Richard,

I think that your idea of the metal snare might be the best answer. I do not
know if you have cruised along the coast of Maine before but we can have
weeks of fog and you and your drum could be in 100% humidity for your whole
trip. The idea of a desiccant in a bag may work but if you have an option
why risk a valuable instrument?

Ansley Sawyer
SV Pacem