There was a show on National Geographic today, the picture was a hoax, set up by an invvestigator who had been fired after he had discovered "strange" footprints.
Those were faked too -he had used an hippo-foot-shaped ashtray-
When he was discovered he and his step-son made a little improvised submarine with that particular shape sticking out.
I always thought it was an elephant snout, sticking up from the water.