Or rats: they see periodic population explosions as bamboo comes into seed. So could Man exploit animals that eat rats? Like owls or cats or something?
As verminators, certainly but do you mean as food? It would be more efficient to just eat the rats (which many people have done in the past and continue to do today).
Actually, there's evidence for habitation in South America, by an entirely different group, dating to at least 40KYA, & maybe as much as 60K. (I suspect they were Proto-Polyneisans: recall, sea levels were lower then, so there'd be more Pacific islands.)
Eh...there probably were people in the Americas before the Clovis hunters, but we don't have a lot of proof. I also doubt that if there were people in the Americas at this time that they were Proto-Polynesians, because if they had crossed the Pacific they would have colonized the islands which were uninhabited before the Polynesian expansion.