Rich there is a small inexpensive battery operated air dehydrator you can get plus several bowls or disposable pie tins of kitty litter will help too....the dehydrators are availiable at rv stores...I will be looking at them this year as my brother uses them for his airplane.

Good point Rob.  Although I never had that problem with my aluminum boat, it is a fairly common issue.

When I stored my tin boat outside, my problem was moisture in the storage compartments.  Despite using a waterproof tarp, my compartments were mold factories.  This was because my compartments were not waterproof at all.

To remedy this, I used small blocks of wood to prop open all the compartments during storage.  This virually eliminated the problem.  Of course, that leaves your stuff vulnerable to theives, so I really, REALLY bundled up the boat in that tarp!  I used rope and multiple bungee cords.  It was the equivalent of a combination lock because you had to figure out how to undo everything.

Of course, you need prop up the tarp accordingly so water/snow/ice doesn't accumulate anywhere.

I heard that peppermint oil works well for rodents.

Oh....and Rich.....those are not Almond Roca's in that kitty litter!

Driz-air makes dehumidifiers that are not powered, you just pour in a bag of crystals and then empty out the water once in a while.

Try Home Depot...

Dieharders don't shrink-wrap their boats for the winter. Unless I guess you live somewhere where everything freezes over. Then you tow it onto the frozen lake, drill a hole, and fish through the ice from your boat....

Guys... I think Rich wants answers, not ridicule.

Rich, personally I haven't shrinkwrapped, and don't know anybody who does.  But, I've heard of people doing it in harsh climates.