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—Known morphological characteristics for identifying largemouth bass (top) and spotted bass (bottom) and used for comparison with genetic identification of fish in Lake Norman, North Carolina, 2007–2008 (scale is cm). Intermediate descriptions (from hybrids) also were developed for each trait depicted (Table 1).  

—Known morphological characteristics for identifying largemouth bass (top) and spotted bass (bottom) and used for comparison with genetic identification of fish in Lake Norman, North Carolina, 2007–2008 (scale is cm). Intermediate descriptions (from hybrids) also were developed for each trait depicted (Table 1).  

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Hybridization is common among many closely related fishes, such as the largemouth bass Micropterus salmoides and spotted bass M. punctulatus. Although these species are common members of the sport fish community in midwestern and southeastern U.S. reservoirs, fairly little is known about their ecological interactions or the potential for the introd...

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Context 1
... were used to raise the spinous dorsal fin for each photograph. Each fish was scored categorically using known differences in morphological characteristics (Table 1; Figures 1, 2) compiled from fish field identification books, scientific articles (Ramsey and Smitherman 1972;Pflieger 1975;Page and Burr 1991;Jenkins and Burkhead 1994;Rohde et al. 1996), and anecdotal information from field biologists. We also described potential intermediate morphological charac- teristics because some characteristics of hybrids may be co-dominant and hybrids may appear morphologically intermediate between largemouth bass and spotted bass, as has been observed in other hybrid centrarchids (Whitt et al. 1973). ...
Context 2
... 1). FIGURE 2.-Morphological characteristics (in addition to those displayed in Figure 1) for identifying juvenile largemouth bass (top) and spotted bass (bottom) and used for comparison with genetic identification of fish in Lake Norman, North Carolina, 2007. Spinous dorsal fin shape was also included because it was useful in the recommended model for juveniles. ...

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... Prior to 2008, if a fish could not be identified as an Alabama bass or largemouth bass through existing meristic identification methods, it was labeled as an Alabama bass x largemouth bass hybrid. In 2008, Godbout et al. (2009) developed a key for visually identifying hybrid black bass specifically in Lake Norman and this key was used for the remainder of our study. All black bass were measured for total length (TL, mm) and weighed (g). ...
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Lake Norman, North Carolina, has a popular fishery for largemouth bass (Micropterus salmoides), but in 2001, annual surveys by Duke Energy documented the unauthorized introduction of Alabama bass (M. henshalli). Concerns over the effects of this introduction on the existing largemouth bass fishery prompted this study, the objective of which was to use the existing standardized sampling program to document expansion of the Alabama bass population and describe changes in the population characteristics of largemouth bass in Lake Norman. Following Alabama bass introduction, the species quickly spread throughout the main channel of the reservoir, with a concomitant decline in largemouth bass abundance, although mean total length of largemouth bass increased. While the sampling protocol used was effective at documenting the changes in the main reservoir channel popula- tion characteristics between the two species, it did not document population characteristics in all areas of the reservoir. Additional samples collected in 2010 and 2013 by the North Carolina Wildlife Resources Commission in the upper area of the reservoir indicated that largemouth bass remained dominant in creek and cove areas but not along the main reservoir channel. This study illustrates that, while standardized sampling is a sound method for comparing black bass population characteristics between specific areas of interest, the addition of other habitat areas may be necessary to address specific questions regarding whole reservoir changes in their population characteristics. Further, this study serves as a cautionary tale of the unintend- ed consequences of illegal unauthorized introductions of non-native species on native congeners.
... are among the most popular freshwater sport fishes and as such have been the subject of numerous sanctioned and illegal translocations (Jackson 2002). These introductions have resulted in numerous hybridization events that confound species distributions and identification (Pipas and Bulow 1998;Godbout et al. 2009;Lewis et al. 2021). Although hybridization between the black basses does occur in nature, it is presumed to be a rare event (Hubbs 1955;Near et al. 2003) unless congeners come into secondary contact due to anthropogenic introductions (Morizot et al. 1991;Avise et al. 1997;Bangs et al. 2018;Taylor et al. 2018). ...
