Does anyone know of articles on habitat restoration projects using blue mussels (Mytilus edulis) as fish habitat?

This is what I have regarding mussels and environment. I don’t know whether you already have all these quotations.

Alvaro

EFFECTS OF SHELLFISH CULTURE ON WATER QUALITY, NUTRIENT CYCLING OR NUTRIENT DYNAMICS (e.g., NITROGEN, SULFUR, PHOSPHOROUS, PSEUDOFECES)

Brylinsky, M. 1989. Development of a simulation model of a cultured mussel (Mytilus edulis) population: Potential and limitations. Journal of Shellfish Research. 8(2):470.

In an attempt to elucidate the complex relationships existing between the physical and biological processes that control the growth, spawning and mortality of cultured mussels, a computer simulation model was developed. The model is driven by temperature and particulate inorganic and organic matter concentration, and outputs shell and meat growth rates and spawning times. The model has been validated against several independent data sets and appears to have considerable predictive ability. The potentials and limitations of the model will be discussed in terms of its usefulness for addressing problems such as site selection, carrying capacity, summer mortality and the environmental impact of mussel culture.

Keywords: growth, simulation, Mytilus, edulismortality, mussel, culture

Cheney, D.P., A.D. Suhrbier, and A.E. Christy, et al. 2003. Mussel growth and food utilization in relation to water column conditions on raft systems in Puget Sound, Washington. Journal of Shellfish Research, 22(1):324.Environmental

Suspended mussel and oyster culture on the U.S. west coast is predicted to increase significantly in coming years. Description of the changes associated with the culture of these crops is essential for the siting and evaluation of new culture facilities and in improving yield and production of existing facilities. This research had three general objectives: 1) to assess at large-scale farm sites, mussel growth and yield against a suite of measured physical, chemical and biological variables; 2) to compare the same suite of variables with measurements of mussel feeding and biodeposit production; and 3) to utilize available nutrient and yield models to estimate potential mussel carrying capacity in the farming area. During a two year period (2001-03), multiple observations were made of water currents, water chemistry, phytoplankton, mussel growth, seston removal and absorption, fouling, and fish utilization at commercial mussel raft culture sites in Totten Inlet and Penn Cove, Washington. Although parameters, such as water currents and phytoplankton abundance varied markedly inside and outside the raft units and under different tidal regimes, these effects were localized and did not correlate with mussel growth. This research is supported by a Sea Grant National Marine Aquaculture Initiative grant.

Keywords: Marine aquaculture, Mussel culture, Raft culture, Growth rate, Yield, Food availability, Phytoplankton, Physicochemical properties, Current velocity, Nursery grounds, Mytilus, INE, USA, Washington, Puget Sound.

Dame, R., N. Dankers, T. Prins, H. Jongsma, and A. Smaal. 1991. The influence of mussel beds on nutrients in the western Wadden Sea and eastern Scheldt estuaries. Estuaries 14: 130-138.

The uptake and release of materials by intertidal mussel beds were directly measured in two cultivated Dutch estuaries. Generally, chlorophyll a, seston, and particulate organic carbon were taken up, while ammonium, orthophosphate, and silicate were released. The observed rates were higher than values computed from organismic observations and similar to those observed for intertidal oyster reefs in South Carolina. Specific estuarine material turnover rates varied from 1week to 38 weeks when calculated with mussel bed fluxes. The fastest turnover rates were for chlorophyll a and ammonium. These results support the idea that dense assemblages of bivalves are major components in the recycling of nutrients in estuaries.

Dolmer, P. and R.P. Frandsen. 2002. Evaluation of the Danish mussel fishery: suggestions for an ecosystem management approach. Helgoland Marine Research. Vol. 56, no. 1, pp. 13-20. IS: ISSN 1438-387X.

In Limfjorden, Denmark, an extensive mussel fishery exploits the wild stocks of Mytilus edulis with annual landings of 80,000-100,000 t of mussels. During the last 10 years the impact of mussel dredging on the ecosystem has been studied, including the effect of resuspension of sediment and nutrients and the impoverishment of in- and epi-fauna assemblages. Furthermore, dredging changes the physical structure and complexity of the seabed which affects mussel growth and interactions among zoo benthic species. The blue mussel constitutes the dominant fraction of the zoobenthic suspension feeders, and is important for the transport of material and energy from the pelagic to benthic systems and the control of phytoplankton biomass. In order to evaluate the impact on clearance capacity of a reduction in mussel densities due to mussel dredging, mussel filtration activity measured in situ has been related to the mixing of the water column and the amount of near-bed phytoplankton. Fishery practice for mussel dredging in Limfjorden is discussed in relation to its known impact on the ecosystem and the ecological role of the mussels, and modifications towards an ecosystem management approach and a more sustainable fishery are suggested. The suggested modifications include: a fishery practice where the mussel beds are thinned out when the mussels have attained good quality, and a transplantation practice of mussels from areas with a high mortality to areas with a high growth rate. Both practices intensify the production in a certain area, leaving other areas open for alternative production or for permanent closure for the benefit of the benthic flora and fauna. In addition, other shellfish species represent interesting new resources for fishing or aquaculture.

