Fisheries Management Strategies Research Articles

Temporal ecotrophic impacts of fisheries and climate change in the Aegean Sea

Mediterranean fisheries face a crisis with rapidly depleting stocks due to overexploitation, exacerbated by various stressors, including climate change, alien species and pollution. To address these challenges, modelling tools like ECOPATH with ECOSIM (EwE) are being used to assess marine ecosystems within the context of the ecosystem-based fisheries management (EBFM). In this study, an ECOSIM model was developed for the Aegean Sea based on a previously developed ECOPATH configuration (calibration period: 2006-2021; projection period: 2022-2050), to assess the current state of the food web and predict future conditions. Forecast scenarios incorporating fisheries and climatic stressors were explored to propose management measures that will ensure fisheries sustainability. The baseline simulation demonstrated a decline in biomass and catch in most functional groups (FGs). Fishing effort reduction scenarios led to biomass increase in several FGs, but resulted in lower catches. Climate scenarios with sea surface temperature time series from the Intergovernmental Panel on Climate Change triggered varied responses among FGs, with biomass gains observed in the demersal compartment, while the most negatively affected pelagic groups were mackerels and horse mackerels. Combined fisheries and climatic scenarios revealed synergistic effects, emphasizing the complex ecological interactions in the Aegean Sea. Ecological indicators from the ECOIND analysis highlighted losses in the demersal compartment in relation with the fisheries and climate scenarios, while trophic-based indices exhibited the most notable variations, suggesting cascading effects in the food web. The findings of this study will provide valuable insights for fisheries management and climate adaptation strategies in the Aegean Sea.

Comparative analysis of climate-induced habitat shift of economically significant species with diverse ecological preferences in the Northwest Pacific

The Northwest Pacific Ocean is the most productive fishing ground in the Pacific Ocean, with a continuous rise in water temperature since 1990. We developed stacked species distribution models (SSDMs) to estimate the impacts of climate change on the distribution dynamics of economically significant species under three climate change scenarios for the periods 2040-2060 and 2080-2100. Overall, water temperature is the most important factor in shaping the distribution patterns of species, followed by water depth. The predictive results indicate that all the species show a northward migration in the future, and the migration distance varies greatly among species. Most pelagic species will expand their habitats under climate change, implying their stronger adaptability than benthic species. Tropical fishes are more adaptable to climate change than species in other climate zones. Though limitations existed, our study provided baseline information for designing a climate-adaptive, dynamic fishery management strategy for maintaining sustainable fisheries.

Evaluation of ecological health of Hainan Island inshore waters in the South China Sea based on preliminary fish biotic integrity index (Actinopterygii and Elasmobranchii)

The well-being of marine ecosystems significantly influences biodiversity and ecological equilibrium amidst pressing challenges such as overfishing, water pollution, and climate change. Drawing upon data from two fishery stock surveys conducted in the inshore waters of Hainan Island in 2022, this study undertook a comprehensive evaluation of the marine ecosystem’s health status in the region. Employing the Fish Index of Biological Integrity (F-IBI) analysis method, coupled with an examination of the structural and functional aspects of the fish community, our research sheds light on the prevailing conditions. Our study revealed a spatial dichotomy within the fish communities of the study area and delineated them into two distinct groups: the northwestern and southeastern ones, with evident disparities in community structure between the two. By employing indicator screening and calculation, we segmented the fish health index in the inshore waters of Hainan Island into five tiers. Despite discernible anthropogenic influences, the ecological health of these waters remained generally robust. Notably, the mean F-IBI of fall (56.30) significantly exceeded that of spring (48.16) (P < 0.01). Furthermore, regarding spatial distribution, the ecological well-being of the southeastern waters surpassed that of the northwestern and Qionghzhou Strait waters. This study represents a pioneer endeavor to apply ecological health assessment methodologies towards informing resource management and conservation strategies for the inshore fisheries of Hainan Island. By furnishing a scientific foundation, our research contributes to the pursuit of sustainable marine ecological development within this locale.

