Oyster Reef Restoration Project for the City of Dover, Grizzle

This project was conducted as a contract between the City of Dover and the University of New Hampshire, with additional funding supplied by the New Hampshire Estuaries Project. The overall goal was to restore as much bottom area as possible (with available funds) of formerly productive oyster bottom in two areas, the Bellamy River and Pomeroy Cove (Piscataqua River). The restored areas were intended as a contribution to the long-term NHEP goal of restoring 20 acres of oyster bottom by 2010 (Trowbridge 2003). Five objectives were addressed: (1) site surveys, map production, and final restoration protocol development; (2) remote setting of oyster larvae; (3) bottom seeding with spat; (4) assessment of restoration success; and (5) education. Site surveys found substantial amounts of shell bottom (but only two live oysters) along a 1.2 km stretch of the Bellamy, and no oyster bottom off Pomeroy Cove. Hence, restoration efforts were designed only for the Bellamy. Spat seeding involving deposition onto the existing bottom (i.e. no bottom improvement via placement of additional hard substrate or other methods) of spat (young oysters) attached to shell substrate produced by remote setting was chosen as the primary reef restoration method. Larvae from native Great Bay oysters were set in tanks at UNH\u27s Jackson Estuarine Laboratory (JEL) in July 2005, and held on a nursery raft at JEL until reef construction in November 2005. Approximately 300,000 spat-on-shell were used to construct 12 mini reefs (total surface area ~0.1 acre) within a 1.5-acre overall restoration area. On 26 July 2006 (9 months post-construction), 32,000 live oysters remained on the mini-reefs and no live oysters were found in adjacent natural reef areas. When considering only the 0.1 acre area covered by the mini-reefs, live oysters occurred at 64/m2, which is similar to oyster densities in other areas in Great Bay. When considering the entire 1.5 acre restoration area, live oysters were at ~4/m2. The entire 1.5-acre area was considered restored in the short-term. Longer-term restoration success will be dependent upon successful natural recruitment to the mini reefs as well as the adjacent bottom areas. Diver observations in July 2006 indicated that very little oyster shell (other than what was put out with the spat in November 2005) remained in the restoration area. This suggests that longer-term restoration success may require placement of additional shell onto the bottom. Longer-term success will be assessed by future sampling as funds become available

Soft-Shell Clam (Mya Arenaria) Distribution & Abundance at Selected Sites in the Great Bay Estuary

Previous surveys (1996 to 2002) provided distribution and abundance data for soft-shell clam (Mya arenaria) populations in ten areas of the Great Bay and Piscataqua River estuaries identified as potentially good clam habitat. The present study was designed to complete the overall survey by sampling six remaining areas: Weeks Point, Brackett\u27s Point, Squamscott River mouth, Moody Point, Herods Cove, and Upper Little Bay (western shore). The objectives of the present project were to: (1) visually inspect the six study areas for the general distribution of sediment types and soft-shell clams, (2) quantitatively sample the six areas to determine densities of soft-shell clams, (3) produce GIS maps based on the survey data, and (4) assess clam distributions considering data from the present study and previous research. At each of the six sampling areas, the approximate boundary of potential clam habitat (=intertidal soft sediments) was determined by visual inspection at low tide. Notes were made on changes in major sediment types, the presence of clam siphon holes, and empty clam shells. At each site, nine to fourteen 0.125 m2 quadrats were haphazardly tossed onto the sediment surface, excavated to at least 20 cm depth using clam rakes, and all excavated sediments washed through a 5 mm mesh sieve. All clams retained on the sieve were measured (shell length to nearest mm with calipers), counted, and returned to the general area. A sample of the upper 5 cm of sediment was collected from each quadrat and stored at Jackson Estuarine Laboratory. Quadrat locations were geo-referenced using DGPS.The general environmental conditions in all six areas appeared suitable as soft-shell clam habitat. However, very few live clams were collected and very few empty shells were observed. From a total of 65 excavated quadrats, only 8 live clams were collected with mean densities ranging from 0.0 to 3.1/m2 at the six sites. It was concluded that none of the six areas were productive clam flats at the time of sampling, and they probably had not been in the recent past. Previous research and the present study indicate that many of the expansive intertidal flats in the Great Bay/Piscataqua River system have not been productive clam habitat for decades, probably since at least the 1940s in some areas. However, moderate to high densities of clams have been reported in some areas, particularly in sandy sediments. Previous research also showed high densities of early post-set clams in some areas, suggesting that spat mortality (probably predation effects) may be an important cause of low densities of larger clams in these areas. Future research should focus on sandy sediments and mixed soft sediments with cobble to better characterize the distribution and abundance of clams in the Great Bay/Piscataqua River system. Future research also should assess the role of predation on newly set spat in controlling clam populations

