Question: when to move salamander

Hi all! I posted a few weeks ago with my tiger salamander larvae asking if they were actually axolotls or tigers and got some wonderful responses about them being tigers. Well, Mikey, the middle one has morphed and is now sticking his head out of the water quite a bit. Spike has begun the process and Cougar hasn't shown any signs yet. I have a large rock accessible to them that can be climbed on to get out of the water but Mike doesn't seem to want to use it yet. At what point do I know to take them out of the mostly aquatic environment and set them up in the mostly "land" based environment? I am planning to move Mike when I realize it is time and set up a small "pool" for him to use in his new home.

Any help anyone can give would be greatly appreciated as I am obviously new to this and went in thinking I would have animals that were aquatic. They are such cute little guys that I want to make sure we do the right thing for them. My sister had 6 and apparently one of her very small ones morphed and perhaps drowned because Pitree didn't make it. I don't want that to happen to my 3 guys!

Thanks in advance for your assistance!

Rocks don't make appropriate land for morphing tiger salamanders. They're bare and open, where as tiger salamanders are fossorial (burrowers)

Once the gill stubs are absorbed, they can be moved to a terrestrial setup.

Thank you, I'll get him switched over to land tomorrow.

I think it'll be much happier.