Seasonal Distribution of Key Small-Sized Fish in the South Inshore of Zhejiang, China

Small-sized fish are a vital food source for large predatory commercial fish and play a key role in marine food webs, bridging lower and higher trophic levels. They are indispensable in maintaining the energy flow and material cycling within aquatic ecosystems. This study utilized bottom-trawl survey data from 2017 to 2020 along the south inshore of Zhejiang, China, complemented by concurrent environmental data, to examine the influence of environmental factors on the resource density and seasonal distribution patterns of four dominant small-sized fish species. The research findings indicated that SSH (sea surface height) and Chl (chlorophyll-a concentration) emerged as the key environmental factors influencing resource densities, with all four species exhibiting similar preferences toward these variables. However, significant disparities were observed in their preferences for SST (sea surface temperature), SSS (sea surface salinity), and DO (dissolved oxygen). The various species’ resource density and distribution patterns underwent significant seasonal variations. Additionally, the seasons and regions with the highest resource densities consistently aligned, occurring predominantly in autumn within the northern waters of the study area. This research further elucidated the environmental predilections and seasonal spatial distribution traits of small-sized fish in the south inshore of Zhejiang, an important feeding ground for economic fish species in the East China Sea. This provides scientific backing for forecasting alterations in coastal fishery resources under environmental and climate change scenarios and supports ecosystem-based fisheries management strategies.

Estimating the fishing rate for maximum nutritional yield (FMNY) optimizes fish production for human health

Abstract Fisheries management is largely based on the principle of achieving the maximum sustainable yield (MSY) with little regard for nutritional value. Management strategies maximizing nutrients rather than yield, however, may provide a smarter contribution to global food and nutrition security. Here, we present a novel fisheries management strategy: fishing at maximum nutritional yield (FMNY), the exploitation rate at which essential nutrients are maximized. Combining top-down population modelling approaches with bottom-up nutrient compositional analysis, we compared nutrient yields across seasons for Europe’s most valuable fishery (Atlantic mackerel, Scomber scombrus). FMNY estimates differed between nutrients, but were equal to, or lower than, FMSY. An autumn fishery provided higher amounts of lipids, omega-3 fatty acids, and protein, whereas vitamin D3, and calcium were maximized in winter. Aligning national fisheries policies and nutrition objectives is paramount to realising the potential of seafood in building healthier food systems. Developing novel fisheries management strategies, such as FMNY, where fisheries are optimised for human nutrition will, therefore, contribute to nutrient sustainability and help improve human health and diets.

Forecasting the Volatility of Tuna Fish Prices in North Sumatra using the ARCH Method in the Period January - April 2024

Tuna (Euthynnus affinis) is one of the most important fisheries commodities in Indonesia with significant economic value, especially in its contribution to fisheries export revenue. However, the price of tuna experiences significant fluctuations that can affect local and national economic stability. This study analyzes the daily price fluctuations of tuna in the North Sumatra market from January 1, 2024 to April 29, 2024 using a time series analysis approach. Daily price data were collected and analyzed to identify existing price patterns and volatility. The Autoregressive Conditional Heteroskedasticity (ARCH) model was selected to address the heteroscedasticity in the data, which suggests that the volatility of tuna prices can be well predicted based on past price behavior. The analysis steps include identifying the optimal ARCH model using the Autocorrelation Function (ACF) and Partial Autocorrelation Function (PACF), as well as testing parameter significance and normality assumptions to validate the model fit. The results show that the ARMA (1,0,0) model is the optimal one to model the price volatility of yellow tuna with the MAPE obtained of 2.382. compared to the ARMA-ARCH method with the MAPE value obtained of 2,747. Because it still contains heteroskedasticity effects, even though the results are good, the prediction results do not closely match the original data. The model is effective in improving price forecasting accuracy, which is important to support decision-making in risk management and economic planning in the fisheries sector. The findings contribute to understanding the dynamics of the yellowtail market and optimizing strategies for fisheries management.

