Register kayak?

I have a trolling motor mounted on my hobie and would like to know if I needed to register my kayak along with a CCF# in order to use it. I've used it for 2 years now without any issues but recently took it out to a lake and a fellow kayaker came by and looked at my kayak asking for a CF#. I did some searching online and it says any motorized watercraft needs to be registered. Just wanted to double check with you guys here before doing so.

Thanks in advance