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Restoration of degraded ecosystems is an important societal goal, yet inadequate monitoring and the absence of clear performance metrics are common criticisms of many habitat restoration projects. Funding limitations can prevent adequate monitoring, but we suggest that the lack of accepted metrics to address the diversity of restoration objectives also presents a serious challenge to the monitoring of restoration projects. A working group with experience in designing and monitoring oyster reef projects was used to develop standardized monitoring metrics, units, and performance criteria that would allow for comparison among restoration sites and projects of various construction types. A set of four universal metrics (reef areal dimensions, reef height, oyster density, and oyster size-frequency distribution) and a set of three universal environmental variables (water temperature, salinity, and dissolved oxygen) are recommended to be monitored for all oyster habitat restoration projects regardless of their goal(s). In addition, restoration goal-based metrics specific to four commonly cited ecosystem service-based restoration goals are recommended, along with an optional set of seven supplemental ancillary metrics that could provide information useful to the interpretation of prerestoration and postrestoration monitoring data. Widespread adoption of a common set of metrics with standardized techniques and units to assess well-defined goals not only allows practitioners to gauge the performance of their own projects but also allows for comparison among projects, which is both essential to the advancement of the field of oyster restoration and can provide new knowledge about the structure and ecological function of oyster reef ecosystems. [ABSTRACT FROM AUTHOR]

Eastern oyster ( Crassostrea virginica) habitat is increasingly being restored for the ecosystem services it provides rather than solely as a fishery resource. Community-based projects with the goal of ecological restoration have successfully constructed oyster reefs; however, the habitat benefits of these restoration efforts are usually not assessed or reported. In this study, we examined oyster habitat development at five community-based oyster restoration sites in South Carolina using oyster population parameters, resident fauna densities, and sedimentation (percent sediment coverage) as assessment metrics. All sites included multiple-aged reefs (1–3 years old) at the time of the fall 2004 sampling. Resident crabs and mussels were abundant at all five sites and crab assemblages were related to the size structure of the oyster microhabitat. Scorched mussel ( Brachidontes exustus) abundances were most frequently correlated with oyster and other resident species abundances. Associations among oysters and resident crabs and mussels were not evident when analyses were conducted with higher level taxonomic groupings (e.g., total number of crabs, mussels, or oysters), indicating that species-level identifications improve our understanding of interactions among reef inhabitants and oyster populations. Community-based restoration sites in South Carolina provide habitat for mussels and resident crabs, in some cases in the absence of dense populations of relatively large oysters. Monitoring programs that neglect species-level identifications and counts of mussels and crabs may underestimate the successful habitat provision that can arise independent of large, dense oyster assemblages. [ABSTRACT FROM AUTHOR]

A series of experiments was conducted to evaluate the distribution and abundance patterns of two species of macrophyte-inhabiting caridean shrimps found in Apalachee Bay, Florida, USA. Experiments using Palaemonetes vulgaris and Palaemon floridanus included microhabitat association and behavioral interactions. Predator-prey relationships, as they apply to habitat complexity and interspecifc interactions, were also examined using the pinfish, Lagodon rhomboides, a natural predator. Pt. vulgaris individuals were excluded from the experimental habitats by P. floridanus over a range of densities. We conclude that their nonoverlapping microgeographical distribution is primarily a consequence of interspecific competition rather than just microhabitat selection. Predation success on single species was inversely related to the physical complexity of the experimental habitat. However, when placed together, a significantly greater proportion of Pt. vulgaris is consumed than P. floridanus. We posit that the displacement of Pt. vulgaris from cover by P. floridanus significantly increases the former's risk of detection and capture. The importance of refuges in regard to: (1) seagrass predator strategies; (2) prey tactics, and (3) species abundance and richness patterns in macrophyte-dominated communities are discussed. [ABSTRACT FROM AUTHOR]