24 July 2017

From the land of ice and Blackcaps

For Hugh Insley, ringing at this time of year means trying to catch Siskins in his garden in Drummond, Inverness for his Retrapping Adults for Survival (RAS) project and so far this year he has caught 3,000. Inevitably, he also catches a few other birds which are not part of his RAS project.

On 11 July, he extracted a Blackcap from the net that was already wearing a ring. This wasn't one of the c. 50,000 that are ringed in Britain or Ireland every year though, but the first record of a Blackcap that was ringed in Iceland! Now the BTO has to add a new row to the long list of countries that Blackcaps have come from or have gone to with a connection to our ringing scheme.

Female Blackcap wearing an Icelandic ring. Photo by Hugh Insley.

As we have posted previously, Blackcaps have a very interesting and complex migration, possibly associated with climate change and supplementary feeding, which is currently being studied. Many of our British & Irish breeding birds are known to winter in the south, around Spain and Portugal, whilst those that now winter here are known to come from continental Europe - using a novel northwest migration rather than the typical southwest route to reach Iberia. 

The individual that Hugh caught was ringed on 3 November 2016 as a full grown adult female in the garden of the vicarage at Siglufjordur, N. Iceland (see the blue pin below). It was caught again twice more at the same location (on 20 January and 30 March 2017) before heading south to Inverness.



Blackcaps are a vagrant species in Iceland and only 222 have been ringed there; only five of these have been caught again in the country. Additionally, eight Blackcaps that were ringed abroad (five from Belgium and one each from Denmark, The Netherlands and France) have been caught in Iceland. 
 
So, was this a 'British bird' making a novel northwest instead of southwesterly (mirror-image migration) before returning to breed, or was it part of a wider northward movement now undertaken by central European Blackcaps into northern Europe?  

07 July 2017

Who gives a hoot

Occurring throughout England, Scotland and Wales the Tawny Owl is well known, especially during the winter when their territorial calls can be heard during the night.

The Tawny Owl is amber listed, i.e. a species of medium conservation concern due to recent population declines. Surveying this species can be difficult, but studying them is easier due to their readiness to use nestboxes. Ringing the adults and their chicks, as well as following the progression of the nesting attempt (nest record), provides very useful information to help interpret population changes.
 

Adult Tawny Owl. Photo by Rachael Barber


Adult Tawny Owl with a more grey plumage. Photo by Lee Barber

The number of Tawny Owls ringed each year varies considerably; in the last five years the number ringed has ranged from 920 to 2,748 birds. The number ringed also varies by county, with ringers in Northumberland topping the list with an average of 183 birds per year. This is followed by Lincolnshire (107), North Yorkshire (100), Nottinghamshire (92), Norfolk (81) and Cumbria (81). Around 80% of the birds ringed each year are chicks. Ringing chicks enables researchers to follow an individual throughout its lifetime, providing vital information on where birds move to and exactly how long they live.

Tawny Owl chicks. Photo by Lee Barber

For most of the recoveries the BTO receive, the cause of death is unknown, but for some the cause of death is clear. Being hit by a vehicle is the most reported cause of death for Tawny Owls, followed by train casualty and drowning in artificial water containers like horse or cattle troughs. This doesn’t mean that 66% of all Tawny Owls die from vehicle strikes, however. Birds killed by vehicles are inevitably more visible than a bird that dies of natural causes in the middle of a wood. Also, as most of the birds that are reported are from areas with high concentrations of people, these are more likely to be reported when found.


By recapturing ringed birds, licenced bird ringers are in the privileged position to be able to gather information on the presence and condition of Tawny Owls that are alive and well. Last year one of our ringers re-caught a Tawny Owl that was originally ringed as long ago as 2003. This bird was ringed as a chick and re-caught in the same place (Kielder Forest, Northumberland), so the exact age of this bird is known (13 years). A bird ringed in 2004 at Rowlands Gill in Tyne and Wear which was also caught during 2016, that was an adult (at least 1 year old) so she could have been much older. It would have been doing very well to break the longevity record of 21 years 10 months.

