Sailors of reddit, what is the most bizarre or unexplainable thing you’ve seen while at sea?

Off the coast of Venezuela, once saw what could be called a dolphin party. Apparently they sometimes team up to herd schools of tuna together and feast on them. So there was a line together of hundreds of dolphins--and I do mean hundreds. The dolphins ones at the front of that line were leaping out of the water, spinning, doing flips--not actively feeding (they seemed to have already fed) but either taking turn displaying acrobatics to each other or showing pure joy. They kept on going, leap after leap, until we had passed. Must have watched it for twenty or thirty minutes.
— doublestitch

I was surfing one time and a manatee came up right under me and started spinning. It just kept spinning until I pet it then it stopped and just looked happy.
— MemesAndCommyRegimes

There is a green flash of light just after the sun passes the horizon. when I've seen it, its was more blue green but it might have been the water reflecting thru the atmosphere moon jellyfish appearing out of nowhere. so many you couldn't jump in without hitting them. and disappearing 20 min later when the wind picked up.
— bubbleTime1

I was on a submarine, so....not much. There was one guy who used to take two slices of bread, dump a bunch of sugar on it, and cover it all in milk, and would eat it for breakfast. That was pretty bizarre. But I don't think that's what you're looking for.
— Old_and_tired

In the straights of Hormuz by Iran, we sailed through thousands of sea snakes. One slip overboard meant certain death.
— longboarder116

While sailing the tallship Bounty out the St Lawrence I was on bow watch and the ship lurched to starboard by like a foot. We had like 10 miles of water on both sides so I checked on the starboard side... nothing Went to the port side and was completely speechless for the first time in my life. A 55-65 foot Right whale was scratching it's back on the side of the ship and I was staring into a volleyball sized eye less that 10 feet from me
— olafthebent

I’m a Navy helicopter pilot and I’ve seen a few strange things. Someone already mentioned the sea snakes in the Arabian gulf. But what you can’t really see from the ship is the balls of snakes. I’ve flown over a few giant balls of snakes intertwined in the water. When I say giant, I am talking like 10 yards from side to side. In the middle of the ocean we came across a dead cow in the water. Just bloated and floating there. My best guess is the thing fell off of a freighter. I’ve seen a whale shit. That was on the list of things I never thought I’d see. A mom and her calf surfaced out near San Clemente island off San Diego, and dammit that mom let out a long brown cloud behind her that had to go for 50 yards.
— JohnnyFknUtah

Not a Sailor but worked with a Diving Boat for a long Time in eastern Thailand: once we met a swimming Dog in the open Sea, no Island for 5 nautical Miles. A few days later we asked the Locals and they explained that this Dog is doing this always (swimming) when he feel it is Time to met the female Dogs of the other Islands and sometimes even swimming to Cambodia!
— Setagaya-Observer

Was transiting at flank speed in a submarine at an undisclosed depth greater than 200 ft. Felt the entire ship shudder up and down and heard a loud thump and rumble. Shortly thereafter saw a sonar signature for a large group of snapping shrimp across the bow. Pretty sure we freed Willy...
— HiPoint_Masterace

Have you ever seen the movie Captain Philips. If they came out only 2 hours earlier they would have attacked my ship. We were just ahead of them. I only heard about it when the captain brought us all to the bridge and told us about the American ship that had been assaulted.
— EmperorOfNipples

I am a Deck Officer, this happened twice, the last one about two weeks ago. Our vessel was sailing on the north coast of Brazil, around 0200LT, I went outside to obtain the gyro compass error by taking the bearing of the Moon. It was a beautifull sky that night so I took my time out at the bridge wing to take some air. At one moment I was looking to the horizon at portside when at a glance I spotted a dim glow in the sea, when I looked down there was like hundred of thousands of green and blue glowing dots on the water, it was like I was sailing on another planet (Avatar’s Pandora, anyone?). After some research I’ve learned that these is caused by plankton bioluminescence. It was mesmerizing. Other less bizarre but really cool event was a meteor passing by. We see a LOT of shooting stars and space debris falling down through the atmosphere, but this one was the size of a bus or something, the whole night became bright as day for 3 seconds. There are some stories of UFO, and paranormal phenomena that I’ve heard through this years that happened with my coworkers, but as these didn’t happened to me I will keep to another post, if you guys are interested!
— Lage88

Did a semester with an Outward Bound program where we sailed through the Exumas in the Bahamas for two weeks. Every night while we slept we would have anchor watch shifts so that someone was always awake if we started to drift. On my watch one night I saw a fairly large dark object (6-7 feet) pass under the boat and keep going till it was out of sight. Couldn’t make out what it was since it was so dark out but wish I knew what it was. Probably a shark I guess?
— VegetableYak

Very similar to doublestich's comment, was in the Marblehead to Halifax race, off the coast of Nova Scotia, and while at the helm saw we were heading for what looked like a weird reef or shoal. We are looking at charts, everything we had, nothing. And we were approaching it too quickly, but really it was approaching us. Dolphins chasing tuna in a huge event, like 1/2 mile wide, like a huge line of white water it really was bizarre. \- Also a few time an [Ocean Sunfish](https://en.wikipedia.org/wiki/Ocean_sunfish) would follow us, drafting us \- just 3\-4 feet off the stern. NOTHING should be that big and that ugly... \( well except for OP's mom \- sorry obligatory Reddit comment\)
— geek66

Saw a soccer ball go floating past one time when we were several hundred miles from land. Also sailed past the carcass of a goat in the middle of the Persian Gulf.
— thegeekwholived

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