I am always amazed at the way these cruise ships sit on the water. I understand the theory of bouyancy and what’s going on, but if you take out the Physics, then you must feel a sense of amazement. It looks like a reverse of the iceberg principle with more of the ship above the water than below it.
This particular ship was edgeing it’s way through the channels between the mainland and Vancouver Island. I hope the passengers on board had taken time to spot the Orcas as they rose around the vessel. I was travelling along in yacht, made of concrete, hoping for enough wind to sail rather than use the engine. The guide who owned the boat was a specialist in whale photography and he recounted the tale that Orcas had been spotted "surfing" the wake from the propeller of these ocean going cruisers.
Presumably they are catching something in the wash, but it is much nicer to think that they like swimming behind these large ships just for fun.