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Lance T Yonkos - One of the best experts on this subject based on the ideXlab platform.
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nonlethal laparoscopic detection of intersex testicular oocytes in Largemouth Bass micropterus salmoides and smallmouth Bass micropterus dolomieu
Environmental Toxicology and Chemistry, 2017Co-Authors: Alexander H Macleod, Vicki S. Blazer, Mark A Matsche, Lance T YonkosAbstract:Intersex in wild fish populations has received considerable attention in the scientific literature and public media. Conventional detection of testicular oocytes, the presence of immature oocytes within testis of male fish, commonly employs transverse sectioning of excised testis and is lethal. The present study used a nonlethal laparoscopic technique to collect biopsies of testis from black Bass, entering the body cavity via the genital pore. Detection of testicular oocytes was compared between biopsy and conventional methods using 79 smallmouth Bass (Micropterus dolomieu) from 8 sites and 68 Largemouth Bass (Micropterus salmoides) from 4 sites. The 2 methods performed similarly at sites where testicular oocyte severity was moderate or high (6 of 8 smallmouth Bass sites), whereas transverse sectioning resulted in superior testicular oocyte detection at sites where severity was low (2 of 8 smallmouth Bass sites and all 4 Largemouth Bass sites). In smallmouth Bass, testicular oocyte prevalence by transverse and biopsy methods was strongly correlated across sites (r2 = 0.81) and severity reported by enumeration of testicular oocytes was moderately correlated across sites (r2 = 0.59). Survival of a subset of Largemouth Bass (n = 20) to 28 d after laparoscopic surgery was 90%. The present research indicates that laparoscopy may be useful for monitoring the prevalence and severity of testicular oocytes in Micropterus species, particularly when lethal sampling is precluded. Environ Toxicol Chem 2017;36:1924-1933. © 2016 SETAC.
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intersex testicular oocytes in Largemouth Bass micropterus salmoides on the delmarva peninsula usa
Environmental Toxicology and Chemistry, 2014Co-Authors: Lance T Yonkos, Elizabeth A Friedel, Daniel J FisherAbstract:The authors describe the prevalence and severity of intersex in the form of testicular oocytes in Largemouth Bass (Micropterus salmoides) collected over a 5-yr period from a variety of surface waters on the Delmarva Peninsula, USA, a region dominated by poultry production and agricultural land use. During a survey from 2005 to 2007 of approximately 200 male specimens representing 6 fish and 2 frog species collected from numerous small-order streams on Delmarva, intersex was observed in only Largemouth Bass (system-wide prevalence 17%). During 2008 and 2009, testicular oocytes were encountered in male Largemouth Bass from 6 lakes and 1 large river system, with prevalence ranging from 33% to 88% (weighted arithmetic mean, 57%). The prevalence of testicular oocytes in Largemouth Bass from Delmarva lakes was comparable to the highest levels reported in a national US Geological Survey reconnaissance of this species, which also occurred in regions of the Atlantic coastal plain with intensive row-crop and animal agriculture. To the authors' knowledge, the present study represents the first report in the peer-reviewed scientific literature of testicular oocytes in fish on the Delmarva Peninsula. Environ Toxicol Chem 2014;33:1163–1169. © 2014 SETAC
Kelly L Weinersmith - One of the best experts on this subject based on the ideXlab platform.
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diets of Largemouth Bass micropterus salmoides in the sacramento san joaquin delta
San Francisco Estuary and Watershed Science, 2019Co-Authors: Kelly L Weinersmith, Denise D Colombano, Andrew J Bibian, Matthew J Young, A Sih, Louise J ConradAbstract:Author(s): Weinersmith, Kelly L.; Colombano, Denise D.; Bibian, Andrew J.; Young, Matthew J.; Sih, Andew; Conrad, J. Louise | Abstract: Largemouth Bass (Micropterus salmoides) were introduced into the Sacramento-San Joaquin Delta (the Delta) over 100 years ago. In the last 2 decades, the abundance of centrarchids (including Largemouth Bass) in the littoral zone has increased, while some native fish and fish that were previously abundant in the pelagic zone have declined. Largemouth Bass are now one of the most abundant piscivores in the Delta. Understanding the ecology of this top predator — including a comprehensive understanding of what prey are important in Largemouth Bass diets — is important to understanding how this species may affect the Delta fish community. To address this need, we conducted electrofishing surveys of Largemouth Bass at 33 sites every 2 months from 2008 to 2010, measuring fish fork lengths and collecting stomachs contents at each site. We characterized diets using Percent Index of Relative Importance for 3,004 Largemouth Bass, with samples that spanned all seasons. Amphipods dominated the diets of Largemouth Bass ≤175 mm FL year-round, with dipterans, odonates, and copepods and cladocerans representing other important diet items. Non-native red swamp crayfish (Procambarus clarkii) were the most important prey for Largemouth Bass g175 mm FL. Non-native centrarchids (including Largemouth Bass) and amphipods were important prey items as well. Prickly Sculpin (Cottus asper) were the most frequently consumed native fish. Other native fish and pelagic fish species rarely occurred in Largemouth Bass diets, and we discuss trends in how the frequency of co-occurrence of these fishes with Largemouth Bass in the electrofishing surveys was associated with their frequency in Largemouth Bass diets. The Largemouth Bass in the Delta appear to be sustained largely on a diet of other non-natives that reside in the littoral zone.