Habitat restoration, such as the relaying of mussel shells from the mussel industry, is another important management tool that should be included in an ecosystem management approach of the mussel fishery.

Grant, J.; A. Hatcher, D.B. Scott, P. Pocklington, C.T. Schafer, and G.V. Winters. 1995. A multidisciplinary approach to evaluating impacts of shellfish aquaculture on benthic communities. Department of Oceanography, Dalhousie University, Halifax, NS B3H 4J1, Canada, Estuaries. Vol. 18, no. 1A, pp. 124-144. IS: ISSN 0160-8347.

The impact of suspended mussel culture (Mytilus edulis, M. trossulus) on the benthos of a small Nova Scotia cove (7 m depth) was assessed using methods involving both benthic metabolism and community structure. Cluster analysis of macrofauna usually provided a clear separation between sites. Since the construction of a causeway (1968), foraminifera species composition showed a temporal response to temperature changes in the cove by shifting toward calcareous species, but assemblages downcore showed little or no relationship to aquaculture impacts. Although there is a shift toward anaerobic metabolism at the mussel lines, the impact of mussels falling to the sediments was more noticeable in benthic community structure than was any impact due to organic sedimentation or hypoxia. In general the impact of aquaculture on the benthos appeared to be minor. Further assessment of these consequences may mandate both taxonomic and energetic approaches to impact assessment.Environmental Keywords: mussel culture; zoobenthos; environmental impact; ecosystem disturbance; community composition; aquaculture; environmental effects; benthos; effluents; Mytilus; mussels; Mytilus; ANW, Canada, Nova Scotia; Canada, Nova Scotia.

Holmer, M., N. Ahrensberg, and N. P. Jorgensen. 2003. Impacts of mussel dredging on sediment phosphorus dynamics in a eutrophic Danish fjord. Chemistry and Ecology. 1Dame, R., N. Dankers, T. Prins, H. Jongsma, and A. Smaal. 1991. The influence of mussel beds on nutrients in the western Wadden Sea and eastern Scheldt estuaries. Estuaries 14: 130-138.

Dankers, N., and D.R. Zuidema. 1995. The role of the mussel (Mytilus edulis L.) and mussel culture in the Dutch Wadden Sea. Estuaries. 18(1):71-80.

Mussel populations (Mytilus edulis) in the Dutch Wadden Sea (intertidal mussel beds, subtidal beds and culture plots), the culture methods, the extent of mussel culture, and the ecology of the mussel are described. Mussels filter suspended matter from the water column and deposit it as feces and pseudofeces. Mussel beds consume large amounts of phytoplankton and speed up the cycle of production and breakdown of organic matter. There are indications that the consumption of phytoplankton can lead to food shortage for several animal groups. Mussels serve as an important food source for a wide range of organisms (e. g., starfish, eider ducks, and oystercatchers). Because mussel culture increased the mussel biomass in the Dutch Wadden Sea, the impact also increased. The most obvious impact of the culture is the dredging of seed mussels. Overexploitation of intertidal mussel and cockle beds and bad spatfall of both mussels and cockles since 1988 had a negative impact on bird populations. The extent of positive and negative aspects of mussel culture depends on natural and human influences.

Keywords: mussel, culture, Mytilus, edulis species, culture, Wadden Sea..

Holmer, M., N. Ahrensberg, and N. P. Jorgensen. 2003. Impacts of mussel dredging on sediment phosphorus dynamics in a eutrophic Danish fjord. Chemistry and Ecology. 19: 343–361.

Effects of mussel dredging on sediment metabolism (oxygen uptake and sulfate reduction rates) and phosphorus dynamics (flux across sediment-water interface and sequential extraction) were examined in Limfjorden (Denmark) during spring (May) and summer (August). Sediment samples were taken during mussel dredging and in addition an experimental simulation of the dredging was performed to investigate short-term changes in phosphorus (P) dynamics. Iron-bound P was reduced by up to 2=3 in the surface layer in the dredging track (from 31 to 8 mmol Pm_2), whereas the dissolved P-pools and less reactive particulate pools were not affected by dredging. Sediment oxygen consumption was enhanced immediately after dredging, but returned to the initial level after 4 days (20–40 mmolm_2 d_1). The enhanced consumption was attributed to reoxidation of reduced compounds released during dredging. Sulfate reduction rates were high in the area (13–15 mmolm_2 d_1) and sulfides competed with P for oxidized iron resulting in low iron-bound pools in the area (picoplankton, while picophytoplankton, likewise phytoplankton, did not display differences among fish or mussel farms and control site. From the analysis of the different microbial components, it is possible to conclude that the impact of fish farms is evident only for the heterotrophic components. The comparative analysis of the mussel biodeposition and fish-farm impact revealed that mussel farms induced a considerably lower disturbance, apparently limited to an increased density and biomass of microbial assemblages beneath the mussel cultures.

