Local Fish Research Articles

Using social media image to identify threatened elasmobranch species caught by a small-scale fishery in a data-poor area.

Sharing fishing activity via social media attracts millions of views. The data from these shares includes key information for a fisheries database such as the species present in the catches and in many cases the number of specimens caught. Many countries in the Global South do not have official information about basic data on fishing activity, especially small-scale activity. In many of such countries like Brazil, overfishing poses a significant threat to numerous threatened species, including elasmobranchs, due to the frailty of fisheries management and law enforcement. The lack of a national (Brazil) data collection program makes sharing data on social media a potential source of fisheries related information. Hence, this study aimed to verify the potential of social media data to describe artisanal fishing and identify elasmobranch species caught by a small-scale fleet in a data-poor Equatorial Southwest Atlantic region. The identification of elasmobranch species was made based on 250 videos shared by local fishers publicly on social media (Youtube™). Among these, sharks and rays were observed in 19 (8%) and 42 (17%) videos, respectively. A total of 98 specimens were recorded, of which 80% could be identified to a species level. Most of the records comprised the stingrays Hypanus berthalutzae and Hypanus guttatus, while Ginglymostoma cirratum was the most recorded shark. More than half of the elasmobranch species recorded are listed at some level of threat according to the IUCN Red List. According to the Brazilian legislation, at least 20% of the species identified in these videos are considered Endangered (EN) or Critically Endangered (CR). Therefore, fishing activity shared via social media can be considered effective in identifying threatened elasmobranch species, as well as providing data on species occurrence, number of specimens, or rare sightings. It is suggested that fishing activity shared via social media be used in parallel with traditional methods (e.g. on-board data and landing observations) to obtain fisheries information and data about endangered species in data poor areas.

Feasibility of Haruan Snakehead Fish Breeding Units for Recipients of Non-Cash Government Assistance Revitalization of People's Seedling Units (UPR) in Hulu Sungai Tengah District, South Kalimantan Province

Haruan snakehead fish, as one of Indonesia's fisheries germplasm wealth, has an important role as a source of animal protein and buffers the stability of inflation rates in the Kalimantan region. The feasibility factor is expected to make a significant contribution to the development of the local fisheries sector and related government policies at the regional level. The research aims to analyze the feasibility of the local haruan fish hatchery business for recipients of government assistance in the form of revitalizing the People's Hatchery Unit (UPR) in Hulu Sungai Tengah Regency, South Kalimantan Province. Research activities take place in the Mufakat Group, Mahang Baru Village, South Labuan Amas District, Hulu Sungai Tengah Regency - Province South Kalimantan. Sampling was carried out using the proportional sampling method, namely samples were taken deliberately from Haruan snakehead fish cultivators who received grant assistance. The total number of respondents was 1 Cultivator Group. Feasibility of the Haruan snakehead fish hatchery unit for recipients of non-cash government assistance for revitalizing people's hatchery units (UPR) in Hulu Sungai Tengah Regency, South Kalimantan Province Hulu Sungai Tengah, South Kalimantan Province, with different discount rates, the present value (NPV) snakehead fish cultivation business obtained a value of Rp. 189,533,025, which shows that this project can provide financial benefits. The Internal Rate of Return (IRR) value of 56% indicates a fairly high rate of return, exceeding the interest rate generally available on the market. The payback period (PP) is 1.76 years Keywords: Haruan Snakehead Fish, Feasibility, Revitalization, HST

Metabolic rate of two invasive Ponto‐Caspian goby species and their native competitors in the context of global warming

