while some or all of our UK and Ireland population go south.

So far this year the winter has been unseasonably warm, so we haven't experienced large movements of Snipe yet but in the next few weeks it is forecast that as the temperature will drop in Russia and central Europe, and so water bodies freeze over, more Snipe should reach these shores. If the temperature doesn't drop, the reporting rate via BirdTrack might continue to decrease.

04 November 2014

Ringer migration confirmed by a Blackcap

Back in September, we posted about the large numbers of Blackcaps that were moving through the central and western parts of the country. We were contacted recently with a fantastic story of a chance re-encounter between a member of the Brewood Ringing Group and one of these migrants.

Colin McShane writes:

Over the last 8 years I have been leading an Autumn ringing trip to the Parque Ambientale, in Vilamoura, Portugal with support from Vitor Encarnacao who heads up the Portuguese Ringing Scheme. Our trips have been successful on several levels and many British ringers have joined us over the years to expand their experience.

We have also controlled a number of birds from northern Europe, including Reed Warblers from Belgium, France, Germany and Sweden, and Bluethroats from France. On 06 October 2014 during this year’s trip, I extracted a male Blackcap from one of our standard mist nets and was very pleased, although not too surprised, to find that it was carrying a BTO ring. Back at the processing station, Dave Clifton (who has been an ever-present fixture on these trips) was doing his stint as the scribe. Having announced to the group what I had extracted, I began to process the bird - first reading out the ring number several times for accuracy.

Dave went quiet. He quickly got onto the phone to his wife, who checked in his ringing book back home. Hey Presto!! The bird was indeed one (of only two Blackcaps ringed at the site) he had ringed at Duckley Plantation, on the north shore of Blithfield Reservoir, Staffordshire on 11th September 2014 - only a few weeks before we had left for Portugal!!

Unfortunately Dave wasn’t able to buy a Lottery ticket on that day, but it must be a given that he was pretty certain of a big win with that kind of luck. We are looking forward to next year’s trip where we are certain that we will catch one of the many Red Spotted Bluethroats that we have been ringing in the Varanger region of northernmost Norway - no problem.....?

Thanks to Scott Petrek for letting us know - Eds

28 October 2014

Bumper Barn Owl breeding season

Barn Owls are one of our most iconic and recognisable birds. Over the past couple of years this species has struggled due to severe weather events, with last year being particularly difficult as reported here and here. It is estimated by Colin Shawyer of the Barn Owl Conservation Network (BOCN) that only one third of the British Barn Owl population attempted to breed in 2013.

Successful Barn Owl breeding seasons are dependent both on favourable weather conditions and food availability. The primary food item for Barn Owls is the Field Vole which demonstrates cyclical population trends. Reports coming in to us here at the BTO suggest that 2014 is a good vole year and as a result, may turn out to be the best Barn Owl breeding season since 2007. Early estimates from the BOCN suggest that an average of 33% of pairs have had second broods this year, although in some areas, this figure could be as high as 65%. Average brood size (first and second broods) is also high although the recent spell of wet and colder weather may have impacted on fledging success for some broods.

Whilst we have not yet had all of the ringing data for 2014, the totals are already up on last year. For example, in 2013, only 20 Barn Owls were ringed in May and 183 were ringed in June. This year to date, we have received the details of 428 Barn Owls ringed in May and 1,814 ringed in June!

Adult Barn Owl (photograph by Ruth Walker)

The following stories have been sent to us by some of our Barn Owl ringers and nest recorders:

Chris Griffiths of the Montgomeryshire Barn Owl Groups writes:

Our record year was in 2005 when we had 73 pairs producing 249 pulli. Following the two hard winters of 2010 and 2011, then deep snow in March 2013, we slumped last year to 14 breeding pairs producing 49 pulli. This year Montgomeryshire had 37 pairs producing 149 pulli. Interestingly a third of this year’s birds have been recorded at “new sites”, either newly erected boxes, or boxes that have been up a while but have never been used. Many of the “traditional” sites remain empty. For the first time since I have been involved with MBOG, thanks to ringing, I can confirm that we have also had a few second broods this year.

One unusual instance this season was that I found a ringed female bird in a box with four young on 12/6/14. This female was ringed by me in 2013 and counting back she must have started breeding at eight months of age.  On 21/7/14 I found her again 4.4 km away on a second brood of six eggs and one freshly hatched chick. A quick chat with Colin Shawyer revealed she must have left her first brood nine days after I had ringed that clutch. Apparently, this is not unusual but the distance of 4.4 km is! She almost certainly took up with another male, probably on the edge of his “territory” and left the first male to bring up the kids alone (this is something BOCN were beginning to suspect at a number of sites in years where double brooding occurs).  The good news is that the first brood of four and the second brood (which had dwindled to five when I ringed them) all fledged successfully. On returning to the first site at the end of August, we found “superdad” (who was caught and ringed in a nearby box earlier in the season) in the box with another male that I had ringed as a pulli last year 11 km away.

