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Objective: The potential influence (i.e., impact rate) of catch‐and‐release fisheries on wild steelhead Oncorhynchus mykiss is poorly understood and is a function of the abundance of wild fish, how many fish are encountered by anglers (i.e., encounter rate), and the mortality of fish that are caught and released. In Idaho, estimates of wild steelhead encounter rates have been derived using the number of wild and hatchery steelhead passing Lower Granite Dam, the number of hatchery steelhead harvested, and the number of hatchery steelhead caught and released. The method includes assumptions that hatchery and wild steelhead have equal encounter rates and catch‐and‐release mortality is 5% for wild steelhead. Here, we investigated wild and hatchery steelhead encounter rates by anglers, estimated catch‐and‐release mortality, and concatenated both aspects to examine how existing recreational steelhead fisheries influence wild steelhead mortality. Methods: We sampled, tagged, and released 1,251 spawn‐year 2020 (SY2020) and 1,956 spawn‐year 2021 (SY2021) adult steelhead at Lower Granite Dam with T‐bar anchor tags and passive integrated transponder (PIT) tags to estimate steelhead encounter rates and catch‐and‐release mortality. Differences in survival of caught steelhead and those not reported as caught were evaluated using detections at various locations (e.g., PIT arrays, weirs). Result: Estimated encounter rates were 43.7% (95% credible interval; 28.2%, 100.0%) for wild fish and 46.7% (29.6%, 100.0%) for adipose‐clipped fish in SY2020. In SY2021, encounter rates were 47.2% (32.4%, 100.0%) for wild fish and 52.3% (37.1%, 100.0%) for adipose‐clipped fish. Based on detections of caught fish and those not reported as caught, catch‐and‐release mortality of wild steelhead was estimated to be 1.6% (0.0%, 5.2%). Wild steelhead impact rates were 0.7% (0.0%, 2.7%) in SY2020 and 0.7% (0.0%, 2.8%) in SY2021. Conclusion: Estimated rates of impact on wild steelhead were consistent and low across years despite major differences in the structure of the fisheries. Our results suggest assuming that encounter rates are equal between hatchery and wild steelhead, and that steelhead catch‐and‐release mortality is 5%, will likely lead to a conservative estimate of the wild steelhead impact occurring from catch‐and‐release fisheries. Impact statementWith wild steelhead numbers declining in many parts of North America, a dilemma between providing angling opportunity and wild steelhead conservation can develop. We show that encounter rate plays a larger role than mortality regarding catch‐and‐release angling on overall impact rates. Our method provides a direct, reliable estimate of encounter rates across multiple scales. [ABSTRACT FROM AUTHOR]

Objective: Anecdotal evidence suggests that the term "pollster" has, in recent years, become stigmatized in the United States. We explore this and a subsequent question as to whether negative perceptions of pollsters affect people's perceived trustworthiness of survey findings. Methods: Survey experiments were administered to national probability‐based samples after the 2016 and 2020 elections. Results: In each study, pollsters obtained significantly more negative ratings when compared to "survey researchers" and "public opinion researchers," suggesting that the general public views pollsters, who are more likely to be viewed as partisan, as being less honest/ethical. In line with social identity theory, interaction models revealed that those rating pollster critic Donald Trump most favorably had the most negative ratings of pollsters and public opinion researchers, compared to survey researchers. Yet, the vignette experiment showed that negative perceptions of pollsters did not affect the perceived trustworthiness of survey result reports. Conclusions: We conclude that while there appears to be a stigmatization of pollsters, those negative perceptions do not translate into less trust in the findings of public opinion. [ABSTRACT FROM AUTHOR]

Objective: With response rates of large‐scale surveys having decreased significantly over the years and rebounds seeming unlikely, many studies now examine how response rates vary with methodological design and incentives. This investigation delves into how individual‐level factors shape survey participation. Specifically, we examine the influence of individuals' democratic engagement and their trust in institutions on intent to participate in surveys, both directly and indirectly through their perceptions of surveys. Methods: We collected survey data from a probability sample of adults (N = 1343) in Mannheim, Germany, from November 2019 to March 2020. Structural equation models were estimated to test the hypothesized relationships. Results: The analyses support most, but not all, hypothesized relationships. Democratic engagement bolstered intent to participate, directly as well as indirectly through perceptions of surveys. Institutional trust, on the other hand, only influenced the outcome measure indirectly. Perceptions of surveys had a strong bearing overall effect on intent to participate. Conclusion: The study's results suggest that the response rates and larger issues related to the perceived legitimacy of public opinion and survey research might be intertwined with orientations related to people's civic and political life. The article discusses potential ways survey researchers can counteract distrust in surveys. [ABSTRACT FROM AUTHOR]