Abstract In connection with the expansion of alien gobies in European waters, a question arises whether this process can be enhanced or inhibited by global warming. The gobies are of Ponto‐Caspian origin, where the climate is warmer than in invaded European areas. Therefore, they are likely to cope physiologically with climate warming better than native species. Our aim was to identify differences in metabolic traits under elevated summer temperature between the invasive gobies and their native counterparts. Using a laboratory respirometer, we compared the effect of elevated summer temperature (25 vs. 17°C) on the metabolic responses of fish in two species pairs consisting of an invasive goby versus its native counterpart from the same ecological guild: the invasive racer goby Babka gymnotrachelus versus native European bullhead Cottus gobio, and the invasive monkey goby Neogobius fluviatilis versus native gudgeon Gobio gobio. The paired species share functional traits, including morphological characteristics, despite belonging to different fish families. After 4 weeks of acclimation, standard metabolic rate (SMR), maximum metabolic rate (MMR) and aerobic scope (AS = MMR–SMR) of the fish were determined. We found that SMR increased under elevated temperature irrespective of species, yet it was always lower in the gobies than in natives. The MMR of the racer goby was lower than that of the bullhead across all temperatures, whereas no differences in MMR were found between the gudgeon and monkey goby. On the one hand, the elevated temperature did not affect the AS of the racer goby and bullhead. However, the AS of the racer goby was consistently lower than that of the bullhead across all temperatures. On the other, elevated temperature caused a decrease in AS in both the monkey goby and gudgeon. However, this temperature‐induced change in AS was higher in the gudgeon than in the monkey goby. In terms of AS, the invaders did not always outperform the natives at higher temperatures. However, the invaders had lower living costs by maintaining a lower SMR. These results suggest that invasion by gobies may be facilitated by global warming, which is likely to increase their occurrence and effect on local fish communities in freshwater temperate systems.

The complementary relationship between illegal fishing and maritime piracy: A case study of the Gulf of Guinea

This research paper investigates the interrelationship between maritime crime, specifically sea piracy, and illegal fishing. Existing studies primarily focus on the link between piracy and illegal fishing activities carried out by foreign trawlers, drawing evidence from Somali piracy cases. A causal narrative in past works highlights the detrimental effects of foreign trawlers on local marine resources, ecosystems, and livelihoods, thereby driving local fishers to turn toward piracy and prompting coastal states to address the key issue of illegal fishing by foreign vessels.However, this emphasis on external perpetrators can lead states to pay less attention to local actors involved in illegal fishing and maritime piracy. Therefore, this study redirects our attention to local perpetrators who engage in illegal fishing and maritime piracy. It explores the complementary relationship between these two types of crimes. Our findings indicate that reducing illegal fishing activities in a local area enhances the likelihood of maritime piracy occurrence. By shedding light on the complementarity between illegal fishing and maritime piracy, this research provides valuable insights for policymakers and law enforcement agencies involved in combating maritime crime. It underscores the importance of locally addressing illegal fishing and piracy using a more holistic approach.

Repurposing oil and gas infrastructure as artificial reefs – a global perspective

More than 7000 offshore oil and gas (O&G) installations are found across 53 countries throughout the world’s oceans. During their life span, these structures provide a habitat for marine life and can support diverse assemblages. At the end of planned service life, they are decommissioned which usually involves the complete removal of infrastructure from the ocean, resulting in the loss of these marine communities. Various countries have repurposed O&G platforms as artificial reefs as an alternative solution to decommissioning, such as the Rigs-to-Reefs (R2R) program developed by the United States (US). The repurposing of O&G platforms may have benefits in preserving or enhancing ecological communities, as well as reducing the impacts and costs associated with removal and disposal onshore. The placement of O&G platforms in the ocean as artificial reefs demands prudent planning and high-level management to ensure the anticipated benefits are delivered and potential impacts are managed. The US National Artificial Reef Program (NARP) along with the R2R program provides guidelines on various aspects of artificial reef use, including planning, site selection, design and management. Since 1980, the US has successfully converted more than 593 O&G platforms to permanent artificial reefs due to the active participation and support of O&G operators, government, local fishing and diving communities. Other countries are also taking initiatives to repurpose their O&G infrastructure. The aim of this paper is to identify key considerations in the repurposing of O&G infrastructure as artificial reefs, using the US R2R program and other geographies as examples.

