Monday, December 19, 2011

I (Giselle) have been cracking on with the Ringing Recoveries and Controls section of the report.  Every year the island receives reports from the BTO of birds we've ringed that have been recovered elsewhere in the world. Finding conditions of these birds vary. Many are reported dead and a good number are also re-trapped by other ringers elsewhere. Ring numbers are also read in the field on live birds. This is trickier because the bird has to hang around long enough to get photographs or to be able to see all angles of the ring. However it is a surprisingly popular past time to hang around tips reading gulls rings. Gulls like tips, and are likely to stick around long enough for a reliable ring number to be read.

A Lesser Black-backed Gull that was ringed as a chick on Bardsey in 1991 was observed at a landfill site in Deux-Sevres, France in November 2010. This was possibly the first resighting of this bird for 7089 days. (c) Richard Brown

Perhaps the most exciting ringing recoveries come from species that travel large distances. For instance, a Manx Shearwater ringed as an adult in April 2009 was found dead in Rio Grande do Sul, Brazil in November the following year.  That's a one-way trip of 7663 km, although as the bird was found fresh-dead we can assume it travelled to Brazil in the winter of 2009, returning to Bardsey again in April 2010 to breed before heading back to Brazil where it died. So that's 30,652 km that we know about, but as it was ringed as an adult, it's impossible to know how many hundreds of thousands of kilometres this bird travelled in its lifetime.

 Redwings are winter visitors to Bardsey and a slack handful are ringed on the island every year. A juvenile Redwing was ringed on Bardsey on the 27th October 2009 on it's first winter migration. It will have then made it back to Scandinavia for the subsequent breeding season but was shot in Norway on the 9th of October 2010 as it headed south again for its second winter. It is legal to hunt Redwings in Norway between the 10th of August and the 23rd of December, this being the peak migration period for this species. As awful as it seems, many recoveries of birds are those that have been hunted. Indeed much of the information we have on wintering areas and migration routes of British breeding warblers come from hunted birds in Southern Europe. (c) Richard Brown

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