As nest building begins robins, sparrows, blackbirds and other garden birds fly back and forth with twigs and other plant debris.
You can help them out by tying up bunches of tiny twigs, dried moss, and other stringy vegetable matter near your feeders. Tiny warblers such as chiffchaffs return from Africa, having made the perilous journey across Europe. They are difficult to spot, although you might hear them singing in hedgerows and thickets.
Click here for more information.: Gardening in March | Birds & Wildlife in March – The RSPB