Rare and unexplored traditional waste food processing and fermentation methods of the meitei-pangal community of Manipur: A northeastern state of India

This research examines rare and unexplored traditional waste food processing and fermentation methods. Processed waste foods as well as fermented foods represent an important segment of the most commonly consumed foodstuffs and the nutrient suppliers of the living populations across the world. Soibum, hawaijar, ngari, hentak, and yongchak are some of the most commonly consumed processed waste foods and fermented foods among the natives of Manipur. To our knowledge, no proper compilation of traditional methods of waste food processing and the fermentation processes of the meitei-pangal community of Manipur has been carried out yet. In this study, the traditional methods of processing waste foods and fermentation steps of foodstuffs commonly consumed by the Meitei pangal community of Manipur are surveyed and recorded for the first time. The results of the study reveal that six unique and diverse categories and ways of processing waste foods and the fermentation of food products locally known as Yongchak, chakring, ngari, hentak, soibum, and hawaijar were practiced by every family of the meitei-pangal community of Manipur using local stinky beans (Parkia sp.), cooked rice-based products, local fish (Puntius sp.), bamboo shoots (Bambusa sp.), and soybean products. The study will offer a new understanding of the waste food processing and fermentation processes of some of the most commonly consumed foodstuffs by the natives of the northeastern states of India, with numerous health advantages for prospective future drug discoveries and nutraceutical applications.

A comparative study on the treatment of kitchen grey water using microalgae consortia and microalgae-synthesized silver nanoparticles.

Comparative study on the potential of microalgae consortia and green-synthesized silver nanoparticles using microalgae (M-AgNP) consortia for the treatment of kitchen grey water was investigated in this study. The microalgae consortia consisting of four species, viz., Chlorella sp., Scenedesmus sp., Coelastrum sp., and Pediastrum sp. were isolated from a local fish pond and the silver nanoparticles were synthesized with the same. Thus, synthesized silver nanoparticles exhibited a distinctive yellowish-brown colour and spherical morphology. Extensive qualitative and quantitative characterization techniques were employed to determine their size and morphology. Both microalgae consortia and M-AgNP were used separately for the treatment of kitchen grey water under experimental conditions. The synthesized silver nanoparticles demonstrated promising potential for domestic wastewater treatment, leading to substantial reductions in various parameters: total dissolved solids (29.6%), conductivity (49.4%), chemical oxygen demand (64.6%), and heavy metals (arsenic-63.5%, zinc-45.6%, cadmium-88%, copper-60.52%, and lead-80.82%). Notably, microalgae exhibited superior removal efficiency for nitrate (83.1%), sulphate (70.3%), and phosphate (96.5%) compared to microalgae-synthesized silver nanoparticles. This study underscores the effective utilization of both microalgae and microalgae-synthesized silver nanoparticles for wastewater treatment applications.

Diet choices determine mercury exposure risks for people living in gold mining regions of Peru

