It was a GRAND session this morning!!

Indeed it was! A few much better days of clear weather promoting migration, and a perfect morning for ringing resulted in a total of 97 new birds ringed with the vast majority being migrant warblers. Migration is well under way now and it really showed in the catch.
Sedge warblers again dominated with 37,followed by reed warblers 17, blackcaps 14, chiffchaffs 8, willow warblers 7, garden warbler and lesser whitethroat 2 each and 1 common whitethroat. We also ringed our first Marsh tit of the season. I've called it a GRAND session because today we passed the 1000 birds ringed at Belvide since 1st July this year!!
There were some quite interesting birds for our trainees to learn from this morning:-
When blackcaps leave the nest they all have brown caps. Over the following weeks, they moult out those 'baby' feathers and grow in black feathers if male and subtly different coloured brown feathers if female.

 The bird on the left is a newly fledged bird with 'fluffy' cap feathers and the bird on the right is a slightly older female which has moulted its fluffy feathers and grown in the better quality slightly browner feathers which it will carry for the whole of next year.
People often ask how you tell a lesser whitethroat from a common whitethroat. I think the following picture says it all. The lesser is on the left and is essentially a grey and white bird while the chestnut feathers on the wing of the bird on the left makes it a common whitethroat.

One of the things ringers need to get their eye in for is spotting the difference between old, worn adult feathers which birds typically have at this time of year ( having had these feathers for almost a year including the rigours of breeding), and the fresh new feathers of newly fledged juvenile birds. These are often also of slightly different colour shades.
This is shown in the next two pictures of  adult and a juvenile reed warblers. In the first picture the adult is on the left.

You can see how the juveniles colour is richer brown and the feathers are smooth and in good condition. The adult feathers are greyer, washed out and much tattier looking. This is even more evident on their tails:-

The adult tail is the upper one--no comments needed really.
Finally, willow warblers at this time of year can be tricky to age--but this bird showed two features which made it relatively easy to age as an adult:-

First, the belly feathers are almost completely white--in a juvenile this area is almost completely yellow:-

Second, the tail feathers are broad without sharp points and with no chips out of the tips which often happens with young birds in the nest.
Finally Marsh and Willow tits are always a challenge in the hand--probably more so than in the field where the call is diagnostic.

This bird looks a bit scruffy because it's a juvenile in post fledging moult, but the important features can be seen. It does not show a pale panel on the secondary feathers in the middle of the wing; the cap is more restricted at the rear of the head than in willow, and the cutting edge to the upper mandible is white expanding to a broader patch where the bill meets the feathers. It's also overall a tad greyer and colder coloured overall than a willow