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Fish farms are occasionally built on delicate natural habitats, which can have severe environmental effects. Many industrial fishing methods also devastate aquatic habitats with the addition of overfishing practices. While environmentalists and academics have been concerned about the rapid extinction of fishery resources, the existing evidence is still inconclusive. This study examined whether catching overfishing could explain the environmental Kuznets curve (EKC) hypothesis among Organisation for Economic Cooperation and Development (OECD) countries. The study used four empirical strategies, which are framed in the panel time series analysis. (a) it assessed the prior behaviour of the variables based on second-generation panel unit roots tests using Cross-sectional ADF(CADF) and Cross-sectional IPS. (b) it also assessed the potential long-run relationship among the variables using the Westerlund Panel Cointegration test. (c) it explores the fishery Kuznets curve for OECD countries using Cross-sectional Dependency - Autoregressive Distributed Lag (CS-ARDL) and Augmented Mean Group (AMG) methodology. (d) it also examines the short direction of causality among the variables using the Dumitrescu--Hurlin Panel Granger Causality test, which is built on standardised panel statistics suitable for small sample properties, even in the presence of cross-sectional dependency. Five main findings can be deduced from our analysis. Firstly, the preliminary check confirms are only stationary only after the first difference. Secondly, the analysis also suggests that there is a long-run relationship among the variables. Thirdly, the findings showed that fish exploration has a negative effect on carbon emissions. Fourthly, the quadratic term of economic growth unidirectionally Granger causes CO2 emissions. Fifthly, we found evidence in support of the EKC hypothesis across OECD countries. Finally, our results highlighted the importance of fishery control in promoting environmental quality among OECD countries. We recommend reform in public policy that encourages sustainable fishing along with innovative research into modern fishing methods that reduces emissions. A better method of fishing can be developed with the support of cutting-edge research, which can also help reduce water pollution and the threat that overfishing poses to biodiversity. JEL classifications: Q12; Q15; Q54 Keywords: Fishery, Kuznets Curve, time Series; environment, OECD countries Contact author's email address: olatunji.shobande1@abdn.ac.uk, INTRODUCTION The role of fishing activities in carbon emissions has long been a concern among academia and environmental experts. Fishing is not only an important source of food for the [...]

Fish farms are occasionally built on delicate natural habitats, which can have severe environmental effects. Many industrial fishing methods also devastate aquatic habitats with the addition of overfishing practices. While environmentalists and academics have been concerned about the rapid extinction of fishery resources, the existing evidence is still inconclusive. This study examined whether catching overfishing could explain the environmental Kuznets curve (EKC) hypothesis among Organisation for Economic Cooperation and Development (OECD) countries. The study used four empirical strategies, which are framed in the panel time series analysis. (a) it assessed the prior behaviour of the variables based on second-generation panel unit roots tests using Cross-sectional ADF(CADF) and Cross-sectional IPS. (b) it also assessed the potential long-run relationship among the variables using the Westerlund Panel Cointegration test. (c) it explores the fishery Kuznets curve for OECD countries using Cross-sectional Dependency - Autoregressive Distributed Lag (CS-ARDL) and Augmented Mean Group (AMG) methodology. (d) it also examines the short direction of causality among the variables using the Dumitrescu--Hurlin Panel Granger Causality test, which is built on standardised panel statistics suitable for small sample properties, even in the presence of cross-sectional dependency. Five main findings can be deduced from our analysis. Firstly, the preliminary check confirms are only stationary only after the first difference. Secondly, the analysis also suggests that there is a long-run relationship among the variables. Thirdly, the findings showed that fish exploration has a negative effect on carbon emissions. Fourthly, the quadratic term of economic growth unidirectionally Granger causes CO2 emissions. Fifthly, we found evidence in support of the EKC hypothesis across OECD countries. Finally, our results highlighted the importance of fishery control in promoting environmental quality among OECD countries. We recommend reform in public policy that encourages sustainable fishing along with innovative research into modern fishing methods that reduces emissions. A better method of fishing can be developed with the support of cutting-edge research, which can also help reduce water pollution and the threat that overfishing poses to biodiversity. JEL classifications: Q12; Q15; Q54 Keywords: Fishery, Kuznets Curve, time Series; environment, OECD countries, INTRODUCTION The role of fishing activities in carbon emissions has long been a concern among academia and environmental experts. Fishing is not only an important source of food for the [...]