Migrations are a critical component of the life histories of many highly mobile animals. Potamodromous migrations that occur within large lakes are poorly understood for most species. This lack of understanding hampers restoration efforts and adaptive management because the movement of species and underlying patterns and mechanisms help scientists identify important habitats and quantify species' roles in the ecosystem. This study quantified the spatiotemporal movements and migratory patterns of Lake Trout Salvelinus namaycush, an iteroparous, potamodromous predator, in eastern Lake Ontario. The lake is highly managed and supports a diverse fish community of native and nonnative species. The movements of 41 Lake Trout were quantified over 2.4 years (December 2016 to April 2019) across a large array of 196 acoustic receivers in eastern Lake Ontario. An analysis of individual movements revealed a potential annual convergence occurring in the fall at a location other than the spawning grounds, followed by a synchronized migration to spawning areas. Consistent with divergent migrations, return migration was asynchronous among individuals but consistent in timing interannually, stretching over a longer period than did prespawning movements and across multiple routes. The data suggest the existence of three groups (i.e., contingents) of Lake Trout with distinct migratory behaviors. This study provides important information on the migratory patterns and routes and a potential staging area for a potamodromous top predator population in a large lake. This information can help managers understand the potential success and implications of employing different rehabilitation strategies, such as diversifying populations of Lake Trout through selective strain stocking in large deep lakes to aid reestablishment across habitats. In addition, our results have the potential to improve community dynamics modeling, understanding of nutrient cycling, and overall ecosystem function of large lakes. [ABSTRACT FROM AUTHOR]

Point sources such as wastewater treatment plants, terrestrial agriculture, and aquaculture may release antibiotic residues, antibiotic resistant bacteria, and antibiotic resistance genes (ARGs) into aquatic ecosystems. However, there is a lack of quantitative studies attributing environmental ARG abundance to specific sources. The goal of this study was to evaluate the role of freshwater trout farms in the release and dissemination of ARGs into the environment. Sediment samples upstream and downstream from five rainbow trout farms were collected over time in southern Chile. A microfluidic quantitative polymerase chain reaction approach was used to quantify an ARG array covering different mechanisms of resistance, and data were analyzed using principal component analysis (PCA) and linear mixed regression models. Surveys were also conducted to obtain information about management practices, including antibiotic use, at the farms. Florfenicol and oxytetracycline were used at these farms, although at different rates. A total of 93 samples were analyzed. In the PCA, strB, sul1, sul2, qacG, tet(A), tet(B), tet(C), tet(W), and floR grouped together. A statistically significant increase in abundance of qacG, strB, sul1, and several tet genes was found downstream from the farms compared with upstream sites, and retention ponds had the highest ARG abundance at each site. Antibiotic resistance gene levels returned to baseline at an average distance of 132.7 m downstream from the farms. Although results from this study indicate an influence of trout farms on the presence of ARGs in the immediate environment, the extent of their contribution to ARG dissemination is unknown and deserves further investigation. Core Ideas: Point sources contribute to antimicrobial resistance (AMR) in the environment.Antibiotic resistance genes (ARG) were quantified in river sediment samples.Freshwater trout farms in southern Chile increased ARG abundance in the watershed.The extent of the contribution of the trout farms on ARG dissemination is uncertain.Epidemiological methods are needed to attribute environmental AMR to specific point sources. [ABSTRACT FROM AUTHOR]

