Restoring Native Oysters in Great Bay Estuary, NH (2011)

The eastern oyster (Crassostrea virginica) in New Hampshire’s Great Bay Estuary has declined in the past decades, with local populations at very low densities due primarily to disease, excessive siltation, and past over-harvest. The loss of filtering oysters results in diminished ecological benefits for water quality, nitrogen control, and other services that healthy oyster populations provide. In support of regional management objectives to restore millions of oysters to the estuary, the Nature Conservancy (TNC) and the University of New Hampshire (UNH) piloted and scaled-up methods to successfully rebuild oyster reefs. Based on pilot results in 2009, we developed a technique using a thin layer of recycled clamshell “planted” over silted channel bottom as a hard substrate foundation to recruit natural spawn, supplemented with hatchery-raised and volunteer-grown seed “spat”. In 2010, a full acre reef was constructed and seeded at the mouth of the Oyster River in Durham, producing a one-year standing stock of \u3e200K oysters. In 2011, restoration efforts were scaled up significantly, led by support from the Piscataqua Region Estuaries Partnership (PREP), with two acres of reef construction at the mouth of the Lamprey River (Newmarket NH). In June 2011, approximately 200 yd3 of seasoned surf clam shell was deployed at the site for total shell coverage of 80,000 ft2 (7,432 m2). Fall monitoring results showed that an estimated 58K oyster spat were recruited to the reef (19.5 spat/m2). Supplements from UNH remote setting operations added 428K spat to the reef areas, plus an additional 17K spat were raised by community volunteers. By fall 2011, the completed reefs achieved a standing stock of \u3e500K oysters. In addition, another half-acre restoration site was built nearby with farmer support. Collectively, our efforts demonstrate significant progress towards a regional goal of 20 acres of oyster reef restored by 2020, and position us for further expansion of restoration work going forward

Restoring Oyster Reefs in Great Bay Estuary, NH 2012 Annual Program Report

The eastern oyster (Crassostrea virginica) in New Hampshire’s Great Bay Estuary has declined in the past decades, with local populations reduced due primarily to disease, excessive siltation, and past over-harvest. The loss of filtering oysters results in diminished ecological benefits for water quality, nitrogen control, and other services that healthy oyster populations provide. In support of management objectives to restore oyster populations, The Nature Conservancy (TNC) and the University of New Hampshire (UNH) have combined for a fourth consecutive year of scaled-up methods to rebuild reefs and oyster populations. Since 2009, we have “planted” dried shell, primarily surf-clam and oyster mix, on channel bottom as a hard substrate foundation to recruit spawn from nearby native populations. Constructed areas are amended with laboratory raised and volunteer-grown “spat-on-shell” from remotely set larvae to supplement recruitment. In 2012, despite limited funding, we successfully constructed and seeded two new acres of reef adjacent to native oysters in the mouth of Squamscott River, Newmarket. Results were somewhat below target for shell cover and live oyster density but natural recruitment was strong and encouraging for future reef development. Overall, we restored about a quarter of a million new oysters to the estuary. Community engagement, particularly through the volunteer Oyster Conservationist program, reached an all-time high with thirty-nine families participating in direct restoration activities and another twenty-three volunteers assisting in various project tasks

Scaling-Up: A Fifth Year of Restoring Oyster Reefs in Great Bay Estuary, NH 2013 Annual Program Report

The eastern oyster (Crassostrea virginica) in New Hampshire’s Great Bay Estuary has declined in the past decades, with local populations reduced due primarily to disease, excessive siltation, and past over-harvest. The loss of filtering oysters results in diminished ecological benefits for water quality, nitrogen control, and other services that healthy oyster populations provide. In support of management objectives to restore oyster populations, The Nature Conservancy (TNC) and the University of New Hampshire (UNH) have combined for a fifth consecutive year of scaled-up methods to rebuild oyster reefs and populations. Since 2009, we have “planted” seasoned shell, primarily surf-clam and oyster mix, on channel bottom as a hard substrate foundation to recruit spawn from nearby native populations. Constructed areas are amended to supplement recruitment with laboratory-raised and volunteer-grown “spat-on-shell” from remotely set larvae. Following four consecutive years of experience and adaptation, 2013 was a year of unprecedented effort and conservation outcomes. We successfully constructed and seeded five new acres of reef adjacent to native oysters in the Piscataqua River in Dover (1.5 acres) and in the Lamprey River in Newmarket (3.5 acres). Notably, we employed a new shell deployment method to achieve large-scale reef construction. Restoration efforts were greatly enhanced by excellent remote set success and outstanding natural recruitment, resulting in over 2M oysters. In addition, community engagement through the volunteer Oyster Conservationist program reached another all-time high with fifty families producing our largest oyster stock ever for restoration. Over the past five years, our efforts have added over 13 acres and 3M oysters to the ecosystem, increasing native Great Bay Estuary oyster populations by about 10%

