31 January 2013

Hola Great Black-backed Gull

We recently received the following snippet of news from Euan Ferguson (Grampian Ringing Group):

A couple of months ago we blogged about the unusual colour ring sighting of a Common Gull chick seen in North West Spain (Hola Common Gull). We have now had another gull chick (bizarrely ringed on the same day!) sighted in Spain only 7 miles away from our Common Gull; however this time it is a Great Black-backed Gull.

On the 30th June 2012, after a morning ringing 180 Common Gull chicks on moorland, we headed to Whinnyfold seabird colony. Here we ringed 90 gull chicks on a tidal stack (above), most of which were Herring Gulls, but we also colour-ringed three Great Black-backed Gulls (below); the first chicks of this species to be ringed in our project.

We heard nothing more of these birds until 13th January, when T:013 was reported from Ares beach, A Coruña, Spain (below). What makes this sighting more interesting is that very few British-ringed Great Black-backed Gulls are reported in southern Europe. According to the BTO's online ringing report, only three individuals have previously been recorded in Spain, and one in Portugal. The majority of birds found abroad are in Scandinavia.

So far in our project we've mainly colour-ringed Herring and Lesser Black-backed Gulls, with only 16 Great Black-backed Gulls ringed to date. But despite this small number, we have received three foreign sightings of other birds ringed on the same day; one in Germany and two in Denmark. Such a high return rate from so few birds ringed really demonstrates the value of colour rings on this species.

All large gulls ringed in North East Scotland are fitted with a yellow colour ring on the left leg, starting with T: and followed by three numbers or two numbers and a letter. Please report sightings to e.ferguson17@hotmail.co.uk

Thanks to Euan for letting us know about this and providing Scottish photos and to Antonio Gutierrez for the photo of T:013 in Spain.

25 January 2013

How do you like your eggs? Frozen

The start of each year sees some pretty intense competition between BTO staff – who will be first to see a rarity on the Nunnery Lakes (generally Nick Moran), who will have the highest list at the end of January (Nick, again), who will catch the most Siskins (Allison Kew, with Greg Conway or Graham Austin a close second), etc, etc. From my point of view, the greatest accolade is the first active nest found of the year and it’s fair to say that I’m usually in the running, poking about in gorse from the end of February for nascent Long-tailed Tit nests or scouring the rivers and reedbeds for early Mallard and Moorhen clutches. The ideal target species would be Crossbill, our earliest breeding songbird, were it not for the fact that to nests right at the top of tall pine trees and I don’t exactly have the best head for heights (or the physique for climbing, these days).

Spot the nest

This year, however, I have been kicked into touch by BTO Press Officer Paul Stancliffe, who located the first Thetford nest of 2013 before I’ve even started looking. On 19th January, amidst the snow covered wastelands of the town centre, Paul spotted a Collared Dove sitting on a nest lodged at the top of a telegraph pole. The bird was still sitting the next day, and on the 22nd he was able to see into the uncovered nest from his upstairs bedroom window, glimpsing the top of at least one egg. It is now the 24th and the bird is still incubating in the sub-zero temperatures.

First nest record of the year for Thetford

Collared Doves are extremely opportunistic breeders. Data from the Nest Record Scheme show that nesting has been recorded in all months of the year (sample size c. 4,200 records). The peak month in terms of clutch initiation (the laying of the first egg) is April (Figure 1), and the main season is typically from March to July. This is earlier than Woodpigeon which again can be found nesting in most months, but exhibits a peak in laying between July and September.

Figure 1

The current cold snap doesn’t really seem to present much of an opportunity, however, and I fear that the outcome of this attempt is unlikely to be positive. We shall continue monitoring their progress to find out.

Dave Leech

21 January 2013

Detailed Common Sandpiper movements discovered

We've had a number of recoveries of Common Sandpiper on migration and on the wintering grounds over the years including Algeria, Morocco, Italy and Guinea Bissau. The distribution can be seen on the map below (purple - ringed in Britain Ireland, yellow - ringing location of birds later found in Britain or Ireland).

