differences among complexity indices were associated with oyster species. Increases in
vertical reef heights and surface rugosity were observed over time for all experimental reefs,
and treatment effects were observed after 19 months of development, when C. ariakensis
reefs exceeded the vertical heights of C. virginica reefs, removing any doubt regarding the
Suminoe oyster’s reef-building capability. Spatial comparisons of reef-associated
macrofauna suggested functional equivalency between oyster species with respect to habitat
at intertidal locations (where C. ariakensis survival was low), and at subtidal sites of low
salinity. At subtidal locations of higher salinities, however, the numbers of organisms
associated with C. virginica reefs per unit of oyster biomass were significantly greater than
the numbers of organisms associated with C. ariakensis. Multivariate analyses of data from
subtidal high salinity sites also revealed unique communities associated with C. virginica
treatments, while mixed oyster species assemblages were functionally equivalent to monospecific
C. ariakensis experimental treatments. Temporal comparisons at one mesohaline
subtidal site revealed that the observed effects of oyster species on habitat function in higher
salinity locations are inconsistent over time and likely overshadowed by seasonal larval
recruitment dynamics and local hydrodynamics. Though a common oyster reef trophic
cascade between juvenile oysters, C. virginica; mud crabs, Panopeus herbstii; and oyster
toadfish, Opsanus tau was successfully replicated during mesocosm trials, specific trophic
interactions were not significantly affected by oyster substrate species or habitat complexity
(as it was defined within the constraints of the experiment). Together, these experiments
represent the first effort to quantify the potential habitat function of C. ariakensis in
Chesapeake Bay, and provide evidence of species-specific similarities and differences in
reef-associated communities.