... Accurate and reliable identification of pure and hybrid individuals is key to monitoring populations and developing conservation and management strategies. Although phenotypic identification is commonly used as a practical way to manage fish populations, hybrids and backcrossed individuals often display phenotypes that resemble one parent over the other (Turner et al. 1991;Pierce and Van Den Avyle 1997;Pipas and Bulow 1998;Godbout et al. 2009), underscoring the need for genetic tools to quickly and reliably determine species identity and to quantify hybridization. To date, only one study has examined the accuracy of phenotypic identification in hybridizing populations of Alabama and Redeye bass (Lewis et al. 2021), and those authors reported that 100% of hybrids had been misidentified in the field. ...
... These similarities can be further amplified in later-generation crosses and backcrossed individuals. In addition, lateral line blotches can be affected by stress and ambient temperature, leading to differences in interpretation based on a fish's individual stress response and ambient conditions (Godbout et al. 2009;Baker et al. 2013). These cryptic phenotypes underscore the need for genetic tools to augment surveys of populations that are composed of Redeye and Alabama bass. ...
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Hybridization among the black basses (Micropterus spp.) occurs due to weak postzygotic reproductive barriers and anthropogenic factors such as habitat alteration. Introduction of previously allopatric species can also result in hybrid swarms and in some cases, extirpation of native species. Introgressive hybridization is a major conservation concern for the more range‐restricted black basses, which underscores the need for accurate identification of hybrids that often have cryptic phenotypes. To that end, we collected 1,723 fish from four river systems in the Mobile River Basin, Alabama, to compare phenotypic identification in the field based on morphology with genotype determined from single‐nucleotide polymorphism (SNP) analysis using diagnostic markers for black basses. Results indicate that phenotypic identification among these cryptic hybrids is only 11% accurate. Only 4% of the fish collected were identified as hybrids in the field, whereas genotype analysis classified 22% of fish as hybrids. The majority of those misidentified in the field were hybrids between Alabama Bass (M. henshalli) and Redeye Bass (M. coosae) or those species along with another black bass species. Hybrid individuals composed 5‐38% of the total number of fish collected from the four river systems, but 28‐68% were misidentified in each river system. These results underscore the need for genetic tools to augment classic field surveys in the black basses as cryptic hybridization may lead to errant management decisions based on inaccurate species distribution assessments.
... The results of this study warrant more frequent monitoring of Alabama's streams and rivers by using genetic tools. Hybrid individuals can present a great variety of phenotypes that range from closely resembling one parent species to a mixed morphology of both parents, with backcrossing events further complicating proper field identification (Godbout et al. 2009). A total of 62% of the fish collected for this study were misidentified based on phenotype-almost double the error rate recorded in another recent study of black bass hybridization in the Chattahoochee River system (Taylor et al. 2018). ...
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... A second observation of this species, at the same location on November 3, 2017, allowed DJFMP staff to collect specimens and further confirm the original species identification in a laboratory setting. However, external morphological traits are solely relied on, misidentification can sometimes occur because of the lack of distinctive traits between species, degradation of specimens, or the presence of interspecific hybrids (Godbout et al. 2009;Hull et al. 2010;Benjamin et al. 2018). In addition, it is unclear if this putative Bluefin Killifish observation constitutes the establishment of a new species in the estuary, given that even intentional species introductions have failed in the past (Dill and Cordone 1997). ...
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Biological invasion by non-native species has been identified as one of the major threats to native fish communities worldwide. The fish community of San Francisco Estuary is no exception, as the estuary has been recognized as one of the most invaded on the planet and the system has been impacted significantly by these invasions. Here, we summarize the introduction and probable establishment of a new species in the Sacramento–San Joaquin Delta, the Bluefin Killifish (Lucania goodei), as discovered by the US Fish and Wildlife Service Delta Juvenile Fish Monitoring Program (DJFMP). The DJFMP has conducted a large-scale beach seine survey since 1976, and it is the longest-running monitoring program in the San Francisco Estuary that extensively monitors the shallow-water nearshore habitat. Possibly introduced as discarded aquarium fish within the vicinity of the Delta Cross Channel, Bluefin Killifish is a close relative of the Rainwater Killifish (Lucania parva), another non-native fish species that has been present in the San Francisco Estuary system for decades. Studies in their native range suggest that Bluefin Killifish will fill a similar niche to Rainwater Killifish, albeit with a more freshwater distribution. The potential ecological impact of Bluefin Killifish remains unclear in the absence of additional studies. However, we have been able to track the spread of the species within the Sacramento–San Joaquin Delta through the existence of long-term monitoring programs. Our findings demonstrate the value of monitoring across various habitats for the early detection and proactive management of invasive species.
