anyone knows how these shipwrecks/debris piles work?

[leadpainter]

recently started spotting these on beaches, 28 per, 12 exp. seems to give a random item, one gave me a rock and another one gave me a squirrel tail.
random inventory item from drowned players? I havent seen anyone mention these before

[Beezer12Washingbeard]

Things dropped in the water in any part of the world can show up in the vrakgods (beach trash/jetsam).

I got 3 free waterskins in the first few days of w10 thanks to beach trash

[MagicManICT]

To note, these items can be fished up whenever you wouldn't have caught a fish, too.

90% is just other people's trash, but sometimes you can find dead animals (swans, mallards, rabbits, etc), arrows, curios, gear... It gets really interesting as people start dying from drowning and such.