Lindahl, O., R. Hart, and B. Hernroth, et al. 2005. Improving Marine Water Quality by Mussel Farming: A Profitable Solution for Swedish Society. Ambio. 34(2):131-138.

Eutrophication of coastal waters is a serious environmental problem with high costs for society globally. In eastern Skagerrak, reductions in eutrophication are planned through reduction of nitrogen inputs, but it is unclear how this can be achieved. One possible method is the cultivation of filter-feeding organisms, such as blue mussels, which remove nitrogen while generating seafood, fodder and agricultural fertilizer, thus recycling nutrients from sea to land.

The expected effect of mussel farming on nitrogen cycling was modeled for the Gullmar Fjord on the Swedish west coast and it is shown that the net transport of nitrogen (sum of dissolved and particulate) at the fjord mouth was reduced by 20%. Existing commercial mussel farms already perform this service for free, but the benefits to society could be far greater. We suggest that rather than paying mussel farmers for their work that nutrient trading systems are introduced to improve coastal waters. In this context an alternative to nitrogen reduction in the sewage treatment plant in Lysekil community through mussel farming is presented. Accumulation of bio-toxins has been identified as the largest impediment to further expansion of commercial mussel farming in Sweden, but the problem seems to be manageable through new techniques and management strategies. On the basis of existing and potential regulations and payments, possible win-win solutions are suggested.

Mwangi, S.N. 1994. The influence of bivalve filter feeders on bacteria populations and seston in Gazi Bay and Wadden Sea. 92.

This study investigated the effect that bivalve filter feeders had on the bacteria and seston concentration of the water that flowed through their beds, the tidal influence on food availability for the bivalves and seasonal changes of bacteria and seston concentrations. The study was carried out in an oyster culture plot in Gazi Bay, Kenya and in the Dutch Wadden Sea where intensive mussel culture is carried out. On a few occasions, the oysters in Gazi were observed to reduce the bacteria biovolume and thus the biomass, reduce chlorophyll-a concentration in the water and take up the easily degradable organic material. Bacteria and the total seston concentration in the water varied with the tide thus influencing food availability for the oysters.

Resuspension during both flood and ebb tides resulted in a general increase in bacteria abundance and biomass, dissolved oxygen, suspended matter, easily degradable organic material, POC and chlorophyll-a. In the Wadden Sea, the water overlying mussel beds was observed to have a high bacteria abundance but of low biovolume thus low total biomass in autumn. There were more indications of enhanced bacteria abundance than bacteriovory. Phytoplankton uptake was not clearly observed probably due to the prevailing hydrodynamic conditions. The total microbial biomass was not strongly influenced by the tide and bacteria contributed the highest proportion of the biomass. Respiratory activity was not high and was also not strongly influenced by the tide. In spring, increase in bacteria biomass through increased biovolumes was observed with indications of bacteriovory. A reduction of POC and chlorophyll-a in the water overlying the mussel beds was observed suggesting the uptake of organic matter and phytoplankton. There were high tidal fluctuations of POC, chlorophyll-a and bacteria abundance and biomass. Bacteria contributed less to the total microbial biomass in spring.

Keywords: Seston, Intensive, culture, Oyster, culture, Mussel, culture, Tidal constituents, Phytoplankton, Resuspension, Dissolved, oxygen, hlorophylls, Particulate ,organic, carbon, Filter, feeders, Ostreidae ,Mytilidae ,ISW, Kenya, Coast, Gazi Bay, Netherlands, Wadden Sea, Bacteria, Bivalves, Clams, Mussels, Bivalvia.

Nizzoli, D., D. T. Welsh, M. Bartoli, and P. Viaroli. 2005. Impacts of mussel (Mytilus galloprovincialis) farming on oxygen consumption and nutrient recycling in a eutrophic coastal lagoon. Hydrobiologia. 550(1):183-198.

Fluxes of oxygen, nitrogen and phosphorus were determined in two areas of the Sacca di Goro lagoon, at a site influenced by the farming of the mussel Mytilus galloprovincialis and a control site. Mussel farming induced intense biodeposition of organic matter to the underlying sediments, which stimulated sediment oxygen demand, and inorganic nitrogen and phosphorus regeneration rates compared to the nearby control station. Overall benthic fluxes (–11.4 ± 6.5 mmol O 2 m−2 h−1; 1.59 ± 0.47 mmol NH 4+ m−2 h−1 and 94 ± 42 μmol PO 43− m−2 h−1) at the mussel farm are amongst the highest ever recorded for an aquaculture impacted area and question the belief that farming of filter-feeding bivalves has inherently lower impacts than finfish farming. In situ incubations of intact mussel ropes demonstrated that the mussel rope community was an enormous sink for oxygen and particulate organic matter, and an equally large source of dissolved inorganic nitrogen and phosphate to the water column. Overall, a one meter square area of mussel farm (mussel ropes and underlying sediment) was estimated to have an oxygen demand of 46.8 mmol m2 h−1 and to regenerate inorganic nitrogen and phosphorus at rates of 8.5 and 0.3 mmol m2 h−1, with the mussel ropes accounting for between 70 and more than 90% of the overall oxygen and nutrient fluxes. Even taking into account that within the farmed area of the Sacca di Goro lagoon, there are 15–20 m−2 of open water for each one covered with mussel ropes, the mussel ropes would account for a large and often dominant part of overall oxygen and nutrient fluxes. These results demonstrate that it is essential to take into account the activity of the cultivated organisms and their epiphytic community when assessing the impacts of shellfish farming. Overall, whilst grazing by the mussel rope community could act as a top-down control on the phytoplankton, most of the ingested organic matter is rapidly recycled to the water column as inorganic nutrients, which would be expected to stimulate phytoplankton growth.

