The rules mention that to follow tracks, you need to find them. It is also mentioned that it can take up to an hour outdoors to find tracks you have lost - all under tracking, which is Wisdom (Survival).
The way I read it would be to use Survival no matter the situation (for both finding and following) but I read some people would use perception or investigation to find the tracks. When looking at the table for Sylvan random encounter in DMG p. 87, in one entry it uses Wisdom (Survival) to both find and follow the tracks.
Also, I see a problem using other skills to find the tracks for a Ranger character because Ranger favored enemy feature states you have advantage on Wisdom (Survival) to track your favored enemy. Then it would be very strange for the Ranger not being able to find tracks he could easily follow due to his advantage on a check. And what if the Ranger for some reason is not proficient in perception would never be able to find tracks so not able to follow any?
So, the question is easy but I fear the answer is not, as I was not able to find a straight answer to it.
I want to make sure that any character who want to become a good tracker (either through ranger or rogue sub-class) can do so. I feel that having to be good at 2 or 3 skills to accomplish one thing (i.e. tracking) is not the common usage of skills in 5e.