24 July 2015

Found a ringed bird? You are not alone.

With around one million birds ringed every year it is not surprising that we get quite a few phone calls and lots of emails to the ringing team from non-ringers reporting a ringed bird. We get back to each one a few days later with a report on where and when the bird was ringed, and at the same time let the ringer know that one of 'their' birds has been found.

When you add this to all of the recaptures of ringed birds by our ringers through general ringing, especially structured ringing like Constant Effort Sites and Retrapping Adults for Survival, the value of these reports to conservation is huge. There are many aspects of a bird's life that can be investigated by BTO scientists and academics, particularly when results from other BTO surveys, such as the Nest Record Scheme and BBS, are included in the dataset.

Great example of part of a Dunnock nest record by Christopher Rowe

Most of the non-ringers that report ringed birds just get information on the bird they found and are unaware of the magnitude of records that we process. I have looked into the 40,394 reports that have been sent to us so far this summer (since 29 March 2015) from ringers and non-ringers.

Below is a chart showing the percentage of each species that were found by non-ringers and caught by ringers. Blue and Great Tit are of course the top two, followed by other garden birds. Starling is unusually high due to some great Starling colour ringing projects operating from Essex to Montrose. We have had singles of some unusual species so far this summer including Icterine Warbler, Capercaillie, Ruddy Duck and Great Bustard but these are few and far between.

Finding reports sent in to the BTO so far this summer from ringers and non-ringers. Click chart to enlarge.

The chart below is purely those reported by non-ringers. Considering the recent declines in House Sparrow and Starlings, the reports of them are quite high but this is due to the increased conservation effort and colour ringing projects occurring on these species. Fifteen percent for Black-headed Gull isn't surprising for us as a large percentage of the Recoveries Officers' work is processing colour ring sightings of these birds moving between countries and within our country. There is also a large number of people devoted to gulls and ring reading.

Finding reports from this summer from non-ringers only

Our valued BTO ringers not only ring large numbers of birds, to increase our understanding of our bird populations, but they also recapture large numbers of birds that are already ringed. This accounted for 81% of all the birds 'encountered' and reported since 29 March. These are reported to us using a dedicated computer program and thankfully need less processing than non-ringer reports. Out of the non-ringers reports 78% are colour ring sightings - see below for the top 10 circumstances of the report. Discerning the cause of death can be difficult and these records are represented by the red slice on the chart below.

The top 10 circumstances that led to us getting a report this summer.

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