15 February 2018

The Joy of Nesting Birds

Hazel Evans writes:

This week (14th – 21st February) is the BTO’s 21st National Nest Box Week.  Each year we encourage anyone who is interested, to put up nest boxes locally. I’d like to delve in to some of the different aspects for why this is such a wonderful thing to do, and how we can make the most of them.

The first and most obvious reason is to give birds a place to raise their young. In areas of human habitation it can be harder for birds to find places to nest, so putting up a nest box is a good way to ensure there is somewhere for the birds to use. There are many external factors which may affect the outcome of a nesting attempt, but we can offer them a good place to start. You may also choose to put out some appropriate nesting material in the nearby trees and bushes, or grow some plants to encourage insects. Non-native plants in gardens have been found to be a potential detriment to our local birds, they do not provide as much food, because non-native plants may not be able to host as many caterpillars as native plants, so this may be something to consider.
 
Robin feeding it's young. Photo by John Harding

The second reason why putting up a nest box can be important is monitoring. One of the BTO’s strongest assets is the data it has collected through organising monitoring schemes, and the Nest Record Scheme (NRS) is no exception. Now running for over 75 years, close to two million records of nesting birds throughout the UK have been sent in for over 200 species. This includes data from open nesting birds and nest boxes, both of which are highly valuable. As long as the NRS Code of Conduct is adhered to, we can safely record the progress of nesting attempts by counting the number of eggs and chicks and recording the outcome of the attempt and submitting data to the NRS.

Blue Tit fledgling. Photo by Christine M Matthews

The third reason I value nest boxes very highly, is the intrigue and excitement they can provide. Anyone can put up a nest box and monitor what’s inside it and in turn benefit from watching the behaviour of the birds. Interactions with the natural world have been shown to help relieve depression, anxiety and stress. We are living in a time where it is easy to lose touch with the natural world and many children aren’t getting experiences with nature; having a nest box in your garden is an inspiring way to learn about the natural world. Monitoring nests is not something that should be taken lightly but with the knowledge that the data is going to a good cause, it's something we can experience great joy from.

Now is the time when garden birds are just starting to prospect nesting sites in preparation for the approaching spring, so the sooner you can get a box up the better, whether you build it yourself or buy it from the garden centre. There are many bird species which use nest boxes, so if you have a bit more space then you may want to put up a larger nest box, for a Kestrel or owls.

Once used, it is a great idea to clean out old nests the following winter to allow for a fresh start in the spring. To comply with legislation, nests should only be cleaned out between 1 August and 31 January.

01 February 2018

Brit abroad causing a stir

The species, or subspecies, of the Redpoll complex has long been something that birders and ringers have debated; the use of new advances in technology, like sonograms and DNA studies, have only fueled the discussions. There are currently three recognised species, Lesser, Common (Mealy) and Arctic Redpoll, with subspecies also acknowledged (depending on which criteria you use). Identification of these species can be difficult; however, ringers are in the privilaged position of being able to collect detailed data on size (wing length) and plumage to help inform the decision.

Since 2010, the average number of Lesser Redpoll ringed by the BTO Ringing Scheme is 21,000 birds per year. The number of these that are later relocated is quite high in comparison to similar species. They have become increasingly common in gardens (as recorded through Garden BirdWatch) possibly due to garden bird feeding; this also offers additional opportunities for ringers to catch these birds.


https://app.bto.org/ring/countyrec/resultsall/rec16634all.htm
Colour of location: Ringed in Britain and Ireland, Found HereRinged Here, Found in Britain and Ireland

The map above shows the ringing and finding locations for all the Lesser Redpolls that have been ringed or reported in Britain and Ireland. This map will have to be redrawn later this year however, as we have now received details of a bird that had its metal ring read in Spain! During 2017, there were only two sightings of Redpoll in the whole of Spain, so 20 January 2018, when a flock of 15-17 birds turned up, was an exciting day; it was made even more exciting by the fact that one of the birds was wearing a ring!


