10-31-2014, 05:20 AM
My observation is that they do not currently despawn, or else the despawn is on a very long timer. I tested it today by hiding and fishing for a couple hours. In that time I pulled up two sea serpents and one deep sea serpent, none of which had despawned more than an hour after I quit fishing. I actually sailed to shore, did some town business, then sailed back out where I had fished them up, killed them, and collected the maps/MiB.