University of Wisconsin - Stevens Point
  • Stevens Point, United States
Recent publications
Understanding patterns of genetic structure and adaptive variation in natural populations is crucial for informing conservation and management. Past genetic research using 11 microsatellite loci identified six genetic stocks of lake whitefish (Coregonus clupeaformis) within Lake Michigan, USA. However, ambiguity in genetic stock assignments suggested those neutral microsatellite markers did not provide adequate power for delineating lake whitefish stocks in this system, prompting calls for a genomics approach to investigate stock structure. Here, we generated a dense genomic dataset to characterize population structure and investigate patterns of neutral and adaptive genetic diversity among lake whitefish populations in Lake Michigan. Using Rapture sequencing, we genotyped 829 individuals collected from 17 baseline populations at 197,588 SNP markers after quality filtering. Although the overall pattern of genetic structure was similar to the previous microsatellite study, our genomic data provided several novel insights. Our results indicated a large genetic break between the northwestern and eastern sides of Lake Michigan, and we found a much greater level of population structure on the eastern side compared to the northwestern side. Collectively, we observed five genomic islands of adaptive divergence on five different chromosomes. Each island displayed a different pattern of population structure, suggesting that combinations of genotypes at these adaptive regions are facilitating local adaptation to spatially heterogenous selection pressures. Additionally, we identified a large linkage disequilibrium block of ~8.5 Mb on chromosome 20 that is suggestive of a putative inversion but with a low frequency of the minor haplotype. Our study provides a comprehensive assessment of population structure and adaptive variation that can help inform management of Lake Michigan’s lake whitefish fishery and highlights the utility of incorporating adaptive loci into fisheries management.
Divergent life histories by sex are common within species of birds; thus, the ability to accurately determine sex is essential in many studies of avian ecology and can possibly lead to more effective conservation strategies. However, sex determination can be difficult in species not displaying dimorphic plumage, including most raptors, and size dimorphism has limited use during observations but is promising for determining sex of raptors in hand. The Broad-winged Hawk (Buteo platypterus), known for its long-distance migrations between North and South America, has yet to be examined for morphometric variation across its wide range. We analyzed body mass, wing chord, and tail length data for 119 adult Broad-winged Hawks captured in eastern North America during the breeding seasons from 1974 to 2020. We found that adult female Broad-winged Hawks were larger than adult males overall. Hawks from Wisconsin were larger than hawks from Pennsylvania and Maryland, and hawks from Ontario were larger than those from other populations, suggesting geographic variation in size. Using linear discriminant analysis, we showed that it was possible to determine sex of adults with 99% accuracy in Wisconsin populations using only body mass as a predictor, and 100% accuracy in Pennsylvania and Maryland populations using body mass, wing chord, and tail length as predictors. Morphometric measurements combined with discriminant function analysis proved useful in discerning sex of breeding-season Broad-winged Hawks, and results of this study can guide researchers working in similar regions. We encourage researchers to collect body measurements for this species and other monomorphic raptors to further inform sex determination.
Harvest of wild organisms is an important component of human culture, economy, and recreation, but can also put species at risk of extinction. Decisions that guide successful management actions therefore rely on the ability of researchers to link changes in demographic processes to the anthropogenic actions or environmental changes that underlie variation in demographic parameters. Ecologists often use population models or maximum sustained yield curves to estimate the impacts of harvest on wildlife and fish populations. Applications of these models usually focus exclusively on the impact of harvest and often fail to consider adequately other potential, often collinear, mechanistic drivers of the observed relationships between harvest and demographic rates. In this study, we used an integrated population model and long‐term data (1973‐2016) to examine the relationships among hunting and natural mortality, the number of hunters, habitat conditions, and population size of blue‐winged teal (Spatula discors), an abundant North American dabbling duck with a relatively fast‐paced life history strategy. Over the last two and a half decades of the study, teal abundance tripled, hunting mortality probability increased slightly (<), and natural mortality probability increased substantially (>) at greater population densities. We demonstrate strong density‐dependent effects on natural mortality and fecundity as population density increased, indicative of compensatory harvest mortality and compensatory natality. Critically, an analysis that only assessed the relationship between survival and hunting mortality would spuriously indicate depensatory mortality due to multicollinearity between abundance, natural mortality, and hunting mortality. Our findings demonstrate that models that only consider the direct effect of hunting on survival or natural mortality can fail to accurately assess the mechanistic impact of hunting on population dynamics due to multicollinearity among demographic drivers. This multicollinearity limits inference and may have strong impacts on applied management actions globally.