... Taken together, these results support the identification of all host species, with the possible exception of M. punctulatus. Given the presence of tooth patches on their tongues and mitochondrial association with M. salmoides, the M. punctulatus in our study are potentially hybrids (Godbout et al. 2009). ...
... These were also the only hosts whose species identification was not positively supported with genetic data. These individuals possessed tooth patches on their tongues and lower jaw lines not extending past their eyes, characters typical of M. punctulatus and hybrids, but rare in M. salmoides (Godbout et al. 2009). The presence of these characters and genetic identification of likely M. salmoides maternal ancestry and ambiguous paternal ancestry suggest that these fish are M. salmoides × M. punctulatus hybrids. ...
... If M. punctulatus utilize different habitats, prey on different organisms, etc. that are more similar to Lepomis spp., they could be more likely to be exposed to Posthodiplostomum sp. 3. However, given that both M. punctulatus and M. salmoides are ecologically similar and often co-occur (Godbout et al. 2009), it is likely that they are exposed to similar parasites, supporting an altered host physiology. Host-specificity of Diplostomatid metacercariae in fishes is the result of physiological compatibility restraints between hosts and parasites and there is growing support for the importance of this in other fish metacercariae (Locke et al. 2010;De León et al. 2016). ...
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Posthodiplostomum minimum utilizes a three-host life cycle with multiple developmental stages. The metacercarial stage, commonly known as ‘white grub’, infects the visceral organs of many freshwater fishes and was historically considered a host generalist due to its limited morphological variation among a wide range of hosts. In this study, infection data and molecular techniques were used to evaluate the host and tissue specificity of Posthodiplostomum metacercariae in centrarchid fishes. Eleven centrarchid species from three genera were collected from the Illinois portion of the Ohio River drainage and necropsied. Posthodiplostomum infection levels differed significantly by host age, host genera and infection locality. Three Posthodiplostomum spp. were identified by DNA sequencing, two of which were relatively common within centrarchid hosts. Both common species were host specialists at the genus level, with one species restricted to Micropterus hosts and the other preferentially infecting Lepomis . Host specificity is likely dictated by physiological compatibility and deviations from Lepomis host specificity may be related to host hybridization. Posthodiplostomum species also differed in their utilization of host tissues. Neither common species displayed strong genetic structure over the scale of this study, likely due to their utilization of bird definitive hosts.
... Nevertheless, a loss of reproductive output is an important issue for the ongoing conservation and management of Bluehead Suckers in the Bonneville basin, and its elucidation requires an accurate identification of both species and hybrids (Godbout et al. 2009). We provided a genetic tool for identification of hybrids and assessment of introgression. ...
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Habitat modification and introduced species are impacting native fishes in western North America, a situation now exacerbated by drought and anthropogenic water acquisition. One species of concern, the Bluehead Sucker Catostomus discobolus in the Bonneville basin of Utah, Idaho, and Wyoming, has experienced sharp population declines potentially augmented by hybridization with native Utah Sucker C. ardens. To evaluate this situation, we sequenced three diagnostic nuclear DNA loci and two mitochondrial genes across 81 Bluehead Suckers, 74 of which were collected in a basinwide genetic assessment and 7 from a targeted morphological evaluation. Combined, we detected 14 hybrids from the single site in the Bear River and the three sites in the Weber River that hosts the three largest remaining populations in the basin. All individuals sampled as putative hybrids were confirmed as F1 hybrids, ascertaining efficacy of field-based morphological identifications. Hybridization may be especially problematic for the numerically reduced Bluehead Sucker because it can further depress recruitment. However, no evidence of post-F1 backcrosses was found, suggesting in turn that hybrids are not reproducing, although the reasons for this are currently not understood. These results underscore the need to quantify the proportion of Bluehead Sucker recruitment lost to hybridization. Received January 6, 2016; accepted August 31, 2016
... Taken together, these results support the identification of all host species, with the possible exception of M. punctulatus. Given the presence of tooth patches on their tongues and mitochondrial association with M. salmoides, the M. punctulatus in our study are potentially hybrids (Godbout et al. 2009). ...
... These were also the only hosts whose species identification was not positively supported with genetic data. These individuals possessed tooth patches on their tongues and lower jaw lines not extending past their eyes, characters typical of M. punctulatus and hybrids, but rare in M. salmoides (Godbout et al. 2009). The presence of these characters and genetic identification of likely M. salmoides maternal ancestry and ambiguous paternal ancestry suggest that these fish are M. salmoides × M. punctulatus hybrids. ...
