62 research outputs found

    Channel Catfish Diets Include Substantial Vegetation in a Missouri River Reservoir

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    Channel catfish (Ictalurus punctatus) are native to Lake Sharpe, a Missouri River mainstem reservoir, and are common in angler catches. Channel catfish growth has declined since the formation of the reservoir in 1963. Mean lengths at time of capture for channel catfish ages 9, 10, II, and 12 have decreased by 69, 55, 115, and 21S mm, respectively, since impoundment. The objective of this study was to document monthly food habits of channel catfish throughout the growing season (May-August) in Lake Sharpe to assess potential effects of diet on growth. Although channel catfish consumed both macro invertebrates and fishes as expected, they also consumed large quantities of submergent aquatic vegetation. Consumed vegetation contributed 3S-73% of the diet by weight over 2 channel catfish length groups «2S0 mm and ~2S0 mm total length) during the 4 months sampled. Consumption of substantial amounts of vegetation should be considered a suboptimal diet for channel catfish growth. Consequently, diets of channel catfish in Lake Sharpe could be a factor contributing to the observed slow growth of older catfish in this population

    Depth and Littoral Habitat Association of Age-0 Yellow Perch in Two South Dakota Glacial Lakes

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    Yellow perch (Perca flavescens) are a recreationally important species and represent a key ecological component of glacial lake littoral fish assemblages (Stone 1996, Blackwell et al. 1999). Research has shown a generalized pattern of juvenile (age-0) yellow perch spatial distribution wherein larvae hatch in near-shore areas, migrate to limnetic areas where they remain for approximately 40 d, and then return to demersal behaviors and within near-shore littoral habitats (Noble 1975, Whiteside et al. 1985). However, anomalous distribution and habitat use by age-0 yellow perch has been observed in South Dakota glacial lakes (Fisher and Willis 1997) and the spatial distribution and habitat association of post-larval (\u3e25 mm) age-0 perch is largely unverified in northern Great Plains glacial lakes. Herein, we report the depth distribution and near-shore (0–2 m depth) habitat association of post-larval, age-0 yellow perch (hereafter referred to as age-0 yellow perch) in two northeastern South Dakota glacial lakes

    You Can’t Teach Wildlife and Fisheries Online, Can You? A Comparison of Student Learning and Satisfaction in Two Online and Face-to-Face Courses

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    Criticisms of online science courses are rooted in the lack to of hands-on learning experiences only available in the face-to-face (f2f) environment. Very few studies have compared student learning outcomes (e.g., assignment, exam, and final grades; level of learning achieved) and student satisfaction between online and f2f courses in the science curriculum, and none of these studies has been done for applied natural resources courses. We are currently conducting a quasi-experiment to compare student learning outcomes and satisfaction for online and f2f versions of two introductory wildlife and fisheries sciences course at South Dakota State University (WL 220: Introduction to Wildlife and Fisheries and WL 230: Wildlife and Fisheries Techniques). To date, we have documented demographic differences between online and face-to-face students in the two courses. Online students tend to be older, have full-time employment, be more experienced in the online environment, and identify themselves more as visual learners than f2f students. Some differences in learning outcomes have been associated with time spent in learning activities within each environment. In the online WL 230 course, the average time spent per week on course tasks was positively associated with overall course grade and individual scores received on assignments related to applying, analyzing, and evaluating information. Time spent outside of class was negatively related to overall course grade in the f2f environment, but class attendance was positively related to course grade and scores on individual assignments that emphasized applying, analyzing, and evaluating information. Insights gleaned from this study may be used to improve and expand online applied natural resources courses. Expansion of these courses may be vital as applied natural resources curricula have been lost nationwide, but these types of knowledge are still very much in demand

    Channel Catfish Diets Include Substantial Vegetation in a Missouri River Reservoir

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    Channel catfish (Ictalurus punctatus) are native to Lake Sharpe, a Missouri River mainstem reservoir, and are common in angler catches. Channel catfish growth has declined since the formation of the reservoir in 1963. Mean lengths at time of capture for channel catfish ages 9, 10, II, and 12 have decreased by 69, 55, 115, and 21S mm, respectively, since impoundment. The objective of this study was to document monthly food habits of channel catfish throughout the growing season (May-August) in Lake Sharpe to assess potential effects of diet on growth. Although channel catfish consumed both macro invertebrates and fishes as expected, they also consumed large quantities of submergent aquatic vegetation. Consumed vegetation contributed 3S-73% of the diet by weight over 2 channel catfish length groups «2S0 mm and ~2S0 mm total length) during the 4 months sampled. Consumption of substantial amounts of vegetation should be considered a suboptimal diet for channel catfish growth. Consequently, diets of channel catfish in Lake Sharpe could be a factor contributing to the observed slow growth of older catfish in this population

    Population and Diet Assessment of White Bass in Lake Sharpe, South Dakota

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    White bass (Morone chrysops) have been introduced into all 4 South Dakota Missouri River reservoirs and compose a substantial proportion of the annual recreational harvest. To date, limited studies have examined white bass population dynamics and food habits in South Dakota Missouri River reservoirs. Our objective was to examine population dynamics and food habits of white bass in Lake Sharpe, a South Dakota mainstem Missouri River reservoir. White bass consistently consumed invertebrates during May but switched to a more piscivorous diet later in the growing season; most of the fish consumed were gizzard shad (Dorosoma cepedianum). Information from this study adds to the body of knowledge of white bass population dynamics and their role in fish communities that is necessary for successful management of those communities