Acorns are a vital resource for many wildlife species and are required for oak (Quercus spp.) regeneration. Many different methods can be used to estimate acorn production and generate a hard mast index (HMI), however, the ability to compare data collected with different visual survey methods is limited. We conducted five visual acorn production survey methods on 70 oak trees (Quercus spp.) in northern Wisconsin from 1 August to 15 September 2020 to generate equations that convert indices of acorn production into a standardized index based on a 30-second count. We also used historical acorn production data from West Virginia (2000–2020) and North Carolina (2006–2019) for the standardization procedure. Indices from all visual survey methods were highly correlated to the 30-second count estimates, with HMI methods by Ryan et al., 2004, Greenberg et al., 2007 having the strongest relationships (r = 0.99) with the 30-second count. The conversion equations from this study will provide managers a means of comparing data across visual survey methods and will expand the ability for future research in relation to acorn production.
River otters (Lontra canadensis) are widespread in the United States and are managed for sustainable fur harvest throughout much of their range in the United States. Despite their widespread distribution, river otters can be difficult to monitor due to their cryptic nature and the inaccessible habitats they often occupy. Additionally, there has been little research conducted to quantify winter habitat selection patterns of river otters. We used 4 years of aerial survey data conducted during the winter to quantify habitat selection patterns of river otters in Wisconsin, USA, and to determine factors associated with survey efficacy. We used a mixed‐effects logistic regression framework to evaluate habitat and anthropogenic factors at 2 spatial scales. We found that river otters were positively associated with the amount of forested and wetland habitat within a 1 km buffer around sampling locations, but that no factors we measured were influential at a local (100 m) scale. River otters were more likely to be detected when ice cover was only partial as opposed to when ice coverage was complete or when it was completely absent. Our results suggested that river otter habitat selection in Wisconsin is not strongly affected by anthropogenic influences but instead by broad‐scale habitat configuration. Furthermore, our results suggested that aerial survey approaches for river otters can be optimized by conducting surveys during periods when ice coverage is sufficient to allow for clear tracking substrate without being prevalent enough to limit movements into and out of corresponding aquatic habitats. We used survey data collected during aerial monitoring efforts to assess winter habitat selection by river otters. We found that otter sign was more likely to be found in areas with high levels of forested and wetland land cover. We also found that otter sign was most likely to be detected with partial ice coverage on waterways.
Alternate Uses Test (AUT) is one of the most popular divergent thinking tasks and commonly used to measure creativity. Researchers using AUT often pick an everyday object and instruct participants to think of possible uses for it. Yet, the word frequency of the selected objects may impact the outcomes. The present study investigates the variation in the fluency scores from AUT in terms of word frequency values of the selected everyday object. We expected a positive relationship between the word frequency metrics and the fluency scores when other potential factors are controlled such as time-on-task, explicit instructions, the form of task administration and a number of various psycholinguistic characteristics. The mean effect (average fluency score) is 9.08, 95% [7.54, 10.61] from 114 effects from 31 studies. There was a significant interaction effect of Time-on-Task and Word Frequency (β = -.01, t (3.05) = -3.51, p = .038). These findings indicate that word frequency is correlated with fluency scores under strict time conditions, and this effect seems to disappear with lenient time conditions. The results are discussed based on the recommended assessment practices in the literature.
