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).

08 April 2016

First British-ringed Stonechat for Norway - rubicolus?

John Secker from Thetford Forest Ringing Group writes:

Since 2003, Stonechat breeding in the Forestry Commission’s Thetford forest on the Norfolk/Suffolk border have been surveyed. The population has been as high as 56 pairs (2008, after a run of mild winters), and down to just four pairs (2014 after a run of relatively cold winters). In 2006 a project to find nests, and colour-ring both chicks and adults was begun by Thetford Forest Ringing Group.  In total, 750 birds have since been fitted with combinations of three colour rings and a metal BTO ring; 673 have been nestlings, 37 adults and 20 fledglings.

There have been many re-sightings within the forest area and Breckland generally, but also eight from further afield, mostly within East Anglia. The furthest travelled bird being seen near Chingford, East London. But certainly, nothing prepared us for what was to come.

Stonechat - photo taken by Odd Kindburg in Norway

On 27 March 2016 two birders (Odd Kindberg and Fredrik Tjessem) photographed, and reported to the BTO, a colour-ringed female Stonechat, near Tangvall, Sogne, in Southern Norway. The bird had a pink ring above a pale blue on the left leg and metal above pale blue on the right. The combination certainly matched one used in Thetford Forest but all the same, although we could not find any other studies that might have used this combination, we had to wonder whether or not someone closer to Norway may have colour ringing this bird. But from what we could make out from the photos, the metal ring did look tantalisingly like a BTO ring. We got back in touch with the photographers and in no time at all Odd was back on the case and we soon received a new batch of excellent photographs that enabled the entire ring number to be pieced together and therefore rule out any confusion with other studies – BINGO!.

Records showed that this bird was from a nest found by Gavin Chambers in May 2015 near Grimes Graves in Thetford Forest, Norfolk. The chicks were ringed by Ron Hoblyn and me, and the nest fledged successfully. Tangvall is approximately 750 kms North-east of Grimes Graves.
None of the other birds recorded away from Breckland has moved in a north-east or easterly direction.

This is the first ever British-ringed Stonechat to have been reported from Norway. Stonechat was not found breeding in Norway until the 1970’s, when a population of the British race, Saxicola rubicola hibernans established itself. It was speculated that those birds were of Scottish origin, Scotland being the closest part of Britain to southern Norway. But maybe this new record suggests an alternative.

Stonechat showing the three coloured rings - photo by Odd Kindburg

It is possible that the bird became caught up in one of the powerful south-westerly storms that have swept Britain this winter, but perhaps more likely that it made the shorter crossing to the Netherlands and then moved north into Norway. Either way it is a fantastic record and demonstrates the possible rewards to be had from colour-ringing birds.

It will be interesting to find out whether or not this individual stays to breed in Norway.