Rodent-like pests that infested Cardassian stations and plagued Deep Space Nine, chewing through systems and drawn to energy.
Cardassian voles are small, hardy rodents that thrive aboard Cardassian-built facilities. They are hard to wipe out and were a constant nuisance aboard Deep Space Nine, where they appear drawn to electromagnetic fields.
In Playing God, an infestation spread through the station as the voles gnawed on conduits and circuitry, at one point disrupting the forcefield around a tiny proto-universe in the science lab. Crew hunted them with phasers, and Miles O'Brien built a sonic device to drive them off, accidentally deafening Quark for a time.