How did the Jevenile Ghost get into the Lost River?
The spawning grounds are in the Bulb Zone (I think it's the Bulb Zone, please correct me if I'm wrong), so how did that Ghost get all the way to the Lost River?
Actually, the nesting grounds are in the Tree Cove, which is a section of the lost river. Juvenile ghosts hatch from the cove and grow up in the lost river, where they then migrate outside once they reach adulthood, and finally travel to the crater edge where they continue growing until they die.