Etheostoma Flabellare Research Articles

Diet of the endemic Kanawha darter (Etheostoma kanawhae) including comparisons with sympatric fantail darters (Etheostoma flabellare)

Diet of the endemic Kanawha darter (Etheostoma kanawhae) including comparisons with sympatric fantail darters (Etheostoma flabellare)

Response to MHC-based olfactory cues in a mate choice context in two species of darter (Percidae: Etheostoma).

Mate choice is hypothesized to play an important role in maintaining high diversity at major histocompatibility complex (MHC) genes in vertebrates. Many studies have revealed that females across taxa prefer the scent of males with MHC genotypes different to their own. In this study we tested the "opposites-attract" hypothesis in two species of darter with known differences in female criteria used in mate choice: in the fantail darters (a paternal-care species), females prefer males with visual traits related to nest guarding and egg tending, while in rainbow darters (not a paternal-care species) female mate choice criteria are unknown. In dichotomous mate-choice trials, we presented females of both species with the scents of conspecific males with MHC class IIb genotypes that were either similar or dissimilar to that of the focal female. We evaluated the proportion of time each female spent with each male and calculated the average strength of female preference for both species. Female fantail darters demonstrated a preference for the scent of males with similar (rather than dissimilar) MHC genotypes, but this result was not statistically significant. Rainbow darter females showed no preference for the scent of males with similar or dissimilar MHC genotypes. Our results do not support the "opposites-attract" hypothesis in darters.

Nuclear microRNAs may regulate mitochondrial gene expression following effluent exposure in darter (Etheostoma) species.

Wastewater effluent is a metabolic stressor to aquatic organisms, though the mechanisms regulating metabolic rate in fish are not fully understood. Changes in metabolism may be regulated by microRNA (miRNA), small RNA molecules that post-transcriptionally regulate target mRNA translation in fish. Nuclear encoded miRNA are present in mammalian mitochondria where they regulate translation of mitochondrial genes, namely subunits for oxidative phosphorylation complexes; though this mechanism has not been identified in fish. This study aimed to identify if miRNA are present in darter (Etheostoma spp.) mitochondria, and if the metabolic stress occurring in darters in the Grand River, Waterloo, is partly regulated by miRNAs supressing translation of target mitochondrial genes. Three species of darters (E. caeruleum; E. nigrum; E. flabellare) were collected from upstream and downstream of the Waterloo wastewater treatment plant, and qPCR analysis confirmed the presence of four miRNA bioinformatically predicted to target mitochondrial mRNAs within the mitochondria, namely let-7a, miR-1, miR-122 and miR-20. E. caeruleum collected from downstream had lower cytochrome c oxidase activity, with a respective higher miR-1 abundance in the mitochondria, while E. nigrum had both a higher miR-20 abundance and cytochrome c oxidase activity downstream. E. flabellare was the only species that exhibited a lower miR-122 abundance downstream, despite no difference in cytochrome c oxidase activity between sites. Overall, this study confirmed the presence of miRNA within the mitochondria of daters, predicted a relationship between miR-1, and miR-20 abundance and cytochrome c oxidase activity, and identified one sex-specific miRNA, miR-20.

Factors associated with distributions of six fishes of greatest conservation need in streams in midwestern USA

Abstract Many fish species of greatest conservation need (SGCN) in Iowa and Minnesota, USA, have been in decline for decades. A key reason for the decline is the alteration and degradation of naturally flowing streams owing to land use changes resulting from agricultural practices. Populations of several fishes have been adversely affected by widespread stream channelization that has resulted in more homogeneous stream habitats throughout Iowa and Minnesota. The goal of this study was to determine the abiotic and fish assemblage characteristics associated with the presence of these rare fishes. Electrofishing and seining were used to sample fish assemblages and 43 abiotic characteristics were measured at 111 sites in the North Raccoon and Boone River basins in central Iowa and the Rock River and Beaver Creek basins in north‐west Iowa and south‐west Minnesota during 2016 and 2017. Six SGCN, including the federally endangered Topeka shiner (Notropis topeka), were included in statistical modelling to determine habitat and fish assemblage characteristics associated with their presence. Species‐specific nonmetric multidimensional scaling ordinations indicated that abiotic characteristics and fish assemblages often differed between sites where SGCN were present and absent. Random forest and logistic regression models suggested that the presence of four of six SGCN were positively associated with species richness, whereas all other 10 important abiotic and fish assemblage variables were unique to only one or two of the six SGCN. Topeka shiners were present at 36% of sites and were positively associated with orangespotted sunfish (Lepomis humilis) catch per unit effort while being negatively associated with canopy cover and fantail darter (Etheostoma flabellare) catch per unit effort.

