Dams provide different services for human society, but they also significantly disrupt ecosystems by altering natural flow and temperature regimes. Here, we describe a novel, unappreciated threat posed by reservoirs to one of the world's most popular game fish, brown trout (Salmo trutta). We show that small river impoundments elevate downstream water temperature during summer, which increases the prevalence and abundance of Tetracapsuloides bryosalmonae parasite triggering proliferative kidney disease (PKD), an emerging disorder in salmonids across North America and Europe. Our study highlights the role of reservoirs in creating parasite and disease hotspots, while providing limited evidence that dams act as barriers to parasite spread. This makes downstream areas from reservoirs valuable sentinel sites for monitoring climate impacts on riverine ecosystems. Ultimately, the assessment of dams requires a more holistic approach, where the disease risks are included in the decision-making process balancing human needs with the health of aquatic ecosystems.

Black bass (Micropterus spp.) are the most important warmwater game fishes in the United States. They have high socioeconomic and recreational value and support an important aquaculture industry. Since 2008, fisheries managers have been reporting the observation of hyperpigmented melanistic lesions (HPMLs) on smallmouth bass (M. dolomieu) in different ecoregions of the United States. Similar HPMLs have been observed in largemouth bass (M. nigricans) since the 1980’s. Here, we report the association between novel adomaviruses and the hallmark blotchy clinical presentation of hyperpigmented lesions on the skin of smallmouth and largemouth black bass. The two adomaviruses are structurally and phylogenetically similar but share only 68.0% identity at aligned nucleotide sites and each has been found in only one host species to date. The manifestation of this skin disease appears to be seasonal (observed between the fall and spring) in both species, primarily affects adults and is of unknown health consequence. Although the significance of infection to fish health remains unclear, understanding the disease ecology of these viruses can inform biosecurity and the interjurisdictional movement of individuals. Moreover, as hyperpigmentation in other fish species is often idiopathic, our findings reframe perspectives for future investigations into this clinical presentation in other species.

Inland fisheries provide essential ecosystem services, yet they face growing threats from anthropogenic activities and climate change. To sustainably manage these fisheries under global change, understanding the main drivers of freshwaters fish populations is key. Since the late 1980s, the Québec government has conducted standardized gillnet surveys to monitor game fish species and their habitats. Here, we identified the main drivers influencing the abundance of walleye, brook trout, and lake trout. Through random forest models, we analyzed 662 lakes and 38 predictor variables, revealing that fish community composition shaped the abundance of the two salmonid species. The best model performance was for brook trout (R2=0.54), followed by lake trout (R2=0.46), and walleye (R2=0.44). Brook trout populations were larger in allopatric lakes, while lake trout abundances were smaller in association with large piscivores. On the other hand, climate was more important for walleye. The dominant explanatory variables varied across species, suggesting different ecological niches. Our findings deepen understanding of fish population drivers in Québec lakes, highlighting the need for management plans to consider fish community context.

ABSTRACT Objective Spotted Bass Micropterus punctulatus and Alabama Bass M. henshalli have been recognized as separate species for close to two decades, yet they continue to be managed as a single species under the same standard weight (Ws) equation and length categories despite known differences in body form and growth potential. The objective of this study was to develop and assess new Ws equations and length categories for proportional size distribution indices to better inform management decisions for each species. Methods Length and weight data for Alabama Bass were obtained from 32 populations across six states, totaling 41,341 individuals; data for Spotted Bass were obtained from 127 populations across 11 states, totaling 86,602 individuals. Using these data, three new Ws equations were created for both species with the regression line percentile, empirical percentile–linear (EmP-L), and empirical percentile–quadratic techniques. New standard length categories were derived from the current International Game Fish Association world record for Alabama Bass and from the mean of state records from 10 states for Spotted Bass. Results For Alabama Bass, all three techniques produced reasonable Ws equations that dramatically outperformed the old equation. For both species, the EmP-L and empirical percentile–quadratic equations displayed less length bias in relative weight estimates than the regression line percentile equation, but neither empirical percentile equation was notably superior. Therefore, we propose that the new Ws equations for both species should be the simpler EmP-L version following the suggestions of previous studies. With total length (TL) in millimeters and weight (WT) in grams, the Alabama Bass equation is log10(WT) = −5.6189 + 3.284·log10(TL) and the Spotted Bass equation is log10(WT) = −5.3467 + 3.197·log10(TL). The old standard length categories proposed for Spotted Bass should be retained for Alabama Bass; those values are 180, 280, 350, 430, and 510 mm TL, representing stock, quality, preferred, memorable, and trophy categories, respectively. For Spotted Bass, we propose the following standard length categories: 150, 230, 300, 350, and 440 mm TL, respectively. Conclusions These Ws equations and standard length categories better match the body form and growth potential of both species and will provide biologists with improved tools to monitor the condition and size structure of these important sport fishes.

