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34 records · Page 2Linked to original sources
USGS1998

Evaluation of several chemical disinfectants for removing zebra mussels from unionid mussels

We evaluated the safety and effectiveness of chemical treatments for killing veliger and juvenile stages of the zebra mussel Dreissena polymorpha attached to unionid mussels. Static toxicity tests were conducted on eight unionid mussel species with common aquaculture chemicals (benzalkonium chloride, formalin, hydrogen peroxide, calcium chloride, potassium chloride, and sodium chloride). The concentration and duration of each chemical treatment tested had previously been found to kill zebra mussel veligers and juveniles. Several species (e.g., Elliptio dilatata, Lampsilis cardium and Lasmigona complanata ) incurred less than 10% mortality in chloride salt treatments, while in other species (e.g., Obliquaria reflexa and Leptodea fragilis ) mortality varied greatly among treatment regimes. Treatments with benzalkonium chloride, formalin, and hydrogen peroxide were less than 90% effective on juvenile stages of zebra mussels and, therefore, were ruled out after preliminary trials. Limited application of specific chemical treatments may be feasible for more tolerant species; however, effective disinfection of unionid shells will require the use of chemical treatment followed by a quarantine period to completely remove zebra mussel larvae and juveniles.

Progressive Fish-Culturist↗
USGS2019

Long-term population dynamics of dreissenid mussels (Dreissena polymorpha and D. rostriformis): A cross-system analysis

Dreissenid mussels (including the zebra mussel Dreissena polymorpha and the quagga mussel D. rostriformis ) are among the world's most notorious invasive species, with large and widespread ecological and economic effects. However, their long‐term population dynamics are poorly known, even though these dynamics are critical to determining impacts and effective management. We gathered and analyzed 67 long‐term (>10 yr) data sets on dreissenid populations from lakes and rivers across Europe and North America. We addressed five questions: (1) How do Dreissena populations change through time? (2) Specifically, do Dreissena populations decline substantially after an initial outbreak phase? (3) Do different measures of population performance (biomass or density of settled animals, veliger density, recruitment of young) follow the same patterns through time? (4) How do the numbers or biomass of zebra mussels or of both species combined change after the quagga mussel arrives? (5) How does body size change over time? We also considered whether current data on long‐term dynamics of Dreissena populations are adequate for science and management. Individual Dreissena populations showed a wide range of temporal dynamics, but we could detect only two general patterns that applied across many populations: (1) Populations of both species increased rapidly in the first 1–2 yr after appearance, and (2) quagga mussels appeared later than zebra mussels and usually quickly caused large declines in zebra mussel populations. We found little evidence that combined Dreissena populations declined over the long term. Different measures of population performance were not congruent; the temporal dynamics of one life stage or population attribute cannot generally be accurately inferred from the dynamics of another. We found no consistent patterns in the long‐term dynamics of body size. The long‐term dynamics of Dreissena populations probably are driven by the ecological characteristics (e.g., predation, nutrient inputs, water temperature) and their temporal changes at individual sites rather than following a generalized time course that applies across many sites. Existing long‐term data sets on dreissenid populations, although clearly valuable, are inadequate to meet research and management needs. Data sets could be improved by standardizing sampling designs and methods, routinely collecting more variables, and increasing support.

Ecosphere↗
USGS2009

Characteristics of a refuge for native freshwater mussels (Bivalvia: Unionidae) in Lake St. Clair

The Lake St. Clair delta (??? 100??km 2 ) provides an important refuge for native freshwater mussels (Unionidae) wherein 22 of the ??? 35 historical species co-occur with invasive dreissenids. A total of 1875 live unionids representing 22 species were found during snorkeling surveys of 32 shallow (??? 1??m) sites throughout the delta. Richness and density of unionids and zebra mussel infestation rates varied among sites from 3 to 13 unionid species, 0.02 to 0.12 unionids/m 2 , and < 1 to 35 zebra mussels/unionid, respectively. Zebra mussel infestation of unionids in the delta appears to be mitigated by dominant offshore currents, which limit densities of zebra mussel veligers in nearshore compared to offshore waters (13,600 vs. 28,000/m 3 , respectively). Glycogen concentrations in the tissues of a common and widespread species in the delta (Lampsilis siliquoidea) suggest that zebra mussels may be adversely affecting physiological condition of unionids in a portion of the Lake St. Clair delta. Physiological condition and community structure of unionids within the delta may also be influenced by differences in food quantity and quality resulting from the uneven distribution of water flowing from the St. Clair River. The delta likely supports the largest living unionid community in the lower Great Lakes and includes several species that have been listed as Endangered or Threatened in Canada and/or the state of Michigan, making it an important refuge for the conservation of native unionids. Crown Copyright ?? 2009.