Trees make our cities and urban areas more livable. Trees provide many benefits, known as ecosystem services, to residents. Cities often make management plans and care for their trees to increase the benefits provided by their urban forests. These plans often include goals to increase tree cover. This study assessed tree cover in 300 Florida (U.S.A.) cities. Each city’s urban tree canopy coverage (a percentage of how much of a city is covered by the leafy tops of trees) was analyzed. The goal was to assess the effects of hurricanes, past land cover, and local laws on total tree cover. The study found that hurricanes can decrease tree canopy coverage. It also found that the type of land cover present before a city was built can predict present canopy coverage. Results also found that some local laws can protect or enhance urban tree canopy, even in the face of city development and natural disasters.
Interspecific interactions among walleye Sander vitreus, lake whitefish Coregonus clupeaformis, and yellow perch Perca flavescens in Green Bay could influence the population status of each species, but potential trophic interactions are poorly understood. Our objectives were to determine if diet assemblages for each species and diet overlap among species varied spatially and temporally within Green Bay. Adult walleye (≥381 mm total length (TL); N = 981), lake whitefish (≥432 mm TL; N = 1507), and yellow perch (≥150 mm TL; N = 1174) were collected during May-October of 2018 and 2019 from multiple locations in southern and northern Green Bay. Diet assemblages of each species varied between northern and southern Green Bay, but walleye diets were more temporally variable (among months within zones and between years) than diets of lake whitefish or yellow perch. Lake whitefish represented a seasonally important prey item for walleye in southern Green Bay, composing 10 % and 41 % of walleye diets by weight in May and June, respectively. Yellow perch generally composed <15 % of walleye diets by weight but were consumed at a broader spatiotemporal scale than lake whitefish. Diet overlap between walleye and both lake whitefish and yellow perch was generally weak or moderate, whereas diet overlap between whitefish and perch was generally strong. Our assessment of adult trophic interactions suggests that changes in the population status of one species could influence fisheries for all three, and we identify additional research questions to address potential population-level effects of these trophic interactions.
Fish behavior after passage or transfer around dams is a critical component in determining whether the goals of these efforts are achieved, but these behaviors are often poorly understood. An elevator was constructed in the lowermost hydroelectric dam on the Menominee River, Wisconsin–Michigan; it is the first elevator specifically designed to capture Lake Sturgeon Acipenser fulvescens for upstream transfer above two dams, providing access to high‐quality spawning and early life habitat. Our objectives were to determine whether (1) Lake Sturgeon transferred upstream remained upstream for at least one spawning opportunity; (2) spawning opportunity, time to reach the next dam upstream, and residency in different segments of the river were related to sex, capture method (elevator versus electrofishing), and season of transfer; and (3) the probability of fish transitioning back downstream of the two dams varied among months. We evaluated posttransfer behaviors of 139 Lake Sturgeon that were captured in the elevator or by electrofishing, implanted with acoustic transmitters, transferred upstream (in spring or fall) from fall 2014 to spring 2017, and monitored until fall 2018 using 20–23 stationary acoustic receivers deployed throughout the river. Most Lake Sturgeon (91%) remained upstream for at least one spawning opportunity. The probability of remaining for one spawning opportunity was not related to sex, fish capture method, or season of transfer. Residency times within the two impoundments and time to reach the next dam upstream varied among individual fish. A multistate model indicated that monthly survival after upstream transfer was high and that Lake Sturgeon typically remained above both dams in late fall to early spring, with most downstream movements occurring in April and May. Our results indicate that Lake Sturgeon transferred upstream have the potential to contribute offspring that may help to bolster the Lake Sturgeon population in Lake Michigan, but additional research may help in determining whether these contributions occur. Impact Statement Lake Sturgeon that were transferred upstream of two dams remained upstream of the dams for at least one spawning opportunity, representing the first step in determining whether transfers can be used to increase Lake Sturgeon abundance in the Great Lakes and beyond.
We report the case of a 35-week gestation infant girl born by emergent cesarean section for fetal distress in a woman with recent coronavirus disease 2019 (COVID-19). Tests for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) using polymerase chain reaction (PCR) on the infant at 24 and 48 hours of life were negative. However, at 72 hours of life, the infant’s respiratory status worsened, and a repeat SARS-CoV-2 PCR was positive. The infant developed leukopenia, thrombocytopenia, and progressive respiratory failure, and died on the ninth day of life. Pathologic examination of the placenta revealed findings consistent with COVID-19 placentitis, and SARS-CoV-2 RNA staining was positive, suggesting intrauterine transmission of the infection.
