Gribbles Nibble

Gribbles do more than nibble, they destroy wooden docks. Limnoiriids (gribbles) are one of two species of wood boring isopods found in Florida waters.  Gribbles use their mandibles to attach themselves to wood and initiate their burrow. Much like ship worms, gribbles can tunnel into a wood structure with little outward signs of damage because their initial burrow is the size of a pin prick.

These wood consuming crustaceans are nearly transparent and an adult is only between 6-10mm in size.  They reproduce inside the wooden structure and their spawn set off creating their own tunnels. As they burrow, they create tiny vents in the wood, making the infected timber appear to have fine pores.

Pilings that are infested with gribbles beyond the point of repair often have an hourglass shape. Once a wooden structure has been heavily infested, gribbles will swim to nearby wooden structures to start new colonies. Catching a gribble infestation early is key to the survival of a dock. Wood structures should be cleaned and inspected for signs of the tiny gribble burrows. Proactive measures, like wrapping pilings in vinyl, can be taken to prevent or kill off a wood borer infestation.

Adult gribbles are only 6-10mm in size. and they are almost transparent. These wood-eating crustaceans use their mandibles to attach to a structure.

Gribble colonies start with a burrow the size of a pin prick. This piece of driftwood has been consumed with burrows and vents that gribbles make to increase water and oxygen flow.

They breed inside the wood, each generation making their own tunnels, leaving a shell of the original structure.

Gribble infested pilings often have an hourglass shape.