This list of mythical creatures that begin with this letter and I am constantly gathering information from each continent, and is continually being updated.
Bake-kujira (Japanese)
It is a large ghostly skeleton whale and is said to be accompanied by strange birds and fish. In one story, a fisherman threw his harpoon at the bake-kujira to try to catch it, but the harpoon passed right through it, and the whale and its host just floated away into the night.
Other legends say that the ghost-whale brings a powerful curse with it. "The curse of the whale", as it's creatively called, is said to bring famine, plague, fires, and other kinds of disasters to the villages it hits. The Bake-Kujira could have been a bloated decomposing whale with the flesh eaten or rotten off showing many bones. All the fish and birds may have been there for food.