Local Fish Research Articles

Persistence and connectivity of in-channel waterholes in the Darling (Baaka) River - An analysis using satellite imagery and graph theory.

In-channel persistent surface water provides critical refuge habitat for aquatic organisms in intermittently flowing rivers. Quantifying the flows that maintain connectivity among persistent waterholes is important for managing river flows to maintain refuges, improve their quality and facilitate connectivity and nutrient and energy transport. This study aimed to quantify spatial and temporal waterhole persistence and connectivity in a 664km reach of the Darling River in Australia's Murray-Darling Basin. A 35-year satellite imagery record and graph theory were combined to produce a time series of spatial graphs. Persistent in-channel waterholes represented nodes on the graph, with vertices reflecting connectivity during flow events. Models were developed to quantify temporal variation in connectivity in relation to environmental predictors at a reach scale and at specific waterholes. Connectivity was highly spatially variable and clearly impacted by flow interception at in-channel weirs. Several highly connected waterholes were identified as both hub and stepping stone habitats in the connectivity analysis, indicating that they may serve important ecological functions for both local and large-scale fish dispersal. Flow was the most influential predictor of reach-scale connectivity, followed by local rainfall. An analysis of specific waterholes found that following a reconnecting flow event, flow above the 75th percentile was required to maintain full connectivity of the most disconnected/isolated waterhole. This study demonstrated that connectivity can be predicted using variables including flow, rainfall, and antecedent climate conditions, thereby highlighting the usefulness of this technique for predicting connectivity under a range of flow scenarios.

Contrasting hair mercury in fishermen and workers of fish industry of Marano Lagunare (Upper Adriatic Sea), a coastal lagoon area contaminated by mining and industrial activities, against residents from the Dolomites Alps.

This survey aimed at estimating the concentration of hair mercury (Hg) in fishermen and workers of fish industry of Marano Lagunare (North-eastern Italy, Upper Adriatic Sea). A field investigation was conducted from 2nd of December 2023 through 18th April 2024, on 73 local fishermen, 83 workers of fish industry and 93 controls among residents (mainly farmers/herdsmen) of the Dolomites Alps. An amount of approximately 100mg of hair was collected from all respondents, who were also asked to fill out a self-administered questionnaire collecting socio-demographic and lifestyles information. The median hair Hg concentration was 2.56mg/kg in fishermen, 2.31mg/kg in workers of fish industry and 0.58mg/kg in controls. Compared with controls from the Dolomites, log-transformed hair Hg increased linearly with the amount of fish consumed (>1 meal per week), consumption of fresh fish and was significantly higher in fish dealers/fish restaurateurs and fishermen, regardless if operating on open sea or lagoon. All study groups but fish farmers and local residents involved in other business exhibited significantly higher odds of hair Hg >2mg/kg at multiple logistic regression analysis. Whilst above the threshold background exposure recommended by WHO for the general population, the median levels of hair Hg in fishermen and workers of fish industry of Marano Lagunare were still below the cut-off of no health effects observed on human health (11.5 mg/kg). The above evidence most likely reflects contamination of lagoon bed and respective tributary river beds by sedimentary Hg from mining and industrial activities, with subsequent transfer of the metal into the aquatic trophic chain and from there to humans through consumption of local fish.

Production of MANGANTA Tuna Shredded Fish

ABSTRACT Indonesia, as a maritime country, has abundant fishery resources, including in Lhokseumawe City, Aceh Province. Tuna and cob are the dominant fish species in Gampong Ujong Blang, Banda Sakti District, a key fishing center. However, excessive fish catches often exceed local demand, forcing fishermen to distribute them to nearby areas like Lhoksukon and Bireun. Those without delivery access struggle to sell their catch, leading to spoilage. Meanwhile, local fish processing industries lack facilities and knowledge to enhance fish value, resulting in tuna being consumed quickly before quality declines. To address this, processing tuna into shredded products presents a viable solution. "MANGANTA" shredded tuna offers a cheaper, lower-cholesterol alternative to beef floss. Enhanced with regional spices and fish meat separator technology, it has the potential to become an Acehnese food icon, creating business opportunities while addressing challenges faced by fishermen and processors. Keywords: Shredded tuna, MANGANTA, food technology, Acehnese spices, fish meat separator, innovation, fisheries industry.