Coal‐mining intensity influences species and trait distributions of stream fishes in two Central Appalachian watersheds

AbstractDocumenting responses of biotic assemblages to coal‐mining impacts is crucial to informing regulatory and reclamation actions. However, attributing biotic patterns to specific stressors is difficult given the dearth of preimpact studies and prevalence of confounding factors. Analysing species distributions and abundances, especially stratified by species traits, provides insights into how assemblage composition shifts occur. We evaluated stream habitats and fish assemblages along a mining intensity gradient in 83 headwater (2nd‐ and 3rd‐order) streams of the upper Clinch and Powell river basins in Virginia. Our multivariate gradient (MINE.PC1) was based on percentages of watershed area covered by surface mine, underground mine and valley fill to represent spatial variance in mining intensity. MINE.PC1 was positively correlated with conductivity and percentage of substrate as cobble. Forty fish‐assemblage metrics were analysed via boosted regression trees to assess assemblage responses to mining intensity, while accounting for environmental variation and spatial structure among sites. Conductivity and MINE.PC1 were strongly negatively related to occurrences of Fantail Darter (Etheostoma flabellare) and sculpin (Cottus) spp. Several taxonomic, trophic and reproductive metrics of assemblage composition responded strongly to mining intensity or its instream correlates. For example, coal mining favoured omnivore‐herbivores, but inhibited invertivores, simple lithophils and nonsimple nonlithophils. We revealed distinct negative and positive responses to mining‐related stressors, which suggest changes to macroinvertebrate prey availability and/or contaminant loads contribute to fish extirpations in coalfield streams. Future assessments of mining impacts on fish assemblages could be more instructive by including characterisations of physicochemical stressors and regionally calibrated biotic metrics with demonstrated sensitivity to mining.

Impacts on Metabolism and Gill Physiology of Darter Species (Etheostoma spp.) That Are Attributed to Wastewater Effluent in the Grand River

The effluent from municipal wastewater treatment plants is a major point source of contamination in Canadian waterways. The improvement of effluent quality to reduce contaminants, such as pharmaceuticals and personal care products, before being released into the environment is necessary to reduce the impacts on organisms that live in the river downstream. Here, we aimed to characterize the metabolic and gill physiological responses of rainbow (Etheostoma caeruleum), fantail (Etheostoma flabellare), and greenside (Etheostoma blennioides) darters to the effluent in the Grand River from the recently upgraded Waterloo municipal wastewater treatment plant. The routine metabolism of darters was not affected by effluent exposure, but some species had increased maximum metabolic rates, leading to an increased aerobic scope. The rainbow darter aerobic scope increased by 2.2 times and the fantail darter aerobic scope increased by 2.7 times compared to the reference site. Gill samples from effluent-exposed rainbow darters and greenside darters showed evidence of more pathologies and variations in morphology. These results suggest that darters can metabolically adjust to effluent-contaminated water and may also be adapting to the urban and agricultural inputs. The modification and damage to the gills provide a useful water quality indicator but does not necessarily reflect how well acclimated the species is to the environment due to a lack of evidence of poor fish health.

