When playing in multiplayer mode (Open to Lan, in this case, but also on Realms), If one player gets into a boat and travels beyond the other player's render distance, the first player appears at the location they left the shore to get in the boat. When he returns to within the second player's render distance, his ghost disappears from the land.

In the attached pictures, I am showing as a ghost on the shore in the first image, but in the third I am actually in my boat, returning to her render distance near the cactus. The order appearing below is not the order taken.