Feeding the birds

The blackbirds seem happier eating the apples wherever they are, whereas the Fieldfare that has taken up winter residence - assuming it is the same bird that keeps coming back - much prefers eating them on the ground, even if it means digging around in the snow. If it is the same Fieldfare all the time, I wonder if it is in fact the same bird that was here last winter and if so where it has been for the summer...