Adult male Lesser Redpoll. Photo by Jesús Mari Lekuona

Unfortuantely, as the rings on Redpoll are very small, it is very difficult to read the ring number in the field; however, Jesús Mari Lekuona managed to read all but the last number. This narrowed the options down to 10 possible birds, and all of them were Lesser Redpolls of various ages (adult or juvenile), ringed on 14 October 2017 near Cinderford, Gloucestershire by Robin Husbands. As you can see from the photo, this bird is an adult male... and this matched a single bird, ringed at 12.30!

This is the most-southerly recovery of a Lesser Redpoll, although there is a report of a 'Redpoll species' recorded in Portugal (before they were split into three species). In countries where certain species rarely occur, finding a bird with a ring can be really helpful, not only to increase our understanding of bird movements, but also to help validate such an unusual movement.

Thanks to Jesús Mari Lekuona, Ricardo Rodríguez, Jorge Nubla, Oscar Guindano and Jose Ardaiz for getting the ring number and Rare Birds In Spain for letting us know.

19 January 2018

Ringing and recoveries roundup

From all in the Ringing and Nest Recording Team, we wish you a Happy New Year!

This is a very busy time of year for us. Ringers all over Britain and Ireland are submitting their 2017 ringing data before their ringing permits can be renewed. The graph below shows when the data were submitted for birds ringed in 2017, and the number of birds in each data load.

Number of ringed birds submitted to BTO. Click to enlarge graph.

The deadline for submitting records isn't until the end of Febuary, but even so, it looks unlikely that we will reach a million birds ringed this year. At the moment Blue Tit is the most-ringed bird with 102,716 ringed, followed by Goldfinch (53,993), Great Tit (53,395), Blackcap (51,806), Chiffchaff (49,801) and then Siskin (33,812).

One of the many male Great Tits ringed. Photo by lee Barber

As the data come in, we also receive the details of BTO-ringed birds which have been reported away from the place of ringing. Here are some interesting recoveries that have turned up so far this year.

A Chiffchaff ringed at Snettisham, Norfolk on 24 September 2016 was recaptured at Gwennap, Cornwall on 6 January 2018 (489 km). A Goldcrest got a bit too close to a cat on 9 January at South Elmsall, Pontefract after being ringed at Heysham Harbour, Lancashire on 19 September 2017 (118 km). An unfortunate Lesser Redpoll was found after falling prey to an unknown predator at Oudon, Nantes, France. It had been ringed near Darlington, Stockton-on-Tees (805 km); strangely, the ringing and finding dates are exactly the same as those of the Goldcrest. On a lighter note, an Oystercatcher was seen at Dawlish Warren, Devon on 4 January; this individual was ringed at Holbeach St Matthew on 31 August 1999 (353 km).

Male Goldcrest. Photo by Lee Barber

Last week we received a report of a ring being 'found in a drawer' in Tennessee, US on 7 January 2018. A BTO ring being found in America is always a special event, but while processing the details, we realised we already had a report of this bird on the system. It actually died in 2005 (4.5 months after ringing). This ring was put on a female Canada Goose at Llangorse Lake, Powys... and was shot at St Johns, Worcester, 77 km away, and reported by someone who lived near Llanelli, Camarthenshire. It is amazing to see how far a ring can travel without the bird.

Thanks to all our ringers and nest recorders for doing such great work; without them this information would be impossible.

21 December 2017

Return of the winter Blackcaps - a geolocator story

How do migratory birds respond to a changing environment? The answer to this question may help us unlock key insights into the mechanisms behind migration, and predict how animals will adjust to future global change. British Blackcaps may provide key insights into birds’ abilities to evolve changes in migration. Blackcaps are now spending the winter in the Britain and Ireland in greater numbers than ever before - a change BTO scientists have linked to garden feeding and warmer temperatures. But what exactly do they gain by wintering here, and where are they coming from?

Blackcap with first geolocator retrieved - photo by Benjamin Van Doren

As previously reported, last year, researchers from the BTO, Oxford University, and Exeter University began teaming up with bird ringers and garden owners across Britain and Ireland to study the Blackcaps that visit our gardens in winter. Last winter, we fitted 36 Blackcaps with geolocators, miniature devices that track movements throughout the year; however, the birds must be recaptured in order to retrieve the device and data, which can be a challenge.

