Riverine craft drawn into open-water losses

How often have brown-water forces been lured into blue water and destroyed?

More often than is usually acknowledged, in this broad assessment, which comes without examples or a count.

In this broad assessment, riverine craft have been lost at sea more often than is usually acknowledged. No named battle or numerical estimate establishes how frequent those losses were. The concern is the exposure of brown-water forces in an unsuitable open-water environment.