Journal of Great Lakes Research↗
USGS2011

Physiological effects of potassium chloride, formalin and handling stress on bonytail

We characterized the sublethal physiological changes in bonytail Gila elegans subjected to consecutive 750-mg/L potassium chloride (KCl) and 25-mg/L formalin treatments for the removal of zebra mussel Dreissena polymorpha and quagga mussel D. bugensis veligers. Plasma cortisol, glucose, and osmolality were measured over 24 h and at 14 d posthandling after exposing bonytail to KCl and one net stressor (capture with a net), KCl plus formalin and two net stressors, and one or two net stressors without chemicals. Elevated plasma cortisol (322–440 ng/mL) and glucose (254–399 mg/dL) concentrations were observed in all treatments compared with the concentrations in control fish (plasma cortisol, 56 ng/mL; glucose, 43 mg/dL). While there were no detectable differences in plasma osmolality among the treatment and control fish, a difference was observed between fish that were handled once versus twice. Chemical effects of stress were not observed in any of the physiological responses when the KCl treatment was compared with the one-net stressor treatment or when the KCl plus formalin treatment was compared with the two-net stressor treatment. Cumulative responses, however, were observed between one net stressor and two net stressors for plasma glucose and osmolality but not for plasma cortisol. Plasma cortisol and glucose levels remained elevated at 24 h posthandling, indicating that bonytail had not completely recovered from the handling stressors and would benefit from a recovery period in protected refugia before being released.

North American Journal of Fisheries Management↗
USGS2025

Carbon dioxide infusion reduces invasive mussel biofouling (quagga mussel; Dreissena rostriformis bugensis) in raw water systems

The efficacy of carbon dioxide (CO 2 ) to reduce biofouling by quagga mussels ( Dreissena rostriformis bugensis ) in raw water systems was investigated. Experiments were conducted in a mobile laboratory located at Bureau of Reclamation Davis Dam Hydropower Facility and supplied with raw water from Lake Mohave, a reservoir of the Colorado River, USA. Incoming water was split between five chambers, each infused with CO 2 at a different rate. Raw reservoir water containing quagga larvae (veligers) was mixed with CO 2 chamber outflows and delivered to tanks containing settlement plates. Two experiments were conducted. Experiment 1 tested continuous infusion at target concentrations of 30, 45, 60, 75, and 100 mg L -1 dCO 2 (dissolved CO 2 ). Experiment 2 evaluated intermittent infusion schedules: 24 h on/off with 50, 75, and 100 mg L -1 dCO 2 and 24 h once/week with 100 mg L -1 dCO 2 . In Experiment 1, the percent settlement decreased with mean CO 2 concentration, ranging from 5.0% to < 0.1% in 28.7 and 92.2 mg L -1 dCO 2 , respectively. In Experiment 2, the efficacy of 24 h on/off at dCO 2 > 72.2 mg L -1 was similar to continuous treatment. The least effective treatment was 24 h once weekly at 95 mg L -1 dCO 2 . These results demonstrate that CO 2 treatment may reduce mussel biofouling in raw water systems.

Arizona, Nevada↗
USGS1996

Comparative biology of zebra mussels in Europe and North America: an overview

SYNOPSIS. Since the discovery of the zebra mussel, Dreissena polymorpha , in the Great Lakes in 1988 comparisons have been made with mussel populations in Europe and the former Soviet Union. These comparisons include: Population dynamics, growth and mortality rates, ecological tolerances and requirements, dispersal rates and patterns, and ecological impacts. North American studies, mostly on the zebra mussel and a few on a second introduced species, the quagga mussel, Dreissena bugensis , have revealed some similarities and some differences. To date it appears that North American populations of zebra mussels are similar to European populations in their basic biological characteristics, population growth and mortality rates, and dispersal mechanisms and rates. Relative to European populations differences have been demonstrated for: (1) individual growth rates; (2) life spans; (3) calcium and pH tolerances and requirements; (4) potential distribution limits; and (5) population densities of veligers and adults. In addition, studies on the occurrence of the two dreissenid species in the Great Lakes are showing differences in their modes of life, depth distributions, and growth rates. As both species spread throughout North America, comparisons between species and waterbodies will enhance our ability to more effectively control these troublesome species.