Excitingly, returning Blackcaps carrying geolocators have been seen in gardens around the country since late November. These early successes would not have been possible without the dedicated BTO ringers, Garden BirdWatch participants, and other volunteers who have contributed so much time and effort to the ongoing study.

Blackcap geolocator movements. Blue dot - wintering site.

On 26 November, Glynne Evans recaptured the first returning individual in his Hampshire garden where it was tagged nine months earlier. Preliminary analysis indicates that the bird left Britain at the end of March and spent the summer in France, before returning by early November. But is this pattern the exception, or the rule? And why did this bird decide to come north for the winter when it was already in southern France? We hope to find the answers to these questions and many others - as the project continues.

Garden ideal for Blackcaps - photo by Benjamin Van Doren

Glynne’s GBW garden has turned out to be an exceptional Blackcap site, with a further tagged bird (analysis in progress) being caught in December, as well as two other colour-ringed birds returning from last year, giving a return rate of 25%, so far. We know very little about their behaviour and movements in winter, so any sightings of colour-ringed birds would also help answer these questions. Glynne provides food for Blackcaps starting relatively early on in autumn—could this partially explain their affinity for his garden?

How can you help? 

Do you have Blackcaps visiting your garden in winter? Look out for Blackcaps with colour rings and note the positions of the colours on each leg, or even better, take a photograph. Observers interested in joining the colour-ringing and tracking efforts can contact Benjamin Van Doren at Oxford (benjamin.vandoren@zoo.ox.ac.uk) or Greg Conway at the BTO (greg.conway@bto.org). Gardens with multiple Blackcaps regularly attending bird feeders are particularly valuable. For further information please see Life Cycle, issue 6 Autumn 2017.

This study is a collaboration between Oxford University, BTO, Exeter University and the Max Planck Institute for Evolutionary Biology, Germany.

28 November 2017

The Barra Sparra

Ian Thompson, Yvonne Benting and Bill Neill write:

We have been colour ringing House Sparrows here in Askernish, South Uist as part of the BTO’s RAS scheme for the past seven years. Because House Sparrows have a reputation as being difficult to catch and retrap, the use of colour rings was a conscious decision on our part. This enabled us to identify the birds individually in the field, but more importantly, it allowed our neighbour to participate in the project by recording the birds that visited his garden.

Female House Sparrow. Photo by Ian Thompson

While the House Sparrow RAS season runs from April – August, we observe and record our birds all year round. Again, the use of colour rings has allowed us an insight into their movements around our islands and this has surprised us as to how far ranging they can be. We now receive regular updates from several observers around the islands, and the birds have been recorded as far north as Balranald, North Uist (46 km) and as far south as South Glendale, South Uist (11 km).

To date, all these movements have been within what is known as “the long islands”, which are all joined by causeways, and none have yet travelled over water. With two birders having recently moved to the Isle of Barra, we began hoping that one of our birds might turn up there.

Recently we had been seeing three unringed birds (two male, one female) amongst our regulars and favourable weather gave us the opportunity to try to trap them. Over a period of two weeks, we trapped and ringed 12 new birds (seven female, five male) and we still had four unringed birds (two male two female).

But, amongst the 12 was a bird we hadn't originally ringed (control)!

After a few enquiries, we found that the bird had been ringed by Mark Oksien earlier this year on 18 September at Garrygall, Barra (see map below). Not only has this bird moved 26 km, this is the first time we have recorded a House Sparrow crossing water to other islands. After such a long wait, this was not the way it was meant to happen. We expected that it would be one of our colour ringed birds turning up in Barra, not the other way round.


As Bruce Taylor, one of the Barra birders commented  “the way Calmac has operated of late, we can rule out ship assistance”.

This House Sparrow has since become known as the “Barra Sparra”.

Note:- None of the 12 Sparrows that were ringed have been seen since.

We had news yesterday (27 Nov 2017) of another sparrow making the reverse trip! A bird I ringed on 7 Nov 2017 (O54) turned up in Bruce Taylor’s garden yesterday (one of the birders on Barra) at Brevig, Barra. It would seem that we have quite a movement of sparrows here in this bout of hard weather.

House Sparrow O54. Photo by Bruce Taylor

Information and regular updates on our project and sightings of our birds can be found on the Outer Hebrides Birds website or by following this link.