Kayak to log vessel time towards OUPV license?

Is time in a kayak is allowable in building time towards getting a captain's license? I've been looking through the code of federal regulations (CFR) title 46, looking for an answer. So far, no luck.

Textual citations appreciated. I wouldn't be building all the time in kayak, but it is a relatively thrifty way to float and fish. I think if the kayak had a sail, maybe logging time time would be allowed. What about time paddling?

Thanks in advance.
Brent
Folbot Greenland II