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effects of turbidity and an invasive waterweed on predation by introduced Largemouth Bass
Environmental Biology of Fishes, 2014Co-Authors: Kelly L Weinersmith, Matthew J Young, Louise J Conrad, Maud C O Ferrari, Lynn Ranaker, Andrew SihAbstract:Anthropogenic activities lead to changes in characteristics of aquatic ecosystems, including alteration of turbidity and addition of invasive species. In this study, we tested how changes in turbidity and the recent invasion of an aquatic macrophyte, Egeria densa, may have changed the predation pressure by introduced Largemouth Bass on juvenile striped Bass and delta smelt, two species that have seen a drastic decline in recent decades in the Sacramento-San Joaquin Delta. In a series of mesocosm experiments, we showed that increases in vegetation density decreased the predation success of Largemouth Bass. When placed in an environment with both open water and vegetated areas, and given a choice to forage on prey associated with either of these habitats, Largemouth Bass preyed mainly on open water species as opposed to vegetation-associated species, such as juvenile Largemouth Bass, bluegill or red swamp crayfish. Finally, we showed that turbidity served as cover to open water species and increased the survival of delta smelt, an endemic species at risk. We also found that such open water prey tend not to seek refuge in the vegetation cover, even in the presence of an imminent predation threat. These results provide the beginning of a mechanistic framework to explain how decreases in turbidity and increases in vegetation cover correlate with a decline of open water species in the Sacramento-San Joaquin Delta.
Louise J Conrad - One of the best experts on this subject based on the ideXlab platform.
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diets of Largemouth Bass micropterus salmoides in the sacramento san joaquin delta
San Francisco Estuary and Watershed Science, 2019Co-Authors: Kelly L Weinersmith, Denise D Colombano, Andrew J Bibian, Matthew J Young, A Sih, Louise J ConradAbstract:Author(s): Weinersmith, Kelly L.; Colombano, Denise D.; Bibian, Andrew J.; Young, Matthew J.; Sih, Andew; Conrad, J. Louise | Abstract: Largemouth Bass (Micropterus salmoides) were introduced into the Sacramento-San Joaquin Delta (the Delta) over 100 years ago. In the last 2 decades, the abundance of centrarchids (including Largemouth Bass) in the littoral zone has increased, while some native fish and fish that were previously abundant in the pelagic zone have declined. Largemouth Bass are now one of the most abundant piscivores in the Delta. Understanding the ecology of this top predator — including a comprehensive understanding of what prey are important in Largemouth Bass diets — is important to understanding how this species may affect the Delta fish community. To address this need, we conducted electrofishing surveys of Largemouth Bass at 33 sites every 2 months from 2008 to 2010, measuring fish fork lengths and collecting stomachs contents at each site. We characterized diets using Percent Index of Relative Importance for 3,004 Largemouth Bass, with samples that spanned all seasons. Amphipods dominated the diets of Largemouth Bass ≤175 mm FL year-round, with dipterans, odonates, and copepods and cladocerans representing other important diet items. Non-native red swamp crayfish (Procambarus clarkii) were the most important prey for Largemouth Bass g175 mm FL. Non-native centrarchids (including Largemouth Bass) and amphipods were important prey items as well. Prickly Sculpin (Cottus asper) were the most frequently consumed native fish. Other native fish and pelagic fish species rarely occurred in Largemouth Bass diets, and we discuss trends in how the frequency of co-occurrence of these fishes with Largemouth Bass in the electrofishing surveys was associated with their frequency in Largemouth Bass diets. The Largemouth Bass in the Delta appear to be sustained largely on a diet of other non-natives that reside in the littoral zone.