Artisanal and small-scale gold mining (ASGM) is the largest global anthropogenic mercury (Hg) source and is widespread in the Peruvian Amazon. Consuming Hg-laden foods exposes people to this potent neurotoxin. While numerous studies have examined fish Hg content near ASGM, Hg accumulation in other commonly consumed animal-and plant-based foods from terrestrial environments is often overlooked. In this study, we aim to address understudied dietary Hg exposures.To understand Hg exposure from food staples in the Peruvian Amazon, we measured total and methyl Hg in local crops, fish, chicken meat, chicken feathers, and eggs from ASGM-impacted and upstream (reference) communities. Diet surveys were used to estimate probable weekly Hg intake from each food. Fish and chicken stable carbon and nitrogen isotope signatures were analyzed to evaluate trophic magnification.Though few crops exceeded food safety recommendations, rice methyl Hg proportions were high (84%). Trophic level was an expected key predictor of fish Hg content. 81% (17 of 21) of local carnivorous fish exceeded WHO and EPA recommendations. Compared to upstream communities, mining-impacted communities demonstrated elevated total Hg in crops (1.55 (interquartile ranges (IQR): 0.60–3.03) μg kg−1 upstream versus 3.38 (IQR: 1.62–11.58) in mining areas), chicken meats (2.69 (IQR: BDL–9.96) μg kg−1 versus 19.68 (IQR: 6.33–48.1)), and feathers (91.20 (IQR: 39.19–216.13) μg kg−1 versus 329.99 (IQR: 173.22–464.99)). Chicken meats from mining areas exhibited over double the methyl Hg concentrations of those upstream. Methyl Hg fractions in chicken muscle tissue averaged 93%. Egg whites and livers exceeded Hg recommendations most frequently. Proximity to mining, but not trophic position, was a predictor of chicken Hg content.Our results demonstrate that terrestrial and aquatic foods can accumulate Hg from mining activity, introducing additional human Hg exposure routes. However, locally sourced carnivorous fish was the largest contributor to an estimated three-fold exceedance of the provisional tolerable weekly Hg intake.

Puzzling parrotfishes: Radiocarbon age validation and updated longevity estimates for western Atlantic species in support of sustainable fisheries management

For management efforts to succeed in Caribbean fisheries, local fishers must support and be willing to comply with fishing regulations. This is more likely when fishers are included in a stock assessment process that utilizes robust scientific evidence, collected in collaboration with fishers, to evaluate the health of fish stocks. Caribbean parrotfishes are important contributors to coral reef ecosystem health while also contributing to local fisheries. Scientifically robust stock assessments require regional species-specific information on age-based key life history parameters, derived from fish age estimates. Evaluation of the accuracy of age estimation methods for fish species is a critical initial step in managing species for long-term sustainable harvest. The current study resulted from a collaborative research program between fish biologists and local fishers investigating age, growth, and reproductive biology of the seven parrotfish species landed in U.S. Caribbean fisheries; specifically, we validated age estimation for stoplight parrotfish Sparisoma viride and queen parrotfish Scarus vetula. This is the first study to directly validate age estimation for any parrotfish species through analysis of Δ14C from eye lens cores. Our age estimation validation results show that enumeration of opaque zones from thin sections of sagittal otoliths for a Sparisoma and a Scarus species provides accurate age estimates. The oldest stoplight parrotfish and queen parrotfish in the Δ14C age estimation validation series were 14 y and 16 y; while the oldest stoplight parrotfish and queen parrotfish we aged to-date using the Δ14C validated age estimation method were 20 y and 21 y, respectively. Fish longevity (maximum age attained/life span) is a key life history parameter used for estimation of natural mortality, survivorship, and lifetime reproductive output. Past reviews on parrotfishes from the Pacific and Atlantic concluded that most Caribbean/western Atlantic parrotfish species are relatively short-lived with estimated maximum ages ranging from 3–9 y. However, information from our collaborative research in the U.S. Caribbean combined with recently published age estimates for Brazilian parrotfish species indicate that many western Atlantic parrotfishes are relatively long-lived with several species attaining maximum ages in excess of 20 y.

Increase in the Abundance of Invasive Fish Species in the Ciliwung River, DKI Jakarta and West Java Provinces

The Ciliwung River is one of the important rivers in the Jakarta Special Capital Region (DKI Jakarta) and West Java. The existence of local fish in the Ciliwung River is threatened by the presence of invasive fish. This research aims to identify the types of invasive fish along the Ciliwung River from 2023 to 2024 and compare them with previous research in 2011. The study uses 6 segments according to Minister of Environment and Forestry Decree No. SK.298/Menlhk/Setjen/PKL.1/6/2017. Each segment consists of 3 research plots, totaling 18 research stations. The sampling method involves collecting fish using environmentally friendly fishing gear. The research results show the presence of 10 species from 5 families and 4 non-native fish orders that are invasive. The most abundant invasive fish species in the Ciliwung River are, in order, Plecostomus (Pterygoplichthys pardalis), Mosquito Fish (Gambusia affinis), Guppy (Poecilia reticulata), Platy (Xiphophorus helleri), Nile Tilapia (Oreochromis niloticus), Bristlenose Pleco (Ancistrus temminckii), Glossom (Andinoacara rivulatus), Carp (Cyprinus carpio), Red Devil (Amphilophus labiatus), and African Catfish (Clarias gariepinus). There has been a 100% increase in the number of invasive fish species in the Ciliwung River compared to the 2011 study, which identified only 5 invasive fish species.