Consequently, the net effect of the mussel farming on phytoplankton dynamics may be to increase phytoplankton turnover and overall production, rather than to limit phytoplankton biomass.

Keywords: aquaculture, impacts, biodeposition, benthic, metabolism, ropes, metabolism, nutrient, cycles, species, culture.

Richard, L. 2004. Balancing marine aquaculture inputs and extraction: Combined culture of finfish and bivalve molluscs in the open ocean. Bulletin of Fisheries Research Agency (Japan). no. Sup. 1, pp. 51-58. IS: ISSN 1346-9894.

Enrichment of the water column with dissolved nutrients and of bottom sediments with organic matter as a result of culturing finfish in sea cages have been identified as real and potential environmental impacts of fish culture. While severe impacts have been documented in shallow, poorly flushed waters, proper siting of sea cage operations generally results in only minor localized impacts to the benthic community on the sea floor directly beneath the cages.

None the less, the perception of environmental groups and regulatory agencies in the U.S.A. that fish waste and uneaten feed will impact the marine environment regardless of siting has affected the expansion of existing sites and the establishment of new sites. In order for the industry to expand to meet the growing demand for seafood, measures to mitigate these impacts must be taken. One possible solution is to balance inputs of feed with extraction of biomass of organisms such as marine plants and bivalve molluscs that do not require external feed application. In 1999, the University of New Hampshire established the Open Ocean Aquaculture Demonstration Project. Funded by the National Oceanic and Atmospheric Administration, the project was designed to provide a commercial scale demonstration and research site for open ocean aquaculture in the northeast U.S.A. The project is an integrated, multi-disciplinary, regional effort that includes biology, oceanography, engineering, sociology, economics, technology transfer, and education. While the development of technologies for finfish and shellfish production in offshore environments is central to the mission of the project, demonstration of the environmental sustainability of open sea culture is critical to the social acceptance of industry development. Since 1999, the project has produced harvests of several species of finfish using submersible sea cages and six crops of molluscan shellfish (primarily blue mussels) using submerged longlines in close proximity to the sea cages. While not considered true polyculture, the harvest of the filter feeding bivalve molluscs represents a net removal of nitrogen, carbon and phosphorus that can be used in mass balance to offset the addition of these nutrients from finfish feeding. In this paper, data the potential for balancing inputs associated with feed application and fish wastes with extraction of fish and bivalve biomass will be examined.

Smaal, A., M. van Stralen and E. Schuiling. 2001. The interaction between shellfish culture and ecosystem processes. Canadian Journal of Fisheries and Aquatic Sciences. 58(5):991-1002.

The carrying capacity of the Oosterschelde ecosystem for the production of mussels (Mytilus edulis) was evaluated before and after completion of a large-scale coastal engineering project in 1987. This project caused hydrodynamic and water-quality changes; hence, phytoplankton-species composition change and phytoplankton turnover increased but primary production remained the same. In the prebarrier period (1980-1986), condition of mussels showed a significant negative correlation with the annual shellfish standing stock and a significant positive correlation with the annual primary production. The system was exploited at maximum capacity. In the postbarrier period (1987-1997), the significant correlation between mussel condition and primary production remained, but there was no longer a negative correlation between standing stock and condition. This indicates overstocking, but yields were maintained. This was explained by 1) feedbacks of the mussels in the Oosterschelde ecosystem -through their large filtration and nitrogen-regeneration capacity, increased phytoplankton turnover was induced; and 2) adaptation to new conditions by the shellfish farmers in their management of mussel stocks. It was concluded that feedbacks by filter feeders and farmers have to be addressed in estimating the exploitation capacity of ecosystems.

Keywords: Mussel, culture, Carrying, capacity, Primary, production, Dams, Storm, surge, barriers, Environmental impact, Ecological balance, Mytilus, edulis, ANE, Netherlands, Zeeland, Oosterschelde.

van der Veer, H.W. 1989. Eutrophication and Mussel Culture in the Western Dutch Wadden Sea: Impact on the Benthic Ecosystem; A Hypothesis. Helgolaender Meeresuntersuchungen HEMEDC. Vol. 43, No. 3/4, p 517-527, 6 fig, 1 tab, 25 ref.

