Yes it is, they also protect the nest from intruders. Mt.Tortoise nesting is more like the America Alligator than other tortoises. It's a long process of "backsweeping". They move backwards sweeping ground matter to the nest mound where she then diggs a hole in it to deposit the eggs. Then like the Alligator stands guard.(even though I take the eggs out). I've tryed putting some pipping eggs in the nest to see it they return to protect them, but they dont. Some are hatching NOW ! VM