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Zebra Mussel Invasions (zebra + mussel_invasion)
Selected AbstractsWATER QUALITY IMPACTS AND INDICATORS OF METABOLIC ACTIVITY OF THE ZEBRA MUSSEL INVASION OF THE SENECA RIVER,JOURNAL OF THE AMERICAN WATER RESOURCES ASSOCIATION, Issue 3 2004Steven W. Effler ABSTRACT: The conspicuous shifts in summertime values of common measures of water qualify that have persisted for 10 years (1993 to 2002) in the Seneca River, New York, as a result of the zebra mussel invasion are documented. Resolution of patterns in time and space is supported by water quality monitoring that extends back to the late 1970s. Patterns are evaluated to describe the stability of impacts and quantify metabolic activity of the invader. The water quality impacts that have persisted unabated for 10 years since the invasion are the most severe documented for a river in North America. Changes in summer median conditions since the invasion include: (1) a 16-fold decrease in chlorophyll concentration (Chi), (2) a 2.5-fold increase in Secchi disc transparency, (3) a 17-fold increase in soluble reactive phosphorus concentration, (4) a 3.7-fold increase in total ammonia concentration, (5) a greater than 25 percent decrease in dissolved oxygen (DO) concentration, and (6) a decrease in pH of 0.55 units. The strength of these signatures has been driven by anthropogenic influences that include upstream nutrient loading and morphometric modifications of the river, and the functioning of Cross Lake, through which the river flows. This hypereutrophic lake sustains dense zebra mussel populations and related water quality impacts in the river downstream of the lake outflow by acting as a source of veligers and suitable food for this bivalve. Evidence is presented that levels of metabolic activity of the zebra mussel in this river have been resource limited, manifested through increased consumption of Chl and DO with increased delivery of these constituents in the lake's outflow. [source] Assessing the potential for fish predation to impact zebra mussels (Dreissena polymorpha): insight from bioenergetics modelsECOLOGY OF FRESHWATER FISH, Issue 2 2004M. A. Eggleton Abstract,,, Rates of annual food consumption and biomass were modeled for several fish species across representative rivers and lakes in eastern North America. Results were combined to assess the relative potential of fish predation to impact zebra mussels (Dreissena polymorpha). Predicted annual food consumption by fishes in southern waters was over 100% greater than that in northern systems because of warmer annual water temperatures and presumed increases in metabolic demand. Although generally increasing with latitude, biomasses of several key zebra mussel fish predators did not change significantly across latitudes. Biomasses of some less abundant fish predators did increase significantly with latitude, but increases were not of the magnitude to offset predicted decreases in food consumption. Our results generally support the premise that fishes in rivers and lakes of the southern United States (U.S.) have inherently greater potential to impact zebra mussels by predation. Our simulations may provide a partial explanation of why zebra mussel invasions have not been as rapid and widespread in southern U.S. waters compared to the Great Lakes region. Resumen 1Modelamos la tasa de consumo anual de alimento y biomasa para varias especies de peces en una muestra representativa de ríos y lagos del este de Norte América. Combinamos los resultados para evaluar el potencial relativo que estas especies de peces pueden ejercer sobre la abundancia del mejillón asiático Dreissena polymorpha. Las predicciones sobre consumo para peces en lagos y ríos del sur fueron más del 100% comparadas con sistemas septentrionales. Esto se puede deber a las temperaturas anuales más altas y aumentos en la demanda metabólica de peces en ríos y lagos del sur de Norte América. 2La biomasa de varias especies claves de peces que consumen D. polymorpha no cambió apreciablemente con latitud. La biomasa de algunos peces que consumen D. polymorpha aumentó significativamente con latitud, pero este aumento no era de una magnitud suficiente para compensar la disminución en el consumo de alimento. 3Nuestros resultados apoyan generalmente la premisa de que los peces en ríos y lagos del sur de los Estados Unidos (EE.UU.) tienen un potencial inherente mayor para poder controlar D. polymorpha. Nuestras simulaciones proporcionan una explicación parcial de por qué las invasiones de D. polymorpha no han sido tan rápidas y ampliamente distribuidas en aguas sureñas comparado con la región de los Grandes Lagos. [source] Predicting the impacts of an introduced species from its invasion history: an empirical approach applied to zebra mussel invasionsFRESHWATER BIOLOGY, Issue 6 2003Anthony Ricciardi SUMMARY 1.,Quantitative models of impact are lacking for the vast majority of known invasive species, particularly in aquatic ecosystems. Consequently, managers lack predictive tools to help them prioritise invasion threats and decide where they can most effectively allocate limited resources. Predictive tools would also enhance the accuracy of water quality assessments, so that impacts caused by an invader are not erroneously attributed to other anthropogenic stressors. 2.,The invasion history of a species is a valuable guide for predicting the consequences of its introduction into a new environment. Regression analysis of data from multiple invaded sites can generate empirical models of impact, as is shown here for the zebra mussel Dreissena polymorpha. Dreissena's impacts on benthic invertebrate abundance and diversity follow predictable patterns that are robust across a range of habitat types and geographic regions. Similar empirical models could be developed for other invaders with a documented invasion history. 3.,Because an invader's impact is correlated with its abundance, a surrogate model may be generated (when impact data are unavailable) by relating the invader's abundance to environmental variables. Such a model could help anticipate which habitats will be most affected by invasion. Lack of precision should not be a deterrent to developing predictive models where none exist. Crude predictions can be refined as additional data become available. Empirical modelling is a highly informative and inexpensive, but underused, approach in the management of aquatic invasive species. [source] Molecular ecology of zebra mussel invasionsMOLECULAR ECOLOGY, Issue 4 2006GEMMA E. MAY Abstract The invasion of the zebra mussel, Dreissena polymorpha, into North American waters has resulted in profound ecological disturbances and large monetary losses. This study examined the invasion history and patterns of genetic diversity among endemic and invading populations of zebra mussels using DNA sequences from the mitochondrial cytochrome oxidase I (COI) gene. Patterns of haplotype frequency indicate that all invasive populations of zebra mussels from North America and Europe originated from the Ponto-Caspian Sea region. The distribution of haplotypes was consistent with invasive populations arising from the Black Sea drainage, but could not exclude the possibility of an origin from the Caspian Sea drainage. Similar haplotype frequencies among North American populations of D. polymorpha suggest colonization by a single founding population. There was no evidence of invasive populations arising from tectonic lakes in Turkey, while lakes in Greece and Macedonia contained only Dreissena stankovici. Populations in Turkey might be members of a sibling species complex of D. polymorpha. Ponto-Caspian derived populations of D. polymorpha (, = 0.0011) and Dreissena bugensis (one haplotype) exhibited low levels of genetic diversity at the COI gene, perhaps as a result of repeated population bottlenecks. In contrast, geographically isolated tectonic lake populations exhibited relatively high levels of genetic diversity (, = 0.0032 to 0.0134). It is possible that the fluctuating environment of the Ponto-Caspian basin facilitated the colonizing habit of invasive populations of D. polymorpha and D. bugensis. Our findings were concordant with the general trend of destructive freshwater invaders in the Great Lakes arising from the Ponto-Caspian Sea basin. [source] | ||||||||||