Since 1950, two large-scale changes have taken place in the western Dutch Wadden Sea, namely the eutrophication of the area and the introduction of an extensive mussel culture. Although eutrophication in the fresh waters started already around 1950, nutrient concentrations in the western Wadden Sea remained fairly constant until about 1970, due to the retention of nutrients in Lake Ijssel, the main source. From 1970-1980 concentrations increased strongly, and during the last years the situation has stabilized. Mussel culture was introduced in 1950 and expanded during the next decade to an area of 70 sq km, all situated in the sublittoral area. From 1960 the area of mussel culture remained about constant with fluctuating yields of between 35 and 120 million kilograms of fresh weight. Due to a lack of data for the period until 1970 the impact of eutrophication and mussel culture cannot be assessed. From 1970 onwards an increased biomass and production of the macrofauna in the intertidal zone has been observed, which is attributed to eutrophication. The hypothesis is postulated that the introduction of mussel culture between 1950 and 1960 has resulted in an increased competition for food in the area, leading to a decreased stock of the macrofauna in the intertidal. Eutrophication from about 1970 onwards has improved the food conditions and as a result both the macrofauna in the intertidal and the mussel in the sublittoral area would have increased in biomass, allowing higher maximum yields of the mussel culture. Monitoring programs will be used to follow these trends in the near future and to check the above hypothesis in areas where it is decided to introduce or to intensify mussel culture. (Author 's abstract).

Keywords: Aquaculture; Benthic environment; Eutrophication; Mussels; Shellfish farming; The Netherlands; Wadden Sea; Water pollution effects; Water quality trends; Aquatic animals; Biomass; Competition; Ecosystems; History; Intertidal areas; Lake IJssel; Monitoring; Nutrient Concentrations.

EFFECTS OF SHELLFISH CULTURE ON HABITAT, VEGETATION, AND BENTHIC COMMUNITIES .

Arzul, G., M. Seguel, and A. Clement. 2001. Effect of marine animal excretions on differential growth of phytoplankton species. ICES J. Marine Science. 58(2):386-390.

Five phytoplankton species were cultivated in the presence of different marine animal excretions, and growth rates were compared. Growth of Chaetoceros gracilis was stimulated by excretion from the oyster (Crassostrea gigas) and inhibited by excretion from the sea bass (Dicentrarchus labrax). Growth of Heterosigma akashiwo was stimulated by excreta from the mussel (Mytilus chilensis) inhibited by excreta from sea bass and salmon (Salmo salar), and unaffected by oyster excretions. Growth of Gymnodinium mikimotoi was also inhibited by excreta from sea bass and unaffected by oyster excreta. Growth of Alexandrium catenella and A. minutum was not affected by animal excreta under our experimental conditions. The results indicate that the organic components of dissolved excreta were responsible for the observed effects: stimulators when excreted by shellfish, and inhibitors when excreted by finfish.

Beadman, H.A., M.J. Kaiser, M. Galanidi, R. Shucksmith, and R.I. Willows. 2004. Changes in species richness with stocking density of marine bivalves. Journal of Applied Ecology 41: 464-475.

Monocultures of mussels might alter the infaunal benthic community of adjacent and interstitial sediments through provision of a complex habitat, input of organically rich material and larval removal through filter feeding. At a site of commercial seabed mussel cultivation, we aimed to determine the effect of mussels on the infaunal community of an intertidal mudflat at different spatial scales and under different stocking strategies. 2. Mussels were laid at four different densities (2, 3, 5 and 7·5 kg m−2) on 400-m2 plots in a 4×4 Latin square. Benthic samples were collected within and 10–100 m distant from the cultivation area c. 7 months prior to and 18 months after seeding the plots with blue mussels. Benthic community characteristics were related to initial seeding density and to the actual surface area of mussels associated with each set of samples collected within replicate plots. 3. The presence of mussels significantly

changed the occurrence of some species of the infaunal community within the cultivated area. The infaunal communities supported fewer individuals and species than control treatments at all but the lowest mussel cover. 4. Species richness and the abundance of individuals per unit area also declined with increased area of mussel cover. The abundance of cirratulids and amphipods declined strongly with increasing mussel surface area. 5. Although the species composition and abundance of individual invertebrate species were altered by the presence of mussels, the distribution of individuals among species remained relatively unchanged. 6. Synthesis and applications. Overall, mussel beds changed the infaunal community, but the effects were localized (0–10 m) and not detectable at larger scales (10–100 m). Changes in benthic community composition could be reduced (but not eliminated) by lowering the stocking density of mussels to either 2 or 3 kg m−2. Given the small edge effects associated with cultivated mussel beds, the use of larger mussel beds would be preferable to many smaller mussel beds.

Keywords: community change, ecological impact, large-scale experiment, mussel cultivation, Mytilus edulis.

Bigford, T.E. 1998. Environmental Challenges Facing the Shellfishing Industry. NOAA Technical Report NMFS 128.157-163.