Abstract Habitat loss and fragmentation has isolated many species into small geographic areas. This is especially true of stream fishes, where alteration of waterways has restricted many species to headwater tributaries, leading to low abundances and threatening loss of genetic diversity. In addition, hybridization and introgression with introduced game fishes can impact the distribution of genetic variation among native populations. To assess the effects of habitat extent and hybridization on genetic diversity in a stream dwelling fish, we conducted a study of Redband Trout ( Oncorhynchus mykiss gairdneri ) populations within the southernmost drainages of the Snake River basin. Introgression between Redband Trout and hatchery strains of coastal Rainbow Trout ( Oncorhynchus mykiss irideus ) was found in nearly half of the populations assessed, where high levels of admixture corresponded to increased heterozygosity. Independent of hybridization, the level of genetic diversity was found to be positively related to habitat extent, with populations occupying over 10 km of stream exhibiting higher heterozygosity than those in under 5 km of stream. While high levels of genetic diversity in nonhybridized populations may correspond to elevated adaptive potential, increased genetic diversity due to introgression represents a potential concern to fitness due to the effects of outbreeding depression.

Worldwide, freshwater systems contain more than 18,000 fish species1-3, which are critical to the functioning of these ecosystems4 and are vital cultural and economic resources to humans5-7; despite this value, fish biodiversity is at risk globally8,9. In the USA, leading threats to fish communities in rivers and streams include climate change and invasive fish introductions and game fish stocking by humans10-14. Here we harmonized US federal biomonitoring datasets with 389 species spanning 27 years (1993-2019) and 2,992 sites to analyse trends in fish biodiversity. In cold streams (past summer stream temperatures below 15.4 °C), fish abundance and richness declined by 53.4% and 32% over 27 years, respectively, and uniqueness increased. Periodic (large-bodied, late-maturing) fishes increased, and opportunists (small-bodied, short generation time, 'r-selected') decreased, possibly due to proliferation of native or introduced game fishes. In warm streams (stream temperatures greater than 23.8 °C), fish abundance and richness increased by 70.5% and 15.6% over 27 years, respectively, and communities homogenized. Small opportunistic fishes replaced large periodic fishes. Intermediate streams (stream temperatures 15.4-23.8 °C), representing the average stream, had minimal changes in fish biodiversity through time. Interactions between warming and introduced fish were associated with increased rates of degradation to local fish biodiversity. Given the magnitude of these changes in a relatively short time span, there is an urgent need to curb degradation of fish biodiversity caused by fish introductions and warming water temperatures.