... If M. punctulatus utilize different habitats, prey on different organisms, etc. that are more similar to Lepomis spp., they could be more likely to be exposed to Posthodiplostomum sp. 3. However, given that both M. punctulatus and M. salmoides are ecologically similar and often co-occur (Godbout et al. 2009), it is likely that they are exposed to similar parasites, supporting an altered host physiology. Host-specificity of Diplostomatid metacercariae in fishes is the result of physiological compatibility restraints between hosts and parasites and there is growing support for the importance of this in other fish metacercariae (Locke et al. 2010;De León et al. 2016). ...
Conference Paper
White grub (Posthodiplostomum minimum centrarchi) is a juvenile strigeoid trematode that has been documented in many centrarchid fishes. It infects centrarchid fish by cercariae penetrating the skin, so transmission should be more efficient in slow moving water, and most studies are done on lentic systems where sunfish predominate. In this study, eleven centrarchid fish species (spotted bass (n=126), largemouth bass (n=18), smallmouth bass (n=8), bluegill (n=44), green sunfish (n=26), longear sunfish (n=50), orangespotted sunfish (n=36), redear sunfish (n=17), warmouth (n=13), black crappie (n=15), and white crappie (n=6)) were collected from the Ohio River Drainage in 2014 and 2015. Visceral organs were removed and examined for the presence of metacercariae. Prevalence of white grub ranged from 0 in white crappie to 100% in redear sunfish, and warmouth. Prevalence in bluegill, a common host, was 86.4%. Mean intensity of white grub ranged from one in black crappie to 231 in spotted bass. In order to compare white grub patterns among different species and size classes of centarchids, mass corrected density parameters were calculated using overall fish weight and individual organ weights. Preliminary genetic evidence suggests that there may be two species of white grub in this system, one in the genus Micropterus and one in the genus Lepomis.
... Taken together, these results support the identification of all host species, with the possible exception of M. punctulatus. Given the presence of tooth patches on their tongues and mitochondrial association with M. salmoides, the M. punctulatus in our study are potentially hybrids (Godbout et al. 2009). ...
... These were also the only hosts whose species identification was not positively supported with genetic data. These individuals possessed tooth patches on their tongues and lower jaw lines not extending past their eyes, characters typical of M. punctulatus and hybrids, but rare in M. salmoides (Godbout et al. 2009). The presence of these characters and genetic identification of likely M. salmoides maternal ancestry and ambiguous paternal ancestry suggest that these fish are M. salmoides × M. punctulatus hybrids. ...
... If M. punctulatus utilize different habitats, prey on different organisms, etc. that are more similar to Lepomis spp., they could be more likely to be exposed to Posthodiplostomum sp. 3. However, given that both M. punctulatus and M. salmoides are ecologically similar and often co-occur (Godbout et al. 2009), it is likely that they are exposed to similar parasites, supporting an altered host physiology. Host-specificity of Diplostomatid metacercariae in fishes is the result of physiological compatibility restraints between hosts and parasites and there is growing support for the importance of this in other fish metacercariae (Locke et al. 2010;De León et al. 2016). ...
Conference Paper
White grub (Posthodiplostomum minimum centrarchi) is a juvenile strigeoid trematode that has been documented in many centrarchid fishes. It was thought to be a generalist parasite infecting centrarchidae, but recent studies have suggested cryptic species. P. minimum infects fish by cercariae penetrating the skin. Transmission should be restricted to slow moving water, and most studies are done on lentic systems where sunfish predominate. In this study, ten centrarchid fish species (spotted bass(n=72), largemouth bass(n=3), bluegill(n=18), green sunfish(n=7), longear sunfish(n=10), orangespotted sunfish(n=4), redear sunfish(n=5), warmouth(n=6), black crappie (n=8), white crappie(n=1)) were collected from the Wabash River and Ohio River Drainage in 2014. Visceral organs, including reproductive tracts, were removed and examined for the presence of metacercariae. Prevalence of white grub ranged from 0 in black crappie, green sunfish, and white crappie to 100% in largemouth bass, redear sunfish, and warmouth. Prevalence in bluegill, a common host, was 77.8%. Mean intensity of white grub ranged from 3.5 in longear sunfish to 950 in largemouth bass. White grub was found in approximately 50% of below stock spotted bass (<18cm) and near 100% of stock (18-28cm), and quality size bass (>28cm) (length categories based on percentages of world record lengths rather than strictly by age). Intensity increased with size as well in spotted bass but variation was very high in stock size bass, which included multiple age classes. Spotted bass are commonly found in flowing water, and should be somewhat protected from infection. The parasitism rate jump in stock class may reflect a life history event such as moving to spawning in slack water where they are exposed to higher transmission rates. Preliminary evidence suggests that there may be 2 populations of white grub in this system, 1 in the genus Micropterus and 1 in the genus Lepomis.
