Can I drive the Animal Population of Skyrim into Extinction?
Solution 1:
I just fast traveled to
Secunda's Kiss
to check out whether giants respawn. I killed the giants there on my first trip from Riverwood to Whiterun by abusing the pathing.
The giants were back. They do respawn.
SevenSidedDie points to the answer for animals in his comment: yes, they also respawn.
I also recently revisited
Shearpoint
and the dragon there had respawned, so even the static dragons respawn.