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effects of turbidity and an invasive waterweed on predation by introduced Largemouth Bass
Environmental Biology of Fishes, 2014Co-Authors: Kelly L Weinersmith, Matthew J Young, Louise J Conrad, Maud C O Ferrari, Lynn Ranaker, Andrew SihAbstract:Anthropogenic activities lead to changes in characteristics of aquatic ecosystems, including alteration of turbidity and addition of invasive species. In this study, we tested how changes in turbidity and the recent invasion of an aquatic macrophyte, Egeria densa, may have changed the predation pressure by introduced Largemouth Bass on juvenile striped Bass and delta smelt, two species that have seen a drastic decline in recent decades in the Sacramento-San Joaquin Delta. In a series of mesocosm experiments, we showed that increases in vegetation density decreased the predation success of Largemouth Bass. When placed in an environment with both open water and vegetated areas, and given a choice to forage on prey associated with either of these habitats, Largemouth Bass preyed mainly on open water species as opposed to vegetation-associated species, such as juvenile Largemouth Bass, bluegill or red swamp crayfish. Finally, we showed that turbidity served as cover to open water species and increased the survival of delta smelt, an endemic species at risk. We also found that such open water prey tend not to seek refuge in the vegetation cover, even in the presence of an imminent predation threat. These results provide the beginning of a mechanistic framework to explain how decreases in turbidity and increases in vegetation cover correlate with a decline of open water species in the Sacramento-San Joaquin Delta.
Steven J Cooke - One of the best experts on this subject based on the ideXlab platform.
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potential consequences of angling on nest site fidelity in Largemouth Bass
Environmental Biology of Fishes, 2017Co-Authors: William M Twardek, Aaron D Shultz, Julie E Claussen, Steven J Cooke, Jeffrey A Stein, Jeffrey B Koppelman, Frank J S Phelan, David P PhilippAbstract:Breeding site fidelity has evolved in many vertebrate taxa, suggesting both that site selection has an important influence on fitness potential and that the decision to reuse a nesting site is related to the individual’s prior nesting success at that location. For a species that provides parental care, such as the Largemouth Bass Micropterus salmoides, catch-and-release angling impacts individual nesting success and fitness through physiological disturbance and by removing the nest-guarding male from its brood, thereby allowing temporary access to eggs and hatchlings by brood predators. To assess the impact of catch-and-release angling on nest site fidelity, we compared the consequences of angling on individually marked (i.e., with passive integrated transponders) nest-guarding male Largemouth Bass in Ontario. An extremely high degree of nest site fidelity in year two was observed for males that were angled only once during year one (87% within 10 m of the previous year’s nest), 96.7% of which remained on the nest and completed parental care activities. There was significantly lower fidelity in year two, however, for males that were angled multiple times during year one (27% within 10m of the previous year’s nest), only 5.6% of which remained on the nest and completed parental care activities. This observed difference suggests that angling nesting Bass may cause them to avoid previously used nest sites and instead search for alternative sites during future reproductive seasons. This human-induced impact on nest site choice may impact the future reproductive success of those Largemouth Bass.
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size dependent consequences of exogenous cortisol manipulation on overwinter survival and condition of Largemouth Bass
Journal of Experimental Zoology, 2017Co-Authors: Jonathan D Midwood, David H. Wahl, Kathryn S Peiman, Aja E W Burt, Mohammed Yusuf Sarker, Michael A Nannini, Steven J CookeAbstract:Little is known about the size-dependent consequences of stressors on wild animals, which is particularly relevant during winter where size-specific trends in survival are common. Here, exogenous cortisol manipulation was used to investigate the effect of a physiological challenge on overwinter mortality and spring condition of Largemouth Bass (Micropterus salmoides) across a range of body sizes. Fish were wild-caught in the fall, assigned into either control or cortisol manipulated treatments, and held in replicated experimental ponds. For Bass that survived the winter, length, mass, and health metrics (e.g., gonadosomatic index [GSI], hepatosomatic index [HSI], and water content) were determined in the spring. Winter survival was marginally lower for cortisol treated Bass; however, there was no influence of initial length, mass, or condition on overwinter survival. When Bass were grouped by size, survival was significantly higher for Bass 300-350 mm in length compared to those <200 mm. The treatment did not strongly influence spring health metrics, suggesting that Largemouth Bass that survived the winter were able to recover from the effects of the cortisol elevation. Initial size and sex were linked to some spring health metrics, with large females having the highest GSI and HSI scores. Overall, results from this study do not support the notion that there are size-dependent responses to cortisol manipulation in a teleost fish. Rather, this type of physiological challenge may modulate the natural rates of winter mortality that are primarily driven by starvation and predation, independent of body size, in subadult and adult Largemouth Bass.