Oysters are farmed worldwide and one of the main problems is infestation by polydorin polychaetes. The native Crassostrea gasar and the exotic Pacific Crassostrea gigas oysters support aquaculture production along the subtropical southern Brazilian coast. Worm infestation rates in the two oyster species were evaluated, hypothesizing that infestation is related to stocking densities and hydrodynamic intensity. The main oyster production areas in Brazil were sampled: Parana state, Medeiros (25[degrees] 22' S, 48[degrees] 27' W), Ponta Oeste da Ilha do Mel (25[degrees] 29' S, 48[degrees] 22' W), and Cabaraquara (25[degrees] 49' S, 48[degrees] 34' W) and the Santa Catarina state, Riberao da Ilha (27[degrees] 43' S, 48[degrees] 33' W). Generalized linear models were performed to analyze the effects of sites characterized by different stocking density, hydrodynamic intensity and mean sea surface temperature (SST), the condition index, and the oyster species (native or exotic). Polydorin infestation was higher (mean of 6.02 polydorins/oyster) under higher oyster stocking densities and intermediate hydrodynamic intensity sites (Riberao da Ilha, in the Santa Catarina state). In Parana State, the two sites with similar stocking densities, Ponto Oeste (7,638 oysters/[m.sup.2]) and Cabaraquara (7,550 oyster/[m.sup.2]) presented a higher polydorin infestation in the site with low hydrodynamic intensity and higher mean SST (5.34 vs. 2.64 polydorins/oyster, respectively). The condition index was not impacted by the polydorin infestation. Native C. gasar showed a higher polydorin infestation than the exotic C. gigas (6.02 vs. 1.36, respectively), indicating a higher vulnerability to worm infestation. These results may lead to a better understanding of the infestation patterns of locally grown oysters and to the implementation of better farming management. KEY WORDS: spionids, shell-boring, aquaculture, oysters, Brazil, INTRODUCTION Oysters are farmed globally and their commercial production has increased rapidly in recent decades (Wijsman et al. 2019, FAO 2020). Many direct and indirect factors can affect the functioning [...]

Oyster habitat restoration seeks to recover lost ecosystem services including increased provisioning of refuge and foraging habitat for fish and invertebrate communities. The goal of this study was to quantify the ecosystem service benefit of habitat provisioning in Ninigret Pond, RI, following oyster restoration. Four metrics were measured, abundance, biomass, species richness, and diversity, as well as isotopic composition in fish and invertebrates collected seasonally from restored oyster, aquaculture, and bare sediment sites, to examine whether the oyster habitat outperformed the bare sediment habitat. Sampling locations were chosen in Foster's Cove north and south. Grassy Point, South Sanctuary, and an Aquaculture lease; each had two restored oyster sites and one bare sediment site. Each site was sampled using a box trap, seine net, shrimp trap, and minnow trap. Oyster habitats had significantly greater metrics than did bare sediment habitats in some comparisons from the box trap and seine net samples. Restored oyster sites at South Sanctuary had lower metric values than the other oyster sites. Metrics from the Aquaculture sites were comparable to the Foster's Cove and Grassy Point restored oyster sites and often outperformed South Sanctuaryrestored oyster sites. Seasonally, spring and autumn samples tended to have higher abundance and biomass values than summer samples. Isotopic composition of five species occurring at both restored oyster and bare sediment sites demonstrated some differences in the trophic levels between species but not between habitat types. In Ninigret Pond, fish and invertebrate abundance, biomass, species richness, and diversity benefit from the use of oyster and bare sediment habitats. Coastal zone managers interested in restoring the ecological function of oyster reefs to support fish and invertebrate communities should consider strategically locating restoration projects within the mosaic of structured habitats and monitoring them for selected ecosystem services. KEY WORDS: nekton, habitat preference, oyster reef, aquaculture, restoration, INTRODUCTION During the past century, degradation of habitats and the ecosystem services they provide in coastal and marine environments has resulted from multiple stressors including nutrient pollution, overexploitation of resources, [...]