Variations of Length–Weight Relationships for Six Fish Species from the Lower Yarlung Zangbo River Catchment, Tibet, China

The lower reaches of the Yarlung Zangbo River are one of the most important biodiversity hotspots worldwide. With the rapid economic development in the area coupled with global climate change, the fish resources and diversity of this region are experiencing serious threats. Basic biological information on most fishes in the river is limited, restricting the conservation of local fish resources. This study aimed to provide estimates of length–weight relationships (LWRs) for six fish species from the lower Yarlung Zangbo River catchment, Tibet, China. From 2023 to 2024, 4034 specimens belonging to two families, five genera, and six species were collected using various types of fishing techniques. The LWRs of five species, namely Schizothorax curvilabiatus, Schizothorax molesworthi, Pseudecheneis sulcata, Parachiloglanis hodgarti, and Exostoma labiatum were reported for the first time to FishBase, except Garra tibetana. The b values calculated from the LWRs ranged between 2.738 and 3.172, and the r2 values for all LWRs estimates ranged from 0.931 to 0.989. Sexual variations of LWRs were observed in S. molesworthi and P. sulcata; seasonal variations were detected in S. curvilabiatus, S. molesworthi, G. tibetana, P. sulcata, and P. hodgarti; and geographical differences were discovered in S. molesworthi, G. tibetana, P. sulcate, P. hodgarti, and E. labiatum. Additionally, this study updated information for FishBase by providing a new record of maximum standard length for S. curvilabiatus, S. molesworthi, G. tibetana, and P. hodgarti and a new record of total length for P. sulcata. The findings of this study are essential for the management and conservation of locally indigenous fish and fisheries.

Herons in Aquafarms Are More Fearful of Humans.

Herons (Ardeidae), an important group in wetland ecosystems, have a particularly strong relationship with humans. However, their predation on farmed fish and shrimp in aquafarms can lead to economic losses for local fish farmers. Consequently, notable conflicts arise between fish farmers and herons. Fish farmers adopt various measures to deter herons from "stealing" their fish; however, there is limited research on the behavioral responses of herons under such pressures of human disturbance. Flight initiation distance (FID) is an important manifestation of avian anti-predation behavior and serves as an indicator of birds' tolerance to human disturbance. This study investigated the potential variations in tolerance to human disturbance between the little egret (Egretta garzetta) and the Chinese pond heron (Ardeola bacchus) in "stealing" environments (aquafarm environments) and non-aquafarm environments in Hainan and Guangdong Provinces, south China, using FID as an indicator. Herons in aquafarm environments were less tolerant (having longer FIDs) to human disturbance compared to herons in non-aquafarm environments. The main cause of this phenomenon could be the harsh deterrents used by humans to prevent herons from "stealing" fish. These deterrents increase the predation risk for herons when "stealing" in aquafarms, causing them to exhibit less tolerance to human disturbance. Our study increases understanding of the behavioral response patterns of herons in human-wildlife conflicts and provides valuable insights for more scientific and rational management and protection of Ardeidae species.

Identifying unregulated fisheries seasonality through commercial landings and local fishers’ knowledge

Identifying unregulated fisheries seasonality through commercial landings and local fishers’ knowledge

Downscaling global reference points to assess the sustainability of local fisheries.

