Hi - this morning my husband found what we think is a mute swan egg on our front walk. We live in Northern NJ on a small lake with a pair of swans. The egg is approx. 3-4" long and 2 - 2.5" wide. and is off-white with brownish markings (could be dirt?). He brought it inside and put it in a box for now. Is there anything that can be done or anyone we should call? Thanks, Lucinda