However, we now have more information from a study by Highland Ringing Group ringers which investigated the pre-migratory change in mass and the migration route of Common Sandpipers in 2011. Some of these birds were fitted with geolocators in Highland, Scotland, which logged the approximate location of each bird using a combination of time and day length.

They write:
"One bird left Britain on 21 July and migrated for three days to Morocco where it staged before continuing its migration to W Africa for the non-breeding season, arriving on 29 July. The region in which it spent most of the non-breeding season (Oct–Feb) was S Senegal or The Gambia.
Prior to northward migration, the bird spent a period inland, before crossing the W Sahara desert to Morocco. Its migration was then delayed, probably due to adverse weather (strong NW winds). However, after a week in Morocco, which involved some northward movement, it followed the east coast of Spain and crossed to W France before moving through England to Scotland. Although Common Sandpipers can accumulate sufficient stores for a long single non-stop flight between N Europe and W Africa, the focal bird migrated in medium-range “skips” during both its southward
and northward migrations."

This is the first record of a British-breeding Common Sandpiper on its wintering ground south of the Sahara. The earlier record in Guinea Bissau referred to a bird on migration, so its origin was unknown.

Thanks to Brian Bates, Brian Etheridge, Norman Elkins, James Fox & Ron Summers for conducting this fascinating study. For more information on the International Wader Study Group click here.

14 January 2013

Inner London's first Beardies

We recently received details via Des McKenzie of two ringed Bearded Tits currently residing in a bus-stop-sized reedbed in Hyde Park, London. These birds (both females) are actually the first records for the inner London area so caused quite a stir when they first appeared. Full details of their convoluted arrival are on Dominic Mitchell's blog and some images of the ring can be found on the Wanstead Birder blog.

Being such a draw in the capital ensured that these birds were well-photographed (the above from Chris Hinton) and after a bit of detective work (and jigsaw-puzzling), Andy Moon managed to piece together the full ring numbers. Bearded Tits often seem to travel in small groups, so it was perhaps not surprising that these birds had been ringed together, and with consecutive ring numbers.

L511927 and L511928 were originally ringed on 10th November 2012, 32km north of Hyde Park at Rye Meads, Hoddesdon. They were caught along with a single male, but weren't seen again after release, but there was a report of two females from Amwell on 14th November. Prior to that the last Bearded Tits ringed at Rye Meads was in 2002, although a ringed male was recaught there in February 2011, having been originally ringed at Haddiscoe Island, Norfolk.

Thanks to Des McKenzie for piecing the numbers together, Chris Hinton for the photo and Chris Dee (Rye Meads Ringing Group) for the ringing details.

04 January 2013

London bus Arctic Skuas and an exceptional Marsh Harrier

Recoveries of Arctic Skuas in the southern hemisphere are rather unusual, with the furthest south being five reports of birds found in South Africa. The map below shows where our Arctic Skuas have been found, taken from the BTO's online ringing report.

So whilst the report of one picked up sick in Plettenburg Bay, in the Western Cape Province of South Africa, on 8th December was notable, the fact that another was found dead less than 10km away on 24th December is quite remarkable. One can only wonder what weather conditions had caused these birds to be found so close to each other so far from home.

Even more bizarre is that both of these birds were ringed as chicks on Foula, Shetland. These weren't unfortunate lost immatures bird either, having been ringed in 1993 and 1995!

Of equal note was the report of a wing-tagged Marsh Harrier in Portugal on Christmas Day. Seen alive and well, this Norfolk-ringed bird (seen just after ringing below) is just the second to be 'recovered' in Portugal, following a Suffolk-ringed bird found dead there in 1986. Check out where others have been found online.

Thanks to Phil Littler for the harrier news and photo of the team in action.