DETERMINATION OF FISH DIVERSITY IN THE ROCKY HABITAT AROUND MERSIN BOĞSAK ISLAND (NORTHEAST MEDITERRANEAN) BY VISUAL CENSUS METHOD

This study was conducted in the rocky habitat of Boğsak Island in Mersin Bay in November, March and July, representing the fall, spring and summer months of 2022-2023, by scuba diving between 0-18 m depth for approximately 40 hours. The Go-Pro Hero 12 black camera was used in the study. In the study, the structure of the fish community of the rocky bottom habitat of Boğsak Island in Mersin Bay was determined, and the seasonal availability, abundance, feeding status, and distribution of local and non-native fish species were determined. Sampling was carried out using the underwater visual counting method, and surveys were made along a linear line. Shannon-Weiner Diversity Index (H'), Homogeneity and Relative Diversity Index Evennes (J) and Species Richness Index Margalef Rhichnes (D) were used to determine the species diversity. The distance of the relationship between the data was determined with N-MDS, one of the multidimensional scaling analyses. The Euclidean formula was used to determine the distances of coordinates in the scaling. Principal component analysis was used to classify species based on the number of individuals. A total of 29 fish species, including 28 bony fish species belonging to 15 families and 1 cartilaginous Gymnura altavela (Linnaeus, 1758), were identified in the study area. The richest family in terms of species diversity was Sparidae (6), followed by Mullidae (3), Serranidae (3), Tetraodontidae (2), Soleidae (2), Labridae (2) and other families with 1 species each. Of the fish species identified throughout the year in the study area, 52% were Atlantic, 37% were Indo-Pacific and 11% were cosmopolitan. It was found that 41% of the fish species were invertivores, 22% carnivores (feeding on fish and invertebrates), 18% omnivores, 11% planktivores, 4% herbivores and 4% piscivores. Torquigener flavimaculosus in summer, Cheilodipterus novemstriatus in spring, and Chromis chromis in fall were the most abundant species. According to the Shannon diversity index (H'), the highest species diversity was found in the fall (H'=2,956), followed by spring (H'=2,501) and summer (H'=2,458). Homogeneity and relative diversity index Evennes (J) was determined as J=0.642 in spring, J=0.531 in summer and J=0.800 in fall. The species richness index Margalef Rhichnes (D) was highest in autumn (d=4.804), then in summer (d=3.917) and lowest in spring (d=3.632). This is the first study to investigate the structure of rocky habitat fish communities in the northeastern Mediterranean, which shows a dynamic structure in terms of biodiversity, and is expected to contribute to researchers working in this field.

Defining the role of Sabellaria alveolata reefs as nursery areas for juvenile fish: first evidence from drone-based imagery and underwater visual census data

