Great stuff is a spray foam insulation it will alway expand as it sets that is what it does. If you sand it down wear a respirator or a mask you don't want to breath it in and do outside.
that sucks man sorry to hear. next time try a quick google with in the first couple selctions of typing in reptile city. Is poor reviews. hope the female survives.
There has been a big push the last ten years to help turtles. In the outer banks they set up boundaries so that you can trample or accidentally dig up turtle nest. I always love when people give back. I'm hoping my work will slow down at some point so I can volunteer agai.
Great job do you have pictures as you built this I am interested to see your process. What you started with to what it is now. I think it is the carpenter in me. Either way you have a artistic mind for how you set that up