In near perfect weather things got off again to a good start and kept going until around 9 am when we finished. The combined total was 118 new birds with another 38 Blackcaps,24 Chiffchaffs, 6 Sedge warbler, 4 Reed warbler, 2 Garden warbler and 1 Lesser Whitethroat. It's noticeable--but expected, that the reed and 'sedgies' are dropping off as they have almost all set off on their long migration south. Even after all these years we've been ringing, Pete and I still marvel at the incredible feats of endurance and navigation these tiny sprites undergo--brilliant!
As the mornings at this time of year tend to be a bit cooler, it gives u the opportunity of ringing 'hirundines'. This is the collective group comprising Swallow, House and Sand Martins in the UK. The cool air keeps their flying insect food low which in turn means the hirundines need to fly low in order to feed--thus bringing them within catching range. This morning saw a squadron of Sand Martins whizzing round the nets and resulted in us ringing 22 of these little beauties. Over the years we have ringed thousands of sand martins-which are easy to age because juveniles have pale edges to many of the upper body feathers as you can see in the three pictures below--all of which are juvenile birds. But look a bit closer and you will see subtle differences in the colour of these edgings:-
This bird had pale buff edges
These edges are predominantly white
And these are mixed white and buff.
We suppose that somewhere there is an explanation in the text books but we've never seen one. I have a hunch that the edges start off white and that in some cases perhaps the colour of the sand (in which this species digs nest burrows) may stain the edges buff? Doesn't really explain the mixed bag though..........!!??
Since we had our session today--THERE IS NO SESSION ON WEDNESDAY 4th
Next session is planned for Saturday 7th.
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