sled Misses deep burrowing animals since it can only cut through sediment up to 2 cm deep If an accurate density is needed of the macrofauna, grab samples or box cores would be more accurate. However the sled is useful for collecting rare species and for providing information on an area that is not well studied. Sherman (sled) The Sherman epibenthic sled is used for rough terrain. In 1997 an epibenthic sled was designed by CSIRO to sample invertebrates from seamounts. Older epibenthic sleds were unable to sample in this rough terrain. Changes were made to make it more rugged. The bracing was enhanced and the runners were thickened. They also improved the cutting plates and made infaunal collection optional. See also Benthos Van Veen grab sampler References Oceanographic instrumentation