Barn Owl chick (photograph by Ruth Walker)

Alan Ball writes:

Barn Owls have done exceptionally well in Lincolnshire this year. Bob Sheppard and I have monitored nearly 400 nesting attempts from at least 340 pairs and have ringed over 1,200 chicks. We have not rechecked every site, so will have missed many second broods as probably around a third will have attempted to breed again. Now, in mid-October, some of the late second broods are struggling as weather and food availability has an effect, but we are still finding a few healthy broods. Of particular note this year was one fen just south of Bourne, which had six pairs, raising four broods of seven and two of five. It's amazing that one fen of approximately eight square kilometres could furnish enough food for 12 adults and 38 young. Prey encountered in nest-boxes suggests that there has been an abundance of field mice as well as voles this year.

As well as Barn Owls, other species have taken advantage of the abundance of prey and Bob and I have also ringed 449 Kestrel chicks out of 150 pairs monitored, 188 Little Owl chicks from 80 pairs and 120 Tawny Owl chicks. I am now part-way through the daunting task of completing all the Nest Record Cards to record the 2,500 birds of prey handled this year.

Peter Wilkinson sent us this wonderful photograph (taken by Chris Chatfield) of five Barn Owl chicks sitting on their box. 

Geoff & Jean Sheppard, who carry out a RAS project on Barn Owls, write:

Our study area is in the SW corner of Scotland where we monitor about 80 sites, the majority of which have a nest box. Although there was not a large increase in occupied sites, few had single birds and most were successful with notably larger brood sizes. The number of pulli ringed almost doubled but the number is still well below the usual 150+ achieved in the previous decade. For the first time in many years, a pair at one site had two broods, a six and a four. Interestingly, in certain areas, many sites remained unoccupied suggesting that vole numbers had not increased uniformly and this may be due to the fragmented habitat in the study area. This year, in three occupied sites the pulli failed to survive due to death of one or both adults. In one case, this was due to Jackdaws completely blocking the nest box entrance and trapping the female with her chicks at the back. On a lighter note, a pair in a derelict cottage forsook their usual loft space and raised their brood on the corner of an old bunk bed!

Colin Shawyer writes:

Perhaps my most well studied Species Recovery Areas is that in the Peterborough District. This work was initiated in the early 1990s and, as a result of concerted conservation effort, has seen an increase in the breeding population from six breeding pairs in 1992 to 60 pairs today. The 80 artificial nest sites which have been installed here, largely on a 1.5 km grid matrix, have been monitored annually during the last 20 years and the study area now represents the highest density of breeding barn owls in the UK. This year has seen 75 of the potential sites available in the study area, occupied by 60 breeding pairs with about 70% of these double brooding. The average first brood size (close to fledging) this year is slightly greater than four with ringed broods of six, seven and occasionally eight at about 50% of sites. Second broods are still being ringed but as is normally the case, although clutch sizes are generally higher than in firsts, brood depletion is almost always greater with some having gone from seven chicks to fledge one, two and three. The average second brood size at ringing is, nevertheless likely to remain above three. At a few sites, fledging success over both broods has exceeded ten!

16 October 2014

Tay Bearded Tits on the move: can you help?

In the UK, the largest single population of Bearded Tits, also sometimes known as Bearded Reedlings, occupy the Tay reedbeds, in eastern Scotland. Over the 2014 breeding season, Tay Ringing Group have been working hard to monitor this important population, ringing an incredible 635 birds - and now these birds are on the move...

The Tay reedbed runs for 15km along the estuary, the largest continuous reedbed in the UK

Around this time last year, Iain Malzer conducted a radio-tracking study of these elusive birds, following them around the reedbed. He was intrigued when he found that none of them moved out of the Tay area during what is assumed to be a traditionally dispersive period. However, this year the picture is quite different. When the population reaches the huge numbers we’ve seen on the Tay this year, ‘Beardies’ sometimes undergo irruptive movements, flying in small flocks in all directions. By understanding the extent and drivers of these movements, we can observe how connected these birds are at a population level, how they remain stable genetically and how they colonise and occupy new areas of reedbed.

Photo (c) Amy Lewis
Typically though, this year Iain didn’t have any trackers on the birds, and so is now asking for help in finding these dispersing birds. As previous Demog Blog posts have suggested, the birds can turn up in the smallest patches of reed, so we are checking everywhere for sightings of colour-ringed birds. Already we’ve had reports from the Isle of May, Aberdeenshire and Loch Leven, but birds can move much further: the longest recovery within the UK was a 390km movement between Suffolk and Devon, and other records have even shown birds moving abroad. This is our chance to record the first long-distance movements from the Tay population.

Many of the birds ringed on the Tay have unique colour-ring combinations, allowing us to identify exactly who they are. Birds may have three colour-rings in any combination of red, orange, green, yellow, light blue, dark blue, white, grey and black. Reports of any sightings, colour-ringed or not, at your local reedbed will be an essential contribution to the understanding of the movement systems of these peculiar birds and their wider conservation.

One of the colour-ringed birds (a female) from the Tay reedbed
To report a sighting drop Iain an email or get in touch with us here at Demog Blog.

So if you're out over the autumn and winter, listen out for the unique ‘pinging’ of Beardies (have a listen on xeno-canto here) and let’s leave no reedbed unchecked.