Do we have to include generic terms in the name of objects, that in the map clearly belong to the category described by the generic?

In American maps and atlases it is the custom to always add the generic 'island' to any insular object. This has no equivalent in Dutch usage: in Dutch atlases Vancouver Island is simply rendered as Vancouver (the location of the name in the map makes it clear that the object refered to is an island); the Isle of Wight is simply refered to as Wight.

Another American custom is to leave out the generic 'river' in river names, even if the specific element is an adjective. So on a map of the United States we will find the following river names: Mississippi, Missouri, Hudson, Platte, Red, Ohio, Colorado, Columbia. This also conflicts with Dutch habits: in the Dutch language, when the specific element of a river name is an adjective, the specific element should be added. The river name Red on the American map would be converted in the river name Red River on the Dutch map. Just as the name Long Island is used instead of just Long, because Long is recognized by Dutch spreakers as being an adjective. In such cases, local usage is overruled.