Unlike some other owl species, Tawny Owls doesn’t generally travel very far or cross large bodies of water, so their distribution is restricted to mainland Britain.  Due to this behaviour we have had no foreign recoveries in the history of the BTO Ringing Scheme.

Tawny Owl chick about to be ringed. Photo by Lee Barber

I have received one recovery while working at the BTO, of a ring found in Iceland (without a bird) which was originally put on a Tawny Owl chick. This was an amazing record so (as with all our recoveries) some investigation followed. Unfortunately, this wasn’t quite as amazing as we’d hoped as we had a previous record that this bird had already died. The ‘used’ ring was put on a binocular strap for safe keeping after reporting. Some years later the finder was on holiday in Iceland when the strap broke and the ring was lost, only to be found later by someone else who reported it to the BTO via www.ring.ac.

The vast majority of data from ringing and the resulting finding of dead birds can provide an amazing amount of information, so if you do find a ringed bird please report it via www.ring.ac.  As a thank you, you will receive the information on where and when the bird was ringed.

15 June 2017

Nest Recording Taster Day, Glamorgan

‘Fledgemore’ is a new nest recording group in Glamorgan. Established in 2015, its members (Andy Bevan, Trevor Fletcher, Dan Jenkins-Jones, Wayne Morris and Graham Williams) have only been nest recording for a few years but, as well as finding and monitoring their own nests, one of their ambitions is to increase the number of local recorders contributing to the BTO’s Nest Record Scheme (NRS). They’ve written this blog about one of the ways they’re doing that.

Nest recorders will tell you that finding and then monitoring nests for the NRS is one of the most challenging, exciting and fulfilling experiences in birding. There’s something new to learn every year, there’s the thrill of finding a new nest and there’s the satisfaction in knowing that you’re gathering vital data for the BTO’s Ringing and Nest Recording Team that will inform birds’ long-term conservation.

There has been a welcome increase in the number of nest records submitted from across Britain & Ireland in recent years. An increase that has been reflected in the totals from our home county of Glamorgan. Up until 2006, barely 100 records a year were being sent from here to the BTO. In 2015, that figure had risen to almost 800. But, when we scratched beneath the surface, we found that there were no more than eight or nine birders regularly contributing nest records from Glamorgan. We’re sure other regions have a similar situation.

Blackbird chicks close to fledging at Rudry (Photo: Dan Jenkins-Jones)

If you’re new to nest recording you can learn a lot about how to find and safely monitor the nests of various species from books and online articles, but nothing beats a first-hand experience in the field with other nest recorders. This is how we learnt to find our first nests and it gave us the leg up we needed. With this mind, we trialled a ‘Nest Record Scheme Taster Day’ at Rudry Common, north of Cardiff, in 2016 in an attempt to increase the number of local recorders and put the Scheme on a more sustainable footing in the county. Despite having no more than five seasons’ nest recording experience ourselves, we felt we had sufficient knowledge to be able to share the basic skills with newcomers and to hopefully enthuse and encourage them to take up nest recording. Five birders took part in that event, two of whom are now members of Fledgemore with 130+ nest records gathered between them so far in 2017! Encouraged by our experiences of this ‘Taster Day’, we held another at Rudry on 14 May this year.

Taster Day 2 started with a short indoor session where we presented the participants with their free hazel ‘tapping stick’ and ‘mirror on a stick’, kindly donated by the Rudry Common Trust and both essential tools of the nest recorder’s trade, which they learnt to use during the day. We introduced them to the NRS Code of Conduct, to some basic nest finding techniques and then we were soon out in the field for six hours of ‘nesting’.

Using a mirror on a stick to examine nests (Photo: Graham Williams)

Seeing a bird’s nest which contains eggs or chicks can be that spark which ignites an individual’s fascination with nest recording – especially if it’s a nest you’ve found yourself. To ensure we’d be able to provide that experience, Trevor recced the area in advance of the event and found a nice variety of nests to show everybody.