Study of Hepatosomatic Index, Gonadosomatic Index and Fecundity of Tengra Fish (Mystus gulio)

The tengra fish (Mystus gulio) is an important commercial species found in the coastal regions of West Bengal, India and Bangladesh. M. gulio is an important species within its ecosystem and has significance in local fisheries. Its adaptability to both freshwater and brackish environments makes it a resilient species. This study investigated the hepatosomatic index (HSI), gonadosomatic index (GSI), and fecundity of M. gulio to better understand its reproductive biology. Specimens were collected monthly from the Meghna River estuary between February and June 2023. The GSI was found to be highest in August (9.95±0.15%), indicating the peak spawning season. The HSI showed an inverse relationship with GSI, being lowest in March. Fecundity ranged from 88,495 to 264,104 eggs, with a mean of 171,581±17,855. Fecundity was positively correlated with total length, body weight, and gonad weight. Statistical analysis revealed significant differences in GSI and HSI between sexes and age groups (virgin vs 1+ year). Regression models showed that fecundity was highly dependent on gonad weight (r2=0.809) compared to length (r2=0.047) and weight (r2=0.216). M. gulio is an important brackish water fish with good taste and nutritional value. While it is optimally exploited from the East Coast of India, its culture potential is being explored through polyculture experiments and research on seed production and farming techniques. These findings provide valuable insights into the reproductive dynamics of M. gulio and can inform management strategies for sustainable fisheries. However, further research is needed to fully understand the reproductive biology of this catfish across its range to inform sustainable management strategies.

Assessing extraterritorial fishing operations in Türkiye's Contiguous Zone: A decade of observations and implications for fisheries management in the Eastern

The protracted maritime jurisdictional disputes in Türkiye's EEZ in the Eastern Mediterranean have perpetuated economic disparities and engendered lacunae in fisheries management that could undermine marine biodiversity and regional collaboration efforts. This study interrogates the extent and frequency of extraterritorial fishing operations within the contiguous zone of Türkiye's territorial waters, with a particular emphasis on the years 2013 through 2023. Utilizing data acquired from Global Fishing Watch, the analysis delineates the monthly average fishing hours engaged by different gear types-namely small scale, trawl, undefined, and purse seine-across various neighboring countries, including Cyprus, Egypt, Greece, Italy, Libya, and Morocco. Findings reveal a persistent increase in fishing activities within these contentious waters over the observed period, reflecting a rise in the deployment of ship-tracking systems, which have potentially inflated reported fishing hours. This surge underscores the urgent need for comprehensive fisheries management strategies that harmonize economic pursuits with the preservation of delicate marine ecosystems. The study's methodology involved analyzing vessel movements via Marine Traffic and Global Fishing Watch data, assessing parameters such as fishing areas, periods, methods, and national affiliations. The results, illustrated in Tables and Figures without direct citation due to the aggregative nature of the data, show varied patterns of fishing activities. The significant increase in Türkiye's trawl fishing hours in 2022, peaking at 857.29 hours, underscores the intensification of certain fishing practices in the region. The need for resolving international disputes is pivotal for establishing effective fisheries management in the Eastern Mediterranean. The findings advocate for enhanced diplomatic endeavors and cooperative governance among littoral nations, supported by international entities to ensure sustainable exploitation of marine resources and to bridge management gaps illuminated by this decade-long empirical inquiry.

The dynamics of social-ecological interactions in the PAAP (fisheries access management area) Taluk Lasolo Region, North Konawe Regency, Southeast Sulawesi Province: A comprehensive approach to sustainable renewal

Abstract This research aims to study the dynamics of social-ecological interactions in the Teluk Lasolo PAAP (Fisheries Access Management Area) in North Konawe Regency, Southeast Sulawesi Province. The study adopts a comprehensive approach to sustainable development, utilizing Social-Ecological Network Analysis (SENA). The Teluk Lasolo PAAP area is a complex environment with small-scale fisheries as a crucial component of the coastal ecosystem. Using the SENA method, this research analyzes the interactions between social and ecological dimensions in the context of fisheries management based on access rights. The study also considers economic aspects, governance, and resource utilization within the social-ecological network. The case study is conducted in the Teluk Lasolo area to understand the complex dynamics among various stakeholders, fishing communities, and the coastal ecosystem. The findings of this research will provide profound insights and knowledge about the factors influencing the sustainability of small-scale fisheries and offer recommendations for sustainable updates in fisheries resource management in the region. In conclusion, this research highlights the importance of a comprehensive approach involving social-ecological interactions in managing small-scale fisheries. The results of this study are expected to make a positive contribution to the development of sustainable fisheries management strategies in the Teluk Lasolo PAAP area and other coastal regions. Kata kunci : Kawasan PAAP Teluk Lasolo, Jejaring Sosial-Ekologi, Perikanan Skala Kecil, Pengelolaan Perikanan Berbasis Hak akses Perikanan.