    Depth and Littoral Habitat Association of Age-0 Yellow Perch in Two South Dakota Glacial Lakes

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    Yellow perch (Perca flavescens) are a recreationally important species and represent a key ecological component of glacial lake littoral fish assemblages (Stone 1996, Blackwell et al. 1999). Research has shown a generalized pattern of juvenile (age-0) yellow perch spatial distribution wherein larvae hatch in near-shore areas, migrate to limnetic areas where they remain for approximately 40 d, and then return to demersal behaviors and within near-shore littoral habitats (Noble 1975, Whiteside et al. 1985). However, anomalous distribution and habitat use by age-0 yellow perch has been observed in South Dakota glacial lakes (Fisher and Willis 1997) and the spatial distribution and habitat association of post-larval (\u3e25 mm) age-0 perch is largely unverified in northern Great Plains glacial lakes. Herein, we report the depth distribution and near-shore (0–2 m depth) habitat association of post-larval, age-0 yellow perch (hereafter referred to as age-0 yellow perch) in two northeastern South Dakota glacial lakes

    Synchrony in larval yellow perch abundance: the influence of the Moran Effect during early life history

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    : Recruitment may vary substantially in fish populations, which can drive not only adult population characteristics but also the dynamics of fishes dependent on the species of interest and recreational fisheries for these species. However, spatiotemporal trends in population fluctuations and potential drivers of recruitment variability are poorly understood. Therefore, we used a long-term (2000–2014) data set to estimate the extent of spatial synchrony in larval abundance and factors influencing variability in recruitment of yellow perch (Perca flavescens). Contrary to the prevailing paradigm that spatial synchrony in population fluctuations (i.e., recruitment) is typically absent or occurs at small spatial scales (\u3c50 km) for freshwater species, abundance of larval yellow perch was synchronous among spatially segregated systems across a geographic scale of at least 180 km. Additionally, variation in larval yellow perch density was influenced by spatially-correlated climatic and hydrological variables (indicative of the Moran Effect). Results ultimately broaden the scale at which factors were previously thought to influence recruitment of freshwater fishes and provide important insight to patterns and processes that structure yellow perch populations

    Sampling Glacial Lake Littoral Fish Assemblages with Four Gears

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    Littoral zone fish assemblages are important components of freshwater lakes. Monitoring of littoral fish assemblage structure is important because littoral fishes often comprise the majority of the entire fish assemblage, and fluctuations in the structure and abundance of the littoral fish assemblage can influence trophic interactions and fishery yields at the ecosystem level. Single-gear sampling designs, however, may only capture a subset of the fish assemblage, resulting in a skewed representation of fish assemblage structure. Use of multiple gears can be justified if they provide complementary fish assemblage information. Our objective was to compare glacial lake fish assemblage structure as represented by four gears and to assess whether the gears provide redundant or complementary fish assemblage information. Two northeastern South Dakota glacial lakes were sampled with a beach seine, benthic sled, drop net, and push trawl in August 2011. Results indicated that fish assemblage structure did not differ significantly among gears. However, fish assemblage descriptors (metrics of species richness, diversity, dominance, and evenness) and rates of species accumulation did differ among gears; in comparison with the drop net, the beach seine, benthic sled, and push trawl collected more individuals with qualitatively greater species richness and diversity at a faster rate. The beach seine collected the most individuals representing the greatest number of species with the least amount of sampling effort (i.e., fastest rate of species accumulation); thus, we recommend the use of beach seines for monitoring and assessment of littoral fish assemblages in glacial lakes

    Comparison of Four Types of Sampling Gears for Estimating Age-0 Yellow Perch Density

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    To aid biologists in obtaining reliable and efficient estimates of age-0 yellow perch (Perca flavescens) abundance, we compared operational effort and catch characteristics (i.e., density, length frequencies, and precision) of four gear types (beach seines, benthic sleds, drop nets, and push trawls) in littoral habitats in two South Dakota glacial lakes. Gear types were selected on the basis that the volume of water sampled could be determined and, thus, density (number/m3 ) of age-0 yellow perch could be computed for each. Age-0 yellow perch were collected on three occasions with each gear in both lakes in August 2011. Differences in gear operational effort (i.e., the time required for set-up, deployment, and fish sorting) and age-0 yellow perch density and length frequencies were compared among sampling gears. Mean operational effort ranged from 9 to 65 min, mean density from 0.07 to 4.1 age-0 yellow perch/m3 , coefficients of variation of mean age-0 perch density from 33 to 134, and number of samples required to estimate a 25% change in mean age-0 perch abundance from 22 to 305. Beach seines and drop nets may selectively sample larger age-0 yellow perch than benthic sleds and push trawls. We recommend use of beach seines or benthic sleds for sampling age-0 yellow perch in littoral habitats of glacial lakes. However, all sampling gears tested in this study have associated costs and benefits and one may be more suitable than another under different circumstances
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