Multispecies coral reef fisheries are typically managed by local communities who often lack research and monitoring capacity, which prevents estimation of well-defined sustainable reference points to perform locally relevant fishery assessments. Recent research modeling coral reef fisheries globally has estimated multispecies sustainable reference points (i.e., the maximum reef fish yields that can be harvested sustainably and the corresponding reef fish standing biomass at which those are expected to be achieved) based on environmental indicators. These global reference points are a promising tool for assessing data-poor reef fisheries but need to be downscaled to be relevant to resource practitioners. Using a small-scale multispecies reef fishery in Papua New Guinea, we estimated sustainable reference points and assessed the sustainability of the fishery by integrating global-scale analyses with local-scale environmental conditions (i.e., coral cover, sea surface temperature, ocean productivity, and whether the reef is an atoll), reef area, fish catch and standing biomass estimates, and fishers' perceptions. Local-scale relevant data were obtained from a combination of remote sensing products, underwater visual censuses, catch surveys, and household structured social surveys. Our sustainability assessment based on downscaled estimated sustainable reference points was consistent with local fishers' perceptions. Specifically, our downscaled results suggested that the fishing community was overfishing their reef fish stocks and stocks were below biomass levels that maximize production, making the overall reef fishery unsustainable. These results were consistent with fisher perceptions that reef fish stocks were declining in abundance and mean fish length and that fishers had to spend more time finding fish. Our downscaled site-level assessment revealed severe local resource exploitation, the dynamics of which were masked in national-scale assessments, emphasizing the importance of matching assessments to the scale of management. Overall, we show how global reference points can be applied locally when long-term data are not available, providing baseline assessments for sustainably managing previously unassessed multispecies reef fisheries around the globe.

Microplastics in pelagic and demersal fishes from the Meghna River estuary, Bangladesh

Microplastics (MPs) were investigated in four fish species viz., paradise threadfin (Polynemus paradiseus), corsula mullet (Rhinomugil corsula), flathead sillago (Sillaginopsis panijus) and king gobyeel (Taenioides sandwipi), which were collected from the Meghna River estuary in Bangladesh. The gastrointestinal tracts (GITs) of fishes (n = 80 in total) were examined for the presence of MPs following alkali digestion, microscopic observation and μ-FTIR analysis. A total of 573 MPs were detected across all four fish species, indicating the presence of MPs in 81.3% of the fish samples. On average, there were 7.16 ± 4.33 MP items/fish, 2.16 ± 1.76 items/g of GIT and 0.15 ± 0.12 items/g of body weight. Polyethylene, polypropylene and nylon were the most abundant polymers, comprising 47%, 23% and 19%, respectively, according to μ-FTIR analysis. The majority of MPs were fibers (62.48%), with white being the dominant color. R. corsula demonstrated the highest number of MPs in the < 500 μm size range, suggesting that smaller particles are more bio-available to pelagic fish. The findings confirm the contamination of the Meghna River estuary by MPs, and their presence in local fish raises concerns about potential public health risks through the food chain.

10-Years of imagery from a cabled-observatory reveals a decreasing trend in coastal fish biodiversity.

Monitoring the effects of climate change and other multi-years processes on coastal ecosystems require long-term datasets that may extend into decades. One tool to achieve this are cabled seafloor observatories that can collect continual streams of environmental and biological data as long as the equipment is maintained. Here, we used 10-years of time-lapse images (every 30 mins) from the OBSEA seafloor cabled observatory located at 20m depth, four km offshore from Vilanova i la Geltrú (Spain) coast, to characterize temporal trends in fish community dynamics. These temporal trends were compared to in situ and remotely-sensed (MODIS-Aqua) data on temperature, salinity, and chlorophyll-a concentration (Chl-a). We observed a reduction in fish diversity over time and an increase in species turnover. Specifically, there was a decrease in the relative abundance of fish species at the lowest trophic levels alongside an increase in predators, suggesting a top-down effect. Of temperature, salinity, and Chl-a, only salinity exhibited a significant change over time. Nevertheless, the Generalized Additive Models (GAMs) revealed significant correlations between fish biodiversity indices and both temperature and Chl-a. Following models results we concluded that environmental variables affected the local fish community only at seasonal level. Including more environmental variables, such as fishing activity and pollution, in the applied models may help explain the detected decreases in biodiversity.

Widespread presence of metallic compounds and organic contaminants across Pacific coral reef fish.

