Get it off the boat, or fumigate the boat. Those things crawl into tiny spaces and can short electrical equipment. I had one short and destroy a circuit board in an aircon at home, cost $750 to replace. They are a potential fire risk.
Not sure if you have as many as we have in south Florida...but good luck with keeping them off even if you get rid of the one....the little ones are like roaches and mice as they seem to fit into spaces way smaller than them.
They seem to stay outside or only porches though, not in "conditioned" or high traffic areas... I would ignore the one unless I saw him in other places that I would care more about.
Rather have a lizard that eats roaches than the other way around.