American Zoologist↗
USGS2014

Diet of Mysis diluviana reveals seasonal patterns of omnivory and consumption of invasive species in offshore Lake Michigan

Recent changes in Lake Michigan&rsquo;s lower trophic levels were hypothesized to have influenced the diet of omnivorous Mysis diluviana. In this study, the stomach contents of Mysis were examined from juvenile and adults collected monthly (April&ndash;October) from a 110-m bottom depth site to describe their seasonal diet in LakeMichigan during 2010. Diatoms were the most common prey item ingested, followed by calanoid copepods, and chrysophytes. Dreissenid veligers were documented in mysid diets for the first time in the Great Lakes, and Cercopagis pengoi were not only consumed but even preferred by adults in summer. Diet proportions by weight were dominated by calanoids, although diets showed a marked shift toward cladocerans in autumn. Juvenile and adult Mysis selected primarily for cladoceran prey but also selected for some calanoid copepod taxa. Comparing available Mysis diet data from 1985 to 2010 indicated generally fewer cladocerans and rotifers per gut and less consistent differences in copepods and Peridinium consumed. The seasonal composition of phyto- and zooplankton prey documented herein should be useful to those seeking to understand the trophic role of Mysis in offshore food webs, but caution should be expressed when generalizing similarities in Mysis diets across other lakes because Lake Michigan&rsquo;s population seems relatively more herbivorous.

Lake Michigan↗
USGS1994

Identification of larvae: The zebra mussel ( Dreissena polymorpha ), quagga mussel ( Dreissena rosteriformis bugensis ), and Asian clam ( Corbicula fluminea )

There are presently four freshwater bivalves in the United States that produce larvae or veligers commonly found in the water column: two forms of Asian clams and two species of dreissenids. Portions of the geographic range of three of these bivalves, one species of Asian clam ( Corbicula fluminea ), zebra mussels ( Dreissena polymorpha ), and quagga mussels ( Dreissena rosteriformis bugensis ), overlap, causing problems with larval identification. To determine which characteristics can be used to separate larval forms, adult Asian clams, quaggas, and zebra mussels were brought into the laboratory and induced to spawn, and the resulting larvae were reared. Hybrids between quaggas and zebra mussels were also produced, but not reared to maturity. Characteristics allowing for the most rapid and accurate separation of larvae were hinge length, shell length/height, shell shape, shell size, and the presence or absence of a foot and velum. These characteristics were observed in laboratory-reared larvae of known parentage and field-caught larvae of unknown parentage. In most cases, larvae of the Asian clam can be readily separated from those produced by either type of dreissenid on the basis of shell size and presence of a foot. Separating the gametes and embryos of the two types of dreissenids is not possible, but after shell formation, most of the larval stages can be distinguished. Hinge length, shell length/height, and the similarity in size of the shell valves can be used to separate straight-hinged, umbonal, pediveliger, and plantigrade larvae. Quagga &times; zebra mussel hybrids show characteristics of both parents and are difficult to identify.

Canadian Journal of Zoology↗
USGS1998

Impact of zebra and quagga mussels (Dreissena spp.) on freshwater unionids (Bivalvia: Unionidae) in the Detroit River of the Great Lakes

To assess the impact of zebra and quagga mussel ( Dreissena spp.) infestation on unionids, unionids (Bivalvia: Unionidae) were sampled in the Detroit River in 1982–1983, before mussels invaded the river, and in 1992 and 1994, after mussels invaded the river. Live unionids at four stations along the southeastern shore accounted for 97% (20 species) of all shells collected in 1982–1983, whereas live unionids accounted for only 10% (13 species) in 1992. A similar decline in live unionids occurred at nine stations along the northwestern shore, except the decline occurred over the three sampling periods: in 1982–83, 84% (22 species) were live; in 1992, 65% (26 species) were live; and, in 1994, only 3% (13 species) were live. The difference in time to near-total mortality of unionids along the southeastern and northwestern shores is attributed to differences in the time of invasion and abundance of zebra mussel veligers in distinct water masses emanating from Lake St. Clair located immediately upstream of the Detroit River. Although individuals of all species of all unionid subfamilies declined between 1982 and 1992/1994, members of the subfamilies Anodontinae and Lampsilinae declined more than Ambleminae. Between 1986 and 1992/1994, five Anodontinae, three Lampsilinae and 0 Ambleminae species have been extirpated from the river due to dreissenid mussel infestation. Numbers of individuals of commonly found species declined more than numbers of individuals of uncommonly found species. However, the number of uncommon species declined 47% (17 to 9) along both the southeastern and northwestern shores, whereas common species remained the same (3 species) along the southeastern shore and declined only 40% (5 to 3 species) along the northwestern shore. This study, and others, suggest that high mortality of unionids can occur between 4 and 6 yr after initial invasion by dreissenids or up to 8 yr depending on water current patterns. Infestation-induced mortality of unionids in the Detroit River is similar to that observed at a few locations in other rivers, but is higher over a larger area than that measured in other rivers to date, probably because the Detroit River was the first to be colonized by dreissenid mussels in North America.

