Are Marans eggs more difficult to hatch? I can't think of any reason they would be. I've just tried to incubate a dozen black copper Marans eggs i purchased, no shipping involved. 8/12 were fertile and developed full term, only two tried to hatch and both had curled up legs and had to be culled. The dozen Ameraucana eggs of my own I put in at the same time had 7 fertile, all hatched and are perfect. I am using a brand new sportsman. Spot on electronic controls. Just trying to figure out what happenef as the bought eggs were not shipped. It's my third hatch in the new incubator, and this problem did not occur with the other eggs.