Shellfish Spotlight: 2008

Each year Granite State shellfishers search shallow briny waters in search of delicious mussels, clams, or oysters for the dinner table. Those who are skilled often are rewarded with full buckets, but few shellfishers realize that good harvests in New Hampshire’s Seacoast owe much to activities occurring far upstream. The quality of the water and amount of available nutrients that sustain a clam or oyster is directly related to the condition of the rivers and streams that drain the land. The Hampton-Seabrook Estuary is fed by approximately 46 square miles of surrounding land. An even larger system, the Piscataqua River Estuary that includes Great Bay, is supplied by a watershed that is 1,023 square miles. Development within the coastal watershed area has profound impacts on the amount of contaminants flowing to the sea. Sediment washed from roadways and bare soil flows downstream and collects in the estuary where it smothers shellfish beds in extreme cases. Nutrients, primarily nitrogen, are contributed by wastewater treatment plants, septic systems, and land use activities such as lawn fertilizing. Excessive nutrients threaten the ecological balance of the estuaries and thus the survival of shellfish populations. Finally, bacteria from failing septic systems, pet waste, or damaged sewer systems create a human health hazard in estuarine waters. Because shellfish filter great amounts of water to take in food and oxygen, they absorb contaminants from the water that accumulate in their flesh. Therefore, a watershed that flushes large amounts of contaminants downstream will deliver many of these contaminants to shellfish and reduce their numbers or often make them unsafe to eat. It is this close relationship between coastal watershed function and shellfish health that caused the New Hampshire Estuaries Project (NHEP), and many partnering agencies, to monitor shellfish in New Hampshire and make their restoration and maintenance a priority. The NHEP Manage- ment Plan includes many strategies that improve water quality throughout the watershed that will in turn improve shellfish populations and open more harvesting areas

Expressed sequence tag analysis of genes expressed during development of the tropical abalone Haliotis asinina

The tropical abalone. Haliotis asinina. is,in ideal species to investigate the molecular mechanisms that control development. growth, reproduction and shell formation in all cultured haliotids. Here we describe the analysis of 232 expressed sequence tags (EST) obtained front a developmental H. asinina cDNA library intended for future microarray studies. From this data set we identified 183 unique gene Clusters. Of these, 90 clusters showed significant homology with sequences lodged in GenBank, ranging in function from general housekeeping to signal transduction, gene regulation and cell-cell communication. Seventy-one clusters possessed completely novel ORFs greater than 50 codons in length, highlighting the paucity of sequence data from molluscs and other lophotrochozoans. This study of developmental gene expression in H. asinina provides the foundation for further detailed analyses of abalone growth, development and reproduction

A Restoration Suitability Index Model for the Eastern Oyster (Crassostrea virginica) in the Mission-Aransas Estuary, TX, USA

Oyster reefs are one of the most threatened marine habitats on earth, with habitat loss resulting from water quality degradation, coastal development, destructive fishing practices, overfishing, and storm impacts. For successful and sustainable oyster reef restoration efforts, it is necessary to choose sites that support long-term growth and survival of oysters. Selection of suitable sites is critically important as it can greatly influence mortality factors and may largely determine the ultimate success of the restoration project. The application of Geographic Information Systems (GIS) provides an effective methodology for identifying suitable sites for oyster reef restoration and removes much of the uncertainty involved in the sometimes trial and error selection process. This approach also provides an objective and quantitative tool for planning future oyster reef restoration efforts. The aim of this study was to develop a restoration suitability index model and reef quality index model to characterize locations based on their potential for successful reef restoration within the Mission-Aransas Estuary, Texas, USA. The restoration suitability index model focuses on salinity, temperature, turbidity, dissolved oxygen, and depth, while the reef quality index model focuses on abundance of live oysters, dead shell, and spat. Size-specific Perkinsus marinus infection levels were mapped to illustrate general disease trends. This application was effective in identifying suitable sites for oyster reef restoration, is flexible in its use, and provides a mechanism for considering alternative approaches. The end product is a practical decision-support tool that can be used by coastal resource managers to improve oyster restoration efforts. As oyster reef restoration activities continue at small and large-scales, site selection criteria are critical for assisting stakeholders and managers and for maximizing long-term sustainability of oyster resources