Recreational Skipper’s Licence

Hey there!
My partner and I will be on Lake Nojiri (Nagano) for a few days, and I saw that you can rent a small boat (2 people) for fishing and going around the lake.

I understand that locals often come and rent a boat, however they need their boat licence (recreational Skipper’s Licence) to get one.

I have an Australian Skipper’s ticket, and was wondering if it was possible to use it in Japan, or have some sort of transfer done?

Or, perhaps I misunderstood and I don’t need a licence. Thanks in advance!