Michigan, Ontario↗
USGS2016

Spatial variation in biofouling of a unionid mussel ( Lampsilis siliquoidea ) across the western basin of Lake Erie

Invasion of North American waters by nonnative Dreissena polymorpha and D. rostriformis bugensis has resulted in declines of the Unionidae family of native North American mussels. Dreissenid mussels biofoul unionid mussels in large numbers and interfere with unionid movement, their acquisition of food, and the native mussels' ability to open and close their shells. Initial expectations for the Great Lakes included extirpation of unionids where they co-occurred with dreissenids, but recently adult and juvenile unionids have been found alive in several apparent refugia. These unionid populations may persist due to reduced dreissenid biofouling in these areas, and/or due to processes that remove biofoulers. For example locations inaccessible to dreissenid veligers may reduce biofouling and habitats with soft substrates may allow unionids to burrow and thus remove dreissenids. We deployed caged unionid mussels ( Lampsilis siliquoidea ) at 36 sites across the western basin of Lake Erie to assess spatial variation in biofouling and to identify other areas that might promote the persistence or recovery of native unionid mussels. Biofouling ranged from 0.03 &ndash; 26.33 g per mussel, reached a maximum in the immediate vicinity of the mouth of the Maumee River, and appeared to primarily consist of dreissenid mussels. A known mussel refugium in the vicinity of a power plant near the mouth of the Maumee actually exhibited very high biofouling rates, suggesting that low dreissenid colonization did not adequately explain unionid survival in this refugium. In contrast, the southern nearshore area of Lake Erie, near another refugium, had very low biofouling. A large stretch of the western basin appeared to have low biofouling rates and muddy substrates, raising the possibility that these open water areas could support remnant and returning populations of unionid mussels. Previous observations of unionid refugia and the occurrence of low biofouling rates in large areas of the western basin of Lake Erie raise the possibility that unionid and dreissenid coexistence may be possible here and elsewhere.

Michigan, Ohio↗
USGS2019

Environmental DNA as a tool to help inform zebra mussel, Dreissena polymorpha, management in inland lakes

Zebra mussels ( Dreissena polymorpha ) are an aquatic invasive species that plague much of North America and are difficult to impossible to eradicate once they become established. Therefore, prevention and monitoring are key elements in the control of these organisms. Traditional microscopy is commonly used in monitoring but requires the presence of larval veligers. This limits the times when resource managers can monitor for the presence in northern lakes. A new monitoring tool, environmental DNA (eDNA), may allow for a more efficient and cost-effective monitoring program for zebra mussels. We developed and tested an environmental DNA assay in the fall and spring for zebra mussels in two Minnesota lakes, one heavily infested and another newly infested. We found that DNA copy numbers tended to be higher near the lake bottom and DNA was more concentrated in softer substrates. We also found that the amount of zebra mussel DNA sampling in winter resulted in similar results to when sampled in fall. This suggests that one could collect and analyze eDNA for zebra mussels during winter months to help inform future efforts in monitoring and control.

Minnesota↗
USGS2021

Use of carbon dioxide to prevent zebra mussel (Dreissena polymorpha) settlement and effects on native mussels (Order Unionoida) and benthic communities