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fisheries induced evolution in Largemouth Bass linking vulnerability to angling parental care and fitness
2015Co-Authors: David P Philipp, David H. Wahl, Julie E Claussen, Steven J Cooke, Jeffrey A Stein, Jeffrey B Koppelman, Cory D. Suski, David Sutter, Robert ArlinghausAbstract:—Long-term studies in Ontario, Canada on Largemouth Bass Micropterus salmoides and Smallmouth Bass M. dolomieu have demonstrated that angling nesting males (both catch and harvest and catch and release) can have negative impacts on the reproductive success for the captured individual. They have also demonstrated that within a population, the male Bass that provide the best and longest parental care for their offspring are the most capable of having the greatest relative contribution to the year-class. Furthermore, those males are also the most aggressive toward potential brood predators and, hence, the most vulnerable to angling. Based on those relationships, we postulated that angling in general, and especially angling for nesting Bass, results in selection against aggressive individuals in a population, and as a result, the angled population evolves to become less aggressive, containing males with diminished parental care attributes, an example of fisheries-induced evolution (FIE). We recognize, however, that some change towards less aggressive behaviors may also result from learning and phenotypic plasticity. Controlled, long-term selective breeding experiments over 30+ years have, however, documented the heritability of vulnerability of Bass to angling and, hence, the potential for selection to act on that trait. Reproductive competition experiments further demonstrated that the highly vulnerable strain of Bass produced in those selective breeding experiments indeed had greater reproductive success than the less vulnerable strain. Because angling for Largemouth Bass has been occurring for decades, we also postulated that there should be some evidence in the wild of this FIE. In fact, we did find that the level of vulnerability to angling of nesting male Largemouth Bass in lakes that have had little to no exploitation was significantly greater than that observed for nesting males in moderately and heavily angled populations.
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the influence of water temperature and accelerometer determined fight intensity on physiological stress and reflex impairment of angled Largemouth Bass
Conservation Physiology, 2014Co-Authors: Jacob W Brownscombe, Kelsey Marchand, Kathryn Tisshaw, Victoria Fewster, Olivia Groff, Melissa Pichette, Marian Seed, Lee F G Gutowsky, Alexander D M Wilson, Steven J CookeAbstract:Release of fish captured by recreational anglers is a common practice due to angler conservation ethics or compliance with fisheries regulations. As such, there is a need to understand the factors that influence mortality and sub-lethal impairments to ensure that catch-and-release angling is a sustainable practice. Longer angling times generally contribute to increased stress and mortality in fish such that reducing these times putatively reduces stress and improves survival. However, the relative importance of fight intensity (rather than simply duration) on fish condition is poorly understood. The objective of this research was to examine the effects of fight intensity on physiological stress and reflex impairment of Largemouth Bass (Micropterus salmoides). The Largemouth Bass were angled using conventional recreational fishing gear in May (water temperature ∼12°C) and June (∼22°C) of 2014 in Lake Opinicon, Ontario, Canada. Fight intensity was quantified using tri-axial accelerometer loggers mounted on the tips of fishing rods. Upon capture, reflex impairment measures were assessed, and fish were held for 1 h prior to blood sampling for measurement of physiological stress (blood glucose and lactate concentrations and pH). Physiological stress values showed a negative trend with fight duration and total fight intensity, but a positive trend with average fight intensity. Water temperature emerged as the most important predictor of the stress response in Largemouth Bass, while fight duration and intensity were not strong predictors. Reflex impairment was minimal, but higher reflex impairment scores were associated with elevated blood glucose. Overall, the findings of this study suggest that angling for Largemouth Bass at colder temperatures ( 20°C). Based on our findings, we conclude that fight intensity is likely not to be a major driver of physiological stress in this species using typical Largemouth Bass angling gear, owing to the relatively short fight times (i.e. <2 min).
