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Full-Text Articles in Physical Sciences and Mathematics

Assessment Of Hazard Metrics For Predicting Field Benthic Invertebrate Toxicity In The Detroit River, Ontario, Canada, Kerry N. Mcphedren, Alice Grigicak-Mannnion, Gord Paterson, Briggs Tedd, Jan J.H. Ciborowski, G. Douglass Haffner, Ken G. Drouillard Mar 2016

Assessment Of Hazard Metrics For Predicting Field Benthic Invertebrate Toxicity In The Detroit River, Ontario, Canada, Kerry N. Mcphedren, Alice Grigicak-Mannnion, Gord Paterson, Briggs Tedd, Jan J.H. Ciborowski, G. Douglass Haffner, Ken G. Drouillard

Great Lakes Institute for Environmental Research Publications

Numerical sediment quality guidelines (SQGs) are frequently used to interpret site specific sediment chemistry and predict potential toxicity to benthic communities. These SQGs are useful for a screening line of evidence (LOE) that can be combined with other LOEs in a full weight of evidence (WOE) assessment of impacted sites. Three common multi-chemical hazard quotient methods (PEC-Qavg, PEC-Qmet and PEC-Qsum) and a novel (Hazard Score; HZD) approach were used in conjunction with a consensus based set of SQGs to evaluate the ability of different scoring metrics to predict the biological effects of sediment contamination under …


Is It Appropriate To Composite Fish Samples For Mercury Trend Monitoring And Consumption Advisories?, Ken G. Drouillard, Nilima Gandhi, Satyendra P. Bhavsar, Sarah B. Gewurtz, George B. Arhonditsis, Steve Petro Jan 2016

Is It Appropriate To Composite Fish Samples For Mercury Trend Monitoring And Consumption Advisories?, Ken G. Drouillard, Nilima Gandhi, Satyendra P. Bhavsar, Sarah B. Gewurtz, George B. Arhonditsis, Steve Petro

Great Lakes Institute for Environmental Research Publications

Monitoring mercury levels in fish can be costly because variation by space, time, and fish type/size needs to be captured. Here, we explored if compositing fish samples to decrease analytical costs would reduce the effectiveness of the monitoring objectives. Six compositing methods were evaluated by applying them to an existing extensive dataset and examining their performance in reproducing the fish consumption advisories and temporal trends. The methods resulted in varying amount (average 34-72%) of reductions in samples, but all (except one) reproduced advisories very well (96-97% of the advisories did not change or were one category more restrictive compared to …


Fullfact: An R Package For The Analysis Of Genetic And Maternal Variance Components From Full Factorial Mating Designs, Aimee Lee S. Houde, Trevor E. Pitcher Jan 2016

Fullfact: An R Package For The Analysis Of Genetic And Maternal Variance Components From Full Factorial Mating Designs, Aimee Lee S. Houde, Trevor E. Pitcher

Great Lakes Institute for Environmental Research Publications

Full factorial breeding designs are useful for quantifying the amount of additive genetic, nonadditive genetic, and maternal variance that explain phenotypic traits. Such variance estimates are important for examining evolutionary potential. Traditionally, full factorial mating designs have been analyzed using a two-way analysis of variance, which may produce negative variance values and is not suited for unbalanced designs. Mixed-effects models do not produce negative variance values and are suited for unbalanced designs. However, extracting the variance components, calculating significance values, and estimating confidence intervals and/or power values for the components are not straightforward using traditional analytic methods. We introduce fullfact …


Quantitative Biomonitoring In The Detroit River Using Elliptio Complanata: Verification Of Steady State Correction Factors And Temporal Trends Of Pcbs In Water Between 1998-2015, Ken G. Drouillard, Mark Cook, Todd A. Leadley, Paul Drca, Ted Briggs, G Douglas Haffner Jan 2016

Quantitative Biomonitoring In The Detroit River Using Elliptio Complanata: Verification Of Steady State Correction Factors And Temporal Trends Of Pcbs In Water Between 1998-2015, Ken G. Drouillard, Mark Cook, Todd A. Leadley, Paul Drca, Ted Briggs, G Douglas Haffner

