Hidden about 30 centimeters beneath the soft soil of the littoral zone are rafts of these communal hunters. Often numbering in the scores, these dart-shaped creatures lie in wait for the unwary passerby to tread on the soil directly above them. As they rely primarily on their sensitive pressure receptors, their sonar is nearly nonexistent. These short-range attack hunters are able to propel themselves with enormous velocity over short distances. They launch themselves by means of a folded, muscular "foot" that snaps the individual animal through the concealing ground toward its target. After a kill, the beachquills will instinctively regroup and bury themselves, leaving no visual evidence of their existence. Their immobility and silence are perfectly evolved hunting techniques on a sonar-based planet. As the beachquill's range is limited by the density and composition of the soil it lives in, it is found exclusively in the littoral zone.
Such prey items include Beach Lopers, which will sometimes wander into a bed of beachquills. It is not a pleasant scene: 50 or so beachquills suddenly burst from the ground around the peripheral and within seconds have punctured it mercilessly. The force of their attack is so great that the creatures that miss the prey bounce harmlessly off other objects some 20 meters from their launch-bed. The prey is dead before it hits the ground. A bizarre feast follows with the beachquills that have struck home eating their way out of the carcass, and those that have missed eating their way in. An hour later the prey's bones lay exposed on the ground and the beachquills have vanished, leaving no trace.
- In the documentary adaptation, the beachquills' featured victim was changed from a beach-loper to a Groveback.