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selection for vulnerability to angling in Largemouth Bass
Transactions of The American Fisheries Society, 2009Co-Authors: David P Philipp, Julie E Claussen, Steven J Cooke, Jeffrey B Koppelman, Cory D. Suski, Dale P BurkettAbstract:Abstract Although a great deal of effort has been expended to try to understand the consequences of fishing-induced selection by commercial fisheries, relatively little effort has been put into trying to understand the selective effects of recreational angling. We conducted a long-term selection experiment to assess the heritability of vulnerability to angling in Largemouth Bass Micropterus salmoides. Three successive generations of artificially selected Largemouth Bass were produced from a single experimental study population. Within each generation, individual adult Largemouth Bass were identified as having either high or low vulnerability to angling through a series of controlled catch-and-release angling trials. Individuals of each vulnerability group (high and low) were then selected from that population for breeding to produce the next generation. The response to selection for vulnerability to angling increased with each generation; that is, the magnitude of the difference between the high- and low-...
Mohamed Faisal - One of the best experts on this subject based on the ideXlab platform.
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laboratory investigation into the role of Largemouth Bass virus ranavirus iridoviridae in smallmouth Bass mortality events in pennsylvania rivers
BMC Veterinary Research, 2018Co-Authors: Traimat Boonthai, Thomas P. Loch, Geoffrey D. Smith, Andrew D. Winters, Matti Kiupel, Travis O. Brenden, Mohamed Faisal, Coja YamashitaAbstract:Mortality episodes have affected young-of-year smallmouth Bass (Micropterus dolomieu) in several river systems in Pennsylvania since 2005. A series of laboratory experiments were performed to determine the potential role of Largemouth Bass virus (Ranavirus, Iridoviridae) in causing these events. Juvenile smallmouth Bass experimentally infected with the Largemouth Bass virus exhibited internal and external clinical signs and mortality consistent with those observed during die-offs. Microscopically, infected fish developed multifocal necrosis in the mesenteric fat, liver, spleen and kidneys. Fish challenged by immersion also developed severe ulcerative dermatitis and necrotizing myositis and rarely panuveitis and keratitis. Largemouth Bass virus-challenged smallmouth Bass experienced greater mortality at 28 °C than at 23 or 11 °C. Co-infection with Flavobacterium columnare at 28 °C resulted in significant increase in mortality of smallmouth Bass previously infected with Largemouth Bass virus. Aeromonas salmonicida seems to be very pathogenic to fish at water temperatures < 23 °C. While co-infection of smallmouth Bass by both A. salmonicida and Largemouth Bass virus can be devastating to juvenile smallmouth Bass, the optimal temperatures of each pathogen are 7–10 °C apart, making their synergistic effects highly unlikely under field conditions. The sum of our data generated in this study suggests that Largemouth Bass virus can be the causative agent of young-of-year smallmouth Bass mortality episodes observed at relatively high water temperature.
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Laboratory investigation into the role of Largemouth Bass virus (Ranavirus, Iridoviridae) in smallmouth Bass mortality events in Pennsylvania rivers
BMC, 2018Co-Authors: Traimat Boonthai, Thomas P. Loch, Coja J. Yamashita, Geoffrey D. Smith, Andrew D. Winters, Matti Kiupel, Travis O. Brenden, Mohamed FaisalAbstract:Abstract Background Mortality episodes have affected young-of-year smallmouth Bass (Micropterus dolomieu) in several river systems in Pennsylvania since 2005. A series of laboratory experiments were performed to determine the potential role of Largemouth Bass virus (Ranavirus, Iridoviridae) in causing these events. Results Juvenile smallmouth Bass experimentally infected with the Largemouth Bass virus exhibited internal and external clinical signs and mortality consistent with those observed during die-offs. Microscopically, infected fish developed multifocal necrosis in the mesenteric fat, liver, spleen and kidneys. Fish challenged by immersion also developed severe ulcerative dermatitis and necrotizing myositis and rarely panuveitis and keratitis. Largemouth Bass virus-challenged smallmouth Bass experienced greater mortality at 28 °C than at 23 or 11 °C. Co-infection with Flavobacterium columnare at 28 °C resulted in significant increase in mortality of smallmouth Bass previously infected with Largemouth Bass virus. Aeromonas salmonicida seems to be very pathogenic to fish at water temperatures
