What can you use on eggs to mark them that the mother cant take odd while she is sitting..she kept trying steal eggs and we need to be able to tell which were her original clutch...we used pencil but it wore off ..thanks..
I use a Sharpie marker with no problems. Also consider marking the eggs at the ends instead of the sides. The ends get much less rubbing against the hen than the ends do. I simply place an "X" on each end and it lasts through to hatch every time.
I used a sharpie for 5 years and never had it affect my hatch rates. I still use a sharpie if I am letting a broodie sit on eggs. A pencil does not work as she will rub off the marking. When I set eggs in my incubators I use a pencil, but I am putting eggs in an incubator from 6 different breeding pens and am putting on the eggs, the hen that laid them, the pen they are out of, the date they are collected and the date they are set to hatch. That would be alot if using a sharpie. The most I wrote on eggs with a sharpie was and X or the date.