The burrowing sand lance Ammodytes japonicus (Teleostei, Ammodytidae) prefers benthic sediments of low shear strength

The sand lance Ammodytes japonicus in the Seto Inland Sea burrows into sandy benthic sediments to rest, escape predation, and estivate. To investigate the physical properties of the sediments preferred by A. japonicus, we conducted a laboratory experiment measuring the incidence at which individuals burrowed into different types of benthic sediments collected from the Mihara Strait, a part of the Seto Inland Sea, Japan. Using stepwise multiple regression analyses, we confirmed that shear strength was the most important factor explaining variations in the mean number of A. japonicus burrowing into a given sediment. The number of burrowed individuals was the highest in sediments with low shear strength, suggesting that the ease with which burrowing A. japonicus individuals can penetrate the sediment strongly affects habitat preference.