2011 University of Exeter (UoE) Plymouth Sound. Investigation into the cumulative small scale impacts on the Plymouth Sound SAC dataset https://portal.medin.org.uk/portal/start.php?tpc=010_bc31d375b970fa882c38e6672d856af0 In this study, this theory was examined to understand the effects of cumulative disturbances through a field based test. It examined the effects of different disturbances (crab tiling and mooring) together and separately, on the infaunal intertidal communities (Carcinus maenas and meiofauna). The results indicated that mooring appeared to increase overall crab abundance, specifically juveniles and reproductive crabs, whereas tiling showed little difference. The treatments together appeared to create an intermediate abundance of crabs (the control= 90, mooring= 260, tiling= 112 and the cumulative treatment=209). Meiofauna increased in diversity and decreased in evenness for the cumulative treatments. The individual treatments showed that tiling alone could have a positive effect shown by high copepod ratios. Biomass was shown to have no impact. This highlights the complexity of measuring disturbance. These results have shown that disturbances together do not combine to create a larger impact. However, the responses observed may also be influenced by season and other site specific factors such as history of previous disturbance. The results do not conform to the linear interpretation of the Intermediate Disturbance Hypothesis if the assumption is more disturbances creates more impact, as more disturbances did not result in a bigger impact. This highlights the difficulty to classify an optimum disturbance regime to help future conservation objectives. 20170418