ABSTRACT Objective Standard weight (Ws) and standard length categories have not been established for the Longear Sunfish Lepomis megalotis. Therefore, fisheries managers have been unable to evaluate condition and size structure of various populations across the species’ range. Our objectives were to develop and assess Ws equations using three different techniques and to propose standard length categories for Longear Sunfish. Methods Length and weight data were collected for Longear Sunfish from 17 states across the species’ native and introduced range. Data from 54,106 fish across 512 populations were used to develop Ws equations for Longear Sunfish by using the regression line percentile, linear empirical percentile, and quadratic empirical percentile techniques. Standard length categories for Longear Sunfish were developed using the length from the International Game Fish Association’s all-tackle world record. Results We propose the regression line percentile equations as log10W = 3.3127·log10L − 5.2861, where W is weight (g) and L is total length (mm) for metric units, and log10W = 3.3114·log10L − 3.2887, where W is weight (lb) and L is TL (inches) for English units. We also developed proportional size distribution length categories of 60, 100, 130, 170, and 210 mm TL, representing stock, quality, preferred, memorable, and trophy categories, respectively. Conclusions Our Ws equations and standard length categories will allow fisheries biologists to better understand and manage Longear Sunfish populations across their native and introduced range.

The implementation of the Blooket game Fishing Frenzy mode has been proven effective in Arabic vocabulary learning at the elementary level. The use of Blooket in learning creates an enjoyable atmosphere, making students actively engaged and preventing boredom. This study aims to analyze the application of Blooket in Arabic vocabulary learning at MIN 1 Kota Malang.The research method used is a quasi-experimental design with a pretest-posttest control group design. The study sample consists of 56 students divided into an experimental group using Blooket and a control group using conventional methods. The research instrument includes an Arabic vocabulary test, and the collected data was analyzed using SPSS 20. The results show a significant improvement in students' learning outcomes after implementing the Blooket game, as reflected in the comparison between pre-test and post-test scores, with an average N-Gain of 77.8. Additionally, hypothesis testing results indicate a significance value of 0.006, which is lower than 0.05, leading to the rejection of Ho and acceptance of Ha. Based on these findings, it can be concluded that the implementation of the Blooket game effectively enhances students' interest and learning outcomes in Arabic vocabulary.

Black bass (Micropterus spp.) are the most important warmwater game fishes in the United States. They have high socioeconomic and recreational value and support an important aquaculture industry. Since 2008, fisheries managers have been reporting the observation of hyperpigmented melanistic lesions (HPMLs) on smallmouth bass (M. dolomieu) in different ecoregions of the United States. Similar HPMLs have been observed in largemouth bass (M. nigricans) since the 1980’s. Here, we report a close association between novel adomaviruses and the hallmark blotchy clinical presentation of hyperpigmented lesions on the skin smallmouth and largemouth black bass and provide evidence that satisfies Rivers’ postulates. The two adomaviruses are structurally and phylogenetically similar but share only 68.0% identity at aligned nucleotide sites and each has been found in only one host species to date. The manifestation of this skin disease appears to be seasonal in both species, primarily affects adults and is of unknown health consequence. Although the significance of infection to fish health remains unclear, understanding the disease ecology of these can inform biosecurity and the interjurisdictional movement of individuals. Moreover, as hyperpigmentation in other fish species is often idiopathic, our findings reframe perspectives for future investigations into this clinical presentation in other species.

Historically, locally transmitted fishborne trematodiasis has not been a public health concern in the United States (US). However, the widespread introduction of the first intermediate host snail Melanoides tuberculata and 2 of the fishborne trematodes it transmits (Haplorchis pumilio and Centrocestus formosanus), along with their discovery at freshwater fishing localities throughout southern California, reveals a need to further evaluate the risk of local transmission of fishborne trematodiasis in the US. Here, we confirm that the trematode stages infectious to people (metacercariae) commonly infect and can be abundant in 7 commonly caught and eaten fish species at California fishing localities. Further, via an online social media search, we provide evidence that people throughout the US eat those same fish species in ways conducive to trematode transmission (namely, eating fish unfrozen and raw). These findings further indicate the plausibility for locally transmitted fishborne trematodiasis in the US.