Great Lakes Institute for Environmental Research Publications

Quantitative biomonitoring methods were applied to determine PCB concentrations in water from the Detroit River over a 17 year period. During 2014, mussels were deployed for and extended duration (21-364 d) and time dependent PCB concentrations were fit to a bioaccumulation model to estimate elimination coefficients (ktot) and provide site specific calibration of mussel toxicokinetics. The site specific calibration and different ktot versus KOW relationships from the literature were used to correct for steady state. ∑PCB concentrations in water were not significantly dependent on the ktot values used indicating that individual variation exceeds error contributed …


Determination Of Pcb Elimination Coefficients In Round Goby And Tubenose Goby, Xin Sun, Tim B. Johnson, Ken G. Drouillard Jan 2016

Determination Of Pcb Elimination Coefficients In Round Goby And Tubenose Goby, Xin Sun, Tim B. Johnson, Ken G. Drouillard

Great Lakes Institute for Environmental Research Publications

Whole-body elimination coefficients of polychlorinated biphenyls (PCBs) were determined in two Great Lakes invasive fish species, round goby (Neogobius melanostomus) and tubenose goby (Proterorhinus semilunaris). Elimination rates were determined for a set of model PCB congeners (n=12 congeners) dosed to fish by intraperitoneal injection and allowed to depurate at a temperature of 21.4oC for 90 d. Eight PCBs (PCB 6, 13, 21, 57, 62, 68, 89, 112 and 125) exhibited significant elimination by round goby and had corresponding half lives ranging from 13 to 39.8 d. For tubenose goby, four congeners (PCBs 21, 58, …


Uncovering Adaptive Versus Acclimatized Alterations In Standard Metabolic Rate In Brown Bullhead (Ameiurus Nebulosus), Tood A. Leadley, Anne Mcleod, Timothy B. Johnson, Daniel D. Heath, Ken G. Drouillard Nov 2015

Uncovering Adaptive Versus Acclimatized Alterations In Standard Metabolic Rate In Brown Bullhead (Ameiurus Nebulosus), Tood A. Leadley, Anne Mcleod, Timothy B. Johnson, Daniel D. Heath, Ken G. Drouillard

Great Lakes Institute for Environmental Research Publications

Standard metabolic rates (SMR) were measured in Brown Bullheads collected from two locations of the Detroit River, North America, representative of highly contaminated and uncontaminated areas. Measurements of SMR were completed within 10 d of fish collections (acute trials), for fish held in a common pond environment for 1 year (clearance trials) and for F1 generation fish raised in the pond environment (F1 study). SMRs were significantly higher (26%) in fish from the contaminated area during acute trials. Both populations showed large decreases in SMR (49 to 52 %) following clearance, however, differences between populations were still evident. There were …


A Comparison Of The Bioaccumulation Potential Of Mercury And Polychlorinated Biphenyls In Goldfish (Carassius Auratus), Jiajia Li, Ken G. Drouillard, Brian Braunfireun, Douglass G. Haffner Sep 2015

A Comparison Of The Bioaccumulation Potential Of Mercury And Polychlorinated Biphenyls In Goldfish (Carassius Auratus), Jiajia Li, Ken G. Drouillard, Brian Braunfireun, Douglass G. Haffner

Great Lakes Institute for Environmental Research Publications

Both mercury (Hg) and polychlorinated biphenyls (PCBs) demonstrate food web biomagnification in aquatic ecosystems, yet their toxicokinetics have not been simultaneously contrasted within a common fish species. This study quantifies uptake and elimination rates of Hg and PCBs in goldfish. Fish were exposed to contaminated food containing PCBs and Hg to determine dietary chemical assimilation efficiencies (AEs) and elimination coefficients (ktot). To test first-order kinetics, three exposure regimes were established by varying the proportion of contaminated fish incorporated into the food. Dietary AEs were 98 ± 10, 75 ± 12, and 40 ± 9% for MeHg, THg, and …


Pcb Food Web Dynamics Quantify Nutrient And Energy Flow In Aquatic Ecosystems, Anne M. Mcleod, Gord Paterson, Ken G. Drouillard, Douglas G. Haffner Jan 2015

Pcb Food Web Dynamics Quantify Nutrient And Energy Flow In Aquatic Ecosystems, Anne M. Mcleod, Gord Paterson, Ken G. Drouillard, Douglas G. Haffner