Use of Environmental DNA to Determine Fantail Darter (Etheostoma flabellare) Density in a Laboratory Setting: Effects of Biomass and Filtration Method

Estimating fish abundance/biomass holds great importance for freshwater ecology and fisheries management, but current techniques can be expensive, time-consuming, and potentially harmful to target organisms. Environmental DNA (eDNA) has proven an effective and efficient technique for presence/absence detection of freshwater vertebrates. Additionally, recent studies report correlations between target organism density/biomass and eDNA levels, although widespread application of this technique is limited by the number of studies examining this relationship in various species and settings. Additionally, filter clogging is a commonly encountered issue in eDNA studies in environments with significant sediment and/or phytoplankton algae. Frequently, a sample must be split into multiple aliquots and filtered separately in order to process the entire sample. The present study examines both the relationship between biomass and eDNA and the effects of single versus multiple filter sampling on eDNA concentrations of fantail darters (Etheostoma flabellare) in a laboratory setting. Tank tests were performed in quadruplicate at four environmentally relevant fantail biomass levels. eDNA samples were collected and processed in parallel (one as a whole through a single filter and one in parts through multiple filters). Species-specific primers and a probe were developed for E. flabellare from cytochrome b sequences obtained from locally collected specimens, and real-time quantitative PCR was used to analyze eDNA levels at each biomass. Significant correlations were observed with increasing biomass for both methods, although this relationship was stronger for samples processed by the multiple filter method. These data should be useful in eDNA studies in which turbidity necessitates the use of multiple filters per sample as well as in the use of eDNA to estimate darter populations.

Gut content biomass of stream fishes: associations with streamflow velocity, population density, and prey abundance at two spatial scales

Although food consumption rate has been identified as an important biological variable informing growth rates and population dynamics in fisheries management, equivalent measures receive little attention for native stream fishes. This research investigates whether spatial variation in fish gut fullness can be explained by streamflow velocity, population density, or prey abundance. We tested hypotheses associated with outcomes of habitat-specific energetic demands, exploitation competition, and resource-driven habitat use. Gut content biomass (GCB) of insectivorous fish species was compared at reach and at landscape scales in the Meramec River basin (Missouri, USA). Explanatory variables were selected using ridge regression with cross-validation. GCB of widely distributed species was correlated with body size, streamflow velocity, conspecific fish density, and prey abundance. At the reach scale, GCB was positively correlated with streamflow velocity in three species, supporting a prediction of an optimal foraging model. Negative relationships between GCB and density of Luxilus zonatus may be due to exploitation competition, while positive relationships between GCB and density of Etheostoma flabellare likely result from resource-driven habitat use. We found few relationships between GCB and explanatory variables at the landscape scale, suggesting that unmeasured biological and habitat variables are more important determining gut fullness at broad spatial scales.

Does Infection by the Monogenoidean Gill ParasiteAethycteron mooreiAffect Reproductive Ecology of the DarterEtheostoma flabellarein Mill Creek, Tennessee?

An increasing body of research shows the ability of parasites to alter the reproductive condition of their hosts, and the hosts' capacity to shift resources allocated to reproduction in response to parasitism. Here we compare host reproductive condition to gill parasite infection load in Fantail Darters (Etheostoma flabellare) of Mill Creek, Tennessee, USA, over the course of a year. We sought to determine whether host reproductive season or condition correlated with parasite load, whether parasite load differed between host sexes, and whether parasite load correlated with clutch size in females. We sampled the host population bimonthly and measured host physical and reproductive characteristics and gill parasite load. Infection levels significantly decreased when host reproductive activity ceased. Parasite load did not correlate strongly with body size in either sex. Male hosts were significantly more heavily infected than female hosts. No negative relationship was found between reproductive condition an...

Diel diet of fantail darter in a tributary to Lake Ontario, New York, USA

ABSTRACTThe foraging behavior of benthic fishes in streams is seldom examined but is vital to the health of the aquatic community. We examined the feeding ecology of the fantail darter (Etheostoma flaballere) in Trout Brook, a tributary of the Salmon River in central New York, USA. Of the six time periods examined, fantail darters fed most intensely from 1600–2000 h, with ephemeropterans the major prey consumed during all time periods except for 2000 where chironomid larvae were consumed the most. Fantail darter diet composition was similar across all time periods except during the night which appeared to be uniquely different. According to the prey selection analysis, fantail darters appear to prefer dipterans and ephemeropterans but also demonstrated an opportunistic behavior feeding on what was available in the brook.