The biogenic reefs built by the honeycomb worm Sabellaria alveolata constitute priority habitats along Atlanto-Mediterranean coastal areas. Despite their wide extent and important ecological role, the nursery value of S. alveolata reefs remains unclear, and more information is needed to define how such structured habitats affect juvenile fish assemblages. In this study, habitat use by juveniles of 7 fish species was investigated by underwater visual census (UVC) at 3 study sites representing a gradient of complexity of Sabellaria reef habitats, spanning from a large and uniform reef to patchy and isolated small reef formations. Sabellaria reef metrics derived by drone-based cartography and GIS analysis were used to quantitatively monitor the seasonal structural changes occurring due to the natural dynamics of the reefs. We also tested the potential effect of Sabellaria habitats on the growth and relative condition factor (Kn) of white seabream Diplodus sargus juveniles. Five of the 7 surveyed species, especially sparid fishes, showed a clear preferential association with Sabellaria formations. Generalized additive modelling revealed a significant effect of the compactness ratio on estimated fish densities at high and low index values. The juvenile fish sampled on Sabellaria reefs exhibited higher values of Kn than those sampled on rocky habitats, supporting the hypothesis that structural complexity positively affected their condition. We provide evidence on habitat use by juveniles, suggesting that the presence of the Sabellaria reef may act as a nursery and affect local fish density in Mediterranean coastal waters.

Mapping the occurrence of Eustrongylides spp. in fish species caught from six lakes in Central Italy (Tuscany and Latium regions): Implications for local fishery supply chains

In the present study, in order to expand the knowledge on the distribution of parasites of the genus Eustrongylides in never investigated Italian lacustrine areas of Tuscany and Latium, fish specimens from four Tuscan lakes (Bilancino, Chiusi, Montedoglio and San Cipriano) and two Latium lakes (Bolsena and Bracciano) were collected and analyzed. The parasitological analysis, consisting of a visual inspection followed by a chloro-peptic digestion, was performed on 1650 specimens belonging to 17 species: European perch (Perca fluviatilis), Pumpkinseed (Lepomis gibbosus), Pike-perch (Sander lucioperca), Largemouth black bass (Micropterus salmoides), Pike (Esox lucius), Big-scale sand smelt (Atherina boyeri), Tench (Tinca), European Whitefish (Coregonus lavaretus), Channel catfish (Ictalurus punctatus), Chub (Squalius cephalus), Rudd (Scardinius erythrophthalmus), Common bleak (Alburnus alborella), South European roach (Sarmarutilus rubilio), South European nase (Protochondrostoma genei), Italian riffle dace (Telestes muticellus), Goldfish (Carassius auratus), and Freshwater bream (Abramis brama). Eustrongylides spp. larvae were only found in one specimen of European perch caught in Bracciano Lake and purchased from a local fishmonger (P = 3.3%; MI = 1; MA = 0.03). The only isolated Eustrongylides spp. larva was submitted to molecular analysis of the ITS gene region and identified as E. excisus. This finding adds Bracciano Lake to the list of the several Italian lakes in which nematodes belonging to this genus have been reported. Even if the observed prevalence is currently low, the presence of the parasite in this local freshwater fish supply chain requires FBOs to adopt risk management measures to prevent contaminated products from reaching final consumer. Moreover, future investigations will show if the parasite expands in these areas.

Assessing the impacts of aquaculture on local fish communities using environmental DNA metabarcoding analysis

AbstractFish aquaculture potentially affects the local ecosystem through feed (leftovers) and feces. However, evaluation of its impacts on biodiversity, especially those of mobile organisms such as fish, is not straightforward. Here, we report a case study in which environmental DNA (eDNA) metabarcoding with MiFish universal primers for the 12S rRNA region of fish is used to detect and assess the impact of aquaculture on local fish communities. In Shizugawa Bay, Minamisanriku Town, Miyagi Prefecture, Japan, Oncorhynchus kisutch (coho salmon) is aquacultured in sea cages from November to July, but is absent from August to October. We conducted eDNA surveys in June, August, October, and December 2021 of water at depths of 5 m and 1 m above the bottom obtained from two sites, one approximately 100 m and the other approximately 2500 m from the nearest aquaculture site. The total number of operational taxonomic units (OTUs) detected was 122, with a maximum of 50 and a minimum of 10. With distance‐based redundancy analysis (dbRDA) and PERMANOVA applied to the eDNA‐based community compositional data, we detected a significant effect of the presence of O. kisutch aquaculture on fish biodiversity. The generalized linear model (GLM) applied to each detected OTUs indicated that the aquaculture was associated positively with Leucopsarion petersii (ice goby), and Oncorhynchus spp. and negatively with Chaenogobius annularis (forktongue goby). Environmental DNA metabarcoding surveys, combined with multivariate statics, are a promising tool to identify the dimension of biodiversity that human activity affects and would serve as a basic survey for sustainable use of the sea.

