I dunno, y'know.

The only experience I have with it is on my semi-completed project boat, and that certainly could be suffering from exposed wood and the re-hydration effect. Many stitch-and-glue boat designs are built around the idea that the wood is fully encapsulated by epoxy, so that moisture from the interior isn't an issue or shouldn't be an issue. I have noticed that on a couple of rods (stored outside-- I really need a shop!) with what are supposed to be epoxy wraps that there is a whitish discoloration appearing on the side exposed to light. I'm guessing your archery gear was stored inside, so that may be why it's not showing. And we could be talking about different epoxies as well... and the stuff you are using has UV inhibitors added, like most paints do.

My guess is that it will be a non-issue if you don't store your oars outside 24/7. If you do, you'll probably find out in a year.

Good luck on the boat-- sounds like a blast.

Keith