Open the image in a new tab and enlarge. It’s three seals.
#7. OK, that seals it!
I copied the image to a photo program, then copied the image of a seal from Google, resized and placed side by side.
You have something there. Head shape very similar. The arch of the back very similar. It could very well be 3 seals, but in Lock Ness? Three of them going in single file?
My bet is an eel like creature with a head similar to a seal.