The frequency of mechanical beach cleaningwas found to be the most influential predictor of ghost crab burrow densities in Sydney Harbour.
This is consistent with studies globally, that have identified mechanical beach cleaning as a highly disturbing process on
sandy beaches.
For example, found species richness, abundance and biomass of wrack-associated macrofauna was significantly reduced on beaches that were mechanically cleaned in contrast to those that were not cleaned.
Similarly, Gilburn (2012) reported reductions in macroinvertebrate biodiversity on sandy beaches that were mechanically cleaned.
In this study, however, we classified beaches by the frequency of mechanical cleaning, and found reduced burrow densities at the most intensively cleaned beaches while beaches that were infrequently cleaned (up to three times per week) supported the highest densities of ghost crab burrows.
These results suggest that ghost crab populations within Sydney Harbour are resilient to moderate levels of human disturbances.
Similar results were found by who found that a moderately disturbed beach had higher ghost crab burrow density compared to a disturbed beach, although this difference was not significant.