Genomics resources for the Rapa Nui (Eastern Island) spiny lobster Panulirus pascuensis (Crustacea: Decapoda: Achelata)

BackgroundThe Easter Island spiny lobster Panulirus pascuensis (Reed, 1954) or ‘Ura’ in the Rapa Nui language, is a little known species native to the south eastern Pacific Ocean, distributed along the coasts of Easter Island, Pitcairn Island, and the Salas y Gómez Ridge. In Easter Island, P. pascuensis is the target of a small and profitable and probably overexploited fishery. In this study, we profited from a series of bioinformatic analyses to mine biological insight from low-pass short-read next generation sequencing datasets; we have estimated genome size and ploidy in P. pascuensis using a k-mer strategy, discovered, annotated, and quantified mobile elements in the nuclear genome, assembled the 45S rRNA nuclear DNA cassette and mitochondrial chromosome, and explored the phylogenetic position of P. pascuensis within the genus Panulirus using the signal retrieved from translated mitochondrial protein coding genes.ResultsK-mer analyses predicted P. pascuensis to be diploid with a haploid genome size ranging between 2.75 Gbp (with k-mer = 51) and 3.39 Gbp (with k-mer = 18). In P. pascuensis, repetitive elements comprise at least a half and a maximum of three fourths of the nuclear genome. Almost a third (64.94%) of the repetitive elements present in the studied nuclear genome were not assigned to any known family of transposable elements. Taking into consideration only annotated repetitive elements, the most abundant were classified as Long Interspersed Nuclear Elements (22.81%). Less common repetitive elements included Long Terminal Repeats (2.88%), Satellite DNA (2.66%), and DNA transposons (2.45%), among a few others. The 45S rRNA DNA cassette of P. pascuensis was partially assembled into two contigs. One contig, 2,226 bp long, encoded a partially assembled 5′ ETS the entire ssrDNA (1,861 bp), and a partial ITS1. A second contig, 6,714 bp long, encoded a partially assembled ITS1, the entire 5.8S rDNA (158 bp), the entire ITS2, the entire lsrDNA (4,938 bp), and a partial 3′ ETS (549 bp). The mitochondrial genome of P. pascuensis was 15,613 bp long and contained 13 protein-coding genes (PCGs), 22 transfer RNA (tRNA) genes, and two ribosomal RNA genes (12S ribosomal RNA [rrnS] and 16S ribosomal RNA [rrnL]). A phylomitogenomic analysis based on PCGs retrieved Panulirus pascuensis as sister to a fully supported clade comprising P. cygnus and P. longipes.ConclusionWe expect that the information generated in this study will guide the assembly of a chromosome-level nuclear genome for P. pascuensis in the near future. The newly assembled 45S rRNA nuclear DNA cassette and mitochondrial chromosome can support bioprospecting and biomonitoring of P. pascuensis using environmental DNA. The same elements can help to survey the public market place and detect mislabelling of this and other spiny lobsters. Overall, the genomic resources generated in this study will aid in supporting fisheries management and conservation strategies in this iconic spiny lobster that is likely experiencing overexploitation.

Using Fin Ray Elemental Signatures and Growth Zone Width to Estimate Onset of Sexually Maturity in Lake Sturgeon (Acipenser fulvescens)

Characterizing inter- and intra-population levels of variability in age at sexual maturation for long-lived fishes provides insight into year-class strength and recruitment dynamics, allowing for more effective management practices. Here we analyzed the ontogenetic chronology of pectoral fin ray annuli trace elemental concentration profiles as well as changes in annuli growth in Lake Sturgeon (Acipenser fulvescens) to determine onset of sexual maturity (OSM). Elemental concentrations and growth-zone width were used to build a random forest classification model to discriminate year-specific signatures to before or after OSM from 98 individual fin rays from both sexes across multiple populations and watersheds. The model demonstrated an overall accuracy of 98.8%. Ba was the most important variable related to OSM discrimination success followed by zone width, Pb, Mn, Mg, Zn, Cu, and Sr. Fin ray elemental concentrations began to increase at approximately age 24 (± 4.7) in females and 15 (± 3.1) in males while zone width decreased. This study implies that new applications for fin ray microchemistry are possible and could benefit future fisheries management strategies specifically by adding nonlethal or less invasive sampling techniques for evaluating OSM in sturgeon.