Great Lakes Institute for Environmental Research Publications

Measuring in situ nutrient and energy flows in spatially and temporally complex aquatic ecosystems represents a major ecological challenge. Food web structure, energy and nutrient budgets are difficult to measure, and it is becoming more important to quantify both energy and nutrient flow to determine how food web processes and structure are being modified by multiple stressors. We propose that polychlorinated biphenyl (PCB) congeners represent an ideal tracer to quantify in situ energy and nutrient flow between trophic levels. Here, we demonstrate how an understanding of PCB congener bioaccumulation dynamics provides multiple direct measurements of energy and nutrient flow in …


Hierarchical Analysis Of Genetic Structure In The Habitat-Specialist Eastern Sand Darter (Ammocrypta Pellucida), Robert Ginson, Ryan P. Walter, Nicholas E. Mandrak, Courtney L. Beneteau, Daniel D. Heath Jan 2015

Hierarchical Analysis Of Genetic Structure In The Habitat-Specialist Eastern Sand Darter (Ammocrypta Pellucida), Robert Ginson, Ryan P. Walter, Nicholas E. Mandrak, Courtney L. Beneteau, Daniel D. Heath

Great Lakes Institute for Environmental Research Publications

Quantifying spatial genetic structure can reveal the relative influences of contemporary and historic factors underlying localized and regional patterns of genetic diversity and gene flow - important considerations for the development of effective conservation efforts. Using 10 polymorphic microsatellite loci, we characterize genetic variation among populations across the range of the Eastern Sand Darter (Ammocrypta pellucida), a small riverine percid that is highly dependent on sandy substrate microhabitats. We tested for fine scale, regional, and historic patterns of genetic structure. As expected, significant differentiation was detected among rivers within drainages and among drainages. At finer scales, an unexpected lack of …


Benefits Of Turbid River Plume Habitat For Lake Erie Yellow Perch (Perca Flavescens) Recruitment Determined By Juvenile To Larval Genotype Assignment, Lucia B. Carreon-Martinez, Ryan P. Walter, Timothy B. Johnson, Stuart A. Ludsin, Daniel D. Heath Jan 2015

Benefits Of Turbid River Plume Habitat For Lake Erie Yellow Perch (Perca Flavescens) Recruitment Determined By Juvenile To Larval Genotype Assignment, Lucia B. Carreon-Martinez, Ryan P. Walter, Timothy B. Johnson, Stuart A. Ludsin, Daniel D. Heath

Great Lakes Institute for Environmental Research Publications

Nutrient-rich, turbid river plumes that are common to large lakes and coastal marine ecosystems have been hypothesized to benefit survival of fish during early life stages by increasing food availability and (or) reducing vulnerability to visual predators. However, evidence that river plumes truly benefit the recruitment process remains meager for both freshwater and marine fishes. Here, we use genotype assignment between juvenile and larval yellow perch (Perca flavescens) from western Lake Erie to estimate and compare recruitment to the age-0 juvenile stage for larvae residing inside the highly turbid, south-shore Maumee River plume versus those occupying the less turbid, more …


Particle Backtracking Improves Breeding Subpopulation Discrimination And Natal-Source Identification In Mixed Populations, Michael E. Fraker, Eric J. Anderson, Reed M. Brodnik, Lucia Carreon-Martinez, Kristen M. Devanna, Brian J. Fryer, Daniel D. Heath, Julie M. Reichert, Stuart A. Ludsin Jan 2015

Particle Backtracking Improves Breeding Subpopulation Discrimination And Natal-Source Identification In Mixed Populations, Michael E. Fraker, Eric J. Anderson, Reed M. Brodnik, Lucia Carreon-Martinez, Kristen M. Devanna, Brian J. Fryer, Daniel D. Heath, Julie M. Reichert, Stuart A. Ludsin

Great Lakes Institute for Environmental Research Publications

We provide a novel method to improve the use of natural tagging approaches for subpopulation discrimination and source-origin identification in aquatic and terrestrial animals with a passive dispersive phase. Our method integrates observed site-referenced biological information on individuals in mixed populations with a particle-tracking model to retrace likely dispersal histories prior to capture (i.e., particle backtracking). To illustrate and test our approach, we focus on western Lake Erie's yellow perch (Perca flavescens) population during 2006-2007, using microsatellite DNA and otolith microchemistry from larvae and juveniles as natural tags. Particle backtracking showed that not all larvae collected near a presumed hatching …


