Restoration of Oyster (Crassostrea virginica) Habitat for Multiple Estuarine Species Benefits. A Final Report to the Piscatauqa Region Estuaries Partnership

摘要

The overall goal of the project was to make a significant contribution to the Piscataqua Region Estuaries Partnership goal of increasing oyster (Crassostrea virginica) bottom in New Hampshire, and to do so using methods that positively affect multiple species. The focus was on those organisms (mainly macroalgae, invertebrates, and fish) that spend most of their time on oyster reefs the resident species. A 0.5 hectare (1.25 acres) area was restored in August 2007 by constructing twelve mini-reefs (each approx. 6 m in diameter) in an area protected from harvest using spat-on-shell (spat seeding) from remotely set larvae. There was a consistent trend over time of higher oyster densities on the mini-reefs and on the natural reef within the protected area compared to the adjacent unprotected natural reef. At the end of the project period (1.8 years post-construction of the mini-reefs), total oyster densities in the overall restoration area were about 26% higher than the adjacent unprotected reef. The constructed mini-reefs also consistently had higher total densities and biomass of resident animals, which consisted mainly of invertebrates (only one fish was captured over the entire study), compared to the other reef areas. A total of 15 species of invertebrates were collected from the mini-reefs compared to 10 and 11 species, respectively, from the natural reef in the restored area and the natural reef in the harvested area.