Abstract: Telemetry studies often assume a lack of adverse effects caused by tag attachment and presence in various species and size‐classes, which may lead to inaccurate conclusions about fish behavior in field studies. Studies that examine the effects of tagging are typically performed on salmonids and adult fishes rather than on the small fishes that are increasingly becoming the focus of telemetry studies. The objectives of this study were to assess the effects of intracoelomic acoustic tagging on growth, condition, survival, and tag retention in subadult hatchery Bloaters Coregonus hoyi (a focal species for restoration efforts in the Laurentian Great Lakes) and to determine the maximum tag burden below which tag effects are reduced. Fish were either tagged with one of three dummy acoustic transmitters (Vemco V6: n = 50; V7: n = 50; V9: n = 50) or were followed as controls (n = 50; anesthesia, PIT‐tagging, and handling only) or sham individuals (n = 49; anesthesia, surgery, suturing, and PIT‐tagging but no acoustic tag implanted). Tags represented 1.3–9.0% of body mass. All fish received a PIT tag for individual identification throughout the 6‐month monitoring period (November 2014–May 2015). Survival exceeded 90% in all treatment groups, and the tag retention rate was 100%. All surviving fish appeared healthy and in excellent condition at the conclusion of the experiment. The results of this study suggest that acoustic transmitters with a tag mass : body mass ratio of 9% or less can be successfully implanted intracoelomically into subadult Bloaters—small, laterally compressed pelagic fish—with no adverse effects. [ABSTRACT FROM AUTHOR]

Objectives: To determine the prevalence of rheumatic heart disease (RHD) in school-aged children and young people in Timor-Leste.Design: Prospective cross-sectional survey. Echocardiography was performed by Australian cardiologists to determine the presence of RHD. Demographic data were also collected. Patients in whom RHD was detected were entered into a register to allow monitoring of adherence to secondary prophylaxis; the first dose of benzathine penicillin G (BPG) was administered on the day of screening.Setting: Schools in urban (Dili) and rural (Ermera) Timor-Leste.Participants: School students aged 5-20 years.Outcome Measures: Definite and borderline RHD, as defined by World Heart Federation echocardiographic criteria.Results: 1365 participants were screened; their median age was 11 years (IQR, 9-14 years), and 53% were girls. The estimated prevalence of definite RHD was 18.3 cases per 1000 population (95% CI, 12.3-27.0 per 1000), and of definite or borderline RHD 35.2 per 1000 (95% CI, 26.5-46.4 per 1000). Definite (adjusted odds ratio [aOR], 3.5; 95% CI, 1.3-9.4) and definite or borderline RHD (aOR, 2.7; 95% CI, 1.4-5.2) were more prevalent among girls than boys. Eleven children (0.8%) had congenital heart disease. Of the 25 children in whom definite RHD was identified, 21 (84%) received education and a first dose of BPG on the day of screening; all 25 have since received education about primary care for RHD and have commenced penicillin prophylaxis.Conclusions: The rates of RHD in Timor-Leste are among the highest in the world, and prevalence is higher among girls than boys. Community engagement is essential for ensuring follow-up and the effective delivery of secondary prophylaxis. [ABSTRACT FROM AUTHOR]

Abstract: The aim of the present study was to validate the Korean American Parental Depression Literacy Scale (Parental D‐Lit Scale), which was modified from Griffith's Depression Literacy Scale based on expert reviews, individual and focus group interviews, and a cross‐sectional, self‐administered survey. Survey participants included Korean American mothers (n = 107, 74.8%) and fathers (n = 36, 25.2%) of adolescent children. We examined reliability and validity using exploratory factor analysis (EFA), confirmatory factor analysis (CFA), and correlational and comparison analyses. The scale showed moderate reliability and validity (α = 0.72) and content validity (scale‐level content validity index = 0.875). EFA resulted in a three‐factor model, and CFA showed a close fit to the data (root mean square error of approximation = 0.056). Reliability indices indicated that total scale scores were more useful for examining depression literacy than subscale scores. Criterion validity was supported by statistically‐significant correlations in the expected direction between depression literacy and other theoretically‐related constructs, including attitudes towards mental health‐care services (+), depression stigma (−), recognition of depression (+), and acculturation (+). The Parental D‐Lit Scale scores showed statistically‐significant mean differences between parents who identified depression in a vignette (mean = 18.3, standard deviation (SD) = 2.9) and those who did not (mean = 16.8, SD = 4.0), indicating the discriminant validity of the scale. The Parental D‐Lit Scale shows promise for use by psychiatric/mental health nurses in assessing the effectiveness of educational and clinical interventions. Additional research should employ larger samples in various regions of the USA. [ABSTRACT FROM AUTHOR]