Coral reef fishes represent an invaluable source of macro- and micro-nutrients for tropical coastal populations. However, several potentially toxic compounds may jeopardize their contribution to food security. Concentrations of metallic compounds and trace elements (MTEs), and persistent organic pollutants (POPs, including pesticides and polychlorobiphenyls PCBs), totalizing 36 contaminants, were measured in coral reef fish from several Pacific islands. The objective of this study was to describe the spatial distribution of these compounds and contaminants in order to identify potential variables explaining their distribution at a Pacific-wide scale. To achieve this, we applied Boosted Regression Trees to model species-specific and community-level contaminant and inorganic compound concentrations at the scale of the tropical Pacific Ocean. Overall, using 15 easily accessible explanatory variables, we successfully explained between 60 and 87% of the global variation, with fish body size being the most important correlate of MTEs and POPs concentrations in reef fish. Our modeling approach allowed us to estimate and map the distribution of the community-level concentration of 19 contaminants and inorganic compounds at the scale of the equatorial and south Pacific Ocean. Spatial patterns varied significantly depending on the compound, with modeled quantities per 100g of fish flesh generally being higher in the central and southwest Pacific than in the eastern part of the basin. These patterns were influenced by a combination of biological, environmental, anthropogenic and biogeographical variables. Overall, this approach represents an important step toward the estimation of concentrations of the main compounds on the basis of species identity and fishing location. Our results enhance our understanding of the extent of contamination in the Pacific while underscoring the urgent need for long-term and large-scale spatial monitoring of diverse compounds in this region.

Indirect Effects and Context Dependency in Stream Fish Invasions

ABSTRACTAimInvasion ecology is replete with a body of well‐supported yet contradictory evidence for numerous invasion hypotheses, likely as a result of context dependency. Context dependency in invasion studies can arise in two ways: (1) apparent, when results differ between studies solely due to methodical differences, or (2) mechanistic, when results truly differ due to ecological processes. One form of apparent context dependency occurs when causally linked factors associated with invasion success (hereafter, invasion drivers) either mask or enhance each other's effect on invasion success. Mechanistic context dependency can occur when regional scale processes modify the influence of local scale invasion processes. Together, apparent and mechanistic context dependency likely give rise to conflicting support between invasion hypotheses via confounding effects of causally related invasion drivers and region‐specific invasion processes.Location2339 stream segments in two ecoregions of the United States.MethodsUsing local scale stream fish community data for two distinct ecoregions, we constructed identical path models to estimate the direct and indirect effects of invasion drivers on nonnative richness. We chose one variable to index invasion drivers from each of the following categories: propagule pressure, natural abiotic, anthropogenic abiotic and biotic factors.ResultsWe found evidence of apparent context dependency through the presence of indirect effects, in which the effects of propagule pressure and biotic factors on nonnative richness were modulated by abiotic factors. The indirect effects of invasion drivers differed between both regions, providing evidence of mechanistic context dependency.Main ConclusionsApparent and mechanistic context dependency can lead to conflicting evidence between studies of invasion hypotheses. Accounting for indirect effects of invasion drivers is important in gaining a more general understanding of the invasion process. Furthermore, because indirect effects varied regionally, it is important to understand the large‐scale processes that contextualise local invasion processes.

HIERARCHICAL MODELS OF FISH ABUNDANCE AND OCCURRENCES IN SOUTHERN BASIN OF KAINJI LAKE NIGERIA

Fish abundance is directly linked to species diversity, indicating the importance of maintaining rich fish communities for ecosystem stability and productivity. The aim of the study is to fit hierarchical models to modelled fish abundance through the following objectives: Evaluate fish abundance and occurrences using abundance formulae and their diversity index, fit hierarchical models, Investigate the variability of fish abundance and occurrences in different fishing locations and to identify the consequences of location specific management actions. Shannon weinner and Sampson diversity index reveals that Monai fishing location has the highest percentage of catch ranging to 30%. Cast net is found to be the most efficient method with highest count value of 1.9457, Poisson and negative binomial models reveal that, the locations have no significant difference and there is variability among fish catch over the years. Negative binomial reveals that Monai has the highest fish in abundance having the fish count value of 1.067 with a decrease in fish population by 7%. These results indicate significant variations in fish abundance and occurrence across the locations, years and methods. From the comparative regression and negative binomial model. Negative binomial model has the lowest log like hood of 7855874.07, with a deviance of 434.34. This infers that the negative binomial regression performs better than the Poisson regression in modelling fish abundance and occurrence. This study contributes valuable knowledge about dynamics of fish populations and basis for informed decision making in fisheries management and conservation.

