>>26770059>>26769889OP here, yeah, I agree with you guys. Especially with Yungoos being found on Route 1, I'd agree that it's a regional rodent.
But I have an alternate theory now. Maybe there are two regional rodents? This one, and the one that Yungoos was brought into maintain.
And we know the "certain other pokemon" is a rodent because we know Mongooses were brought to Hawaii to deal with rats, specifically, the black rat (pictured).