In the US you own the "work" as soon as you create it too. But you might be called on to prove it, either if you try to make money from it or if someone else claims copyright to all or part of your "work" (e.g., a tune).   

There used to be a similar organization called "Song Bank" or something like that, which would do the same thing in the US, 999.   Still, if you've registered your copyright with the Library Of Congress and have the documentation thereof, you could probably avoid having to deal with courts.