Management agencies need to understand the factors that influence fishing license purchases. While traits such as gender can influence the decisions of recreational fishers, a gap remains in understanding the influence of catch-related fishing quality on these decisions. We evaluated the use of fish biomass density as a proxy for catch-related fishing quality along with non-catch-related factors (population density, gender, and ethnicity) to explain variation in 2014 resident fishing license rates across 510 origins in Ontario. License rates were higher in areas with lower population density (i.e., rural areas), in areas with higher fish biomass density, and among populations with stronger representation by ethnic majorities. From simulated scenarios, we predicted that resident license sales could increase between 14% and 25% if fish biomass density increased by 30% and 54% in northeastern and southern Ontario, respectively. However, license sales could decrease between 5% and 10% with a 30% redistribution of rural residents to a major urban area. The relationship between license rates and non-catch-related factors confirms the role of urbanization on recreational fishing participation, while catch-related factors provide support for a functional response by fishers to fish. Received April 28, 2016; accepted October 3, 2016Published online January 3, 2017 [ABSTRACT FROM PUBLISHER]

Understanding reproduction and mating systems is important for managers tasked with conserving vulnerable species. Genetic tools allow biologists to investigate reproduction and mating systems with high resolution and are particularly useful for species that are otherwise difficult to study in their natural environments. We conducted parentage analyses using 19 nuclear DNA microsatellite loci to assess the influence of population density, genetic diversity, and ancestry on reproduction, and to examine the mating system of pygmy rabbits ( Brachylagus idahoensis) bred in large naturalized enclosures for the reintroduction and recovery of the endangered distinct population in central Washington, USA. Reproductive output for females and males decreased as population density and individual homozygosity increased. We identified an interaction indicating that male reproductive output decreased as genetic diversity declined at high population densities, but there was no effect at low densities. Males with high amounts (>50%) of Washington ancestry had higher reproductive output than the other ancestry groups, while reproductive output was decreased for males with high northern Utah/Wyoming ancestry and females with high Oregon/Nevada ancestry. Females and males bred with an average of 3.8 and 3.6 mates per year, respectively, and we found no evidence of positive or negative assortative mating with regards to ancestry. Multiple paternity was confirmed in 81% of litters, and we report the first documented cases of juvenile breeding by pygmy rabbits. This study demonstrates how variation in population density, genetic diversity, and ancestry impact fitness for an endangered species being bred for conservation. Our results advance understanding of basic life history characteristics for a cryptic species that is difficult to study in the wild and provide lessons for managing populations of vulnerable species in captive and free-ranging populations. [ABSTRACT FROM AUTHOR]

Nonindigenous bigheaded carps (Bighead CarpHypophthalmichthys nobilisand Silver CarpH. molitrix; hereafter, “Asian carps” [AC]) threaten to invade and disrupt food webs and fisheries in the Laurentian Great Lakes through their high consumption of plankton. To quantify the potential effects of AC on the food web in Lake Erie, we developed an Ecopath with Ecosim (EwE) food web model and simulated four AC diet composition scenarios (high, low, and no detritus and low detritus with WalleyeSander vitreusand Yellow PerchPerca flavescenslarvae) and two nutrient load scenarios (the 1999 baseline load and 2× the baseline [HP]). We quantified the uncertainty of the potential AC effects by coupling the EwE model with estimates of parameter uncertainty in AC production, consumption, and predator diets obtained using structured expert judgment. Our model projected mean ± SD AC equilibrium biomass ranging from 52 ± 34 to 104 ± 75 kg/ha under the different scenarios. Relative to baseline simulations without AC, AC invasion under all detrital diet scenarios decreased the biomass of most fish and zooplankton groups. The effects of AC in the HP scenario were similar to those in the detrital diet scenarios except that the biomasses of most Walleye and Yellow Perch groups were greater under HP because these fishes were buffered from competition with AC by increased productivity at lower trophic levels. Asian carp predation on Walleye and Yellow Perch larvae caused biomass declines among all Walleye and Yellow Perch groups. Large food web impacts of AC occurred in only 2% of the simulations, where AC biomass exceeded 200 kg/ha, resulting in biomass declines of zooplankton and planktivorous fish near the levels observed in the Illinois River. Our findings suggest that AC would affect Lake Erie's food web by competing with other planktivorous fishes and by providing additional prey for piscivores. Our methods provide a novel approach for including uncertainty into forecasts of invasive species' impacts on aquatic food webs. Received December 6, 2014; accepted July 15, 2015 [ABSTRACT FROM PUBLISHER]