Branched chain fatty acid content of edible portions of northeastern U.S. freshwater fish

IntroductionBranched chain fatty acids (BCFA) are major components of skin/membranes across various mammals and bacterial genera. BCFA are bioactive and alter gut microbiota. Intake of BCFA, mainly from dairy/beef was estimated at 500 mg per day in US. Our goal was to investigate BCFA levels in common freshwater fish species.MethodsWe captured over 20 fish species from several lakes and streams in New York and Pennsylvania. We dissected larger fish and sampled muscle tissue from dorsal and caudal fins as well as the belly and the skin. Smaller fish were entirely grinded before processing. All samples were extracted, saponified and methylated. BCFA profiles were analyzed using gas chromatography mass spectrometry.ResultsBCFA content varied across species and ranged from 0.6–2.7%, w/w of total fatty acids in fish muscle samples, with an overall mean of 1.2%. Some low trophic level fishes, such as killifish, rainbow smelt, and juvenile pumpkinseed, had over 2% BCFA while some common game fish species white perch, yellow perch, smallmouth bass, and walleye had about 1% BCFA, w/w or less of total fatty acids. A few low trophic level fishes such as fantail darter in the same perch family as yellow perch and walleye had low BCFA levels, suggesting influences related to phylogenetic structure. Skin contained between 1.2–3.2% BCFA, w/w of total fatty acids. Across all species sampled, skin samples had higher BCFA levels compared to muscle samples. The overall fatty acid profile, including BCFA was similar across muscles from different parts of a fish. The major BCFA in fish are iso‐15:0, anteiso‐15:0, iso‐16:0, iso‐17:0 and anteiso‐17:0. Trace amounts of iso‐13:0, anteiso‐13:0, iso‐14:0, iso‐18:0, anteiso‐19:0 and iso‐20:0 were also detected.ConclusionMany low‐trophic‐level fishes had BCFA levels comparable with dairy products and their skin samples showed higher BCFA content than muscle.Support or Funding InformationNIH R01 AT007003

Biological responses to contaminants in darters (Etheostoma spp.) collected from rural and urban regions of the Grand River, ON, Canada.

Urban and agricultural activities may introduce chemical stressors, including contaminants of emerging concern (CECs) and current use pesticides (CUPs) into riverine systems. The objective of this study was to determine if fish collected from various sites in the Grand River, ON, Canada show biomarkers of exposure to these classes of contaminants, and if the biomarker patterns vary in fish collected from urbanized and agricultural sites. Female rainbow darters (Etheostoma caeruleum) and female fantail darters (Etheostoma flabellare) were collected from the Grand River in June, 2014 for biomarker analysis from two urbanized sites and three agricultural sites. Over the same period of time, Polar Organic Chemical Integrative Samplers (POCIS) were deployed for 2weeks at each site to monitor for the presence of CUPs and CECs. Data on the liver somatic index for darters indicate site-specific differences in this condition factor (p<0.05). Significant differences in the levels of thiobarbituric acid reactive substances (TBARS) in gill tissue (p<0.05) of darters collected from the various sites indicate site-specific differences in oxidative stress. The activities of ethoxyresorufin-O-deethylase (EROD) in the liver tissue of rainbow darters were significantly different between sites (p<0.05), indicating differences in exposure to chemicals that induce or inhibit CYP450 1A metabolic activity. Finally, acetylcholinesterase (AChE) activity in brain tissue was significantly different between rainbow darters collected from rural and urban sites (p<0.05). These data showing different impacts from chemical inputs related to land uses in the watershed may be useful in developing mitigation strategies to reduce impacts on fish and other aquatic organisms in receiving environments.

Body shape variation in two species of darters (Etheostoma, Percidae) and its relation to the environment

AbstractEnvironmental variation can shape phenotypic variation in organisms, but most evidence for trait differentiation comes from analyses of dichotomous habitat types that differ in only one or few key environmental factors. In reality, environmental variation is often more subtle, gradual and multifarious. Here, we investigated geographic variation in body shape of two darter species (Etheostoma spectabileandEtheostoma flabellare; Percidae) that occur along river gradients. This study addressed three specific questions: Is there intraspecific geographic variation in the two species across different sites in the Ozark Highlands of Oklahoma (USA)? Is phenotypic variation across sites correlated with abiotic environmental conditions? Do the two species share site‐specific (i.e. convergent) phenotypic variation in areas where they occur together? Our results indicated significant body shape variation in both species. Population differences in body shape were particularly correlated with variation in substrate composition. The combined analysis of both species indicated a small but significant effect of convergence on body shape wherever they are sympatric; shared variation, however, was not related to any environmental variables included in the analysis. While it remains unclear whether phenotypic variation in these species is due to heritable differentiation or environmentally induced plasticity, our results indicate that even subtle and gradual environmental variation can induce substantial variation in phenotypes on a relatively small spatial scale.

