Enough sailing vessels under a military command can be called a navy. Maybe they just mistook some hippos as merpeople while sailing forth in their flotilla of canoes?
Manatees like to sun themselves on rocks by the ocean, though, whereas hippos like to submerge themselves in, AFAIK, fresh water. European sailors didn't make this mistake up close.
Enough sailing vessels under a military command can be called a navy. Maybe they just mistook some hippos as merpeople while sailing forth in their flotilla of canoes?
Manatees like to sun themselves on rocks by the ocean, though, whereas hippos like to submerge themselves in, AFAIK, fresh water. European sailors didn't make this mistake up close.