Talk:Ocean/@comment-2001:5B0:4CCA:C410:0:FF:FEBE:61BA-20170930194050/@comment-32671756-20171001131036

They're indicators of sunken sea treasure caches, version 1.9.5 lead in a new NPC, Sea Treasure Hunter, you can randomly find him on one of the Uninhabited Islands, he will be standing next to a campfire, talk to him, start his quest and you can get a Grabber, place it on your boat and you can start hunting for those treasure caches. Good luck on that.