In my very, very limited readings of maritime disasters, I’ve come across two accounts where starving, adrift survivors drew straws to determine who would be killed and eaten by the other survivors. One was from “In Heart of the Sea: The Tragedy of the Whaleship Essex”, which is the story of a ship that was wrecked by a whale. The other was from a book of the history of Hilton Head, GA (don’t remember the name), which recounted the experience of some settlers who were low on food and tried to sail back to Europe. As I’ve only read a handful of books on this topic (4-5?), it seems surprising to me that two of them had stories of people somewhat voluntarily agreeing to be victims of cannibalism. I’m sure that there are many cases where living survivors ate dead bodies out of desperation, but that would commonly be when the people were already dead because of injury or starvation on their own. In these two cases I came across, living survivors draw straws themselves knowing that if they draw the short straw, they will be killed and eaten by the others. Was that something which happened from time to time, or did I just happen to come across the two times when it happened?
The relevant Wikipedia article mentions a seventeenth century case of people who sailed from Saint Christopher Island, and a nineteenth century case of a yacht called the Mignonette. I don’t know about the Hilton Head case you referred to.
There is a very creep ,coincidence involving in this case.
In 1838 Edgar Allan Poe wrote a novel called The Narrative of Arthur Gordon Pym. At one point during the book a group of sailors are stranded in a boat and decide to draw lots to see who will be eaten. The loser is a cabin boy named Richard Parker.
In the above mentioned case from 1884, the yacht *Mignonettei sinks and four men are set adrift. After weeks without food, they decided that one of them should be sacrificed as food for the other three The loser was a cabin boy named Richard Parker!
There could have been many unknown cases when the rest of the crew were never heard from again. People have to be in pretty bad shape before they get to that point, it’s a choice between everybody starving to death or one person being eaten. At that point I think the sailors would prefer the chance of death to the inevitable starvation and just needed a means to pick the one to die.
Nothing factual to contribute but it seems to me that if you have a group of guys of roughly equal health then, by the time that one of them would die, the others would also likely be near the point of death and beyond the ability to dismember and prepare the body of their fellow for consumption.
In a case like the Donner Party where you have people of varying ages, fitness levels, and engaging in a variety of activities of greater and lesser risk, then you have the opportunity for some to die earlier in the crisis and provide nourishment to the others while those others are still somewhat capable.
Survival at sea might mean taking certain actions - not just lying around trying to use as little energy as possible. Maybe you’re fishing, doing something to try and collect/purify water, adjusting sails and ropes, etc. It might not be feasible to let everyone diminish to the point of near-death if you want to allow some of the group to survive. There might come a point where it’s the death of one or the death of everyone.
My feeling would be that this would be very circumstance dependent. It would also depend on there being someone willing to stand up and say it, early in the process.
So surely it would only actually prolong life in cases where there was plenty of drinking water, but no food. How common is that in shipwreck situations? Can you survive on sea water (and urine) alone for the 2+ weeks it would take for lack of food to be life threatening?
While it’s not confined to maritime examples, the TVTropes page “No Party Like a Donner Party” lists quite a few “Real Life” examples.
As soon as I saw the title of the thread, I thought of In the Heart of the Sea. If you are into true survival stories, its hard to beat. Supposedly, Moby Dick was inspired by this (almost) unbelievable tale. The drawing of straws was pretty disturbing.
Just as an aside, this was made into a film, which in my opinion is inferior to the excellent book.
I’ve read several books on maritime disasters. The wreck of the Medusa is a wonderful tale! 
In my recollection, far more common than drawing straws is the situation where one survivor dies - either from injuries incurred in the wreck, from drinking seawater, or just giving up/weak constitution, and the survivors grapple with whether or not to eat them.
Fortunately, we have rare video footage of just such a situation.
And drawing straws was not restricted to lifeboat situations.
Eating the dead or even murdering someone in order to eat them is somewhat expected given human nature and all. It was more the act of a group engaging in voluntary cannibalism that was surprising. But I guess it was not totally rare if they gave a name to the act: “custom of the sea”. That’s a little too casual sounding for my preference. It sounds like something fun you do when you’re aboard a cruise ship. I’ll have to remember that if I’m at sea and my shipmates ask if I want to play “custom of the sea”.
I found a reference to the Hilton Head instance I mentioned in the OP:
SC, not GA.
A pilot buddy of mine from my private flying days is a big guy, 6’7". We were discussing Alive, and I tried to convince him that if we went down in the mountains and survived the crash landing, we should behave rationally rather than drawing straws… and that the rational approach is that I should eat him. Given our relative body mass, I could last much longer eating him and he would last eating me.
His response was “We’ll see.”
“You needn’t eat the leg, Thompson. There’s still plenty of good meat. Look at that arm.”
“I’d rather eat Johnson, sir!”
Obligatory media reference…
https://montycasinos.com/montypython/scripts/lifeboat.php.html
Oops. Ninja’d
I thought that term was more applied to what sailors got down to during long periods of time with no women-folk about.
Either way, having a term for it doesn’t mean it was necessarily common. The idea captured the imagination, even if very, very rare.
Are we sure that they drew straws, or did anything else semi-willingly? Remember, the only accounts we have of this practice are from the survivors. If it hadn’t been voluntary at all, and they just overpowered the one they were able to overpower, then they’d be highly motivated to lie and say that it was voluntary.
Drawing straws is good cover for a group of survivors who murdered someone so they could eat them. A lie that saves the survivors from the gallows and makes the victim’s family feel better.
God was my copilot, but we crashed in the mountains and I had to eat him.
I’m pretty sure it is from the Essex (but it might have been a different book) - but there was quite a bit of discussion as to exactly what happened in the different boats. Were weaker people killed, or did they die. But it was pretty clearly understood by all that cannibalism - even of those who naturally died - would not cast them in a favorable light.
There were also geographical and ethnic prejudices that came to bear. And the extent to which they remained faithful to deference towards officers.
I find it fascinating, how people deal with such extreme situations. Not only individual castaways, but also polar explorers. Made of far sterner stuff than yours truly!
There was a polar expedition where one member turned out to be a sociopath, and the other members killed him because they knew they would all die otherwise. He was stealing food, among other things. I also know of another voyage where this European crew had an African slave, and I think we can all guess what happened to him. As far as they were concerned, he was livestock.
Also, the Donner Party and the “Alive” people made universal decisions not to eat relatives until they were all that was left.
Carla Tortelli-LeBec : Yeah, sure Sammy. Today it’s how many bolts are in the floor. Tomorrow, they’ll have him onto if the Brady Bunch crashes in the Andes, who’s going to eat who first.
Woody Boyd : They’ll probably eat the maid cause she ain’t kin.
Cliff Clavin : Well, you know but if they’re smart, they’ll ask her first how she should best prepare herself.