Beautiful portraits of tree sparrow - really quite unfair that you make drawings like this (also, are you left-handed by any chance, Alan?). The magpie is a dead cert for a finished painting - if I were you, I'd get out a piece of board or tinted card and make a colour sketch now, whilst the observation and this drawing are still so fresh in the mind. You could almost simply add body colour to this one - it would soon be a 'finished' piece.
Another excellent post.
Ps - looks like the new optics have come up trumps - always a little bit inspiring to use new stuff, isn't it.