Another thing to consider is drain on your battery. Converting from DC to AC is less than 100% efficient -- you're heating your boat with energy from your battery. If you can skip that step and use DC lighting you'll save money by not buying an inverter, reduce clutter and complexity on your boat, and your battery will likely last longer during your night of fishing.

Not to mention that most inverters are not designed for a wet environment, whether you're talking safety or longevity of the unit.