JRPass

Hi again Ruby!

I'm afraid the Niigata > Ryotsu line is run by a private (non-JR) company called Sado Kisen, so you will not be able to use the Japan Rail Pass for this bit of your journey. Here is the schedule of the ferrys from Niigata to Ryotsu for April (their is enough english to make them understandable).

Regarding reservations, it does look like you'll have to book your ticket advance. Here's a google translation of information for first time ferry travellers on the Sado Kisen Ferry, and a list of reservation telephone numbers you may find useful.

Online reservations can be done here, but again, only in Japanese, and google translate won't work in order processing pages...

Your best option is to call the Reservation Service Center on 025-245-6211 between 8:30-17:00 Japan time, or the Tokyo office (where they'll have more english speakers) on 03-5390-0550 and arrange your reservation over the phone.

For reservations (both telephone and internet), you don't have to pay immediately, but instead pay at the ferry gate when you go to pick your tickets up, so there's no harm in giving them a call - think of it as practice for your trip :) !

Hope this helps!