We're stuck in 2016

Since the end of 2016, the Demography Team has been hard at work loading all the ringing data received from our ringers. Data are still coming in by the 'file load', but here is a sneak peek at a few highlights of 2016.

The big question is always, "how many birds were ringed in 2016?". I don't think we will reach a million birds ringed this year, possibly due to Blue and Great Tit not having a great year. We are currently on 990,808 birds ringed and there is a corresponding 281,880 records of birds already wearing rings (either caught again by ringers or found dead by anyone).

The graph below shows the 20 most ringed species in 2016. Despite them having a poor year, Blue Tit is still by far the most ringed species but perhaps more interestingly, Goldfinch is in second place. BirdTrends records show that Goldfinch numbers have increased substantially in recent years; however it is only the 10th most recaught species.




Top 20 species of birds ringed in 2016. Click to enlarge.

Unlike Willow Warbler, Chiffchaff has been doing very well recently, and as you can see from the graph, was the fourth most ringed bird in 2016. The preliminary results from the CES scheme show that Chiffchaff had the highest adult abundance in the history of the scheme last year. Unfortunately, productivity was significantly down in 2016 and the Nest Record Scheme results show that the mean laying date was eight days later than average. Chiffchaff that had originally been ringed in the Channel Islands, Germany, Spain, France, The Netherlands and Portugal were found in Britain and Ireland in 2016. All, apart from three birds were caught by our BTO ringers, one was found dead and two hit a window (one survived and one didn't).



A young Chiffchaff. Photo taken by Lee Barber

Coming in at number five of the most ringed bird for 2016 was Blackcap. This bird also had a high adult abundance and an even lower productivity than Chiffchaff  in the preliminary CES results. The North Wilts RG ringed an impressive 2,209 Blackcap in 2016, and their ringing session on 11 September, where they caught 257 Blackcap (most of which would have been on autumn passage), will always be remembered by the team on that day.

Male Blackcap. Photo taken by John Dunn.

Some of the more unusual recoveries we received in 2016 include a Blackcap which was found in a 'Horse water bucket', ringed by the West Wilts RG in 2011. We occasionally get birds being hit by vehicles, however I have never heard before of one which was 'trapped inside locked vehicle (entered through partly open window), fresh dead'. We also received a report of the fourth Slovenian ringed Blackcap found by a non-ringer. There are still a few records to be processed of BTO-ringed Blackcap that were found abroad and we look forward to processing those and letting the ringers know if it is one of theirs.

All of the recoveries of fresh dead birds and recaptures of live birds, feed into the longevity records for Britain and Ireland. It will be a little while until the 2016 records are added, but there are a couple of records that look to update the current longevities. The Bisham Barn Owl Group look to have just pipped the current record by a few days, originally set in 2012 (of 15 years 3 months). Click here for more information. The Mediterranean Gull record currently stand at 15 years 3 months as well, and Allan Hale has reported two colour ringed Med Gulls at Great Yarmouth beach, which were ringed just two days apart breaking the current record by over three months.

This post covers just covers the tip of a very big 'data' iceburg, so as we have more time to look into this data, we will undoubtably uncover more exciting information.