Oyster Reef Restoration: Impacts on Infaunal Communities in a Shallow Water Estuary

Oyster reefs are important estuarine ecosystems that provide habitats to many species, including threatened and endangered wading birds and commercially important fishes and crabs. Infaunal organisms (i.e. aquatic, sediment-dwelling organisms) are also supported by oyster reef habitats. Infaunal organisms are critical to oyster-based food webs and are consumed by many important estuarine species. Due to their critical role in coastal food webs, infauna are hypothesized to be strong indicators of habitat productivity. With the dramatic global loss of intertidal oyster reefs, organisms that depend on oyster reef infauna are likely negatively impacted. Fortunately, oyster reef restoration is currently underway in many locations. We hypothesized it would be possible to document the transition from a dead oyster reef to a fully-functioning restored oyster reef by examining changes in infaunal communities before restoration and over time following restoration. Research was conducted in the Mosquito Lagoon of the northern Indian River Lagoon system. Three replicate samples were collected from 12 intertidal oyster reefs (four dead, four live, four restored). Samples were collected one-week pre-restoration and one month and six months post-restoration. Infaunal taxa abundance and composition were recorded. Reef infaunal abundance increased following restoration; restored reefs became more similar to live reefs over time. Live reefs consistently had high infaunal abundance and dead reefs consistently had low abundance, while restored reefs were intermediate. These data suggest restored reefs are more productive than their dead counterparts, with restoration showing a positive trajectory to support numerous infaunal species and their associated food webs