Mud Piles

Mud Piles are brown collideable objects that can only be found on uninhabited islandss and pirate camp islands.

When interacted with, you can forage bait for fishing:
 * Grub (common)
 * Worm (less common)

Grubs and Worms are currently only used for fishing, and does not have any crafting or consumable properties.

Source

 * Uninhabited Island
 * Ancient Island
 * Pirate Camp Island