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Sunday 31 July 2022

They are on the move already!!

 As I write this, July has not come to an end, but we are seeing lots of evidence of birds starting their southward migration. This is often preceded by a bit of general wandering --believed to be a means of searching for suitable nesting areas when they return next year.

Yesterday we were very pleasantly surprised to catch a very young juvenile Redstart:-

You can tell it's a REdstart by the superbly russet coloured tail--but the body has not yet developed any of the typical Redstart colours. This is because it is a recently fledged bird showing the speckled appearance just like the baby Robins I have shown you in previous notes. So, where did this bird originate--answer we don't know. Feasibly one could argue that it's probably from nearby breeding site--Cannock Chase or East Wales--but in truth we don't know. What is certain is that it's migration behaviour has started and it will be on it's way to sub Saharan Africa any day now.

We don't have Lesser Whitethroats breeding at Belvide, although they are in the lanes around the reserve. These are one of my favourite warblers and this picture shows off its pristine post fledging plumage....
When these birds leave the nest they have a rather poor quality plumage on the breast in particular. Shortly after fledging they replace these with the pure, dense, white plumage you see here. Fantastic little birds--and quite unusual in that rather than take a south/south west route to Africa; Lesser Whites, fly south east and cross the Med Sea towards Egypt.

Each month team member Sam trawls through the BTO records looking for records of birds that we have encountered. This month there was one in particular which was worthy of special mention--a bird  Reed Warblers originally ringed at Belvide....

Ring number Z203549 was ringed on 31st July 2015, and we recaught it on 2nd July this year--2527 days after originally being ringed. So this bird was at least 7 years old, meaning that it had successfully completed 7 migrations to and from Africa!! Just looking at the actual migration flights alone this would entail somewhere around 150,000 miles--assuming it flew in a straight line ( which they don't!!). When you add on the daily feeding , breeding, other flights this bird will have racked up an incredible mileage--even without an annual MOT test.......

Speaking of birds replacing their initial set of feathers after leaving the nest, Pat out at Siskin City, has been catching quite a few juvenile Siskins looking like this one....
You can quite clearly see the yellow chest feathers coming through to replace the fledgling white feathers, which will give these birds their characteristic bright yellow underside when they've completely grown through.

As I've said, migration is well under way, and we have ringed over 1,000 birds in July! Assuming things go according to plan, this should be at least repeated in August--more news soon.








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