Effect Of Cod: So42- Ratio, Hrt And Linoleic Acid Concentration On Mesophilic Sulfate Reduction: Reactor Performance And Microbial Population Dynamics, Chungman Moon, Rajesh Singh, Sathyanarayan S. Veeravalli, Saravanan R. Shanmugam, Subba Rao Chaganti, Jerald A. Lalman, Daniel D. Heath Jan 2015

Effect Of Cod: So42- Ratio, Hrt And Linoleic Acid Concentration On Mesophilic Sulfate Reduction: Reactor Performance And Microbial Population Dynamics, Chungman Moon, Rajesh Singh, Sathyanarayan S. Veeravalli, Saravanan R. Shanmugam, Subba Rao Chaganti, Jerald A. Lalman, Daniel D. Heath

Great Lakes Institute for Environmental Research Publications

Biological sulfate (SO42-) reduction was examined in anaerobic sequential batch reactors (ASBRs) operated under different hydraulic retention times (HRTs) ranging from 12 to 36 h and COD (Chemical Oxygen Demand)/SO42- ratios of 2.4, 1.6 and 0.8. Competition between SO42- reducing bacteria (SRBs), methane producing archaea (MPAs) and homoacetogens (HACs) was examined in controls and cultures treated with linoleic acid (LA). The ASBR performance was influenced by the COD/SO42- ratio in control cultures with a SO42- reduction of 87% at a COD/SO42- ratio of 0.8. At a 12 h HRT, in both control and LA treated cultures, greater than 75% SO42- …


The Effects Of Inbreeding On Sperm Quality Traits In Captive-Bred Lake Trout, Salvelinus Namaycush (Walbaum, 1972), K. Johnson, Ian A.E. Butts, J. L. Smith, C. C. Wilson, Trevor E. Pitcher Jan 2015

The Effects Of Inbreeding On Sperm Quality Traits In Captive-Bred Lake Trout, Salvelinus Namaycush (Walbaum, 1972), K. Johnson, Ian A.E. Butts, J. L. Smith, C. C. Wilson, Trevor E. Pitcher

Great Lakes Institute for Environmental Research Publications

The effects of inbreeding in both captive and wild-caught species and populations have been reported to affect a wide variety of life history traits. Recently, the effects of inbreeding on reproductive traits such as sperm quality have become a subject of particular interest for conservation biology, evolutionary ecology, and management of captive populations. This study investigated the effects of inbreeding on sperm quality in a captive population of experimentally inbred and outbred lake trout, Salvelinus namaycush. It was found for moderately to highly inbred males (males with half-sib and full-sib parents, respectively), that sperm quality traits (velocity, motility, linearity, longevity, …


Sperm Quality Of Hatchery-Reared Lake Trout Throughout The Spawning Season, Katelynn Johnson, Ian A.E. Butts, Chris C. Wilson, Trevor E. Pitcher Jan 2013

Sperm Quality Of Hatchery-Reared Lake Trout Throughout The Spawning Season, Katelynn Johnson, Ian A.E. Butts, Chris C. Wilson, Trevor E. Pitcher

Great Lakes Institute for Environmental Research Publications

The objective of this study was to investigate variation in sperm quality metrics (motility, velocity, linearity, longevity, and density) of hatchery-reared Lake Trout Salvelinus namaycush throughout the spawning season. Seasonal variation in sperm quality was investigated using both a regression and repeated-measures approach. Sperm was collected from the same 16 individuals over four sampling periods, separated by 3-week intervals. Regression analyses showed that 727% of the variation in sperm traits could be explained by seasonal variation, indicating that seasonality can have a significant impact on the quality of sperm. Significant positive linear relationships were found for percent motility and linearity …


Low Levels Of Extra-Pair Paternity In A Neotropical Duetting Songbird, The Rufous-And-White Wren (Thryothorus Rufalbus), Sarah B. Douglas, Daniel D. Heath, Daniel J. Mennill Jan 2012

Low Levels Of Extra-Pair Paternity In A Neotropical Duetting Songbird, The Rufous-And-White Wren (Thryothorus Rufalbus), Sarah B. Douglas, Daniel D. Heath, Daniel J. Mennill

