Mussel Ecology Research Articles

Seasonality of Gamete Production of Cyclonaias Species in Central Texas

Reproductive traits, which can impact population health, are important life-history characteristics for freshwater mussels. Little research has been done on the reproductive ecology of mussels, and crucial information is missing for many threatened and endangered species, especially in Texas. The objective of this study was to examine gamete production, parasitic infection rates, and sex ratios of two freshwater mussel species (Cyclonaias petrina and Cyclonaias pustulosa) in the Llano and San Saba rivers in central Texas. Gamete densities and egg diameters of C. petrina in the Llano River varied seasonally, with peak gamete densities occurring in December and February 2017 and being significantly lower from June through September 2017, while the relative abundance of the largest size classes of eggs was highest in February 2018. Few to no differences were detected in gamete production and egg diameter sizes for C. petrina between rivers. Cyclonaias pustulosa had significantly higher sperm densities and smaller egg diameters compared to C. petrina but exhibited similar egg densities in the San Saba River. There were no significant differences in gamete densities between rivers and no significant correlations between shell length and gamete density. Infection rates of parasitic trematodes varied from <1% to 14%, with the highest infection rates occurring in C. petrina in the San Saba River. Sex ratio of C. petrina was slightly skewed toward females in the Llano River and toward males in the San Saba River, with C. pustulosa having a 1:1 sex ratio in the San Saba River. The high percentage of samples without gametes suggests that the reproductive outputs of Cyclonaias appear to be more limited in the San Saba River due to several potential stressors. Further research will need to investigate the relative importance of the various stressors that affect the reproductive ecology of mussels and their persistence.

Amazonian freshwater mussel density: A useful indicator of macroinvertebrate assemblage and habitat quality

Mussels have important ecological functions in freshwater ecosystems, but populations are declining in many rivers worldwide. In the Amazon, which is undergoing widespread human-mediated alterations, information on mussel ecology is lacking. We investigated whether declines in mussel density, due to exploitation, are associated with lower macroinvertebrate assemblage taxon richness and modified habitat functioning in an Amazonian river. Between 2015 and 2017, macroinvertebrate metrics of abundance and number of families, and related habitat variables, were compared between exploited and unexploited mussel beds in the Caeté river, northeastern Pará state, Brazil. Except for Chironomidae abundance, which increased, other macroinvertebrate metrics decreased in exploited mussel beds, especially abundances of shredders and predators. Medium and high mussel densities appear to support abundant and diverse macroinvertebrate assemblages. Macroinvertebrate decreases were mainly correlated with lower organic matter in the sediment and higher dissolved solids in the water column, due to losses in mussel biodeposition and filtration functions. Amazonian freshwater mussel density is a useful indicator of abundant and diverse macroinvertebrate assemblages, and mussel beds may help prioritize locations for habitat conservation in Amazonian rivers, and indirectly for fishes that are essential for mussel dispersion. Aquatic management efforts should explicitly include mussel beds and their diverse associated macroinvertebrate assemblages.

Developing a standard approach for monitoring freshwater pearl mussel (Margaritifera margaritifera) populations in European rivers

Abstract The freshwater pearl mussel (Margaritifera margaritifera) is an endangered species in Europe, protected nationally and internationally, but with a steadily declining range and abundance owing to pressures such as pollution, river engineering, and illegal exploitation. Despite this, no consistent approaches have been developed around Europe for monitoring pearl mussel populations and their habitats. To address this need, experts on pearl mussel ecology from 11 countries met at a series of workshops in order to develop a protocol for monitoring, published under the auspices of the European Committee for Standardization (CEN). This standard is unique, as it is the first CEN standard dedicated to a single species of conservation concern. The standard is aimed at scientists, conservation bodies, and environmental regulators, and can be used for designing national monitoring programmes as well as reporting on the conservation status of pearl mussel populations under the European Habitats Directive. It contains guidance at the individual site level to determine why populations are failing to recruit, but also addresses the need for a wider‐scale approach to ensure that catchment developments do not have adverse impacts on rivers containing pearl mussels. A pearl mussel monitoring programme needs to investigate the size and viability of populations, as well as the fish hosts (Atlantic salmon, Salmo salar, or brown trout, Salmo trutta) on which pearl mussel larvae depend. Water quality, including variables such as dissolved oxygen, acid–base chemistry, and nutrient levels, is also an essential monitoring component, together with the physical features of the river bed, river flow regimes, and sediment dynamics. It is hoped that this pan‐European approach will improve the ability to compare data across many countries, and will ultimately ensure that the results of monitoring are translated into measures for improving the conservation status of the freshwater pearl mussel throughout its range.