Warming waters are changing marine pathogen dispersal patterns and infectivity worldwide. Coupled biological--physical modelling has been used in many systems to determine the connectivity of metapopulations via infectious disease particles. Here we model the connectivity of sea lice larvae (Lepeophtheirus salmonis) among salmon farms in the Broughton Archipelago, British Columbia, Canada, using a coupled biological-physical model. The physical model simulated pathogen dispersal, while the biological component influenced the survival and developmental rates of the sea lice. Model results predicted high temporal variability in connectivity strength among farms, an emergent effect from the interacting parts of the simulation (dispersion versus survival and development). Drivers of temporal variability were disentangled using generalized additive modeling, which revealed the variability was most strongly impacted by the spring freshet, which can act as a natural aid for sea lice control in the Broughton Archipelago. Our results suggest that farm management strategies can benefit by accounting for short-term spikes in regional pathogen connectivity among farms. Additionally, future scenarios of a warming climate with reduced snowpack can make sea lice control more challenging. Le rechauffement des eaux modifie les motifs de dispersion et l'infectiosite des pathogenes marins a l'echelle planetaire. La modelisation couplee biologique-physique a ete utilisee dans de nombreux systemes pour determiner la connectivite de metapopulations par le biais de particules de maladie infectieuse. Nous modelisons la connectivite des larves de pou du poisson (Lepeophtheirus salmonis) entre des fermes salmonicoles de l'archipel Broughton (Colombie-Britannique, Canada), en utilisant un modele couple biologique-physique. Le modele physique simule la dispersion du pathogene, alors que la composante biologique influence les taux de survie et de developpement des poux du poisson. Les resultats du modele predisent une forte variabilite temporelle de la force de la connectivite entre les fermes, un effet emergent decoulant des aspects interdependants de la simulation (dispersion et survie et developpement). Les facteurs de variabilite temporelle sont demeles en utilisant un modele additif generalise, qui revele que la crue printaniere exerce la plus forte influence sur la variabilite et peut servir de mecanisme naturel pour lutter contre les poux du poisson dans l'archipel Broughton. Nos resultats donnent a penser que la prise en compte de pointes de courte duree de la connectivite regionale de pathogenes entre les fermes peut ameliorer les strategies de gestion des fermes. Les scenarios de rechauffement climatique futur et de reduction associee du manteau neigeux pourraient en outre rendre la lutte contre les poux du poisson plus difficile. [Traduit par la Redaction], Introduction Transmission of water-borne pathogens (parasites, viruses, bacteria) in marine environments depends on factors influencing the movement and viability of the pathogen. Passive dispersal depends on local hydrodynamics, as dictated [...]

