Hatch no longer eat and excrete coal or burrow

My Hatchs one day all just diapered. Loaded the game after one hotfix and poof, no more Hatches throughout my entire map now. Reloading old save didnt seem to fix this problem, could be part of the same bug.

Well, hatches have a material hardness limit, so they need dirt, sand, algae, etc anything with hardness 25 or less I think.

 

I also noticed my hatches disappeared. I had 4 in one area with plenty for them to eat, and then they were just gone.