Species traits and catchment‐scale habitat factors influence the occurrence of freshwater mussel populations and assemblages

Summary Conservation of freshwater unionid mussels presents unique challenges due to their distinctive life cycle, cryptic occurrence and imperilled status. Relevant ecological information is urgently needed to guide their management and conservation. We adopted a modelling approach, which is a novel application to freshwater mussels to enhance inference on rare species, by borrowing data among species in a hierarchical framework to conduct the most comprehensive occurrence analysis for freshwater mussels to date. We incorporated imperfect detection to more accurately examine effects of biotic and abiotic factors at multiple scales on the occurrence of 14 mussel species and the entire assemblage of the Tar River Basin of North Carolina, U.S.A. The single assemblage estimate of detection probability for all species was 0.42 (95% CI, 0.36–0.47) with no species‐ or site‐specific detection effects identified. We empirically observed 15 mussel species in the basin but estimated total species richness at 21 (95% CI, 16–24) when accounting for imperfect detection. Mean occurrence probability among species ranged from 0.04 (95% CI, 0.01–0.16) for Alasmidonta undulata, an undescribed Lampsilis sp., and Strophitus undulatus to 0.67 (95% CI, 0.42–0.86) for Elliptio icterina. Median occurrence probability among sites was &lt;0.30 for all species with the exception of E. icterina. Site occurrence probability generally related to mussel conservation status, with reduced occurrence for endangered and threatened species. Catchment‐scale abiotic variables (stream power, agricultural land use) and species traits (brood time, host specificity, tribe) influenced the occurrence of mussel assemblages more than reach‐ or microhabitat‐scale features. Our findings reflect the complexity of mussel ecology and indicate that habitat restoration alone may not be adequate for mussel conservation. Catchment‐scale management can benefit an entire assemblage, but species‐specific strategies may be necessary for successful conservation. The hierarchical multispecies modelling approach revealed findings that could not be elucidated by other means, and the approach may be applied more broadly to other river basins and regions. Accurate measures of assemblage dynamics, such as occurrence and species richness, are required to create management plans for effective conservation.

Picturing thermal niches and biomass of hydrothermal vent species

In community ecology, niche analysis is a classic tool for investigating species׳ distribution and dynamics. Components of a species׳ niche include biotic and abiotic factors. In the hydrothermal vent ecosystem, although composition and temporal variation have been investigated since these deep-sea habitats were discovered nearly 40 years ago, the roles and the factors behind the success of the dominant species of these ecosystems have yet to be fully elucidated. In the Lucky Strike vent field on the Mid-Atlantic Ridge (MAR), the dominant species is the mussel Bathymodiolus azoricus. Data on this species and its associated community were collected during four oceanographic cruises on the Eiffel Tower edifice and integrated in a novel statistical framework for niche analysis. We assessed the thermal range, density, biomass and niche similarities of B. azoricus and its associated fauna.Habitat similarities grouped mussels into three size categories: mussels with lengths ranging from 0.5 to 1.5cm, from 1.5 to 6cm, and mussels longer than 6cm. These size categories were consistent with those found in previous studies based on video imagery. The three size categories featured different associated fauna. The thermal range of mussels was shown to change with organism size, with intermediate sizes having a broader thermal niche than small or large mussels. Temperature maxima seem to drive their distribution along the mixing gradient between warm hydrothermal fluids and cold seawater. B. azoricus constitutes nearly 90% of the biomass (in g dry weight /m2) of the ecosystem. Mean individual weights were calculated for 39 of the 79 known taxa on Eiffel Tower and thermal ranges were obtained for all the inventoried species of this edifice. The analysis showed that temperature is a suitable variable to describe density variations among samples for 71 taxa. However, thermal conditions do not suffice to explain biomass variability. Our results provide valuable insights into mussel ecology, biotic interactions and the role of B. azoricus in the community.