North American molluscan fisheries have been traditions since colonial times, but few specifics have been learned about effects of molluscan harvesting and culture on habitats. The relative effects of fishing gear on the seafloor remain an open question, except that government surveys on the benthos have shown that invertebrate populations are abundant and species compositions are diverse in areas where shellfish harvesting has taken place for at least 50 years. Effects of fishing gear are temporary, because even if numbers of associated invertebrates are slightly reduced they rebound when new generations settle. From an environmental viewpoint, oyster culture has modified habitats in a positive way. The presence of transplanted oysters on previously unplanted bottoms has provided much more surface area and a larger number of niches for various invertebrates to inhabit. The washing of silt off beds of shells to clean them for receiving sets of oyster spat injects silt into the water, but accounts for an inconsequential amount compared with the quantity lifted during every lengthy wind storm. Mussel culture using rafts has brought about large changes in the ecosystem of the Ria de Arousa in Spain. The infauna macrobenthos is depauperate, but the biomass of the megafauna has increased due to the food contribution provided by the mussels and their associated epifauna. Similar effects probably have taken place in areas of North America and Europe where mussels are grown on suspended lines. Consumer interest in shellfish products is growing and more shellfish will be grown by culture enterprises in the future. Facilities designed for shoreside construction are likely to elicit concerns about habitat degradation, particularly if the locations are underdeveloped. The shellfish industry needs to be wary of secondary impacts of construction and operation on water quality, but the industry can expect to be allied with other coastal enthusiasts arguing for water and sediment quality standards that will support shellfish culture.

Keywords: mussels, oysters, water quality, invertebrate, impacts, benthos, rafts, mussel, rafts, silt, sedimentation, ECOP.

Campbell, D.E., and C.R. Newell. 1998. MUSMOD copyright, a production model for bottom culture of the blue mussel, Mytilus edulis L. Journal of Experimental Marine Biology and Ecology. 219(1-2):171-203.

A mussel production model, MUSMOD copyright was developed to seed bottom culture lease sites in Maine to their carrying capacity. The process of model development is demonstrated with three models: (a) an initial conceptual model, (b) an aggregated model driven by the tidal exchange of food particles and (c) MUSMOD copyright, the final model driven by food supplied in the tidal flow of water across a site. The final model predicts mussel production using the concentrations of phytoplankton and detritus in the surface water, detritus quality, tidal current speed, water depth and temperature. Field measurements of several quantities (e.g., clearance, respiration, growth rates for shell and meat, food concentration gradient, and temporal feeding pattern) were obtained to evaluate and calibrate the final model. Model refinement using iterations of modeling and field work demonstrated the importance of food quantity and quality in explaining the observed patterns of mussel growth. Food quantity explained the first-order growth pattern, but it was necessary to account for the quality of the food to explain the second-order details of growth. Vertical mixing supplied the majority of new food particles, however, particles settling over the mussel bed during slack water accounted for 33% of the phytoplankton and 45% of the detritus entering the feeding layer from above. A sensitivity analysis of the effects of seed density on mussel growth using MUSMOD copyright identified the optimum carrying capacity for three Maine lease sites. Seeding mussels during the optimum time period Environmental Effects of (May to early July) resulted in the harvest of marketable mussels from 40 mm seed in 8 months for a high food year and in 13 months when the food supply was low. Characterizing the food supply using particulate organic matter, POM, alone was not sufficient to explain mussel growth in the detail necessary to answer many farm management questions.

Keywords: Mussel culture, Bottom culture, Seeding (aquaculture), Food availability, Suspended particulate matter, Particulate organic matter, Detritus, Particulate flux, models, growth, USA, Maine, aquaculture, Mytilus edulis, ANW, USA, Maine, phytoplankton, seed, density, food quality, Edible blue mussel.

Cayer, D., M. MacNeil, and A.G. Bagnall. 1999. Tunicate fouling in Nova Scotia Aquaculture: A new development. Journal of Shellfish Research. 18327.

A significant fouling problem with the tunicate Ciona intestinalis developed on a suspended blue mussel (Mytilus edulis) aquaculture site during the 1997 growing season. Ciona intestinalis has subsequently colonized several aquaculture sites at varying levels of intensity. The infestation has had a serious, negative impact on at least one farm and could potentially affect the economic viability of other operations. The Aquaculture Association of Nova Scotia

and the Nova Scotia Department of Fisheries and Aquaculture have been networking internationally, documenting the impacts of C. intestinalis on aquaculture production and searching for strategies to manage its effects. Information has been collected and contacts have been made around the world--a solution has not been found. Methods to manage this fouling problem will be species and site specific. Attempts to remove the tunicates have been cost prohibitive on a large scale. Farm management strategies must be developed as an economically viable solution. Part of this process involves studying the behaviour of C. intestinalis and its interactions with Nova Scotia operations. Cliona intestinalis biology and ecology are also being examined in an effort to prevent the further spread of these tunicates to previously unaffected aquaculture sites and to assist operations with implementing mitigative measures.