지속가능한 비즈니스모델을 통한 가방디자인 연구 - 페그물 업사이클링 KOOK 브랜드 제품을 중심으로

Along with the aging population of local fishing villages and the decrease in fishing income due to job losses, the problem of fishing net waste accumulated on the coast is becoming a discouraging factor for the environment and marine tourism. Due to the aging and declining population of fishing villages, there is a shortage of manpower to collect this waste, making it imperative to solve fundamental problems related to cost reduction for maintaining a pleasant environment and waste disposal. This issue can be partially addressed by using yarn extracted from waste nets in fishing villages to produce upcycled products. Additionally, this initiative will create jobs that can help increase the income of fishing villages, where the dominant population consists of seniors. By carrying out the commercialization process using waste nets in a social economic manner, we believe that a virtuous cycle business model can be established, leading to community problem-solving and job creation, along with effective design development through the process of recognizing and resolving various issues in the local community. If a business model such as “KOOK” is established and specialized products suitable for regional characteristics are developed, a social contribution business model can be created alongside effective design development while addressing various challenges faced by the local community.

Overfishing of Threatened Bycatch Species in a Marine Protected Area: The Elasmobranchs of Banc d'Arguin, Mauritania

ABSTRACTElasmobranch (rays and sharks) populations are vulnerable to overexploitation due to their slow growth, late maturity, and low fecundity. Industrial fishery impacts on sharks and rays are known, whereas impacts of artisanal fisheries are less understood. We quantified catches of sharks and rays in artisanal fisheries at the Parc National du Banc d'Arguin (Banc d'Arguin), Mauritania (West Africa) during 1998–2020, a period when fishing effort increased around 2006, catches increased, but catch‐per‐unit‐effort declined substantially. Shark nets and meagre fixed gill nets were used to catch elasmobranchs, with catches comprising over 60% of elasmobranch species. Therefore, elasmobranchs were not bycatch, but rather, the target of fisheries. Of 33 elasmobranch species captured, 94% of shark species and 76% of ray species are threatened with extinction. We recommend that management approaches should focus on fishing locations with the highest occurrence of threatened elasmobranch species in catches, through new regulations on fishing gear types and discouragement of trade in elasmobranch products from Banc d'Arguin.

Digestive Enzymatic Activity Profiles and Larval Growth Performance of Barramundi, Lates calcarifer (Bloch, 1790), From Indonesia and Australian Broodstocks

Barramundi is one of the most important marine commodities, with cultivation challenges closely related to survival and growth factors. There is still a lack of information on digestive enzymatic activity profiles and larval growth, and the use of Australian brooders rather than local Indonesian brooders is still frequent. The objective of this study is to investigate the profile of digestive enzymatic activity profiles and their correlation to the growth performance of Barramundi larvae, Lates calcarifer (Bloch, 1790), originating from Indonesia and Australia. The activity profile of digestive enzymes was evaluated using real-time quantitative polymerase chain reaction (RTqPCR). Fish larvae were reared till day 20 to measure growth in weight, length, and survival During the observation period up until the day 20, the length and weight growth of Australian fish larvae were greater than that of the local Indonesian. Analysis of the activity profile of digestive enzymes also revealed that Australian fish larvae had greater activity than Indonesian fish larvae, which was positively correlated with the length and weight of fish larvae, despite the fact that growth rates and survival rates of local fish larvae from Indonesia and Australia were comparable by the end of the d-20 phase.

Effect of Drying Medium on Proximate and Mineral Composition of Croaker Fish peculiar to the Coastline of Akwa Ibom State, Nigeria

