If you are going to have trouble with birds, then invest in some bird netting. You will also need some twigs to hold the netting off the ground, 4" at least, and pegged down round the edges.
Obviously you cannot walk on this area, and you wouldn't want to , until the grass has grown to a reasonable length. When you cut it, I would recommend you do so with hand shears, just snipping the tops to start with, leaving the grass quite long until it is well established.
I've got some grass seed which has been treated to discourage the birds. The trouble is, when one bird has tried it and found it distasteful, it fails to tell t'others. :o