12 April 2016

Do Blue Tits move very far?... Generally no.

Ian and Sally Hunter from the Sandwich Bay Bird Observatory write:

Small groups of Blue or Great Tits, with the occasional Coal Tit, moving southwards along the seafront are not uncommon during visible migration observation at Sandwich Bay.

Despite 10,381 Blue Tits having being ringed by the observatory, we have not really discovered much about their movements. Until 23rd March 2016 the observatory only had one foreign control (ringed abroad), from the Netherlands, and one foreign recovery (found abroad), to the Pas de Calais region of France. Other movements were usually within Kent (19 birds), mostly to/from coastal sites, with six to/from other southern counties. The BTO ringing scheme as a whole has only had an extremely small number crossing the channel.

Blue Tit recoveries involving Britain & Ireland
Colour of location: Ringed in Britain & Ireland, Found Here; Ringed Here, Found in Britain & Ireland
So when a Blue Tit wearing a Lithuanian ring was captured, there was plenty of excitement. The bird was noticeably brighter blue than local birds. Its wing was a big 70 mm and it weighed 11 grams (average for British Blue Tit is 63mm wing and 10 grams). Interestingly the previous day a white headed northern race Long-tailed Tit had been observed and two days later a continental Coal Tit was ringed.


Lithuanian Blue Tit. Photo by Becky Johnson
The map below shows just how far this bird has travelled from Ventes Ragas, Silute distr. It was ringed as an adult Blue Tit at 13:00 on 15 Sept 2015 (nearly 1,400 km in about 6 months).


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