We spent the morning working through woodland, finding a number of nests: a Blackbird nest with chicks close to fledging; an active Goldcrest nest and, later, a predated one; Great Spotted Woodpecker with chicks; Song Thrush and a Wren on eggs; a Woodpigeon nest which had sadly failed at the chicks stage; a Blue Tit in a nestbox and Coal Tit and Great Tit with chicks nesting in natural cavities, both of whom enabled Trevor to show off his skills with an endoscope. A number of old nests were found too, which are useful in showing participants the likely places to look for nests in future.

Two of the participants trying out the art of ‘tapping’ for the first time (Photo: Andy Bevan)

Late morning, we left the woodland and moved out onto to Rudry Common in search of a suite of different species. A Linnet nest in gorse, which contained chicks a few days before the Taster Day, was sadly empty, probably lost to predation. Nevertheless, it enabled the participants to get a feel for where to find their own Linnet nests in future. A beautiful Long-tailed Tit nest with chicks, also in gorse, was up next, followed by a well concealed Meadow Pipit with four eggs.

The highlight of the day for most was probably a Willow Warbler nest with eggs, described by one participant as a ‘nest on its side’. It’s such a simple, yet beautiful, construction and superbly camouflaged. Finding one is always a thrill, and yet, with the right fieldcraft and knowing how the female’s off-nest call will help you, finding a Willow Warbler nest can be quite easy.

Willow Warbler nest on Rudry Common (Photo Dan Jenkins-Jones)

Best of all, some of these nests were found by the participants, either by ‘watching birds back’ to their nests or, on one occasion, a Blackbird on four eggs was found by gently ‘tapping’ suitable habitat with a hazel stick which gently flushed the sitting bird. Finding these nests and recording their contents generated a lot of excitement amongst us all. For the participants, it proved very quickly that they could find their own nests, and for us as leaders it was great to be able to show that the tips we’d shared with everybody actually work!

The day was rounded off with another short indoor session where we shared information on how to plan nest visits and what information to gather at the nest: egg or chick counts; nest location and habitat; chicks’ feather structure; the nest’s ‘outcome’ etc.  Finally we ‘crowned’ Tara, one of the participants who found three nests as the ‘New Nest Finder of the Day’. Tara went on to justify her crown by returning to Rudry Common immediately after the event to try and find a Garden Warbler for her Year List, and found another Willow Warbler nest on her own!

Tara was crowned ‘Nest Finder of the Day (Photo: Rob Williams)

An enjoyable day all round and we’ve heard from some of the participants that they’ve already been finding their own nests. Fingers crossed that some, if not all of them turn out to be fully-fledged nest recorders in years to come. And of course, we found some new nests on the day to add to our own monitoring for the Scheme. The BTO is keen to encourage ringers to contribute data to the Nest Record Scheme and, where possible, we are revisiting nests to ring pulli to further contribute data to the Ringing and Nest Recording Team. 

We’d highly recommend other nest recorders hosting similar events in their own regions to build up the numbers of local recorders. You definitely don’t need years of experience behind you, you’ll introduce others to a fascinating aspect of birding, help the Nest Record Scheme get even more records and you’ll enjoy every minute of it.

30 May 2017

Drift migration in action

Following a brisk overnight easterly wind, hopes were high on the morning of 12th May for a few drift migrants arriving at Isle of May Bird Observatory in the Firth of Forth. The highlight was a stunning male Red-breasted Flycatcher found on the beach at Pilgrims Haven, soon drawing a fair crowd (by island standards). It was quickly noticed that the bird was ringed, and knowing it hadn't been ringed on the island, attempts were made to read the ring from photographs. The ring inscription looked foreign, but unfortunately the ring number itself couldn't be read.


