Local Fish Research Articles

Analysis on career aspirations and expectations of fishery-oriented learners on post-academic career directions

The fisheries industry holds significant value, both economically and ecologically, contributing to food security, employment, and sustainable resource management. By advocating for responsible consumption and supporting local fishers who prioritize sustainable methods, young people can help ensure the health of fish populations and aquatic ecosystems. This exploratory study analyzed the career aspirations of fishery-oriented students from Zamboanga City, Sulu, and Tawi-Tawi. Fisheries students (n=30) were purposively sampled to be interviewed. They were asked about how they perceived their career aspirations and how the program influenced their perceptions. The study revealed that the quality of experience in the fisheries education program significantly influences students’ career aspirations. Effective program implementation leads to increased student engagement in the fisheries industry. Students with extensive laboratory experience were more likely to pursue laboratory-based careers, while exposure to global issues like overfishing and climate change motivated them toward sustainable fisheries management. Hands-on training and practical experiences, including fieldwork and laboratory projects, enhance students' competencies and confidence, preparing them for real-world challenges. Essentially, a positive learning environment fosters both skill development and professional aspirations among students, ultimately shaping their career paths in the fisheries sector.

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

Seasonality in fisheries is known when opening and closing dates are established, but it is much less defined in places lacking seasonal regulations. Highlighting fisheries seasonality is critical because, for one, it can influence seafood supply and prices. Here, we examine fisheries seasonality by analyzing extensive datasets of monthly commercial landings and prices spanning over twenty years for 22 major finfish stocks in Kuwait, where seasonal closures are uncommon. Additionally, we develop a questionnaire to obtain information from the recreational fishery—the only fishing sector composed of local fishers—to investigate whether peak commercial landing months overlap with local fishers’ knowledge. We found a distinct seasonality in finfish commercial landings: at the two ends of the spectrum, the strongly winter-spring finfish landings (60% or more of landing proportions), which plummet sharply over warmer months, and the strongly summer-fall finfish landings. Landings influenced seasonal mean prices, with higher landings generally meant lower prices and vice versa. Further, we found that months identified by local fishers as being the “best fishing seasons” are consistent with months of peak landings for most stocks, though fishing seasons for a few stocks diverged widely from seasonality in commercial landings. Broadly, our analysis underscores high seasonality unrelated to seasonal regulations and supports combining commercial landings and local fishers’ knowledge to understand fishery and finfish seasonality, particularly in data-limited situations.

Analysis of Waters Physical Condition in Small Pelagic Fishing Location (Case Study at Fisheries Management Area (FMA) 715)

The aim of research is to study the physical conditions at the small pelagic fishing locations relation with the ideal criteria for small pelagic fish habitat. In this research, physical parameters consist of temperature and chlorophyll-a will be analyzed according to conditions at the actual small pelagic fishing location in FMA 715 throughout 2018. The actual small pelagic fishing location is obtained from the fishing logbook data which is validated with the Vessel Monitoring System (VMS) data using Kernel Density Interpolation. Sea surface temperature (SST) and chlorophyll-a information at small pelagic fishing locations are extracted through MODIS Imagery. Small pelagic fish species at the fishing location are caught for Shortfin Scad, Trevally, Yellowstrip Scad, and Shadow Trevally. The results showed that the surface temperature at the small pelagic fishing location in FMA 715 is 21.56 - 31.75 oC and chlorophyll-a concentration is 0.08 - 1.33 mg/m3. It can be concluded that the physical conditions at the small pelagic fishing location are not always in accordance with the ideal habitat conditions. The conditions of sea surface temperature and chlorophyll-a that are close to the ideal conditions for small pelagic fish habitat are in the East Season.

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.

Associations between iKaluk/Arctic charr (Salvelinus alpinus) and estuarine benthic diatom habitats in nearshore Nunatsiavut waters

iKaluk, Inuttitut for Arctic charr (Salvelinus alpinus), holds significant commercial and cultural value for Inuit communities throughout Nunatsiavut. Studies evaluating iKaluk habitat associations in freshwater are plentiful; however, there is limited information on the ecological makeup and sediment characteristics of anadromous charr habitats in marine environments. This study investigated the benthic associations of Arctic charr during their marine residency period in Nain, Nunatsiavut, using underwater videos, harvester-identified fishing locations, and acoustic telemetry. Drop-camera surveys were deployed on previously placed hydrophone acoustic receivers and within harvester-identified fishing locations to describe and quantify available benthic habitats in the study area. Telemetry information was used to identify charr occupancy hotspots, and calculate habitat suitability indices. A total of 248,056 benthic organisms belonging to 63 morphotaxa were identified within the 125 video drops used for benthic community characterization and these represented five faunal assemblages. Marine phase charr occupied estuaries to a greater degree than other fjord or coastal headland environments and these habitats were typically characterized by fine sediments covered by high densities of brittle stars (Ophiuroidea spp.) and benthic diatom mats. The consistent presence of diatomaceous sediments is indicative of abundant foraging opportunities. The importance of these habitats to iKaluk, need to be considered in future marine planning given the cultural and ecological value of this species to many northern communities that face growing threats from environmental change.

Analysis of Kidney Tissue Keting Mystus gulio (Hamilton, 1822) in Gembong and Rejoso River, Pasuruan, Indonesia

Mystus gulio is a local fish that can open up opportunities for the community. Pollution causes water quality to decrease. Fish are an important indicator in the aquatic environment, Histological analysis can be said to have a function as a natural biological sign to determine the health condition of fish which can be seen from changes in tissue structure in organs exposed to pollutants. Organs that’s vulnerable to water pollution is kidneys. Kidney tissue is susceptible to damage because kidneys function as a means of filtration and excretion, The method used in this research is descriptive method. Fish were caught from river than dissected to remove the kidneys for histopathological analysis using the HE method, analyzed using the scoring method. The results obtained in both rivers were that fish kidneys caught in the Gembong River were categorized as moderately damaged, while fish kidneys caught from the Rejoso River were categorized as lightly damaged. This is in line with the results of the heavy metal lead from both rivers. Where the yield of lead in fish kidneys caught from the Gembong is on average higher than the yield from fish kidneys caught from the Rejoso.

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.

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.

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.