Oyster reefs, which are valued for providing essential fish habitat, were historically abundant throughout the Western Atlantic and U.S. Gulf of Mexico yet have been severely degraded throughout this range. For instance, Half Moon Reef in Matagorda Bay, TX, was originally 500 acres, but intensive dredging throughout the 1900’s destroyed the infrastructure of the reef and led to the collapse of local oyster populations, before being partially restored by The Nature Conservancy in 2013. The purpose of this study is to estimate the enhancement of fish and macroinvertebrate production resulting from this restoration. Fish and macroinvertebrate samples have been collected via suction sampling and modified epibenthic sled surveys on the reef quarterly for the past four years. These data are being used to calculate the per-unit-area enhancement of faunal production expected from the restoration of oyster habitat. Preliminary analyses indicate that Half Moon Reef has enhanced overall faunal biomass compared to surrounding unrestored areas. In particular, the reef supports greater biomass of mobile crustaceans including Menippe adina, Petrolisthes sp., and Panopeus herbstii, and fish including Hypsoblennius hentz, Gobiesox strumosus, Gobiosoma bosc, and Opsanus beta. The information gained from this study will help inform expectations of faunal enhancement that could be derived from future restoration efforts in the region.

The Eastern oyster, Crassostrea virginica, is a foundational species that enhances estuarine ecosystems by performing numerous ecological functions, such as filtration of water, provision of complex three-dimensional habitat and food for nekton, and stabilization of shorelines via mitigation of erosion processes. In summer of 2017, approximately 600 meters of oyster reef were restored using recycled oyster shells in St. Charles Bay, TX to support the establishment of a self-sustaining oyster population and improvement of ecosystem services and benefits. Ecological monitoring is being conducted to quantify the effects of restoration on oyster recruitment and health and faunal community metrics for nekton and infauna. We hypothesize that the density and size of oysters on the restored reef will become more similar to reference reefs over time. We also expect that the restored oyster reef will support higher densities of infauna and nekton compared to the adjacent, unstructured bottom. Preliminary assessments of the restored oyster reef indicate that reef-associated macrofauna biomass, infaunal abundances, and the number of live oysters all show increasing trends when compared to reference areas. Dermo (Perkinsus marinus) oyster disease has been observed in oysters at both reefs with severity dependent on bay conditions. Continued monitoring will provide a better understanding of the effects restoration efforts have on important estuarine species and ecosystem service provisioning, and support decisions in management, conservation, and restoration planning of oyster reef habitat.

Artificial Reefs are known to increase fish availability but little is known about their larger effects on the ecosystem. Recent research at four artificial reef sites in the Mississippi Sound suggests that the ability of artificial reefs to enhance primary production may be limited to depths within the shallow photic zone. The goal of this research is to look at the effect of artificial reef habitat on ecosystem productivity. We address these questions: are artificial reefs biogeochemical hotspots with increased rates of primary productivity and what the relationship between the attach algae is and how it influences oxygen fluxes on the reefs. We measured primary production on plexiglass plates that were deployed on an artificial reef in 14 m of water. Biofilm growing on the plates were collected from the field after being deployed for a few months, next they were placed in water filled chambers in a controlled temperature environmental chamber. Changes in oxygen concentrations over time in the light and dark were monitored and used to calculate primary production and respiration. Following the incubations, plates were scraped to collect chlorophyll a and total biomass as dry weight. We found that higher chlorophyll a fluorescence levels correlated with higher oxygen net production. Higher averages of attach epifauna were observed in the summer months with the highest average of 1.94 mg/cm2. We also examined how environmental factors such as temperature, nutrients and light that could also influence the benthic microalgae community.