Application of environmental DNA metabarcoding to identify fish community characteristics in subtropical river systems

AbstractFish are vital in river ecosystems; however, traditional investigations of fish usually cause ecological damage. Extracting DNA from aquatic environments and identifying DNA sequences offer an alternative, noninvasive approach for detecting fish species. In this study, the effects of environmental DNA (eDNA), coupled with PCR and next‐generation sequencing, and electrofishing for identifying fish community composition and diversity were compared. In three subtropical rivers of southern China, fish specimens and eDNA in water were collected along the longitudinal (upstream–downstream) gradient of the rivers. Both fish population parameters, including species abundance and biomass, and eDNA OTU richness grouped 38 sampling sites into eight spatial zones with significant differences in local fish community composition. Compared with order‐/family‐level grouping, genus‐/species‐level grouping could more accurately reveal the differences between upstream zones I−III, midstream zones IV−V, and downstream zones VI–VIII. From the headwaters to the estuary, two environmental gradients significantly influenced the longitudinal distribution of the fish species, including the first gradient composed of habitat and physical water parameters and the second gradient composed of chemical water parameters. The high regression coefficient of alpha diversity between eDNA and electrofishing methods as well as the accurate identification of dominant, alien, and biomarker species in each spatial zone indicated that eDNA could characterize fish community attributes at a level similar to that of traditional approaches. Overall, our results demonstrated that eDNA metabarcoding can be used as an effective tool for revealing fish composition and diversity, which is important for using the eDNA technique in aquatic field monitoring.

Introduksi Teknologi DNA Barcoding kepada Staf UPTD Perikanan Budidaya Air Payau dan Laut Karang Intan

Partners in community service activity are UPTD Brackish and Marine Aquaculture, Karang Intan, one of the centers under South Kalimantan Province that specializes in the hatchery of local fish such as snakehead (Channa striata), common carp (Cyprinus carpio), and climbing perch (Anabas testudineus). The problem in the partner is fish farming that still relies on seeds from nature, which causes several problems, such as slow seed growth, decreased production quality, disease attacks and hereditary abnormalities that are getting higher due to interbreeding. Based on these problems, the team collaborated with the UPTD for Brackish and Marine Aquaculture, Karang Intan, to improve the genetic quality of fish by introducing DNA barcoding techniques, especially at the spawning stage. The introduction of DNA barcoding technology is carried out through (1) classical counseling and group discussions, 2) training and assistance covering technical aspects of DNA barcoding (fish DNA isolation, DNA amplification, visualization of PCR products with electrophoresis, to the sequencing). Based on the evaluation, 100% of the participants were enthusiastic and realized the importance of DNA barcoding techniques to produce superior broodstock and fish fry, especially for snakehead, common carp, and climbing perch commodities.

Setting PFAS-Based Fish Consumption Advisories for Virginia Waterways

This policy memo is intended for the Commissioner of Health at the Virginia Department of Health (VDH). The memo provides recommendations when assessing the need for per- and polyfluoroalkyl substances (PFAS)-based fish consumption advisories in Virginia waterways. High-frequency fish consumers and sensitive populations face a greater risk of negative health effects from exposure to PFAS through eating local freshwater fishes. By performing state-wide fish screening assessments for relevant PFAS, the VDH can determine if the nutritional benefits from eating fish outweigh the health risks from PFAS exposure. The following memo recommends that VDH update their PFAS fish tissue screening assessment to include PFUnA and PFDA and release final fish tissue screening recommendations for PFOA and PFOS.

