Monday, 15 April 2019

Rapid Goldfinch movement.

Earlier this month, in a blog post titled 'fatties', I mentioned catching some Goldfinches at Crawford that had significant fat deposits. I went on to say that they were migrants that would be heading much further north to breed and presumably to somewhere in Scotland or Northern Ireland. Since then I have caught other Goldfinches at Crawford with varying amounts of fat and I recently received a recovery report for one of them. Goldfinch ACF5670 was ringed at Crawford on 07/04/2019 at 09:20 and was subsequently caught by a ringer in Leswalt, Stranraer, Dumfries and Galloway just 2 days later on 09/04/2019 at 14:00.

It was a small female that wasn't particularly fat and weighed 15.2g at the time it was ringed and subsequently weighed 13.9g when it was recaptured at Leswalt. The weight difference of 1.3g gives some indication of how much fat it used to make the journey. The straight line distance from Crawford to Leswalt is 219 km but most of that direct route is over the sea, as can be seen from the map. Goldfinches generally avoid making long sea crossings and migrate overland as much as possible so it is unlikely to have taken the shortest direct route. If this bird took an overland route to Leswalt it will have travelled around 300km and possibly quite a bit further than that if it followed the convoluted coast of Northwest England and Southwest Scotland, even with a bit of a shortcut across an estuary here and there. There is also the possibility that it took a relatively direct route via the Isle of Man and there have been some recoveries that make that a realistic option but it still involves quite long sea crossings. One thing is sure it is an interesting movement for its speed whatever route was actually taken.

Goldfinch (Carduelis carduelis) Ring no: ACF5670
First-year Female   07-04-2019  Crawford, near Up Holland, Lancashire, England
Caught by ringer    09-04-2019   Leswalt, Stranraer, Dumfries and Galloway, Scotland
Duration: 2 days Distance: 219 km Direction: 317deg (NW)

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