Back in the 70s, I worked in a hospital laundry. We washed a few things other than bed sheets! We found afterbirths and bits of human flesh. Don't forget the used adult diapers. But not everything was bad ----------- a co-worker found $100. He got to keep it.
When we (Canadian Navy) traveled in tropical waters I can't recall seeing much interesting stuff other than flying fish and dolphins frolicking around the bows of other ships in our squadron. Spent most of our sea time in northern waters where you never see much of interest. Sometimes out in the middle of the ocean these cute little birds appeared out of nowhere to perch on superstructure maybe to rest their wings for a while.
They don't teach that in school here because the recruiters were having trouble to find many young Canadians willing to join the Navy -so they could advertise 'join the Navy and see the world'.
Dunno honestly. When wartime (WWII) came everybody's first thought was to join the Army. (All my uncle) When my dad applied to join -the Army had their quota of recruits so he went Air Force. I joined Navy just to break tradition and do something different. I was the oddball -Noone else that I know of ever joined the Navy.