The study investigated the nutritional composition of dried croaker (p. typus) fish from the coastline of Eastern Obolo, Ibeno, Ikot Abasi, and Mkpat Enin Local Government Areas of Akwa Ibom State, in Southern Nigeria. It compared the quality of fish dried in a traditional roadside dryer commonly used by local fish vendors with that of fish dried in an active solar dryer designed for agricultural products. The results revealed significant differences (p &lt; 0.05) in the proximate composition of the fish from the two drying methods. The ash content, crude fiber, and lipid were higher in the conventionally dried samples compared to the products from the solar dryer. Furthermore, the protein content was slightly higher in the products from the active solar dryer (47.67±0.17 %) than in those from the conventional dryer (43.33±0.19 %). These findings suggest that the product from the active solar dryer may help reduce the risk of high blood pressure and promote a healthier diet. Carbohydrate levels were higher in the samples from the conventional roadside dryer (4.13±0.02 %) than in the products from the solar dryer (3.74±0.03 %). The energy level was also higher in the solar-dried samples (3.74±0.03 %) compared to those from the conventional dryer (430.33±0.34 Kcal). These differences were attributed to factors such as exposure of the product to impurities and the nature of the drying medium. Additionally, the study found that the macro elements (Sodium, Potassium, Calcium, Magnesium, and Sulphur) were present in higher concentrations in products from the conventional dryer than in those from the active solar dryer. The mineral composition of the samples from the two methods also exhibited significant differences (p &lt; 0.05). The study recommended the consumption of these products based on their low toxic levels.

Sayılarla balıkçılık: Muara Kintap balıkçılığını veri odaklı balıkçılık alanı tahmin haritalarıyla güçlendirmek

The paper aims to enhance the fishing efficiency and sustainability of Muara Kintap fishers by using data-driven Fishing Area Forecast Maps (FAFM). This study makes significant contributions to the field of fisheries management by demonstrating the effective use of satellite data for local-scale fisheries management, bridging the gap between scientific research and practical applications, as well as promoting sustainable fishing practices and improving the fishers' livelihoods. The research ingeniously combined the wisdom of local fishers captured through the Fishing Points app with cutting-edge technology. Aqua MODIS satellite imagery captured detailed Muara Kintap waters condition, revealing sea surface temperature (SST) between 28.4 °C and 29.7 °C and chlorophyll-a (Chl-a) concentrations ranging from 0.38 to 6.27 mg/m³. The results strongly indicate that the distribution of Chl-a is a more influential predictor of fish catch than SST. This discovery underscores the intricate relationship between marine parameters and fish distribution. By providing FAFM, informed by Chl-a data, the fishers were able to make data-driven decisions, optimizing catches and promoting the long-term sustainability of their livelihoods. The study's impact transcends data analysis, highlighting the importance of collaboration and knowledge sharing among researchers, fishers, and policymakers in fostering sustainable fishing practices in Muara Kintap and beyond.

GROWTH AND SURVIVAL OF SPINY LOBSTER, Panulirus homarus JUVENILES FED WITH DIFFERENT FORMULATED FEEDS

Article Highlights- Indonesia has remarkable natural resources of spiny lobster Panulirus homarus and an exceptional opportunity to establish the largest lobster aquaculture industry in the world.- However, culturing lobsters still relies on natural feeds (trash fish of fresh fishery by-catch) which are inefficient and environmentally unsustainable.- Developing formulated feed based on locally available ingredients is invaluable for replacing natural feeds to support sustainable lobster culture.- Formulated feed made of local fish meal provided the best growth of juvenile spiny lobster Panulirus homarus compared to imported fish meal. AbstractSeveral studies suggested that good growth performance and survival of lobster juveniles can be achieved by feeding the lobsters with formulated feeds. This study aimed to (1) evaluate the growth and survival of spiny lobster Panulirus homarus juveniles fed with different diets having profiles based on a basal diet formulation and (2) to compare the growth of lobsters fed with an identical formulated feed with variations only in sources of fish meal and dry matter content. The feeding experiment was designed following a completely randomized design (CRD) with five diet treatments and five replicates for each treatment. Five experimental diets were prepared in this experiment, i.e., Diet A (basal diet prepared as moist pellets); Diet B (moist pellets with the same formulation as Diet A, using local fish meal); Diet C (moist pellets with the same formulation as Diet A, using imported fish meal); Diet D (dry pellets with the same formulation as Diet A, using imported fish meal); and Diet E (fresh fish). Juveniles of spiny lobster with an average weight of 3.00±0.07 g were allocated in 25 net cages (60 x 60 x 60 cm) placed in a circular HDPE canvas tank (7.5 m in diameter) at a density of 15 lobsters/cage in a flow-through seawater system. The juveniles were fed with the experimental diets twice/day for 12 weeks. The experiment showed that the best growth was observed in juveniles fed with moist feed containing local fish meal (Diet B) with the final weight reaching 18.74±2.30 g. Moist feed containing imported fish meal (Diet C) resulted in a higher survival rate (46.66%), and the lowest survival rate (13.33%) was obtained from juveniles fed with fresh fish (Diet E).

