"Naval Superstitions – A Sailor’s Antiquated Guide to ..." Topic

…Avoiding Bad Luck.

"…Growing up in Wisconsin, sailors and maritime life was not something familiar to me. Most of my impressions of sailors came from movies, television, and books, and one theme always stuck out more than any other: they were just a little bit spooky! There always seemed to be an air of mystery or hidden knowledge in their words and actions. If a sailor gave a cryptic warning, you could be sure the protagonist who didn't listen would find themselves regretting the choice later. Or the sailor would do something that seemed nonsensical or mad, only to have it be what saved the man from catastrophe in the end.

While I know now that the average sailor is not very spooky at all, these portrayals of seamen come from the rich history of superstition that surrounds sailing and maritime culture. For hundreds of years, humans have traversed the seas, and early on these sailors realized the powerful and mysterious nature of the ocean and currents. Going out into that big, blue expanse with little to no guarantee of returning would make most of us turn and reach out for anything that could give us a semblance of control over our situation. And in many ways, that is where superstitions come from. A semblance of control. When faced with the power and might of the ocean, who wouldn't want that?…"
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Amicalement
Armand

sigh.

lots of reasons for those:
Do not cut your hair, shave your beard, or trim your nails. Personal grooming is bad luck for the ship.
personal grooming requires fresh water, which is in short supply even on nuclear-powered ships that can distill it from the ocean

No whistling! You don't want to "Whistle up a storm" by
accident.
sailing ships relayed sail changes via whistle call the way infantry used bugle calls. whistling could result in changing the sail setting, which could dis-mast the ship or worse!

No women! They anger the sea by distracting the crew. (Unless, ironically, they're naked, in that case they calm the sea. This is why many figureheads are bare breasted women.)
no, they cause fights among the crew, which gets the ship killed

(smile)

Amicalement
Armand

Thanks Lion

To reinforce Lion's point about whistling, it's also bad luck to whistle back stage in a theatre – the men operating the 'flies' were usually navy men, and you can see why:

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