So the bird was left to feed for a couple of hours, before ringers returned with a single-shelf net and just minutes later the bird was caught, revealing the ring was from the Swedish Ringing Scheme. After processing, the bird was released in the same spot and was still present the next day.

Being such an unusual record (we've only ever seen one previous foreign-ringed Red-breasted Flycatcher in the UK - details here), a quick flurry of emails back and forth across the North Sea soon revealed the details. TV0721 was ringed just a week earlier (5th May) at Torhamn in southern Sweden. It had presumably been caught up in an area of high pressure over northern Europe, creating an easterly airflow across the region. The synoptic chart (below) for 11th May also shows the ringing and finding locations, some 1,175km apart!


When ringed, the bird weighed 10.0g and a week later 9.7g, so rather than being thought of as a lost vagrant, it should perhaps be considered a drift migrant, carried on the wind on its migration north. Red-breasted Flycatcher breeds from eastern Europe across to the Himalayas, wintering in southern Asia, although it was long been suggested that there may also be a wintering population in west Africa.

Previous recoveries in the UK have all been in autumn, although one record did see a bird ringed on Shetland recaught in southwest Norway two weeks later!

##UPDATE##
Many thanks to Anders Loell who got in touch with some background (and a photo) on the ringing of this bird: "I had the pleasure of finding it in a net here at Torhamn. And as you suspected there were some heavy eastern winds. There were only two nets possible to use on the 5th and the only reason why they were active was due to some schoolkids coming out here to visit the observatory."


10 May 2017

Reading the small print

Within the ringing team, it never ceases to amaze us just how many people spend their time reading bird rings. Only a small percentage of ringed birds are colour ringed as well, so most birds can only be identified by reading the metal ring number, which can be difficult with wild birds. Rings on large birds such as swans and geese can be quite easy to read, due to the ring size and the proximity of the birds in parks and lakes.

Mute Swan account for 44% of all the metal ring reads (sample from 1 Jan 2017 to today), followed by Black-headed Gull with 19% and Shelduck with 5%. The remaining reports are between 57 different species ranging from sea birds like Puffin and Cormorant to passerines like Nuthatch, Goldcrest, Lesser Redpoll and Grasshopper Warbler.


Last week we had a report of a Green-winged Teal (below) at Storavan, Stöcke, Västerbotten, Sweden wearing a BTO ring! Luckily for Johan Forssell and Mikael Wikstrom, very few Green-winged Teal are ringed by our ringing scheme (see ringing totals by species), so finding a match with the given numbers was relatively easy. This bird was ringed as an adult male on 6 Oct 2015 at Caelaverock, Dumfries and Galloway (1,651 km). For more information on the recoveries of Green-winged Teal see our Online ringing reports (don't expect to be overwhelmed by numbers).

BTO ringed Green-winged Teal (foreground). Photo by Johan Forssell




Bardsey Bird Observatory was lucky enough to ring a Pallas's Warbler on 18 April 2017, making this the first spring record for Wales. In fact, this is probably only the third spring record of Pallas's Warbler in the history of our ringing scheme. This bird soon moved away, however a ringed Pallas's Warbler was seen on the island on 7 May.

Pallas's Warbler. Photo by Steve Stansfield in May

Being a very popular bird, this bird was photographed in enough clarity that five of the six digits could be read. This size of ring also fits on Goldcrest and Wren, so is very small indeed. There was only one issue... the ring number didn't match the one that was put on the Pallas's Warbler in April. This was a different bird!

Pallas's Warbler. Photo by Steve Stansfield in May


With the help of the BTO's national ringing scheme database, the origin of this bird was traced. It was originally ringed at Spurn Bird Observatory on 11 Oct 2016! Re-catching a ringed Pallas's Warbler at a different site is incredibly rare, so the details of where this species goes after it reaches our shores is now a little clearer, but there is still a long way to go to fully understand their migration.

Learning to become a ringer takes quite a lot of commitment and time. As these and other previous examples highlight, you don't need to be a ringer to make a real difference to our knowledge of bird demography.