First record of the blue-and-yellow grouper Epinephelus flavocaeruleus (Lacepède 1802) (Perciformes: Epinephelidae) from the Borneo waters, Malaysia

Groupers of the family Epinephelidae constitute a diverse and commercially valuable group of reef fishes globally. They comprise an assemblage of carnivorous marine fishes, comprising more than 177 species across 16 genera. The epinephelid genus Epinephelus, which consists of over 90 species, is found worldwide in the tropics and subtropics. To date, the ichthyofauna of Malaysia has documented a total of 43 epinephelid species. Apart from these, Epinephelus flavocaeruleus (Lacepède, 1802), commonly known as the blue-and-yellow grouper, is rarely reported in the Indo-Pacific Ocean. The present study extends the documented distribution range of E. flavocaeruleus eastwards from the Andaman Sea to the Borneo waters of Sabah, Malaysia. Five specimens of the blue-and-yellow grouper were collected from a local fish market. Species identification was confirmed by the color patterns and DNA barcoding of 630 base pairs of the cytochrome C oxidase I gene for all E. flavocaeruleus specimens, Epinephelus cyanopodus (Richardson, 1846), and 10 closely related Epinephelus species. The interspecies genetic distance ranged from 0.002–0.168. Results from the Templeton, Crandall, and Sing (TCS) haplotype network analysis and maximum likelihood phylogeny based on the COI marker indicate a close genetic relationship between E. flavocaeruleus and E. cyanopodus. However, we refrain from proposing any taxonomic revisions given that more in-depth studies using multiple molecular markers or phylogenomic analysis on a larger sample size are necessary to confirm the taxonomic status of both species. This study significantly contributes to a better understanding of the taxonomy, phylogenetic relationship, and genetic diversity of E. flavocaeruleus.

Urinary level of 1,2-dichloroethane and its effects on blood biochemical markers among outdoor workers exposed to air pollution in Thailand.

Air contamination by 1,2-dichloroethane (1,2-DCE) is recognized as a threat across countries. Addressing this problem is challenging due to the absence of clearly defined biological standards for monitoring 1,2-DCE exposure among humans. Moreover, studies on the impacts of 1,2-DCE exposure on human health are limited. The aim of this study was to determine the level of 1,2-DCE in urine-separated into the health behavior and occupation groups-as well as its effects on blood biochemicals among overall 200 outdoor workers, with 50 working in each of the following four occupations: fishers, street vendors, public bus drivers, and traffic police in an environmentally polluted community in Thailand. The subject's behaviors were categorized into four groups: desirable health behaviors (non-smokers and non-drinkers), non-smokers who consume alcohol, smokers who do not consume alcohol, and undesirable health behaviors (frequent smokers and alcohol consumers). Data were collected at the end of the workday using interview forms, urine, and blood samples. Urine was analyzed for 1,2-DCE, and blood was analyzed for complete blood count (CBC), liver, and kidney function enzymes. Data were analyzed using the Dunnett's test, Kruskal-Wallis H test, and independent sample t-test according to statistical conditions. Our findings revealed that the median urinary 1,2-DCE level was 0.080 mg/L (0.022-0.462 mg/L). Subjects with undesirable health behaviors had a significantly higher urinary 1,2-DCE level (0.108 mg/L) compared to those with desirable health behaviors (0.056 mg/L), with a p-value of 0.009. Among bus drivers and local fishers, the dose of exposure was strongly associated with creatinine levels (p = 0.006). No significant association was observed between exposure dose and CBC across all groups. In conclusion, the urinary samples present a small variation in 1,2-DCE concentrations and thus can be used as a benchmark baseline value for monitoring exposure among outdoor workers in areas with intense air pollution. Kidney function markers can be considered in monitoring the health effects of 1,2-DCE.