Keywords: Fouling organisms, Mussel culture, Pest-control, Marine aquaculture, Mytilus edulis, Ciona intestinalis, Ascidiacea, ANW, Canada, Nova Scotia, Ascidians, Sessile tunicates, Edible blue mussel.

Dankers, N., and D.R. Zuidema. 1995. The role of the mussel (Mytilus edulis L.) and mussel culture in the dutch Wadden Sea. Estuaries. 18(1):71-80.

Keywords: mussel culture, Mytilus edulis, species, culture, Wadden Sea.

DePauw, N., and J. -comps Joyce. 1991. A methodology for the assessment of the impact of suspended mussel culture on traditionally exploited areas in the Bay of L'Aiguillon (Atlantic coasts of France). Aquaculture and the Environment. (14):29.

Among the current techniques now available for the mussel culture, the traditional method of culturing the mussels on poles ("bouchots method") is still widely in use along the intertidal, sheltered areas of the French coasts. It resulted in a production averaging 55 000 tonnes for the last years. However, this country still imports roughly the same quantity, and there is a will for the development of this production. The implementation of long-lines in the Mediterranean Sea have already resulted in an annual production of 6 000 tonnes, and trials have been conducted in Atlantic sites, such as the Bay of l'Aiguillon. While this area produces 7 000 to 10 000 tonnes per year, large surfaces of deep water are unexploited, and may represent potential sites for suspended cultures. Therefore the preliminary tests being successful, a project of 200 long-lines of 200 metres has been designed, which may result within five years in a quantity of 5 000 tonnes of mussels. The questions are whether these mussels will compete for the available food, with the existing sites of production of mussels and oysters, within the same bay, and to assess the impact on the marine environment.

Keywords: analytic –techniques, environmental impact, mussel culture, off-bottom culture,

mathematical models, ecosystem, disturbance, France.

Dolmer, P., and R.P. Frandsen. 2002. Evaluation of the Danish mussel fishery: suggestions for an ecosystem management approach. Helgoland Marine Research. Vol. 56, no. 1, pp. 13-20. IS: ISSN 1438-387X.

column and the amount of near-bed phytoplankton. Fishery practice for mussel dredging in Limfjorden is discussed in relation to its known impact on the ecosystem and the ecological role of the mussels, and modifications towards an ecosystem management approach and a more sustainable fishery are suggested. The suggested modifications include: a fishery practice where the mussel beds are thinned out when the mussels have attained good quality, and a transplantation practice of mussels from areas with a high mortality to areas with a high growth rate. Both practices intensify the production in a certain area, leaving other areas open for alternative production or for permanent closure for the benefit of the benthic flora and fauna. In addition, other shellfish species represent interesting new resources for fishing or aquaculture. Environmental Effects of Habitat restoration, such as the relaying of mussel shells from the mussel industry, is another important management tool that should be included in an ecosystem management approach of the mussel fishery.

Geret, F., A. Jouan, V. Turpin, M. J. Bebianno, and R.P. Cosson. 2002. Influence of metal exposure on metallothionein synthesis and lipid peroxidation in two bivalve mollusks: the oyster (Crassostrea gigas) and the mussel (Mytilus edulis). Aquatic Living Resources. Vol. 15(no. 1):pp. 61-66.

The impact of metals (silver, cadmium, copper, mercury and zinc) on metallothionein (MT) and malondialdehyde (MDA) levels of the oyster (Crassostrea gigas) and the mussel (Mytilus edulis) was studied after 4 or 21 days of metal exposure. Moreover, total protein levels were determined. After 4 days of metal exposure, although C. gigas and M. edulis accumulated cadmium and mercury concentrations in the gills and digestive gland, no significant variation of total protein level was occurred. After 21 days of exposure, metals were bioaccumulated in the gills and the digestive gland of both mollusks. A decrease of total protein concentrations in the gills of oysters and the digestive gland of mussels and an increase on metallothionein concentrations in the gills of both mollusks were observed. An increase of MDA levels was noticed for the gills and the digestive gland of mussels exposed for 21 days to either cadmium, silver or mercury whereas a decrease of MDA levels was observed in the gills of the oysters exposed for the same time to the same metals. The levels of proteins, MDA and MT were metal, species or organ dependent.

Keywords: Metals, Proteins, Metallothioneins, Pollution effects, Lipids, Animal physiology,Crassostrea gigas, Mytilus edulis, Bivalvia malondialdehyde.

Heasman, K.G., G.C. Pitcher, C.D. McQuaid, and T. Hecht. 1998. Shellfish mariculture in the Benguela system: Raft culture of Mytilus galloprovincialis and the effect of rope spacing on food extraction, growth rate, production, and condition of mussels. Journal of Shellfish Research. 17(1):33-39.