Seasonal colour and antipredator behaviour in Etheostoma (Percidae)

This study examined how colour varies across season and sex in the fantail darter Etheostoma flabellare and the banded darter Etheostoma zonale. Etheostoma flabellare has male-only parental care and exhibited slight sexual dimorphism in overall colour, with no discernible effect of season on colour; whereas E. zonale does not have parental care and exhibited substantial sexual dimorphism in colour, but only in the breeding season. Additionally, antipredator behaviour of E. zonale was compared between males that were fully coloured during the breeding season and males that were partially coloured at that time, but the effects of colour and season were not consistent across males.

Population Demographics and Life History of the Round Hickorynut (Obovaria subrotunda) in the Duck River, Tennessee

Abstract Population characteristics and life history aspects of healthy mussel populations are poorly understood. The reproductive cycle, age and growth, and population structure of Obovaria subrotunda were examined at four sites in the middle Duck River, Tennessee. Obovaria subrotunda was confirmed to be a bradytictic species, spawning in the late summer and holding glochidia in the gills for 11 mo until the following summer. Fecundity was positively related to mussel length (R2 = 0.75) and ranged from 7122 to 76,584 glochidia. Fourteen species of fish found in the Duck River, in the families Percidae, Cyprinidae, and Cottidae, were infested with glochidia in the laboratory to examine potential hosts. Juveniles transformed on Etheostoma blennioides (greenside darter), E. obama (spangled darter), E. flabellare (fantail darter), and Cottus carolinae (banded sculpin). Analyses of shell thin-sections indicated that males grew faster and obtained a larger size than females. Individuals live to at least 14 y...

The fitness consequences of plastic responses to adult sex ratio in a paternal care fish

Plastic behavioural strategies may help individuals maximize reproductive success in varying environments, but it cannot be assumed a priori that behavioural responses to environmental changes are adaptive. To quantify the fitness consequences of plastic behavioural strategies in a paternal care fish, we observed the intrasexually competitive and intersexually solicitous behaviours of male fantail darters, Etheostoma flabellare, under varying adult sex ratios (ASR) for six observational periods over the course of two full mating seasons. At the end of each observational period, eggs present in each male's nest were counted. Behavioural and egg count data were used to construct linear and generalized linear mixed models predicting male reproductive success by two proxies: presence and number of eggs in the nest. Lower adult sex ratios (the ratio of males to females) and greater male length positively predicted egg presence. Greater intrasexual aggression increased a male's chances of having eggs in high ASR groups. Intrasexual aggression and solicitation of females positively predicted final egg count regardless of ASR. Our results support the hypothesis that some behavioural responses to changing adult sex ratio are adaptive, and that other traits, such as larger male size and high mate solicitation rates, may increase reproductive success regardless of ASR.

Habitat associations of fish assemblages in the Cache River, Illinois

Fish and habitat were sampled by state agencies at 48 stations throughout the Cache River watershed, Illinois between 1992 and 2009. Two distinct fish assemblages were identified, one primarily found in the lower mainstem Cache River and a second found throughout tributaries and the upper mainstem Cache River. Using a canonical correspondence analysis, the distribution of fish species was largely explained by substrate, land use, drainage area and local habitat features. Creek chub, central stoneroller, fringed darter and fantail darter are species found to be positively associated with gravel substrate and forest. In contrast, black buffalo, gizzard shad, smallmouth buffalo, freshwater drum and bigmouth buffalo were positively associated with drainage area, silt, channel width and row crops. Cobble appears to be rare habitat associated with fringed darter, freckled madtom and fantail darter. Results suggest that substrate, land use and local habitat features influence fish assemblages within the Cache River watershed. This information contributes to both understanding aquatic community structure in a highly altered yet diverse watershed as well as management activities within the Cache River watershed.