Krisis Biodiversitas Perairan: Investigasi Solusi Berbasis Komunitas untuk Pemulihan Ekosistem Aquatik

Crisis aquatic biodiversity is a critical environmental issue, triggered by human activities such as overfishing, pollution, and climate change, which have serious impacts on the stability of ecosystems and the climate change, which has serious impacts on the stability of ecosystems and the livelihoods of coastal communities. livelihoods of coastal communities. This research aims to examine community-based solutions in restoring degraded aquatic ecosystems, with a focus on the integration of sustainable aquaculture technologies and aquaponic systems. The methodology used was a comprehensive literature analysis of scientific articles, journals and relevant publications. The research findings show that sustainable fisheries management, habitat restoration, environmental education and awareness, implementation of environmentally education and environmental awareness, the application of environmentally friendly technologies, and the development of supportive policies are the main strategies for sustainable fisheries management. development of supportive policies are key strategies in improve conservation effectiveness. The implications of this research show that a community-based approach is not only effective for the conservation of aquatic biodiversity, but also provides practical guidance for policymakers and non-governmental organizations in designing and implementing community-based policy makers and non-governmental organizations in designing and implementing more holistic and effective ecosystem restoration programs that are more holistic and sustainable.

Evaluating the ecological impact of fisheries management strategies in Georgia, USA: A review on current practices and future directions

Effective fisheries management is crucial for maintaining the ecological balance and sustainability of marine ecosystems. This review paper examines the current fisheries management strategies employed in the state of Georgia, USA, and evaluates their ecological impact. The review synthesizes existing research on the implementation and outcomes of various management approaches, including gear restrictions, catch limits, seasonal closures, and marine protected areas. It analyzes the efficacy of these strategies in conserving target species, mitigating bycatch, and preserving the overall health of coastal and estuarine environments. Furthermore, the paper identifies emerging challenges, such as the impacts of climate change and shifting species distributions, and explores potential future directions for fisheries management in Georgia. The findings of this review aim to inform policymakers, resource managers, and stakeholders about the strengths and limitations of current practices, and provide recommendations for developing more comprehensive and adaptive management frameworks to ensure the long-term ecological resilience of Georgia's marine ecosystems.

Robust fisheries management strategies under deep uncertainty

Fisheries worldwide face uncertain futures as climate change manifests in environmental effects of hitherto unseen strengths. Developing climate-ready management strategies traditionally requires a good mechanistic understanding of stock response to climate change in order to build projection models for testing different exploitation levels. Unfortunately, model-based projections of fish stocks are severely limited by large uncertainties in the recruitment process, as the required stock-recruitment relationship is usually not well represented by data. An alternative is to shift focus to improving the decision-making process, as postulated by the decision-making under deep uncertainty (DMDU) framework. Robust Decision Making (RDM), a key DMDU concept, aims at identifying management decisions that are robust to a vast range of uncertain scenarios. Here we employ RDM to investigate the capability of North Sea cod to support a sustainable and economically viable fishery under future climate change. We projected the stock under 40,000 combinations of exploitation levels, emission scenarios and stock-recruitment parameterizations and found that model uncertainties and exploitation have similar importance for model outcomes. Our study revealed that no management strategy exists that is fully robust to the uncertainty in relation to model parameterization and future climate change. We instead propose a risk assessment that accounts for the trade-offs between stock conservation and profitability under deep uncertainty.

Tracking movements of meagre (Argyrosomus regius) during the spawning season: Preliminary indications of off estuary spawning.

Understanding the spawning behavior of meagre (Argyrosomus regius) is crucial for fisheries management and conservation. Meagre forms large spawning aggregations in estuaries, yet details of its spawning grounds remain elusive. We tagged 41 individuals and monitored their movements throughout several spawning seasons. Detections inside estuaries were limited. Fish detected inside the Tejo estuary during the spawning season performed regular movements toward coastal areas, suggesting potential spawning outside estuaries. Our findings underscore the significance of understanding meagre's migratory patterns for effective fisheries management and conservation strategies, supporting the establishment of spatial and seasonal closures during the spawning season.

