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Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
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Showing 1 to 20 of 94 for “"freshwater mussels"”.
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Freshwater Mussels as Biofilters
Freshwater mussels (Bivalvia: Unionidae) are filter feeders, removing phytoplankton and other suspended particulate matter from the water. The removal of suspended matter from water is often considered desirable, in order to reduce algal blooms and in the treatment of drinking water. This thesis …
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Flatworm Predation on Juvenile Freshwater Mussels
… predominantly benthic species, feeds on juvenile freshwater mussels in fish hatcheries and mussel culture facilities. Laboratory experiments were performed to assess the predation rate of M. tuba on newly transformed juveniles of plain pocketbook mussel, Lampsilis cardium. Predation rate at 20°C …
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Byssus Production in Freshwater Mussels (Bivalvia: Unionoidea)
Freshwater mussels (Order Unionoida) are a widespread and ecologically significant group of bivalve mollusks that are particularly diverse in North American rivers. Mussels are patchily distributed, but can be very abundant in suitable habitat and dense multispecies aggregations known as "mussel …
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Crayfish Predation on Juvenile Freshwater Mussels (Bivalvia: Unionidae)
North American native freshwater mussels are among the most endangered faunal groups in the world. Juvenile mussels are very small and potentially vulnerable to a wide variety of predators, including crayfish. This study examines predation by a native crayfish, Orconectes neglectus on juvenile …
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Parasites in freshwater mussels: community ecology and conservation
… unexplored system: the ecosystem-engineering freshwater mussels (Unionida) and their macroparasites. As such, this thesis has three broad aims: to characterise knowledge to date on unionid mussel parasite communities and develop tools to further knowledge in this area; to analyse the drivers …
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Population trends and ecological community interactions of freshwater mussels
Freshwater mussels (order Unionida) are a globally widespread taxon which have been described as ecosystem engineers due to their capacity to modify freshwater habitats and facilitate other taxa, with effects on wider biodiversity. At the same time, freshwater mussels rank among the most threatened …
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Development of a diet for rearing juvenile freshwater mussels
Over 100 species of freshwater mussels (Unionidae) are endangered or threatened in the United States, and another dozen species support a declining commercial harvest of shells for the cultured pearl industry in Asia. Because of these Significant declines in abundance, a study was undertaken to …
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Immunological responses of fishes to glochidia of freshwater mussels
… glochidia and post-infestation juvenile mussels are antigenically different.
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Copper exposure of freshwater mussels (Anodonta anatina): Some physiological effects
… the tendency to increase in its concentration in freshwater ecosystems over natural levels, due to industrial and other anthropogenic sources. In water, copper can exist in dissolved form or associated with suspended food particles. Freshwater mussels living at the interface of the free-flowing …
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Host Specificity of Freshwater Mussels: a Critical Factor in Conservation
Freshwater mussels have a unique life cycle in which they parasitize a fish host during their larval stage. While fish hosts of many mussel species have been identified, little is known of variation in host-specificity among populations, within species. I investigated host compatibility in two …
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Development of an Algal Diet for Rearing Juvenile Freshwater Mussels (Unionidae)
… days old, 50-53 days old, and 3-6 years old. The mussels were fed an algal diet consisting of Scenedesmus quadricauda (22.3 - 44.5 μm), Nannochloropsis oculata (2.8 – 8.1 μm), and Selenastrum capricornutum (3.6 – 8.5 μm) in equal cell densities. The change in relative abundance of each algal …
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Evaluation of Diet, Gametogenesis, and Hermaphroditism in Freshwater Mussels (Bivalvia: Unionidae)
… the effects of different algal diets on freshwater mussels, tissues of Elliptio complanata were sampled for physiological, somatic, and gametogenic condition from August 1999 to May 2000. Treatments included mussels fed Scenedesmus quadricauda (S), Neochloris oleoabundans (N), a no feed …
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Freshwater Mussels Vary in Substrate Preference and Mobility in Pairwise Behavioral Experiments
Freshwater mussels are a highly imperiled group of organisms that are sensitive to environmental stressors such as drought, flooding events, and global warming. While most mussels are considered to have broad sediment tolerances, some species are micro-habitat specialists. Mussel mobility can vary …
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The Effect of Flow on Burrowing in Juvenile Freshwater Mussels (Bivalvia, Unionidae)
… is a significant factor in the survival of freshwater mussels; it helps to prevent dislodgement from the sediment, and it reduces the risk of predation. In this study the burial time and orientation of juvenile mussels were tested in response to flow and substrate in a recirculating flow …
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Resolving the evolutionary history of multiple groups of freshwater mussels (Bivalvia : Unionidae).
Freshwater mussels are a group of aquatic invertebrates comprised of approximately one thousand species worldwide, and the greatest diversity of freshwater mussels lies within North America with at least three hundred species. The high level of biodiversity in this group is strongly shaped by a …
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Sensitivity of early life stages of freshwater mussels (Bivalvia: Unionidae) to copper
Four life stages of freshwater mussels were tested for their sensitivity to copper and a metal-containing effluent. This permitted an assessment of the variability in sensitivity among the life stages in order to identify those stages most threatened in the wild from copper exposure. Glochidia, …
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Approaches for assessing toxicity of selected contaminants to freshwater mussels (Bivalvia: Unionidae)
… results suggest that early life stages of freshwater mussels are sensitivity to toxicants. However, toxicological databases for unionids are rather limited because standard test methods are yet developed, and no published studies report endpoints for chronic test that are > 9 days. The …
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Assessing Freshwater Mussels (Bivalvia: Unionidae) in South Dakota and Identifying Drivers of Assemblage Variation
<p>Native freshwater mussels (Family: Unionidae) are among the most threatened groups of freshwater fauna on Earth. Approximately 35 species have gone extinct since the 1900s and 72% of remaining species are considered endangered, threatened, or species of special concern. Unionid research can …
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The Effect of Dieoffs of Asian Clams (Corbicula fluminea) on Native Freshwater Mussels (Unionidae)
… is a great deal of concern about the declining freshwater mussel fauna of North America. Although deteriorating water quality and habitat degradation may account for much of the decline, it has been suggested that the exotic Asian clam, Corbicula fluminea, may be having an effect on native …
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