... Hybridization between Largemouth Bass and Spotted Bass has been reported from Lake Norman, North Carolina (Godbout et al. 2009). There is a widely held popular belief that such hybridizations occur throughout the southeastern United States (e.g., ...
... Owen 2012); however, such hybridization is not often mentioned in the literature (e.g., Trautman 1981;Godbout et al. 2009), and has not been reported in Arkansas. Robison and Buchanan (1988) distinguished the Largemouth Bass from the other black basses on the basis of the upper jaw extending backward well beyond the eye, a large deep notch being present between the spinous and soft dorsal fins, and the spinous and soft dorsal fins being only barely connected by a membrane. ...
... In comparison the jaw of the Spotted Bass stops approximately in line with the eye, has only a shallow notch, and in the young, develops a black spot at the base of the caudal fin (Robison and Buchanan 1988). Godbout et al. (2009) presented in tree form several characters for the discrimination between Largemouth and Spotted Bass adults and juveniles, as well as their hybrids. In the following dichotomous key adapted from Godbout et al. (2009), traits were selected on the basis of perfect discrimination between Largemouth and Spotted Bass, although use of this key would identify some hybrid bass as either largemouth or spotted. ...
Thesis
Full-text available
Largemouth Bass are top predators in many lakes in Arkansas, making them ecologically important and a species of management concern. Additionally, Largemouth Bass Micropterus salmoides is the most important sportfish economically in Arkansas, receiving about 40% of the fishing effort from the state’s $517 million recreational fishery. Approximately 50% of the fishing effort is directed at the Arkansas River, where previous work at the University of Arkansas at Pine Bluff (UAPB) has demonstrated that recruitment, growth, and ultimately year-class strength, were related to the hydrology of that major waterway. However, little previous work has explored the recruitment dynamics of Largemouth Bass in other systems that experience relatively little hydrologic change over the course of the year. These other systems receive the remainder of the fishing effort for Largemouth Bass. Understanding the recruitment dynamics of Largemouth Bass in Arkansas lakes will assist the Arkansas Game and Fish Commission (AGFC) in more effectively managing Largemouth Bass sport fisheries outside of the Arkansas River system. To better understand the processes by which the strength of a Largemouth Bass year-classes is determined, this study took a detailed look at the 2013 cohort of Largemouth Bass (termed “juvenile”) from eight (8) representative lakes in southeastern Arkansas. Lakes ranged in size from 80-688 ha, and consisted of either man-made impoundments or old oxbow lakes that had been disconnected from their parent river by mainline levees. Eight (8) cycles of fish collections were completed between May 2013 and May 2014 on each lake, allowing detailed analysis of juvenile Largemouth Bass populations during the summer, fall, and winter of their first year of life (i.e., as age 0) and the spring of their second year (i.e., age 1). Adult and juvenile Largemouth Bass were collected by boat-mounted electrofishing during each cycle. Adult bass were always measured and released, while samples of juvenile Largemouth Bass were retained during the summer sampling cycles. During each sampling cycle, water quality parameters were recorded using a portable Hydrolab multi-probe field unit. Lake areas, perimeters, and depth profiles were determined for each lake through either bathymetric mapping or inspection of satellite imagery. Retained juvenile Largemouth Bass were dissected to examine stomach contents and extract otoliths from a subsample of the fish returned to UAPB. Hatching date was determined from bass in which otoliths were extracted. Logistic regression was used to determine the age and total length at which stomach contents were more likely to contain fish than invertebrates, a key life history determinant of bass populations in classical models. Using the catch-per-unit-effort (CPUE) of adult and juvenile Largemouth Bass to represent relative “stock” and “recruit” abundances, the quality of fit for standard recruit-stock models was assessed on time scales ranging from 1-12 months postspawning. Three datasets were produced combining physical and water quality parameters, quantitative life history information, and CPUE data. These data sets were subjected to exhaustive subset regression to identify possible quantitative models for Largemouth Bass year-class strength in July and October of the age-0 year, and May of the age-1 year. The frequency at which different classes of explanatory variables entered the top or best-fitting models (as selected by AIC) for