Detection Of The Thermal Front Using The Cayula-Cornillon Alghorithm: A Case Study Of The State Fisheries Management Area 713, Indonesia

Thermal fronts are pivotal in shaping the marine ecosystem, influencing the presence and distribution of marine species. This study delves into the fluctuating patterns of thermal fronts in Indonesian waters, specifically focusing on the State Fisheries Management Area of the Republic of Indonesia, known as WPPNRI, 713. We identified the distribution and frequency of thermal fronts across different monsoon seasons. Utilizing the extended Cayula Cornillon Algorithm – Single Image Edge Detection (CCA-SIED), we deploy a precise methodology for detecting these fronts, relying on sea surface temperature (SST) gradients to identify specific periods and regions. Our analysis encompasses extensive satellite data collected from Moderate Resolution Imaging Spectroradiometer (MODIS) level 3. Our findings unveil distinct seasonal variations, with a decrease in thermal fronts during the west monsoon and a surge during the east monsoon. Moreover, we identify regional disparities, with denser thermal fronts observed in the southern and middle regions compared to the northern areas. Furthermore, our study underscores the critical need to integrate oceanographic data with fisheries management strategies to address the impacts of climate variability on marine resources. The observed relationships between thermal fronts, nutrient distribution, and fish migration emphasize the necessity for ongoing, localized monitoring to develop adaptive management solutions. This research marks a significant step in characterizing thermal fronts in WPPNRI 713, laying the groundwork for future investigations into other ecologically significant fronts, including those related to chlorophyll, salinity, and nutrients, thereby enhancing our understanding of marine ecosystem dynamics.Keywords: Cayula Cornillon; Fishing Zone; Marine Ecosystem; Sea Surface Temperature; Thermal Fronts

Vessel Monitoring System (VMS) Technology as a Management Strategy for Longline Tuna Capture Fisheries in Benoa

Benoa Port has fishing vessel activities that are the foundation of Bali's tuna swamp fisheries (longlines). Sustainable tuna capture fisheries will be impossible to attain if the number of infractions in the marine and fisheries sectors continues to rise. The government's efforts to reduce infractions in marine and fisheries are achieved through tightening the oversight system. The Vessel Monitoring System (VMS) surveillance system was created to reduce breaches in the marine and fishery sectors. The goal of this study is to determine the monitoring and suspected indication of violations of longlines using the VMS at the Benoa PSDKP as well as to learn about the capture fisheries management strategy using VMS data on longlines at Benoa Port using an analytic hierarchy process (AHP) approach. This study used a qualitative-quantitative descriptive technique with AHP analysis to determine the value of the management priority scale. Based on the findings of monitoring longlines with web tracks from January to December 2022, the most targeted fishing area was the Indian Ocean High Seas, and the most prominent suspected indication of violation was the inactivity of VMS when the vessel was operating. The main approach for managing capture fisheries utilizing VMS data on longlines in Benoa Port with the AHP analysis is for the government to offer subsidies for installing VMS on all fishing vessels, particularly those under 30 GT.

Insights into ovarian maturation and reproductive traits of the deep-water penaeid shrimp Metapenaeopsis andamanensis (Wood-Mason in Wood-Mason and Alcock, 1891) from southwestern India

The present study delves into the reproductive characteristics of Metapenaeopsis andamanensis, a commercially significant deep-water shrimp collected from Sakthikulangara, off Kollam, India (8°56′60.78″ N/76°32′34.27″ E) during September 2019 to May 2022. Despite its economic importance, the reproductive traits of this species remain elusive. This research comprehensively examines macroscopic and microscopic features associated with gonadal maturity stages, including determination of size at first maturity (CL50), gonadosomatic index, and fecundity of M. andamanensis. Male-to-female sex ratio was noted as 1:1.03 using chi-square analysis. The smallest mature individuals were observed at 12 mm and 16 mm carapace length for males and females, respectively. Macroscopic observation categorized females into five groups based on gonadal coloration, while microscopic examination identified seven stages using histological characteristics. Notably, the absence of cortical crypts in the periphery of oocyte cytoplasm, a characteristic feature of the genus Metapenaeopsis, was observed in this species. Males were classified into two categories based on macroscopic and microscopic observation. The gonadosomatic index ranged from 4.25 to 10.13 for mature female individuals, exhibiting a significant increase until stage IV. Continuous spawning was observed, with a peak in May and November. The size at first maturity for females and males was determined as carapace length (CL) 23.05 mm and 17.53 mm, respectively. The average absolute fecundity was calculated as 53,889 with an average relative fecundity of 9934 oocytes. This investigation contributes valuable insights into the reproductive traits of the deep-water penaeid shrimp M. andamanensis, facilitating the development of effective management strategies for sustainable fisheries.

