Subterranean Sampling Devices (SSDs) used in the present study A schematic representation of the four different SSDs used at each sampling site and the depth at which they are buried. Arrows indicate the possibility that invertebrates may be guided deeper into the ground by the tube B photograph of a standard 1-m long SSD placed in the hole before covering C process of covering the 1-m standard SSD D short SSD placed at a depth of 90 cm, before it was covered with scree material.