Birding dilemma

This week the first easterly winds of the autumn brought a steady stream of migrating birds to the coast where I live. Work commitments meant that I was unable to get out to see any of them. Today though my son Will and I set off full of hope. But the winds had turned to the west and the area was an ornithological desert. At last, in the fading light, our patience seemed to have been rewarded. On the cliff below us we heard the chipping call of a warbler. We could see the bush the sound was coming from about 30m below us. But we couldn't see the bird. It called away for perhaps five minutes and for the whole time we stared at the bush. Then in a flash it flitted out and made a dash to a second bush perhaps 10m along the cliff. Neither of us got our binoculars onto it as it flew but we both got to it just as it reached cover. At that exact second it became a blur of brown and white and all we saw was the yellow legs of a female Sparrowhawk that must have been waiting just as patiently as us on the cliff face below us. The Sparrowhawk grabbed it's prey and effortlessly glided away from us. So here is my dilemma. Do I feel robbed of the chance to identify my mystery warbler, or should I revel in the excitement of seeing such a fantastic piece of behaviour? On reflection I think I'm warming to the latter.

Tongue spots

 

How old is this bird?

Recently I was catching birds to fit them with rings (bands) as part of my activities as a British Trust For Ornithology (BTO) ringer. Specifically I was catching birds at Tophill Low Nature Reserve as past of the BTO Constant Effort Site  scheme (CES - more about that another day). As part of the activity we need to know the age of the bird we catch so that we can find out something about annual breeding success. So how old is the Reed Warbler in the picture?

 

Note the two black spots at the rear of the tongue

 

 

Well I know for a fact that on the day we caught it (back in August) it was only a few weeks old. And I know that because when it opened its beak I could see that it had two dark spots on its tongue. Lots of passerine chicks have tongue spots when they hatch that gradually fade as they age. I've always understood that the function of the spots is to make the gape of the chick more obvious to parent birds at feeding time - sort of like landing lights on a runway!