Protection mutualists affect colonization and establishment of host-associated species in a coral reef cryptofauna community

Protection mutualists display territorial behaviors that provide protective services for their host species. To investigate how protection mutualists impact the colonization and establishment of host-associated species, we conducted a two-stage experiment using a coral reef cryptofauna community as our study system. Pocillopora meandrina is a fairly common, branching coral species that forms habitat that is utilized by a variety of marine organisms. There is a guild of protection mutualists that associate with P. meandrina including Trapeziidae crabs and Alpheidae shrimp. We manipulated coral colonies to have Trapeziidae crabs, Alpheidae shrimp, both, or neither. For the first part of our experiment, we observed colonization of marine invertebrates to these colonies every other day for two months, while resetting the treatment levels every seven days. For the second part of our experiment, we surveyed the community composition weekly and then monthly for a total of six months without in...