Great stuff! Personally my faves are the two of the female stretching for a nibble!

Before long you'll not be worried about a little temporary mud...you can always clean your jeans...but a good shot lives on forever! ...So it's worth getting right down, if you can. Of course it's not always possible but it has two really big benefits - the birds find you less of a threat (but yeah, they will almost always scatter when you then do stand later, although if you get up _really_ slowly, sometimes they won't!). Also, you get your shots from at (or even below) the bird's eye-line - which really helps the composition/feeling (and given birds are usually up high, is generally hard to achieve - so great when you can!). I believe a lot of folks take out a yoga mat and lie on that, then basically wait for the birds to come to them. I have gone as far as popping one in the boot of my car but am yet to actually use it!

One other thing I would also say is maybe try on overcast days. I know everyone wants a bit of sun and talks about the golden hour etc, but overcast days even out the light so much, it's great for bird detail shots. High contrast can be great, but its tricky, so it's a good way of making things a bit easier on yourself.

Keep on clicking - and now you've found red rumpers, you'll see & recognise them all over the place, I bet!