Lake Herring (also known as Cisco) Coregonus artedi, a cold‐water salmonid found in the Great Lakes is of interest to multiple agencies for restoration and conservation purposes due to their important ecological role. Further information on rearing and restocking of Cisco are needed, especially understanding the biological culture needs of eggs, larvae, and fingerling Cisco. To address this gap in the literature and provide needed fish culture information, we performed three early preliminary studies in 2010 with Lake Herring: fertilization (wet versus dry fertilization), egg survival (pre‐water hardening versus post‐water hardening iodine treatment), and fry development with three different larval feed treatments commercially available at this time. Dry fertilization methodology (68%) had a significantly better eye‐up percentages when compared to wet fertilization (34%). Additionally, our testing revealed higher survival rates when iodophor treatment was used on fertilized eggs post‐water hardening (54%) in comparison to before water hardening (43%). Although mean survival rates across the three diet treatments were not statistically significant, larval Lake Herring fed artemia replacement diets outperformed the other diets with Inve‐Proton diet ranking best. These early preliminary studies substantially increased understanding of the optimum culturing parameters of Lake Herring in preparation for widespread production of this important species and provide propagation recommendations for conservation stocking programs.
The purpose of this cross-sectional study was to determine the differences in narrative macrostructure abilities of children in different age groups using a progress monitoring tool based in discourse theory. A majority of existing research regarding narrative developmental patterns has been based in schema theory. The Monitoring Indicators of Scholarly Language (MISL) rubric is based in discourse theory and was designed to characterize aspects of narrative proficiency in school-age children. The data for this project consisted of 687 narratives elicited using the Aliens subtest from The Test of Narrative Language—Second Edition (TNL-2). There were 1,597 participants who ranged in age from 4; 0 to 15; 0 (year; month). An ordinary least squares regression where age predicted total macrostructure score, followed by a series of post hoc ordinal logistic regressions (OLR) where age predicted each individual MISL rubric element was used. Results of both the simple regression on total macrostructure score and the series of ordinal regression analyses for each macrostructure element indicated that age was a significant predictor of the scores children received. Collectively, these results suggest that the MISL is a developmentally valid measure of narrative production abilities. Developmental milestones based on discourse theory are reported to be substantially later than has been reported for schema theory. The differences are highlighted and the implications for progress monitoring for narrative development are discussed.
The effect of Parasite‐S® (an aqueous formaldehyde solution) on the nitrification processes of biofilters was evaluated in two recirculating aquaculture systems (RASs). Rearing tanks in the warmwater RAS contained yellow perch (Perca flavescens) and grass carp (Ctenopharyngodon idella) with an initial weight of 166.8 kg and a mean density of 39.5 kg/m3. Rearing tanks in the coldwater RAS contained rainbow trout (Oncorhynchus mykiss) and lake trout (Salvelinus namaycush) with an initial weight of 1377.8 kg at a system density of 41.9 kg/m3. Parasite‐S® was administered to the entire system on four consecutive days in both trials to achieve a nominal concentration of 14.8 mg/L formaldehyde (40 mg/L formalin) at the biofilter. Removal efficiencies for total ammonia nitrogen (TAN) and nitrite nitrogen were measured as indicators of biofilter nitrification processes. The active ingredient in Parasite‐S®, formaldehyde, was measured until it was below the method detection limit of 0.8 mg/L. TAN volumetric removal rate was significantly decreased in both systems after formaldehyde addition and remained below pre‐exposure efficiency in the coldwater RAS. Nitrite nitrogen volumetric removal rate was not significantly different, but the slope and intercepts were less after formaldehyde addition indicating an effect on the nitrifying bacteria. Although removal rates were decreased, no mortality occurred after four consecutive formaldehyde indefinite bath exposures in either system.
