Throughout recorded history, in different cultures, there have been recorded sightings and episodes concerning what is commonly identified as bobbing heads in the water or floating bodies in the water. Why?
I have a theory based on research and personal observation. This is my theory. In the moment and coming impact of death, the incident of a drowning death is registered in what many call, the ethers of time, which leaves a distinct impression that can be seen throughout time by different living people. These living people have different and varying gifts with which to see and make contact with the paranormal. Sometimes, this impact of drowning death comes and the person involved dies unaware of the drowning. This impact and situation of being aware or unaware can be logically extended to other types of unexpected and oftentimes traumatic death. There are intelligent hauntings where such bobbing heads in the water may be attempting contact, and there are residual hauntings where the scene repeats itself without the ghostly figures attempting contact. Intelligent hauntings indicate awareness on the part of the ghost. Residual hauntings indicate no awareness on the part of the ghost, only a series of repeats without contact. People see bobbing heads or floating bodies because time sequences have permanently established them in that manner to be remembered. The bobbing heads and floating bodies may sink beneath the water as quickly as they appear, but some linger. Some may linger with a purpose while others do not. We live in an existential physical universe side-by-side with the paranormal universe, and with the passage of time, the universes come together and touch. Oftentimes they do more than touch, they connect.
In modern times, this very century, there will indeed be more of that contact with tangible results. Some contacts are fleeting, but some contacts are lasting, and permanent.
There is much documentation of people seeing bobbing heads or floating bodies in a river, a lake, a cave pool of water, a canal, a reservoir, an ocean, or any body of water. They are there, then they are gone. These paranormal sightings are real, and do take place often.
As people become more alert to the paranormal activities around them, and more intuitively self-trained to such things, they will see them. In time, we may all see such things, if we trust ourselves enough to do so. That is the way of it.