my boyfriend and I have a two year old african desert tortoise. we put him outside when it is warm and some times he will go missing for 2 to 3 days. we search and search and can't find him. where can he go? the gate is shut closed and the yard is not that big. can he burrow himself in the dirt so good that he can't be found? is it possible he could get stuck in the ground? i am so worried that some type of animal came into the yard and snatched him. do you have an suggestions? thank you.