Spatial and seasonal variations in the growth of the populations of tongue sole fish (Cynoglossus quadrilineatus Bleeker, 1851) along four different stations of Makran coast by using the von Bertalanffy model

BackgroundGrowth is a most important life-history trait that defines the maximum size and age, maturation stage, and mortality of any fish species and is also involved in stock assessment models commonly used in fisheries conservation or management. ObjectivesThe present study focused on assessing the growth patterns and related parameters to the population of tongue sole (Cynoglossus quadrilineatus) along different sites of the Makran coast in temperate regions. MethodologyA total of 987 tongue sole fishes were collected seasonally from four different sites along the Makran coast (Gwadar, Pasni, Ormara, and Sur Bandar). Growth parameters i.e., length-weight relationships, length-frequency distribution, von Bertalanffy (VBGF) growth model, and stock status were analyzed. ResultsThe overall results of the length-weight relationship (LWRs) of this species showed only a significantly positive allometric growth pattern (b < 3.0; p < 0.05) observed during three seasons along the four selected sites of Makran Coast. The estimated von Bertalanffy (VBGF) growth parameters of C. quadrilineatus at four stations were described as; maximum observed length (Lmax) = 31.65 cm, asymptotic length (L∞) = 33.32 cm, size at sexual maturity (Lm) = 17.98 cm, Lopt = 20.55 cm, growth coefficient per year (k) = 0.55 year -1, t0 = 0.04 year -1, f = 2.79, Tmax = 2.80 years, tm = 0.78 year, M = 1.64 per year, topt = 1.30 years. The present study also noted seasonal variations in the length frequency distribution (LFD) data between the four selected sites. ConclusionsThus, our study concluded that the von Bertalanffy growth model (VBGF) is the best-fitted model for analyzing the growth patterns of C. quadrilineatus at different sites and during various seasons along the Makran Coast. This model demonstrated superior predictive ability and effectively described changes in growth patterns or body size across sub-populations of C. quadrilineatus at the four study sites. Thus, our research provides valuable insights into the population dynamics and life history traits of this tongue sole population in the Makran coast. Moreover, as the first study on the growth of this species, our findings offer essential information for informing sustainable exploitation, conservation, and fishery management strategies.

The Prevalence of Marine Lipophilic Phycotoxins Causes Potential Risks in a Tropical Small Island Developing State.

Tropical small island developing states (SIDS), with their geographical isolation and limited resources, heavily rely on the fisheries industry for food and revenue. The presence of marine lipophilic phycotoxins (MLPs) poses risks to their economy and human health. To understand the contamination status and potential risks, the Republic of Kiribati was selected as the representative tropical SIDS and 55 species of 256 coral reef fish encompassing multiple trophic levels and feeding strategies were collected to analyze 17 typical MLPs. Our results showed that the potential risks of ciguatoxins were the highest and approximately 62% of fish species may pose risks for consumers. Biomagnification of ciguatoxins was observed in the food web with a trophic magnification factor of 2.90. Brevetoxin-3, okadaic acid, and dinophysistoxin-1 and -2 were first reported, but the risks posed by okadaic acid and dinophysistoxins were found to be negligible. The correlation analysis revealed that fish body size and trophic position are unreliable metrics to indicate the associated risks and prevent the consumption of contaminated fish. The potential risks of MLPs in Kiribati are of concern, and our findings can serve as valuable inputs for developing food safety policies and fisheries management strategies specific to tropical SIDS contexts.