Is it on the same planet? Yes. No one's arguing that.

As someone who is a geologist who studies continents, I am telling you, specifically, in science, no one calls common loons North American. If you want to be "specific" like you said, then you shouldn't either. They're not the same thing.

If you're saying "North America" you're referring to the tectonic grouping of the Americas, which includes things from North America to Central America to South America.