"The squirrel hides its nuts."
Translation:Egernet gemmer sine nødder.
"Egernet skjuler sine nødder" is fine. I would like to add one thing though, i have no problem with animals hiding or "gemmer" something but "skjule" is perhaps better translated as "conceal", two words which to me imply a consciousness and awareness of the (bad) intentions of others.
In other words "Egernet skjuler sine nødder" could be used in a story about anthropomorphic animals but i would not recommend it in a nature documentary.
Gemmer is definetly the best translation but I don't see any reason why squirrels skjuler couldn't be a proper translation in the context. Personally I'm not too keen on how squirrel psychology works, but I don't see any reason why they wouldn't be able to tell, that someone was trying to get to their nuts.