13 September 2017

Record breakers of the bird world

Bird ringing has come a long way since it's inception in 1909. It was primarily set up to answer some basic questions, like where do our birds go and how long do they live. Since then, an amazing amount of information has been gathered that answers many more complex questions, like why a certain species population changes each year and where in Britain or Ireland are they declining. More information can be found on the BirdTrends and ringing surveys pages.

https://www.bto.org/volunteer-surveys/ringing/surveys/ras

 https://www.bto.org/volunteer-surveys/ringing/surveys/ces

At this time of year, all of the previous year's data have been loaded and checked and the Ringing and Nest Recording Team pull together some of this information to produce the Online Ringing & Nest Recording Report. The report includes annual totals for ringing and nest recording, as well as information on recoveries, but it also covers one basic question... how long can a bird live?

The longevity records for 2016 have now been updated and there are some interesting new records. Relatively new colonists like the Little Egret often feature. As they have only been ringed in any numbers in Britain and Ireland in the last fifteen years, we probably haven't yet established the normal maximum life expectancy; the record currently stands at 10 years and five months.

Little Egret chicks. Photo by Graham Giddens
Last year saw 17 records broken including three owl species; Barn Owl, Little Owl and Tawny Owl with ages reaching 15 years, 13 years and 23 years respectively. Some finches also did well with Twite, Lesser Redpoll reaching six years and Goldfinch reaching 10 years.

Lots of these record breakers were caught by a ringer, as opposed to being found dead or being identified by colour marks. Where ringers monitor the same populations annually, the potential for individuals to be caught again increases. This is exactly what happened with three of the record breakers, Little Ringed Plover, Peregrine and Nuthatch, which broke their own records after being re-encountered in 2016! 

The Puffin longevity record was broken again in 2016, and the oldest-known bird in Britain or Ireland is now a ripe old age of 37 years. The individual that broke the record, seen in the photo below, was ringed and re-encountered by the Shiants Auk Ringing Group, who ring in the Western Isles. The previous record holder was also a bird from the Shiants.

The oldest-known BTO-ringed Puffin, by Liz Scott.

We won't be analysing the 2017 records until next year but we already know that the current longevity record for Jackdaw has been broken. Originally ringed in April 1999 by Declan Manley, and subsequently re-caught in 2005, 2007, 2012 and now in 2017. A Goldfinch ringed in Nottinghamshire and found dead in Devon has also broken the 2016 longevity, adding another couple of months on to the current record.

Longevity records are the maximum a species has been recorded to live but most birds do not manage to reach this age. The average life expectancy and lots of other interesting facts can be found on our BirdFacts page.

04 September 2017

White bred Sandwich Tern

Ewan Weston from the Grampian Ringing Group writes:

On 19 June, Grampian Ringing Group carried out some colour ringing at the Sandwich Tern colony in the Sands of Forvie NNR, Aberdeenshire. The group has a long running study on the species to gather information on survival, recruitment and movements. While rounding up some of the young for ringing, one eagle eyed trainee spotted a pure white chick amongst the regular coloured chicks. This bird was colour ringed, although we were not hugely hopeful of the prospects for a white bird as it would be more noticeable to predators. The photos of the chick were sent to an expert who suggested the bird was probably not an albino, but has the recessive Ino mutation, which results in very poor oxidation of melanin.

White Sandwich Tern and birds in regular plumage. Photo by John Tymon.

Since ringing, we have had several sightings, initially as this distinctive bird migrated down the east coast of Scotland and then over on the west coast of England at Ainsdale beach in Merseyside where it has spent a few weeks. Several people have sent us photographs of it and it has turned into a truly magnificent tern.

Flying alongside a 'normal' Sandwich Tern. Photo by John Tymon.

From this colour ringing project, over the last few years we have found that once birds leave their breeding sites they spend several months on the UK coast (often north of their breeding sites) before heading south to winter predominantly in Africa. Very few Sandwich Terns return to Europe in their second summer, with most only migrating back to Europe in their third or fourth summer. It will be quite a long wait to see if this bird returns to Scotland in a few years time to breed, but if it does I am sure it will be seen.

As this project highlights, sightings of colour marked birds have helped increase our knowledge of the movements and behaviours of many species, not just Sandwich Terns. So, if you see a colour marked bird (or find a bird fitted with just a metal ring), please report it at www.ring.ac.

16 August 2017

See you at Rutland Birdfair

It's that time of year again, when birders from all over the world gather at their 'Glasonbury' - The Birdfair.

Over the years, the Birdfair has raised mind boggling sums of money for bird conservation all over the world. Many wildlife charities attend to help with this cause and promote their charity at the same time. The BTO has attended the Birdfair for many years and this year is no exception, so when you are there, pop over to marquee three (stand 36-38) and say 'Hi'. It would be great to meet our many thousands of volunteers and members and we can let you know what has been going on at BTO HQ recently.

For the Ringing and Nest Recording Team, the pinnacle of the Birdfair has to be the ringing demonstration, run in partnership with the Rutland Water Ringing Group. We're in the same place as previous years, which is next to marquee four and the red car park. Over the years we've had some fantastic birds including Kingfisher, Sparrowhawk, Turtle Dove and Nightingale, but it's not all about the rarely caught birds. All the data collected during Birdfair will go into the BTO national ringing database and supplement all the fantastic work done by the Rutland Water Ringing Group.

Ringing demo in action. Photo by Sam Franks

Our main species caught are Reed and Sedge Warblers, some of which have been ringed in previous years, and now have clocked up quite a few miles during their life by going to Africa and back. Once we have processed all the birds, our attention switches to ringing people. If you are 'ringed' with one of our wrist bands, pop over to the BTO stand (marquee three) to find out what happened to you.

Releasing a Dunnock. Photo by Peter Carr (@wildlifePete)
There is a lot to do at Birdfair, but make sure you visit us at the ringing demo and the main BTO stand, as it would be great to see you (we may have a small slice of cake for you too).

02 August 2017

Chick couldn't wait to get to Britain

Gull spotter Andy Deighton writes:

Norfolk Bridge, on the river Don in Sheffield, has been a good place to get close views of loafing gulls over the summer. The birds feed at the nearby Viridor glass recycling plant and loaf, bathe and preen on the river weir and adjacent factory roofs.

Decent numbers of immature Lesser Black-backed Gulls and Black-headed Gulls spend late summer here, with smaller numbers of Herring Gulls, the odd Greater Black-backed, Caspian and Yellow-legged Gull.

From mid-June, numbers of adult, post-breeding Black-headed Gulls started to build up on the river Don, with the first juvenile noted on 30 June and three to four juveniles present over the next few days.


Juvenile Black-headed Gull. Photo by Andy Deighton


The nearest known large Black-headed Gull colony is at Old Moor, about 14 km away, so any juveniles in Sheffield might not be expected to have travelled far from the breeding colony.

Checking the birds on 7 July, a colour marked Black-headed Gull was of interest, wearing colour ring white T25T. After reporting this via the BTO Euring website, it was a surprise to find this bird had been ringed as a chick in Poland, on 6 June, and was still present at that location on 28 June. It was then with us just nine days later having travelled a massive 1,070 km journey within approximately six weeks of hatching.

The bird wasn’t seen subsequently so was presumably still on the move.

24 July 2017

From the land of ice and Blackcaps

For Hugh Insley, ringing at this time of year means, amongst many other things, 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?