ABSTRACT Fisheries management has historically focused conservation efforts on game or sport species. However, most species are nongame—those not traditionally captured for sport or harvest in countries where recreational fisheries predominate. Greater conservation of nongame species could help ensure that population declines do not go unnoticed. Unfortunately, fisheries managers already manage complex ecosystems with limited resources, and they frequently are directed to focus on game fishes. However, game fish populations can also be tightly coupled to nongame fishes, so nongame management can sometimes also benefit game species. We reviewed functional roles of freshwater nongame fishes and suggest categories that may be especially important for conservation. Of note, nongame fishes are more imperiled than game fishes and fill largely distinct functional roles. These roles include food-web impacts, ecosystem engineering, and mussel hosting. Management priorities could include nongame piscivores and species with high biomass, especially herbivores, nest builders, and imperiled mussel hosts. We provide practical options for including nongame fishes in current management, many of which require little additional funding. These include recognizing when sport fish funding and conservation can also benefit nongame species, whole-community sampling at some monitoring locations, collecting catch data for select species observed during game fish surveys, embracing environmental DNA sampling, and making presence–absence record keeping the default option.

• Walleye, brook trout and lake trout occurrence and abundance examined in 94 lakes. • Fish occurrence was predicted by zooplankton taxa with ∼73 % of correct predictions. • Of all three fish species, walleye abundance was the best predicted by zooplankton. • Cladoceran biomass emerged as the strongest zooplankton indicator of fish abundance. • Environment and fish community composition variables remained better predictors. Recreational inland fisheries play a vital role in the economy and culture of Canada. However, human activities and climate change are significant threats to lakes that sustain such fisheries, bolstering the need to maintain ecosystem quality while sustaining fisheries through approaches such as ecosystem-based management. Despite the importance of zooplankton communities for fish diet, very few freshwater management plans have integrated information from this lower trophic level. Here, we used a dataset including game fish abundance, crustacean zooplankton community composition and associated habitat variables in 94 north temperate lakes across the province of Quebec, Canada. Our study aimed to uncover whether zooplankton taxonomic and functional community properties were related to walleye, brook trout, and lake trout occurrence and abundance. Our analyses revealed that both taxonomic and functional zooplankton composition were significant predictors of focal fish species occurrence, albeit less so than environmental or fish community composition variables. When examining the importance of 30 different zooplankton community indices for target fish species abundance, structural equation modeling revealed that zooplankton was more important for walleye than for the two other fish species. Overall, this research improves our understanding of zooplankton-fish interactions and how these shape north temperate lake communities, with a perspective of improving fisheries conservation and management.

Culinary tourism has necessitated the development and use of local food as a gateway to a destination's cultural heritage. In culinary tourism, tourists travel to experience unique and authentic culinary traditions. The uniqueness is in the manner in which the cuisine is prepared, produced and presented. Destinations are using their local foods to bring out that uniqueness, luring tourists to visit them. However, in Zimbabwe the destination is seemingly less visible as an attraction on local food. Since time immemorial, tourist resort areas like Victoria Falls have been the main attraction for tourists visiting Zimbabwe. Besides the provision of local foods such as game meat, mushrooms, fish and local vegetables and a few food activities held, not much is known about the destination's culinary heritage. In fact, culinary tourism is still in its infancy in Zimbabwe. This study therefore used a quantitative research methodology to explore the culinary heritage of Zimbabwe. Data was collected from local and international tourists in Victoria Falls and Harare using a closed ended questionnaire. The quantitative data was analysed using SPSS version 23, Findings indicated that culinary tourism was not yet an attraction for tourists visiting Zimbabwe. The results showed that though most hotels and restaurants were providing indigenous cuisines, there was limited variety, the prices were not favourable, and the cuisines' authenticity was also questionable. Implications of these results was that a lot needs to be done to illuminate the uniqueness of Zimbabwe's culinary heritage.