Woodpeckers and other primary cavity excavators (PCEs) are important worldwide for excavating cavities in trees, and a large number of studies have examined their nesting preferences. However, quantitative measures of wood hardness have been omitted from most studies, and ecologists have focused on the effects of external tree- and habitat-level features on nesting. Moreover, information is lacking on the role of wood hardness in limiting nesting opportunities for this important guild. Here, we used an information theoretic approach to examine the role of wood hardness in multi-scale nest site selection and in limiting nesting opportunities for six species of North American PCEs. We found that interior wood hardness at nests (n = 259) differed from that at random sites, and all six species of PCE had nests with significantly softer interior wood than random trees (F1, 517 = 106.15, P < 0.0001). Accordingly, interior wood hardness was the most influential factor in our models of nest site selection at both spatial scales that we examined: in the selection of trees within territories and in the selection of nest locations on trees. Moreover, regardless of hypothesized excavation abilities, all the species in our study appeared constrained by interior wood hardness, and only 4-14% of random sites were actually suitable for nesting. Our findings suggest that past studies that did not measure wood hardness counted many sites as available to PCEs when they were actually unsuitable, potentially biasing results. Moreover, by not accounting for nest site limitations in PCEs, managers may overestimate the amount of suitable habitat. We therefore urge ecologists to incorporate quantitative measures of wood hardness into PCE nest site selection studies, and to consider the limitations faced by avian cavity excavators in forest management decisions. [ABSTRACT FROM AUTHOR]

Population-based estimates of substance use patterns have been regularly reported now for several decades. Concerns with the quality of the survey methodologies employed to produce those estimates date back almost as far. Those concerns have led to a considerable body of research specifically focused on understanding the nature and consequences of survey-based errors in substance use epidemiology. This paper reviews and summarizes that empirical research by organizing it within a total survey error model framework that considers multiple types of representation and measurement errors. Gaps in our knowledge of error sources in substance use surveys and areas needing future research are also identified. [ABSTRACT FROM AUTHOR]

Survey research is a common tool for assessing public opinions, perceptions, attitudes, and behaviors for analyses in many social science disciplines. Yet there is little knowledge regarding how specific elements of survey research methodology are applied in practice in public administration. This article examines five mainstream public administration journals over an eight-year period regarding current methodological practice, organized around the total survey error framework. The findings show that survey research in the field of public administration features mainly small-scale studies, heavy reliance on a single data collection mode, questionable sample selection procedures, and suspect sample frame quality. Survey data largely are analyzed without careful consideration of assumptions or potential sources of error. An informed evaluation of the quality of survey data is made more difficult by the fact that many journal articles do not detail data collection procedures. This study concludes with suggestions for improving the quality and reporting of survey research in the field. [ABSTRACT FROM AUTHOR]

While predation is widely accepted as a major cause of mortality for fish larvae, its extent is largely unknown because few studies have been able to identify larvae in the stomach contents of predatory fish. Rapid digestion rates probably explain why fish larvae are rarely found in stomach contents, yet quantification of digestion rates of fish larvae is generally lacking, especially in freshwater systems. Using a series of laboratory experiments, we quantified the effects of temperature and larval fish (prey) size on digestion rate. We also evaluated whether species type (both predator and prey) influences digestion rate and described the morphological breakdown of fish larvae during digestion. Bluegills and yellow perch were force-fed the larvae of guppies spp., rainbow trout , and yellow perch at a range of temperatures (7-22°C), and digestion rates were measured using prey mass before and after digestion (i.e., proportional loss of prey mass after ingestion). As expected, digestion rates increased with water temperature and decreased with prey body mass but were unaffected by species of predator. A confounding effect of prey type (fresh versus frozen) prevented a thorough evaluation of prey species, although yellow perch and rainbow trout (both previously flash-frozen) were digested at similar rates. The complete breakdown of larvae in predator stomachs and the loss of morphological characters needed to identify larvae occurred rapidly, confirming the challenges of evaluating predation mortality based on stomach contents of field-collected predators. Ultimately, our findings can be used to help researchers quantify the likelihood of detecting larval fish in the stomachs of field-caught predators when using conventional stomach content analyses. [ABSTRACT FROM AUTHOR]