Understanding the relationship between animals’ movement and their environment is crucial for fisheries and species management. There is currently a lack of detailed information about the movement of slow moving benthic species, especially for species of ecological or commercial importance. Here we document the relationship between diel movement and environmental parameters in a groundwater-fed coastal inlet for the queen conch (Lobatus gigas Linnaeus 1758), an important fisheries resources of the Caribbean region, using 3D accelerometers and video cameras. Our results show immature queen conch (n=9) spend most of their active time grazing, exhibiting two main distinct movements we characterise as a ‘leap’ and a ‘drift’ mostly used to access new foraging resources. When overturned, they ‘flip’, producing a movement with the highest acceleration recorded in order to limit exposure and restore normal position. Movement patterns appear to be significantly affected by the oxygen concentration in bottom water, with lower activity during low-oxygen levels in the morning (probability of 0.75 to observe zero movement per hour) and maximum activity during the afternoon when oxygen concentration is at its maximum (probability of 0.80 to observe >10 movements per hour). Salinity and temperature had little effect on movement patterns. Our results confirm that highly variable marginal habitats like groundwater-fed inlets are suitable for juvenile conch growth and should be included in efficient conservation plans.