Coupling freshwater mussel ecology and river dynamics using a simplified dynamic interaction model

AbstractFreshwater faunal diversity and abundance have declined dramatically worldwide, concurrent with changes in streamflow and sediment loads in rivers. Cumulative effects and interdependencies of chronic covarying environmental stressors can obscure causal linkages that may be controlling the population dynamics of longer-lived freshwater fauna, such as mussels. To understand changes in long-term mussel population density, we developed a dynamic, process-based interaction model that couples streamflow, suspended sediment, phytoplankton, and mussel abundance under the hypothesis that chronic exposure to increased suspended sediment and food limitation are the primary factors controlling native mussel population density in a midwestern USA agricultural river basin. We calibrated and validated the model with extensive survey data from multiple time periods and used it to evaluate changes in mussel abundance at a subbasin scale over decades. We evaluated sensitivity of simulated mussel densities across a ...

North American freshwater mussels: natural history, ecology, and conservation

This well-illustrated book highlights freshwater mussels' fabulous diversity, amazing array of often bizarre ecological adaptations and their dire conservation plight. Summarizing and synthesizing historical and contemporary information as well as original research and analysis, the book describes the diverse array of mussel life history strategies and builds a cohesive narrative culminating in the development of explicit frameworks to explain pervasive patterns in mussel ecology. The fascinating and colorful role of mussels in human society is also described in detail, including the little-known pearl button industry of the early 1900s and the wild and often violent shell harvest of the 1990s. The final chapter details humans' efforts to save these fascinating animals and gives a prognosis for the future of the North American fauna. The book provides the first comprehensive review of mussel ecology and conservation for scientists, natural resource professionals, students and natural history enthusiasts.

Population assessment and potential functional roles of native mussels in the Upper Mississippi River

Abstract Despite a heightened global concern for native mussels, fundamental research on mussel ecology in large rivers is lacking. These gaps in knowledge about where mussels occur, and why, are limiting habitat restoration activities. Large‐scale systematic surveys for native mussels in three reaches of the Upper Mississippi River documented mussel communities composed of 16–23 species and ranging from 2.9–4.5 live mussels m−2 that were actively recruiting new cohorts into their populations (87–100% of the species were found as juveniles ⩽5 years old). Estimates of mean tissue biomass and production in these reaches ranged from 2.1–3.1 g C m−2 and 0.4–0.6 g C m−2 year−1, respectively. Mussels filtered a significant amount of water (range, 0.05–0.07 m3 m−2 d−1) over a 480 km reach of the Upper Mississippi River – amounting to a filtration rate of 53.1 million m3 day−1. The filtration rate of mussels as a percentage of river discharge ranged from 0.5–1.4% at high flows (5% exceedance), from 1.5–4.4% at moderate flows (50% exceedance) and from 4.4–12.2% during low flows (95% exceedance). Collectively, these data suggest that native mussels play an integral role in this ecosystem by sequestering suspended materials that can be used by other benthic organisms. Published in 2011 by John Wiley and Sons, Ltd.

