Food!

I have a hanging feeder in a very large shrub.  I mix special food using oats, sultanas, melted  margarine and sunflower hearts.  Every time I go to top it up this little Robin appears from nowhere. He hops up and down impatiently while I top up peanuts in other feeders, and then zooms in the minute I put oat this oat mix.  He (or she) is close enough for me to touch.  The bird flies off quickly with a beak full, (and returns quickly for more) so must be feeding young somewhere.  I always wonder how he KNOWS when I appear, as I don't stick to exactly the same time each day.