each period was inspected to ascertain which factors had the most influence on the abundance of the Largemouth Bass year-classes. Assessment of the adult Largemouth Bass populations that occurred in May 2013 suggested that two of the study lakes were “bass crowded” according to conventional small-impoundment management guidelines; populations from the other lakes would have been considered optimum or “balanced.” Boat-mounted electrofishing proved ineffective for capturing juvenile Largemouth Bass less than 20 d old or smaller than 25-mm TL. Electrofishing also was remarkably ineffective in collecting juvenile Largemouth Bass during January-February 2014, presumably due to low water temperatures and ice cover. Length-frequency analyses suggested juvenile Largemouth Bass exhibited some overwinter growth in half of the study lakes, though discriminating overwinter growth from overwinter size-selective mortality was not possible. Standard recruit-stock models suggested that the adult Largemouth Bass abundance was most important in predicting the size or strength of the age-0 year-class during the mid-summer and fall of 2013. Recruit-stock models failed to explain juvenile Largemouth Bass abundance during the early summer of 2013 (when bass were 2-4 weeks old) or spring of 2014 (when juvenile bass were 11-12 months old). The recruitstock model developed for Largemouth Bass in these lakes by mid-summer, remained intact through fall, but decoupled by the following spring. Overall, analyses suggested a probable recruitment bottleneck for Largemouth Bass in southeastern Arkansas lakes occurring during winter. Additional exploratory analysis did not support that broad linkages existed between life-history stages, as suggested by prevailing conceptual models. Future research and management effort should be directed at identifying and possibly mitigating factors that contribute to overwinter mortality of juvenile Largemouth Bass.
... Taken together, these results support the identification of all host species, with the possible exception of M. punctulatus. Given the presence of tooth patches on their tongues and mitochondrial association with M. salmoides, the M. punctulatus in our study are potentially hybrids (Godbout et al. 2009). ...
... These were also the only hosts whose species identification was not positively supported with genetic data. These individuals possessed tooth patches on their tongues and lower jaw lines not extending past their eyes, characters typical of M. punctulatus and hybrids, but rare in M. salmoides (Godbout et al. 2009). The presence of these characters and genetic identification of likely M. salmoides maternal ancestry and ambiguous paternal ancestry suggest that these fish are M. salmoides × M. punctulatus hybrids. ...
... If M. punctulatus utilize different habitats, prey on different organisms, etc. that are more similar to Lepomis spp., they could be more likely to be exposed to Posthodiplostomum sp. 3. However, given that both M. punctulatus and M. salmoides are ecologically similar and often co-occur (Godbout et al. 2009), it is likely that they are exposed to similar parasites, supporting an altered host physiology. Host-specificity of Diplostomatid metacercariae in fishes is the result of physiological compatibility restraints between hosts and parasites and there is growing support for the importance of this in other fish metacercariae (Locke et al. 2010;De León et al. 2016). ...
Conference Paper
Little information is available regarding the demographics of spotted bass, Micropterus punctulatus, within lotic systems along their northern boundary. We sought to assess the population of spotted bass in the Wabash River using pulsed DC electrofishing over a two year period. Average density as measured by CPUE was significantly higher in 2013 compared to 2014. Whereas the average minimum length sampled both years was similar, the length frequency distributions were significantly different between years. The proportional size distribution was different between years with 2013 showing a greater proportion of stock and quality sized fish. The proportion of preferred fish was low and no fish were of memorable size for either year. In 2013 and 2014, a sample of the population was necropsied to assess white grub, Posthodiplostomum minimum centrarchi, burdens within the body cavity. In 2013, white grub was found to be present in 76% of the 46 individuals examined. To date, white grub has been found in 51% of the 27 individuals necropsied in 2014. Spotted bass of the stock, quality, and preferred size distributions exhibited a prevalence of white grub near 100% for both years, while fish below stock length showed a prevalence below 50% for each year. Although recreationally used, the population of Spotted Bass in the Wabash River is comprised of a low density of small individuals in relatively good condition.