Freshwater mussel ecology: a multifactor approach to distribution and abundance

Previous articleNext article No AccessBook ReviewsFreshwater mussel ecology: a multifactor approach to distribution and abundanceCaryn C. Vaughn, Daniel C. Allen, Pascal Irmscher, and Carrie J. MillerCaryn C. VaughnOklahoma Biological Survey Ecology and Evolutionary Biology Graduate Program and Department of Zoology University of Oklahoma Norman, Oklahoma Search for more articles by this author , Daniel C. AllenOklahoma Biological Survey Ecology and Evolutionary Biology Graduate Program and Department of Zoology University of Oklahoma Norman, Oklahoma Search for more articles by this author , Pascal IrmscherOklahoma Biological Survey Ecology and Evolutionary Biology Graduate Program and Department of Zoology University of Oklahoma Norman, Oklahoma Search for more articles by this author , and Carrie J. MillerOklahoma Biological Survey Ecology and Evolutionary Biology Graduate Program and Department of Zoology University of Oklahoma Norman, Oklahoma Search for more articles by this author Oklahoma Biological Survey Ecology and Evolutionary Biology Graduate Program and Department of Zoology University of Oklahoma Norman, OklahomaPDFPDF PLUSFull Text Add to favoritesDownload CitationTrack CitationsPermissionsReprints Share onFacebookTwitterLinkedInRedditEmail SectionsMoreDetailsFiguresReferencesCited by Volume 28, Number 2June 2009 Article DOIhttps://doi.org/10.1899/28.2.BR.515.1 Views: 53Total views on this site Citations: 3Citations are reported from Crossref History Journal History This article was published in the Journal of the North American Benthological Society (1986-2011), which is continued by Freshwater Science (2012-present). © 2009 by The North American Benthological SocietyPDF download Crossref reports the following articles citing this article:Taylor E. Kelley, Garrett W. Hopper, Irene Sánchez González, Jamie R. Bucholz, Carla L. Atkinson Identifying potential drivers of distribution patterns of invasive Corbicula fluminea relative to native freshwater mussels (Unionidae) across spatial scales, Ecology and Evolution 12, no.33 (Mar 2022).https://doi.org/10.1002/ece3.8737Khaleid F. Abd El-Wakeil, Ahmed H. Obuid-Allah, Azhar H. Mohamed, Fatma El-Zahraa A. Abd El-Aziz A comparison of molluscan communities in a section of the Nile River at Assiut, Egypt, with different chemical and thermal pollution, Molluscan Research 35, no.22 (Oct 2014): 73–80.https://doi.org/10.1080/13235818.2014.919693AC. Colle, CT. Callil, , Environmental influences on the composition and structure of the freshwater mussels in shallow lakes in the Cuiabá River floodplain, Brazilian Journal of Biology 72, no.22 (May 2012): 249–256.https://doi.org/10.1590/S1519-69842012000200004

Freshwater Mussel Ecology: A Multifactor Approach to Distribution and Abundance. Freshwater Ecology Series, Volume 1. By David L. Strayer. Berkeley (California): University of California Press . $45.00. ix + 204 p.; ill.; index. 978‐0‐520‐25526‐5. 2008.

Previous articleNext article No AccessNew Biological BooksFreshwater Mussel Ecology: A Multifactor Approach to Distribution and Abundance. Freshwater Ecology Series, Volume 1. By David L. Strayer. Berkeley (California): University of California Press . $45.00. ix + 204 p.; ill.; index. 978‐0‐520‐25526‐5. 2008.Daniel W. SchneiderDaniel W. SchneiderIllinois Natural History Survey, Institute of Natural Resources Sustainability, University of Illinois, Champaign, Illinois Search for more articles by this author Illinois Natural History Survey, Institute of Natural Resources Sustainability, University of Illinois, Champaign, IllinoisPDFPDF PLUSFull Text Add to favoritesDownload CitationTrack CitationsPermissionsReprints Share onFacebookTwitterLinkedInRedditEmail SectionsMoreDetailsFiguresReferencesCited by The Quarterly Review of Biology Volume 84, Number 2June 2009 Published in association with Stony Brook University Article DOIhttps://doi.org/10.1086/603510 Views: 13Total views on this site © 2009 by The University of Chicago. All rights reserved.PDF download Crossref reports no articles citing this article.