Unplanned urbanization and economic development can deteriorate water quality (WQ) and alter its beneficial usage. Continuous monitoring of biotic and abiotic parameters describing the WQ is essential to track changes and classify water resources to protect public health. Various invest significant effort, money, and time in monitoring programs. Using data from those sources is challenging due to the large number of observations, and inconsistencies in sampling time, date, stations, and gaps. This study aims to design different water quality index (WQI) models to provide policymakers, stakeholders, and water managers with a more comprehensive assessment by converting complex datasets from over 10 years, processed with the statistical software R, into consistent data sets. These datasets are then transformed into small principal components. WQ datasets of lakes and reservoirs in the western USA were chosen as case studies. The strategy of data processing is explained, and the results organized as a descriptive summary of the 12,000 observations for 31 parameters are discussed. Outputs of principal component analysis (PCA) are used to create relative and absolute WQI models for water irrigation usage and protecting cold- and warm-water species of game fish. Weighted arithmetic water quality indices are applied, and the relation between different models is examined.

ABSTRACTThe growing popularity of digital catch logs may present a low‐cost opportunity to monitor climate change effects on the distribution and relative abundance of game fishes over large spatial scales. We analyzed data from a popular fishing app to identify spatiotemporal trends in freshwater game fish catches throughout the contiguous the United States during 2015–2021. Warm‐water species became more common than cool‐water species in many locations. Increases in relative abundance tended to occur in northern range boundaries or non‐native ranges, and declines tended to occur at southern range boundaries. Although catch log data can be biased and results may reflect alternative phenomena operating or interacting at similarly large spatial scales (e.g., cultural eutrophication, changes in game fish popularity), climate change remains a viable explanation. Future research should further explore app data as a potential tool for monitoring game fish responses to climate change and other stressors over longer time frames and at multiple spatial scales.

Brown Trout (Salmo trutta), a popular game fish in the Black Hills’ sport fishery, is poorly understood when it comes to seasonal movements in many Black Hills streams. We attempted to determine short and long-term movement patterns, seasonal movement changes (spawning and pre-winter), habitat preference and document mortality events across a 9-month period using radio telemetry. Twenty-five adult (227 - 421 mm) Brown Trout were surgically implanted with radio transmitters during the Summer of 2023. Movements throughout the study decreased throughout the period of sampling. Pre-spawning movements averaged 171 m in the short-term and 1,558 m over this phase. During the spawning period, movements decreased to 154 m short-term and 625 m long-term along with a further decrease post-spawn (20 m short-term, 310 m long-term). Habitat preferences during the pre-spawning (pools 23%, riffles 17%, runs 60%) and spawning season (pools 26%, riffles 12%, runs 63%) were different from those in the post-spawning season (pools 46%, riffles 5%, runs 49%), and three documented predation events occurred strictly during the post-spawning season. These findings give managers valuable insight towards seasonal movement patterns, habitat use and extent of predation on a wild Brown Trout fishery.

The scientific article reveals the issue of identifying and characterizing the circumstances to be established during the investigation of illegal employment in fish, game or other water extractive fishing. As a result of thorough research and analysis of publications by criminologists and proceduralists, it was found that at the current stage of development, the specified issue remains insufficiently researched. Distinguished positions of scientists who determine that the development of separate methods of investigation of criminal offenses should begin with the definition of the range of tasks and circumstances to be established. As a result of the analysis of forensic scientists and generally recognized circumstances to be established, it has been proven that the circumstances that need to be clarified in the course of detected illegal actions related to illegal water extractive fishing should include: the event of illegal water extractive fishing in terms of the presence of forensically significant signs of an offense under Art. 249 of the Criminal Code of Ukraine (time, place, circumstances of preparation, commission, concealment; tools, means and method of use; identity of the criminal, motives and purpose), as a priority, since a timely and objective assessment of the analyzed situation allows prompt and correct adoption of relevant organizational decisions regarding the initiation of a pre-trial investigation, which will positively affect the next stage; culpability in committing a criminal offense, form of guilt, motive and purpose of committing a criminal offense (the main thing is whether the signs of the committed act fall under the legal prohibitions of fishing; what exact requirements were violated when fishing was carried out); the type and amount of significant damage caused as a result of illegal fishing; the amount of material damage caused to the environment by an illegal act; identification of witnesses to the event, as well as circumstances that affect the severity of the committed criminal offense (presence of accomplices, group nature, mass fishing, etc.). Clarification of the circumstances highlighted in the scientific article contributes to the proper further organization of the investigation of illegal employment in fish, game or other water extractive fishing.