Saldanha Bay forms part of the Benguela upwelling system. Here, the mussel Mytilus galloprovincialis is farmed by means of floating raft culture. The relationship between the food removed by mussels and the growth, condition, and production of mussels cultured on rafts with two different rope spacings was investigated. The dense culture of mussels on rafts is responsible for local limitation in food supply at the raft scale. Food depletion through a raft increased both with the age of the mussel ropes suspended from it and with decreased rope spacing and was a function of increased feeding and greater retardation of water exchange through rafts with higher mussel mass. Mussel growth rates in summer were 30% greater than in winter, and during summer, growth rates were a further 8% higher on rafts with increased rope spacing. The harvest of marketable mussels was 30% higher from ropes suspended at the increased spacing. Consequently, the harvest of mussels was 9% higher from rafts with the lower rope density.

Keywords: Marine aquaculture, Mussel culture, Aquaculture techniques, Off-bottom.

Inglis, G.J., and N. Gust. 2003. Potential indirect effects of shellfish culture on the reproductive success of benthic predators. Journal of Applied Ecology. Vol. 40, no. 6, pp. 1077-1089. Dec. IS: ISSN 0021-8901.

Environmental assessments of coastal aquaculture are concerned mostly with direct impacts on natural assemblages in the vicinity of shellfish or fin-fish farms. As the size and density of farmed sea space increases, there is greater potential for indirect effects on food webs beyond the immediate culture area. We investigated the potential indirect effects of long-line mussel Perna canaliculus farms on the demography of an important benthic predator, the sea star Coscinasterias muricata. Surveys beneath four active farms, an abandoned farm and three unfarmed areas of seabed in Pelorus Sound, New Zealand, described the direct effects of mussel culture on the distribution and abundance of sea stars and other benthic consumers. These data were used to calibrate a model that simulated the fertilization success of sea star populations in farmed and unfarmed areas of the bays. Deposits of living mussels and mussel shells covered up to 55% of the seafloor beneath farm sites, but were absent from soft sediments at unfarmed sites. Mean densities of sea stars were up to 39 times larger at active farm sites than in unfarmed areas and were correlated with the abundance of living mussels on the seafloor. Within individual farms, the distribution of sea stars was highly aggregated at small spatial scales, with most (63%) individuals occurring within 2 m of their nearest neighbor. In unfarmed areas, sea stars were widely dispersed (< 1 80 m super(-2)). 5. Our simulations indicate that, because of the extremely clumped distributions of sea stars, spawning individuals at farm sites would on average have substantially greater fertilization success (c. 90% of eggs) than those foraging in areas where farms are absent (80% of the dry weight being in the silt/clay (0.5 m

in diameter), adjacent to a clump, or in an open area without mussels (>1 m from any mussels).

Lastly, half of the pots were meshed to protect them from predation with flexible 6 mm meshing.

All pots were collected on September 28 super(th), 2000, and surviving clams were counted and measured. Survival was significantly lower in unprotected pots (P = 0.0001) than protected pots, and was also low underneath mussels. More interestingly, among unprotected clams not under mussels, survival tended to be better in the mussel bed than on the flat (adjacent, P = 0.0801; open, P = 0.0380). In terms of growth, final shell length was lowest underneath clumps of

mussels; among clams not underneath mussels (where survival was very low), growth tended to be better on the mudflat than in the mussel bed. This result was greater for unprotected clams (P less than or equal to 0.1437) than for protected clams (P greater than or equal to 0.2803), suggesting a possible interaction with predation. Thus, the presence of mussels has a mixture of effects upon clams, which need to be considered when contemplating removal.

Keywords: Density dependence, Clam culture, Marine molluscs, Competition, Filter feeders, Predation, Mytilus edulis, Mya arenaria, ANW, USA, Maine, Blue mussel, Softshell, clam.

Research about using a orange peel pectin derived agar in cultivating bacteria that is very versatile?

Why does my bone slice of a mouse femur have this huge gap between the bone marrow and the cortex of the bone?

Classification tables in logistic regression?

Is it possible to check that an antibody is successfully attaching to its antigen via mass spectrometry?

Why is there DNA in my mRNA sample after in vitro transcription?

What is the best measurement of organizational trust?

What are the best ways to measure stress - biometric or otherwise - for a leadership study?

Why pseudo second order kinetics model work for physisorption ?

How does sampling efficiency in droplet-based assays affect sensitivity?

Why the Thomas model work and the LDF doesn't ?

• What the possible Persistent Organic Pollutants and Heavy metals present in fluorspar, sediments, and water bodies around its mining area?

Handling Missing Data and Building a Predictive Model with Incomplete Information ?

Do interactions between biosphere, carbon cycle, & water cycle impact global warming & interaction between atmosphere & hydrosphere?

Is it true that $\det(V(A))$ may be only $\pm 1$, depending on $n$, for the last symmetric tridiagonal matrix $A$?

Weak DAPI staining after immunohistochemistry - how to improve?

The Curse of Evolution and Complexity?

How to Add Missing Water Molecules in Protein-Membrane Simulations?

Why is nonpoint source pollution potentially more harmful and difference between point and nonpoint sources of water pollution?

How do living organisms play a role in the water cycle and why is nonpoint source pollution potentially more harmful than point source pollution?

The use of data from PubChem for commercial purposes?