I’m guessing that if the photographer offered up his 87 previous photos that would answer the question to this particular shot.
The splashes in front of the second two “humps” is suspicious. Would a snake-like animal like “Nessie” cause a splash as each hump enters the water?
No.
But it would make a wake as it breaches, just as seen here. Only a "Nessie" would swim like that...