The article defines the concept of criminalistic characteristics of illegal employment in fish, game or other water extractive fishing and outlines its main structural elements. The opinions of the leading criminologists regarding the essence of the criminological characteristics are highlighted, and a proper concept was formed based on them. In the course of the study, it was determined that the forensic characterization of illegal employment in fish, game or other water extractive fishing should be understood as an organized collection of forensic information on significant typical features that distinguish the criminal offense provided for in Art. 249 of the Criminal Code of Ukraine from other criminal offenses and determine the system of operative and investigative measures and procedural actions aimed at his detection and the fulfillment of the tasks of criminal proceedings provided for in Art. 2 of the Criminal Procedure Code of Ukraine during the investigation. All elements of forensic characteristics are interdependent, the detection of internal connections allows, knowing one element of the criminal offense system, to gain knowledge about some other elements and ultimately to uncover a criminal offense. The content of the forensic characterization should include the features of the methods and traces of the relevant types of criminal offenses, the circumstances characterizing the participants in criminal illegal acts and their illegal connections, the objective side, time, place, conditions of committing criminal offenses, the object of the offense and relationships connection of the listed factors. That is why, the elemental-component structure of the criminalistic characterization of the criminalistic characterization of illegal employment in fish, game or other aquatic extractive industry, as a data system based on the practice of law enforcement agencies and forensic research, includes: 1) the subject of criminal encroachment; 2) the setting of the crime and the trail picture; 3) ways of committing; 4) information about persons who have committed a criminal offense (identity of the offender). The specified elements most accurately reveal the content of forensic characteristics in the process of developing a methodology for investigating illegal fishing, animal or other water extractive fishing.

Models are needed to predict changes in game fish abundances with respect to climatic factors undergoing change, but such models are often limited by data availability and the capacity of statistical methods to fit challenging ecological datasets. We use current methods in machine learning to describe the responses of 10 fish species to climatic factors across Québec. We assembled a new province-wide, synthetic dataset of fish catches spanning almost 50 years and 6000 sites. Extreme Gradient Boosting (XGBoost) models revealed that climatic factors are more important predictors of trends in game fish catches than nuisance factors (sampling gear, time), lending support to collating other heterogeneous datasets for analyses. Mean annual temperature and precipitation were the most important drivers of species catches. Fish thermal preference guilds predicted primarily species responses to temperature, suggesting that warmer and wetter climates may not favour the same species. Despite the challenging nature of these datasets, XGBoost models provided excellent fit, predictive capacity, and interpretability, thereby illustrating that large, heterogeneous datasets can be used to inform freshwater fisheries management in a changing climate.

Common or European carp (Cyprinus carpio) were eliminated from Lake Winona during a 1973 lake reclamation project. Multiple efforts to prevent their return and eliminate spawning opportunities have failed. Carp have remained in the lake for the past 50 years, but more recent observations of spawning activity in the lake suggest that their numbers have increased. We used shoreline electrofishing data from Lake Winona (2005–2021), along with carp abundance and effects models, to estimate the abundance of carp in Lake Winona, and to evaluate the need for future carp management within the lake. Carp size (mean TL = 614 mm, mean weight = 3.42 kg) did not differ between eastern and western basins, but densities were three times higher in the western basin (105 compared to 34 fish/hectare), and carp had significantly higher relative weights in the western (117%) versus the eastern (107%) basin. Carp biomass estimates for the eastern (116 kg/hectare) and western (360 kg/hectare) basins suggest that the lake may soon experience significant declines in macrophyte cover and other ecological damage associated with that loss. With an estimated adult carp population of >6900 fish and a carp biomass (23,750 kg) 1.5 times greater than the biomass of all carp killed during the 1973 reclamation, carp management activities (e.g., fish removal and spawning migration barriers) should be initiated soon to protect the Lake Winona game fish community.