We determined the efficacy of carbon dioxide (CO2) for preventing larval (veliger) settlement of the invasive zebra mussel (Dreissena polymorpha) and compared the response of native juvenile mussels and macroinvertebrate and periphyton communities to hypercapnia. A microcosm system of control (ambient Camb) and CO2 treatments [low PCO2 (Clow)=35,094 &micro;atm, and high PCO2 (Chigh)=66,685 &micro;atm)] was supplied with river water for 11 weeks. We measured zebra mussel settlement, juvenile native mussel (Lampsilis cardium and L. siliquoidea) growth and condition, and macroinvertebrate and periphyton community composition. Zebra mussels settled in all Camb tanks (n=4) from early July through August compared to one mussel in a CO2 treatment tank over the same period. Native mussel growth, tissue condition, and shell condition were reduced in CO2, particularly in the highest treatment. Benthic biomass (excluding zebra mussels) was similar in Camb and Clow but was reduced in Chigh. Macroinvertebrate community composition differed among treatments due to greater abundance of Chironomidae in Clow and Oligochaeata in Chigh. Periphyton abundance and richness increased in both CO2 treatments and was driven by increases in Cyanobacteria, Bacillariophyta and Chlorophyta. Our results indicate that efficacious levels of CO2 (~35,000 &micro;atm PCO2) for reducing biofouling by dreissenids are tolerable to most freshwater benthic taxa. Chronic elevated CO2 infusion (&gt;35,000 &micro;atm PCO2) may reduce native mussel growth and condition and alter benthic invertebrate and periphyton community composition. Further refinement of CO2 application strategies is needed to determine minimal effective dose and duration to prevent dreissenid settlement and minimize effects on nontarget organisms.

Management of Biological Invasions↗
USGS1989

The zebra mussel, Dreissena polymorpha (Pallas, 1771), in North America: impact on raw water users

The zebra mussel, Dreissena polymorpha (Pallas), is a small mollusc native to the Black, Caspian, and Azov Seas that was discovered in Lake Erie of the Laurentian Great Lakes of North America in 1988. Its presence there raises immediate concerns for users of raw water because it can become abundant enough to obstruct the flow of water through pipes, hoses, screens, and condensers. Biofouling attributed to this mussel was observed at several power plants, water treatment plants, and food processing and industrial facilities along Lake Erie in 1989. Estimated densities at one power plant intake canal were as high as 700,000 per m2. In addition, large numbers were found in main steam condensors and in the service water system, threatening the water supply for cooling, fire protection, and dust suppression systems. Municipal water intakes along the Canadian and United States shorelines have also been impaired. In one southeast Michigan city, drinking water withdrawal from Lake Erie was reduced 45% by the mussel. Routine checks of raw water supplies for free-floating zebra mussel veligers are reommended to determine if reproducing adult populations are present in local water bodies. After an early alert, raw water intakes could be protected to alleviate damage from the biofouling zebra mussel.

Lake Erie↗
USGS1990

Remarkable invasion of San Francisco Bay (California, USA), by the Asian clam Potamocorbula amurensis. I. Introduction and dispersal

The euryhaline bivalve mollusc Potamocorbula amurensis (family Corbulidae), a native of China, Japan, and Korea, has recently appeared and become very abundant in San Francisco Bay. This clam appears to have been introduced as veliger larvae in the seawater ballast of cargo vessels. It was first collected in northern San Francisco Bay in late 1986. P, amurensis then spread throughout the estuary within 2 yr and reached densities at some sites exceeding 10 000 m -2 It lives primarily in the subtidal on all substrates (mud, sand, peat, and clay) and is found in the full range of bay salinities (< 1 to 33%). Its explosive increase in abundance and spread may result in major alterations of the San Francisco Bay estuary ecosystem. These could include changes in (1) trophic dynamics (through competition with other suspension-feeding and deposit-feeding infauna; changes in benthic community energy flow; availability of a new and abundant prey item for birds, fish, and crabs; and reduction - as a result of its filter feeding - of phytoplankton standmg stock) and (2) benthic dynamics (through inhibition and/or enhancement of infauna due to substrate destabilization; alteration of suspended sediment load of near-bottom water; and change of sediment surface redox balance). The early detection of the appearance and spread of P. amurensis in San Francisco Bay makes this one of the best documented invasions of any estuary in the world.

California↗
USGS1994

Molluscan evidence for a late Pleistocene sea-level lowstand from Monterey Bay, central California

One hundred and twenty-three molluscan taxa are reported from four samples collected from a sea level lowstand deposit located between 100 m and 300 m below sea level in Monterey Bay, central California. Ecological interpretations of these mollusks suggest temperatures essentially equivalent to those from Puget Sound, Washington, to southern British Columbia; much cooler water than exists in Monterey Bay today; and water depths of about 10 to 50 m. Chlamys rubida from these deposits yield a 14C age determination of about 17,000 yr B. P. This age is generally equivalent to a worldwide sea level lowstand between 20,000 and 15,000 yr B. P. of at least 100 m below modern sea level. The cooler and shallow-water aspect of the lowstand molluscan fauna is in full accord with the late Pleistocene paleogeography of Monterey Bay.

California↗