Reef Structure Alternatives for Restoration of Oyster (Crassostrea virginica) Populations in New Hampshire

Eastern oyster (Crassostrea virginica) populations in New Hampshire have experienced severe declines since the 1990s, and restoration of oyster populations has been a major goal for New Hampshire management agencies. The most widely used technique in recent years in New Hampshire has been spat seeding which involves setting larvae from disease-resistant and/or fast-growth broodstock onto cultch material in large shore-based tanks, then distributing the spat attached to cultch onto the bottom to initiate reef restoration. This approach has the dual potential of providing direct population enhancement as well as introduction to the local gene pool of disease-resistance and/or fast-growth potential. Although spat seeding has been shown to be an effective technique much remains to be learned about the overall restoration process, particularly specific design criteria, the most effective combinations of methods, and long-term viability of restored bottom areas. The present project was designed in part based on results of earlier experimental work (mainly the use of spat seeding) to address the general management question: How should reefs be structurally enhanced (if at all) to enhance oyster populations and improve spat set

Development of a Florida Seafood Program Using a Multi-Disciplinary Team

The seafood industry in Florida is complex, with more than 80 varieties of Florida seafood commodities and an increasing number of imported products. This variety increases consumer confusion, especially with the growing concern about the origin, sustainability, and safety of seafood products. The objective of the Florida Seafood At Your Fingertips program is to provide Florida Extension agents with updated, science-based information regarding seafood, which will result in increased consumer awareness and consumption. Combining a survey instrument, curriculum modules, public displays, and a mobile application with the teaching expertise of Extension has allowed this program to reach consumers throughout Florida

Effects of a Large Fishing Closure on Benthic Communitites in the Western Gulf of Maine: Recovery from the Effects of Gillnets and Otter Trawls

The recovery of benthic communities inside the western Gulf of Maine fishing closure area was evaluated by comparing invertebrate assemblages at sites inside and outside of the closure four to six years after the closure was established. The major restriction imposed by the closure was a year-round prohibition of bottom gillnets and otter trawls. A total of 163 seafloor sites (~half inside and half outside the closure) within a 515-km2 study area were sampled with some combination of Shipek grab, Wildco box corer, or underwater video. Bottom types ranged from mud (silt and clay) to boulders, and the effects of the closure on univariate measures (total density, biomass, taxonomic richness) of benthos varied widely among sediment types. For sites with predominantly mud sediments, there were mixed effects on inside and outside infauna and no effect on epifauna. For sites with mainly sand sediments, there were higher density, biomass, and taxonomic richness for infauna inside the closure, but no significant effects on epifauna. For sites dominated by gravel (which included boulders in some areas), there were no effects on infauna but strong effects on epifaunal density and taxonomic richness. For fishing gear, the data indicated that infauna recovered in sand from the impacts of otter trawls operated inside the closure but that they did not recover in mud, and that epifauna recovered on gravel bottoms from the impact of gillnets used inside the closure. The magnitudes of impact and recovery, however, cannot be inferred directly from our data because of a confounding factor of different fishing intensities outside the closure for a direct comparison of preclosure and postclosure data. The overall negative impact of trawls is likely underestimated by our data, whereas the negative impact of gillnets is likely overestimated