Tuesday, 8 December 2015

Goldcrest Recoveries

It was a fantastic autumn for Goldcrests at Billinge and large numbers were ringed even before the big influx of continental birds that came in October. The ringing site itself doesn't hold any breeding pairs or wintering birds so all the Goldcrests caught are effectively passage migrants. A few pairs breed nearby and the first birds of the autumn were dispersing juveniles with 8 being ringed in July followed by another 16 in August. Autumn migration proper got underway in September and 258 were ringed that month. Numbers were boosted in October when some of the continental birds worked their way across the country from the east coast and the month ended with another 336 having been ringed. Reasonable numbers were still moving through in November but only 75 were caught as poor weather frequently hampered ringing.

In addition to the 693 birds ringed a total of 7 controls (birds ringed elsewhere) were caught and I have now received details for 6 of these birds. The first of the controls was a short distance movement of 3 km, a bird ringed at Kings Moss on 12/10/14 and controlled at Billinge on 07/09/15 and isn't mapped. The other controls had moved a good deal further as can be seen from their details and the map below. The two red pins mark the ringing sites of birds that are most likely to be from the British breeding population whilst the 3 yellow pins mark the ringing sites of continental birds that were caught during the large influx along the east coast. The black pin marks the ringing site at Billinge.

HKD161 ringed 05/04/15 Bardsey Island, Gwynedd - controlled Billinge 25/09/15
EBK202 ringed 11/10/13 Greystoke Forest, Cumbria - controlled Billinge 28/10/15
HVB825 ringed 16/10/15 Skelton Castle, Redcar & Cleveland - controlled Billinge 28/10/15
HHJ840 ringed 17/10/15 The Headland, Hartlepool - controlled Billinge 28/10/15
JDP045 ringed 11/10/15 Kilnsea, East Riding of Yorkshire - controlled Billinge 31/10/15

Control Goldcrest HHJ840 had been ringed 11 days earlier in Hartlepool.

It is early days yet but there have been two recoveries of Goldcrests that were ringed at Billinge this autumn and both were found freshly dead having flown into windows. JBX684 was ringed on 13/09/15 and was possibly still migrating when it was recovered in Long Itchington, Warwickshire on 19/10/15. 

The second recovery is of bird that was ringed quite recently and it was recovered surprisingly quickly. JJH263 was ringed at Billinge on 22/11/15 and was found dead at Lathom, Lancashire the following day having moved 11 km NW. This is a quick recovery and although it hadn't travelled far it shows that this bird still hadn't found a suitable unoccupied site where it could settle down for the winter. Goldcrests' food requirements of insects and insect eggs in particular means they can't winter at high density, even in good habitats, so this must play a big part in their movements and winter distribution. I did notice some noisy and aggressive behaviour between 3 Goldcrests near my garden recently. This appeared to be territorial in nature and such behaviour presumably plays a part in spreading birds out.

Details of the outstanding control and any further recoveries will be posted in due course..

Goldcrest HJV774 controlled at Billinge 20/10/15.
The ringing details of this bird have yet to be received but it certainly looks like a continental bird so it may also have been ringed on the east coast ??

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