How to Build a “Monster” from Miscellany

How to Build a “Monster” from Miscellany

Freshwater mussel ecology: a multifactor approach to distribution and abundance

Preface PART ONE: The Laboratory 1. The Model as Monster 2. The Case of Pearly Mussels PART TWO: The Monster's Parts 3. Dispersal 4. Habitat 5. Hosts 6. Food 7. Enemies 8. Implications for Conservation PART THREE: Making the Monster Walk 9. Three Models for Mussel Ecology 10. Is a Comprehensive Model Possible? Literature Cited Index

Changing Perspectives on Pearly Mussels, North America's Most Imperiled Animals

Abstract Pearly mussels (Unionacea) are widespread, abundant, and important in freshwater ecosystems around the world. Catastrophic declines in pearly mussel populations in North America and other parts of the world have led to a flurry of research on mussel biology, ecology, and conservation. Recent research on mussel feeding, life history, spatial patterning, and declines has augmented, modified, or overturned long-held ideas about the ecology of these animals. Pearly mussel research has begun to benefit from and contribute to current ideas about suspension feeding, life-history theory, metapopulations, flow refuges, spatial patterning and its effects, and management of endangered species. At the same time, significant gaps in understanding and apparent paradoxes in pearly mussel ecology have been exposed. To conserve remaining mussel populations, scientists and managers must simultaneously and aggressively pursue both rigorous research and conservation actions.

The Ecomechanics of Mussel Attachment: From Molecules to Ecosystems

One aspect of the physiological ecology of intertidal organisms is their mechanical design, which can be explored at many hierarchical levels, from molecules to ecosystems. Mechanical structures, as with any other physiological feature, require energy to construct and maintain, are subject to manufacturing and evolutionary constraints, and influence ecological performance. This contribution focuses on the ecomechanics of mussel attachment, which contributes to the competitive dominance of mussels on many wave-swept shores. Examples are presented to illustrate the hierarchical nature of mussel attachment, how levels of the hierarchy are interrelated, and where gaps in our knowledge remain. For example, water motion generates forces that mechanically deform byssal threads, but may also enhance the rate at which threads subsequently restore their original toughness. Furthermore, the ability of mussels to sense and respond to changes in their flow environment by producing a stronger attachment may be subject to physiological constraints, which in turn may have important consequences for the ecological response of mussels to shifts in wave climate. Thus an integrative approach to the study of byssal attachment is needed to fully understand this important aspect of the physiological ecology of mussels on rocky intertidal shores.

Exploitation trajectory of a declining fauna: a century of freshwater mussel fisheries in North America

Freshwater mussels (Bivalvia: Unionidae) have been an economically valuable biological resource in North America since the mid-1800s. Although the industries based upon mussel harvest are quite distinct from one another, the trends apparent in harvest statistics are remarkably similar among each successive harvest era. Whether fished for freshwater pearls, button production, or cultured pearl production, market factors have driven commercial harvests while the life history and ecology of mussels have been largely ignored. Annual yields of freshwater mussels are declining throughout the United States and catch per unit effort (CPUE) has declined dramatically in some of the most important American mussel fisheries. Harvest statistics indicate that mussel populations are dangerously depleted due to the erosion of the latest industry based upon their harvest. It seems likely that the exhaustive harvests of both the distant and recent past, coupled with habitat loss and degradation, have left North American unionid mussel populations at levels insufficient to support the substantial harvests consistently demanded by industry. This century-long exploitation trajectory provides valuable lessons about the mechanisms of fisheries collapse that are necessary to ensure the sustainable management of aquatic resources.