Or is that a bad idea?

I'd do it....

also add on... how about while on shore?

Yes u can use them anywhere. All about proper placement.

Would I even be able to feel it?

I'm thinking duct tape the bottle to the vertical post of my spider rig set? I don't know though. Doesn't seem very efficient.

Used one while fishing tournaments to keep hands warm. Just hope the boat doesn't have a gas leak.

This is funny. Is the heater lit or is it spewing gas?

Dumb questions get dumb answers.

in alaska my guide on a "fly in lake" one year ....
fired up a cook stove and filleted one of our right out of the water sockeye salmon .....
on a 20 foot john boat !
with 4 of us in it !
didnt bother me at all .....and the salmon was ....mmmmmm yummy
so why not a propane heater ....is my thoughts
and no i still cant figure out how they got them john boats in that lake .....man was it remote ....

My dad used a small galvanized bucket and put about 3 inches of sand in the bottom. Then add regular BBQ charcoal and light them up while on shore. Those coals stayed hot for hours and would keep your hands warm. Never had to worry about a open flame in the boat and could cook hotdogs at the sametime.

Reggie

I remember as a kid, my dad had a catalytic heater fueled with Coleman fuel when we fished Lake Meredith in the Winter. I seem to remember we stayed pretty warm.

Mr. Heater 'Buddy' ,or the Mr. Heater 'Big Buddy'. They are both indoor safe, auto shut off if tipped over, built in Igniter, Buddy approx. 9K BTUs, Big Buddy 4K, 9K, up to 18 K BTUs depending on settings. Buddy uses 1, 0ne pound bottle of propane bottle, Big Buddy uses 2, one pound bottles of propane. Northern Tool has the best prices on um. I've been considering buying one of um, for my boat.

They go thru a bottle fast! So get em' cheap! Never used on the boat. Just hunting.

A long, long time ago in a galaxy far away, I owned a pontoon boat and we used a Coleman catalytic heater on it while sandy fishin. Worked great, kept us from freezin an had no problems with it.
Go for it, beats the alternative!

Tank Top Heater with 20 lb. tank in a tank base is the most economical. One pound bottles get expensive !