Production performance of Seurukan fish (Osteochilus sp.) with high density in recirculating system

One of the local fish (native species) that is popular with the public and has quite good market prospects in Aceh is the seurukan fish (Osteochilus sp.). Seurukan fish cultivation technology with a recirculation system needs to be developed so that its potential can be utilized optimally. This research aims to evaluate production performance and determine the optimal stocking density for rearing seurukan fish (Osteochilus sp.) in a recirculation system. This research was conducted by experimental method. The experimental design used was a completely randomized design (CRD) with three treatments of stocking density and each treatment was repeated four times. The treatments are P1 (5 fish/m2), P2 (10 fish/m2), and P3 (15 fish/m2). The rearing period for Seurukan fish lasts for 50 days. The parameters tested during the research included biological parameters consisting of survival, absolute growth rate, feed conversion ratio, weight diversity coefficient, and water quality parameters including temperature, pH and dissolved oxygen. The results showed that the seurukan fish reared at different stocking densities using a recirculation system had a significant effect on the absolute growth rate and the coefficient of variation in weight. The best treatment in this study was 5 fish/m2, with a survival rate of 100%, an absolute growth rate of 0.04 g/head/day, a feed conversion ratio of 1.63, and a coefficient of variation of weight of 17.99%.Key words: production performance; seurukan fish; recirculation system; stocking density

Growth And Food Habits Of Pelian Fish Tor Douronensis Caught Using Tuba Root Poison In Krayan Nunukan, North Kalimantan

The use of semah fish with the local name pelian fish in nature is carried out using various methods, one of which is using tuba root plant poison. This tuba root poison is thought to have an impact on the biological condition of pelian fish and aquatic ecology. In connection with this, this research aims to analyze the size distribution, growth type and food habits of pelian fish. The research was conducted from June to August 2023 in West Krayan District, Nunukan Regency, North Kalimantan. The results of the study showed that the length distribution of pelian fish caught using tuba root plant poison was 30.626 ± 7.048 cm, with a weight of 786.531 ± 430.066 g. The growth pattern is negative allometric with eating habits consisting of moss at 44.57%, insects at 33.04%, pieces of fruit at 10.00% and unidentified at 12.39%. Moss and insects are the main food, while fruit is a complementary food. Based on the results obtained, pelian fish in nature can be caught using moss bait. The use of high doses of tuba root can cause damage to the fish's gills, which can cause fish death as a result of not being able to neutralize rotenone.

Lionfish (Pterois miles) in the Mediterranean Sea: a review of the available knowledge with an update on the invasion front

Invasive species often severely impact ecosystems and human activities in the areas that they invade. The lionfishes Pterois miles and P. volitans are regarded as the most successful invasive fishes in marine ecosystems. In the last 40 years, these Indo-Pacific predators have established in the tropical western Atlantic Ocean, with well-documented detrimental effects on the local fish communities. Around 10 years ago, a second invasion began in the Mediterranean Sea, which is being colonised by P. miles. Given the invasive potential of P. miles and the fact that the ecology and biodiversity of the temperate/sub-tropical Mediterranean Sea offer a different setting from the tropical western Atlantic, specific knowledge on this second invasion is needed. Here, we: (i) review the scientific knowledge available on the ecology of invasive lionfishes, (ii) discuss such knowledge in the context of invasion ecology and (iii) suggest future research avenues on the P. miles invasion in the Mediterranean Sea. In addition, we offer an update on the spread of P. miles in the Mediterranean Sea. While the history and development of the Mediterranean invasion are resolved and some mitigation plans have been implemented locally, the study of the interactions of P. miles with Mediterranean species and their impact on the local biodiversity is in its infancy. Closing this gap will lead to important fundamental insights in invasion ecology and will result in predictions on the impact of P. miles on the ecology and ecosystem services of the Mediterranean Sea. Such information will have practical implications for policy-makers aiming to devise sound and efficient mitigation plans.