I didn't get a picture, because my camera batteries were dead - and then I completely forgot. I went looking this morning and now can't find the evidence - not surprising, as there are lots of hungry critters around. I know I should have kept it in the freezer for a day or two - but it was already ant-ridden when I looked at it and realized what it was.

Hilo, that was a good call, and I almost thought you were right. But the blackbird hasn't the yellow spots and there's the stripy breast as well.

I remember seeing some foriegn lark in a birdbook once that looked like a WTS, but I haven't had any luck searching larks.

I suspect it was just an abnormal sparrow - birds must sometimes be affected with giantism, like other animals, surely?