Atylus swammerdami displays no clear preference for sediments with a specific grain size: the species is found in sediments with median grain sizes up to 550 μm with a low relative occurrence. However, a clear preference can be seen with regard to the mud content. Atylus swammerdami reaches a relative occurrence of over 40% in sediments with a mud content of 30-40%. The species is nevertheless also found in sediments with lower or higher mud contents (up to 50%).