Great Lakes Institute for Environmental Research Publications

Molecular analyses have confirmed that the majority of socially monogamous birds follow a genetically promiscuous reproductive strategy. Most such studies, however, have addressed species of the North Temperate Zone; tropical species are grossly underrepresented, although most of Earth's biodiversity is concentrated in the tropics. In this study, we describe the genetic mating strategy of the Rufous-and-white Wren (Thryothorus rufalbus), a socially monogamous duetting neotropical songbird. Over 8 years of studying a marked population in Costa Rica, we recorded genetic data from 51 broods. Microsatellite analysis of four variable loci revealed that the Rufous-and-white Wren follows a mixed reproductive strategy, where …


Juvenile Habitat Partitioning And Relative Productivity In Allochronically Isolated Sockeye Salmon (Oncorhynchus Nerka), E. K. Fillatre Miller, I. R. Bradbury, Daniel D. Heath Jan 2011

Juvenile Habitat Partitioning And Relative Productivity In Allochronically Isolated Sockeye Salmon (Oncorhynchus Nerka), E. K. Fillatre Miller, I. R. Bradbury, Daniel D. Heath

Great Lakes Institute for Environmental Research Publications

Allochronic divergence, like spatial isolation, may contribute to population diversity and adaptation, however the challenges for tracking habitat utilization in shared environments are far greater. Adult Klukshu River (Yukon, Canada) sockeye salmon, Oncorhynchus nerka, return as genetically distinct "early" and "late" runs. Early and late adult spawning populations (1999 and 2000) and their subsequent fry (sampled at 7 sites in 2000 and at 8 sites in 2001 throughout Klukshu Lake and River) were genotyped at eight microsatellite loci. Bayesian assignment was used to determine the spatial distribution of early versus late fry; although intermixed, the distribution of fry significantly differed …


Geographic Variation In Sperm Traits Reflects Predation Risk And Natural Rates Of Multiple Paternity In The Guppy, K. E. Elgee, J. P. Evans, I. W. Ramnarine, S. A. Rush, Trevor E. Pitcher Jan 2010

Geographic Variation In Sperm Traits Reflects Predation Risk And Natural Rates Of Multiple Paternity In The Guppy, K. E. Elgee, J. P. Evans, I. W. Ramnarine, S. A. Rush, Trevor E. Pitcher

Great Lakes Institute for Environmental Research Publications

Guppies (Poecilia reticulata) are models for understanding the interplay between natural and sexual selection. In particular, predation has been implicated as a major force affecting female sexual preferences, male mating tactics and the level of sperm competition. When predation is high, females typically reduce their preferences for showy males and engage more in antipredator behaviours, whereas males exploit these changes by switching from sexual displays to forced matings. These patterns are thought to account for the relatively high levels of multiple paternity in high-predation populations compared to low-predation populations. Here, we assess the possible evolutionary consequences of these patterns by …


Mate Choice For Nonadditive Genetic Benefits And The Maintenance Of Genetic Diversity In Song Sparrows, Bryan D. Neff, Trevor E. Pitcher Jan 2009

Mate Choice For Nonadditive Genetic Benefits And The Maintenance Of Genetic Diversity In Song Sparrows, Bryan D. Neff, Trevor E. Pitcher

Great Lakes Institute for Environmental Research Publications

The lek paradox asserts that strong directional selection via female choice should deplete additive genetic variation in fitness and consequently any benefit to females expressing the preference. Recently, we have provided a novel resolution to the paradox by showing that nonadditive genetic effects such as overdominance can be inherited from parent to offspring, and populations with females that express a mating preference for outbred males maintain higher genetic variation than populations with females that mate randomly. Here, we test our dynamic model using empirical data previously published from a small island population of song sparrows (Melospiza melodia). The model assumes …


An Introduction To Genetic Quality In The Context Of Sexual Selection, Trevor E. Pitcher, Herman L. Mays Jan 2008

An Introduction To Genetic Quality In The Context Of Sexual Selection, Trevor E. Pitcher, Herman L. Mays

Great Lakes Institute for Environmental Research Publications

This special issue of Genetica brings together empirical researchers and theoreticians to present the latest on the evolutionary ecology of genetic quality in the context of sexual selection. The work comes from different fields of study including behavioral ecology, quantitative genetics and molecular genetics on a diversity of organisms using different approaches from comparative studies, mathematical modeling, field studies and laboratory experiments. The papers presented in this special issue primarily focus on genetic quality in relation to ( 1) sources of genetic variation, ( 2) polyandry, ( 3) new theoretical developments and ( 4) comprehensive reviews.