“Worm grunting” is a curious but popular practice for harvesting earthworms in Florida’s Apalachicola National Forest. To summon earthworms to the surface, worm grunters drive a wooden stake into the soil and vibrate it. Panicked worms pour out of the ground and thousands can be gathered in just a few hours. Lifelong worm grunters (and there are families that have been professional worm grunters for multiple generations) have a variety of theories regarding the underlying mechanisms of their trade. However, Kenneth Catania, a researcher from Vanderbilt, has come up with an explanation to this vexing mystery that has kept so many of us lying awake in our beds night after night after night: the vibrations mimic the movements of a hungry mole, the earthworm’s arch nemesis.
Grunt like a mole, boy!
A worm grunter marks the location where he “done seen worms”
These interesting conclusions are summed up nicely in the PLoS One abstract:
“Previous investigations have revealed that both wood turtles and herring gulls vibrate the ground to elicit earthworm escapes, indicating that a range of predators may exploit the predator-prey relationship between earthworms and moles. In addition to revealing a novel escape response that may be widespread among soil fauna, the results show that humans have played the role of ‘rare predators’ in exploiting the consequences of a sensory arms race.”
The mole was not amused
Thanks to Chris “Good Ol’ Boy” Cleveland, worm grunting and enterprise search guru, for sharing.