Background and Aims Intervessel pit membranes (PMs) are important cell wall structures in the vessel system that may impact a plant’s water transport and its susceptibility to vascular diseases. Functional roles of intervessel PMs largely depend on their structure and polysaccharide composition, which are the targets of this study. Methods With grapevine used as a model plant, this study applied an immunogold-scanning electron microscopy technique to simultaneously analyze intervessel PM structures and major pectic and hemicellulosic polysaccharides that compose intervessel PMs at high resolution. Key Results Intervessel PMs in functional xylem showed significant structural variation with about 90 % of them being structurally intact with smooth or relatively smooth surfaces and the remaining 10 % with progressively degraded structures. The results also elucidated details of the removal process of cell wall materials from intervessel PM surface toward its depth during its natural degradation. Four groups of pectic and hemicellulosic polysaccharides were immunolocalized in intervessel PM and differed in their spatial distribution and abundance. Weakly methyl-esterified homogalacturonans (WMe-HGs, detected by JIM5) was abundant in the surface layer, heavily methyl-esterified homogalacturonans (HMe-HGs, detected by JIM7) and xylans detected by CCRC-M140 were mostly found in deeper layers, and fucosylated xyloglucans (F-XyGs, detected by CCRC-M1) were more uniformly distributed at different depths of the intervessel PM. Conclusions Intervessel PMs displayed diverse structural variations in grapevine. They contained certain major groups of pectic and hemicellulosic polysaccharides with different spatial distributions and abundance. This information is crucial to reveal the polysaccharide profiling of the primary cell wall and to understand intervessel PM’s roles in the regulation of water transport as well as in a plant’s susceptibility to vascular diseases.
The study was carried out in order to determine the effect of coating formulations on printing quality. For this purpose, five different coating formulations were created in which kaolin and precipitated calcium carbonate pigments (PCC) were mixed in different proportions. Coating formulations were applied in two layers on a base cardboard. Calendering of the coated base cartons was carried out using a laboratory calender. The prints were made on the calendered cardboards using mineral oil-based, vegetable (soybean) oil-based, and UV inks in a laboratory type offset printing machine. As a result of the study, it was determined that the coating of the base cardboard surface affects the optical and physical properties of the cardboard, the surface properties change according to the amount of pigment used in the formulations, and this change affects the printing quality. In the study, the best printing results in terms of printing quality were obtained with the use of UV ink. Mineral oil-based and vegetable (soybean) oil-based ink were compared in terms of printing quality, and since the values obtained are close to each other, it can be said that vegetable oil-based inks can be preferred instead of mineral oil-based ink, and more environmentally friendly sustainable productions can be realized. It has always provided better results in terms of surface smoothness and printability in coated formulations where the kaolin ratio is increased.
The rapid evaporation of 1:1 solutions of diethynylpyridines and N-halosuccinimides, that react together to form haloalkynes, led to the isolation of unreacted 1:1 cocrystals of the two components. The 1:1 cocrystal formed between 2,6-diethynylpyridine and N-iodosuccinimide (C4H4INO2·C9H5N) contains an N-iodosuccinimide-pyridine I...N halogen bond and two terminal alkyne-succinimide carbonyl C-H...O hydrogen bonds. The three-dimensional extended structure features interwoven double-stranded supramolecular polymers that are interconnected through halogen bonds. The cocrystal formed between 3,5-diethynylpyridine and N-iodosuccinimide (C4H4INO2·C9H5N) also features an I...N halogen bond and two C-H...O hydrogen bonds. However, the components form essentially planar double-stranded one-dimensional zigzag supramolecular polymers. The cocrystal formed between 3,5-diethynylpyridine and N-bromosuccinimide (C4H4BrNO2·C9H5N) is isomorphous to the cocrystal formed between 3,5-diethynylpyridine and N-iodosuccinimide, with a Br...N halogen bond instead of an I...N halogen bond.
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1,122 members
Erik Wild
  • Department of Biology
Tomi Heimonen
  • Department of Computing and New Media Technologies (CNMT)
Ronald E. Masters
  • Department of Forestry
Wesley Larson
  • Department of Fisheries and Water Resources
Brian Sloss
  • College of Natural Resources
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Stevens Point, United States