The global expansion of aquaculture is a constant propagule pressure that enables the establishment of exotic species in freshwater and marine environments. Here, we provide the first report on the presence of exotic coho salmon (Oncorhynchus kisutch) at the extreme south of Patagonia, in the island of Tierra del Fuego (TDF). During the last 6 years, 43 juvenile coho salmon were captured along the Beagle Channel, while one adult was captured in fresh water. Scale analysis showed that migration from fresh water as smolt would occur during their first winter of life. Mitochondrial DNA analyses revealed two haplotypes previously reported in North America and a new haplotype not reported before. We developed an environmental DNA assay for detecting coho salmon DNA from fresh water, obtaining positive results in three rivers. Additionally, one of these rivers was monitored monthly for a year, and we detected coho salmon DNA over 7 months, revealing the probable occurrence of coho salmon juveniles in fresh water. These results suggest the potential establishment of self-sustaining populations of coho salmon in TDF. L'expansion de l'aquaculture a l'echelle planetaire est une pression propagulaire constante qui rend possible l'etablissement d'especes exotiques dans les milieux marins et d'eau douce. Nous presentons le premier signalement de la presence de saumons cohos (Oncorhynchus kisutch) exotiques a l'extreme sud de la Patagonie, dans l'lle de la Terre de Feu (TDF). Au cours des 6 dernieres annees, 43 saumons cohos juveniles ont ete captures le long du canal du Beagle, alors qu'un adulte a ete capture en eau douce. L'analyse d'echelle montre que la migration des saumoneaux a partir de milieux d'eau douce se produirait durant le premier hiver de leur vie. Des analyses d'ADN mitochondrial revelent deux haplotypes deja signales en Amerique du Nord et un nouvel haplotype jamais signale auparavant. Nous presentons une methode d'analyse de l'ADN environnemental mise au point pour deceler la presence d'ADN de saumons cohos dans l'eau douce, qui donne des resultats positifs pour trois rivieres. Une de ces trois rivieres a en outre fait l'objet d'un suivi mensuel pendant un an qui a permis de detecter de l'ADN de saumon coho pendant sept mois, revelant ainsi la presence probable de saumons cohos juveniles en eau douce. Ces resultats sembleraient indiquerun possible etablissement de populations autosuffisantes de saumons cohos en TDF., Introduction Freshwater environments of Tierra del Fuego Island (TDF) have the lowest native fish biodiversity of all Patagonia (Cussac et al. 2009), being inhabited only by five species: peladilla (Aplochiton [...]

Byline: H. Naz, S. Abdullah, T. Ahmed, K. Abbas, M. U. Ijaz, S. Kumar, M. A. Hassan and S. Q. A. Shah Keywords: Fish, Toxicants, Enzymes, DNA damage, Organs INTRODUCTION [...]

Background Intensive aquaculture farming has caused significant degradation of coastal wetlands and has been proposed as a reservoir for pathogenic Vibrio spp. Results Gut pathogens including Vibrio spp., Salmonella spp., and Klebsiella spp. were isolated from bird feces, shrimp and wetland water in two typical coastal regions of China in 2015 and 2017 and were subsequently subjected to whole-genome sequencing. Meanwhile, local patient isolates were also selected to confirm the epidemiological links. Bacterial community composition analyses of the sediments that were sampled in 2015 and 2017 were conducted by the hypervariable region 4 of the 16S rRNA gene. Together with the local clinical isolates, we observed highly related Vibrio isolates from waterbirds, wetlands and shrimp. Phylogenetic genome comparisons also demonstrated that sequence types ST3 and ST2414 Vibrio parahaemolyticus isolates obtained from aquatic animals were clonally related to patient isolates. Likewise, three Salmonella typhimurium isolates were also genomically related to one clinical strain. The results showed that farming activities significantly altered the community composition and resulted in the emergence of several pathogens, including Acinetobacter, Mycobacterium and Legionella. Conclusions In conclusion, our results demonstrated that intensive shrimp farming in wetlands has two devastating impacts: pathogen dissemination from aquatic animals into migratory birds and transmission of foodborne pathogens into local communities. Keywords: Vibrio parahaemolyticus, Vibrio vulnificus, Wetlands, One health, Shrimp farming, Author(s): Qingyao Wang[sup.1,2], Yixiang Zhang[sup.3,4], Qian Yang[sup.5], Songzhe Fu[sup.1,2], Baocheng Qu[sup.1,2] and Tom Defoirdt[sup.5] Background Destruction of animal habitats has been associated with infectious disease emergence [1-3]. For instance, the [...]

Byline: J. Shafi, K. N. Waheed, Z. S. Mirza and M. Zafarullah Keywords: Aquaculture, site selection, soil salinity, particle size distribution, clay turbidity, water seepage INTRODUCTION Among the world food [...]