Habitat Use and Separation among Congeneric Darter Species

AbstractFive darter species (Greenside Darter Etheostoma blennioides, Rainbow Darter E. caeruleum, Fantail Darter E. flabellare, Johnny Darter E. nigrum, and Orangethroat Darter E. spectabile) were collected from seven streams and rivers in two Indiana watersheds to determine patterns of microhabitat selection with respect to depth, water velocity (flow), and substrate size. Heterogeneous habitats create a variety of niche dimensions, promoting the coexistence of congeneric species. Greenside and Rainbow darters were most commonly found among intermediate substrate sizes (cobble + boulder) and in locations with higher velocities and deeper water. Fantail and Orangethroat darters associated with intermediate to large substrate sizes (cobble + bedrock) were found in shallower water with lower velocities. Fantail Darters were only observed in the Whitewater River watershed. In contrast, Johnny Darters were observed only within the White River watershed among small substrate sizes (silt + sand), moderate velocities, and deeper water. Based on nonmetric multidimensional scaling and multinomial logistic regression, substrate size was the most important variable in characterizing microhabitat selection. Ultimately, habitats produced patterns of segregation and coexistence among these five darters in Indiana streams. Although ecological patterns of microhabitat use are additionally influenced by competition, morphology, and life history traits, heterogeneous habitat features within ecosystems appear to be structuring fish assemblages.

Interactions between invasive round gobies (Neogobius melanostomus) and fantail darters (Etheostoma flabellare) in a tributary of the St. Lawrence River, New York, USA

The initial, rapid expansion of the invasive round goby (Neogobius melanostomus) throughout the Great Lakes drainage was largely confined to lentic systems. We recently observed round gobies ascending two tributaries of the St. Lawrence River. The expansion of gobies into small lotic environments may place ecologically similar species at risk. Fantail darter (Etheostoma flabellare) is one of the several benthic species of the New York Great Lakes drainages that are threatened by round goby invasion. We examined the habitat use and diet composition of fantail darters and round gobies in Mullet Creek, a third-order tributary of the St. Lawrence River, NY, USA. The objectives of this study were to determine the degree of habitat and diet overlap between fantail darters and round gobies in a tributary of the St. Lawrence River. Gobies and darters co-occurred at 22% of capture sites. Of the four habitat variables examined (cover, depth, substrate and velocity), only depth use was significantly different with gobies using deeper habitats than darters. Among the two species and size classes sampled (large vs. small), large darters had the most restricted habitat use requirements. There was variation in round goby and darter diet composition, but only moderate diet overlap occurred between fantail darters and round gobies (Cλ = 0.43). Conditions in Mullet Creek were appropriate for the evaluation of possible spatial and dietary competition between round goby and native darters. Early detection and management of round goby invasions is critical to maintaining ecological integrity of lotic ecosystems in the St. Lawrence Valley.

Mate choice copying in two species of darters (Percidae: Etheostoma)

Mate choice copying is a form of social learning that is defined as the increased likelihood of an individual choosing a particular mate after observing another individual choosing that mate. Mate choice copying has been demonstrated in a range of taxonomic groups, but not usually for both sexes. Mate choice copying experiments were performed here using two congeneric sympatric darters, Etheostoma flabellare and E. zonale. In E. flabellare, males guard a nest site under a rock and care for developing eggs. In E. zonale, eggs are attached to filamentous green algae and neither sex provides parental care. Our results provide the first evidence that mate choice copying occurs in darters. Previously it was hypothesised that copying might be more common in species and sexes that provide parental care, the reasoning being that the costs of choosing poorly may be higher. However, mate choice copying was found in both sexes of E. zonale (no parental care) and in male but not female E. flabellare (male only parental care). Thus, the only group that did not mate choice copy was the one whose mate would be providing care, and even E. flabellare females copy the mate choice of other females by some definitions. The relationship, if any, between which sex provides parental care and whether copying occurs remains unclear, and the number of species for which such data are available is limited.