Exploring biophysical links of catch rate from mid-water trawl fishery in the north-west coast of India, Eastern Arabian Sea: A remote sensing approach.

Fish frequently shift their distribution ranges as a result of changes in preferred environmental factors. Knowledge on distribution of fish in relation to their environmental optima is crucial for improving the understanding of fishing grounds and planning sustainable exploitation. This study investigated the monthly variability in environmental factors impacting the catch rate and the spatio-temporal distribution patterns of fish along northwest coast of India (NWCI) from 2017 to 2019. The time series images of sea surface temperature (SST), sea surface height anomaly (SSHa), chlorophyll-a concentration (CHL), and euphotic depth (Zeu) indicate close coupling between bio-physical variables in the region. Generalized Additive Model (GAM) applied to the catch rate of mid-water trawlers found that CHL and Zeu were the most influential variables for ribbonfish distribution, while CHL and SST influence squid distribution and SST and SSHa influence cuttlefish distribution. The total deviation explained 37.70 %, 10.70 %, and 22.28 % in the final model for simulating the spatio-temporal distribution of ribbonfish, squid, and cuttlefish, respectively. Environmental factors were significant in the final GAM model (p < 0.05). Spatio-temporal distribution patterns of fishery resources from mid-water trawlers showed that they were related to biophysical changes in the northwest coast of India. The high catch rate was observed in the northern latitudes during the post-monsoon (October), the major fishing season in the region. However, it shrank and shifted to southern latitudes during the winter (January). This study could be adapted to nearby countries in the Arabian Sea region for an effective and useful tool to monitor and manage the fishery resources. Furthermore, it could aid in decision-making for policymakers and resource managers to formulate strategies for holistic marine fishery management and sustainable resource exploitation.

Escape Survival and Scale Damage Assessment of Red Mullet (Mullus barbatus Linnaeus, 1758) during Bottom Trawling in the Central Mediterranean Sea.

Stock assessments routinely evaluate the status of commercially harvested species, but seldom account for the possible mortality of released or escaping fish. This study presents a method for estimating the escape survival of the red mullet (Mullus barbatus) from demersal trawling in the Central Mediterranean Sea. Fish escaping from the trawl codend were collected in a detachable cage, which was lined to reduce water flow and protect the sampled fish from further fatigue and injury. Control fish (from an open codend) showed high survival, 94% (87-97%, 95% Confidence Interval), and minimal injuries, while fish escaping through codend meshes had significantly increased injuries and reduced survival, 63% (55-70%). During 7 days of captive monitoring, treatment group mortality was highest in the first 24 h and ceased for both groups within 48 h. Conflicting length-related mortality was observed, where larger treatment fish had a higher probability of dying, while the opposite was observed in the controls. Analysis showed that treatment fish were significantly more injured than control fish, with treatment fish predominantly injured in the head zone. In conclusion, this improved methodology should be repeated to provide accurate escape mortality estimates for the improved stock assessment of the red mullet in the Central Mediterranean.

Microplastic pollution of commercial fishes from coastal and offshore waters in southwestern Japan.

Microplastic (MP) pollution in the marine environment is a worldwide issue. There is growing concern of consuming MPs through fish, yet the contamination status of fish collected from deeper waters surrounding Japan remains limited. Here, we presented baseline data on MPs in commercially important fishes from the coastal and offshore waters near Kyushu, Japan (East China Sea). We examined the MPs in the digestive tracts of two pelagic (n = 150) and five demersal species (n = 235). The fish were caught by pole and line, and bottom trawl at different geographical positions. The MPs in pelagic fish (39.1%) were more than in demersal fish (10.3%) and were of larger sizes. Moreover, the MPs correlated with habitat depth and type and species variation in the shape and polymer composition of MPs was observed. The results increase our understanding of the heterogeneous uptake of MPs by fishes.

Produtos de pescado elaborados com resíduos de arrasto: análise físico-química, microbiológica e toxicológica / Fish products made from trawl fishery waste: physical, chemical, microbiologic, and toxicological analysis

Na pesca de arrasto, são inúmeras as espécies de peixe capturadas acidentalmente, compostas, em sua maioria, de espécimes de pequeno tamanho e baixo valor comercial, os quais recebem o nome de rejeito de pesca. O presente trabalho teve como objetivo o desenvolvimento de dois produtos, almôndega e quibe de peixe, tendo como matéria- prima espécies consideradas capturas acidentais na modalidade de pesca de arrasto realizada no litoral do Rio de Janeiro. A identificação taxonômica das espécies teve como resultado as espécies pargo (Pagrus pagrus), castanha (Umbrina sp.), olho-de-cão (Priacanthus arenatus), congro-negro (Conger sp.), congro-rosa (Genypterus brasiliensis) e peixe-sapo (Lophius gastrophysus). A matéria seca percentual na polpa foi de 31,20±1,30%, no quibe e na almôndega crus; os valores foram de 37,90±1,10 e 32,10±1,10, respectivamente. Nos produtos assados, os resultados foram 33,40±1,20 para o quibe e 34,20±1,00 para a almôndega. Os teores de cinzas na polpa foram 1,5% para o quibe e a almôndega crus; os valores de cinzas foram de 2,55±0,05 e 1,47±0,05, respectivamente. Para os produtos assados, os resultados foram 1,87±0,05 para o quibe e 1,92±0,05 para a almôndega. Os teores de lipídeos aferidos na polpa foram de 4,80±0,30%. Com relação ao quibe e à almôndega crus, o percentual de lipídeos foi de 4,20±0,80 e 4,20±0,60, respectivamente. Para os produtos assados, foi de 4,50±0,60 para o quibe e 4,40±0,60 para a almôndega. A proteína bruta apresentou, na polpa, um índice de 15,60±1,04%. Com relação ao quibe e à almôndega crus, 17,80±2,16 e 14,90±2,12, respectivamente. Para os produtos assados, 15,10±2,10 em ambos. Os compostos nitrogenados solúveis, formadores do NNP, apresentaram valores de 285mg NNP/100g de polpa de pescado crua, 291mg NNP/100g no quibe cru e 294mg NNP/100g na almôndega crua. Os resultados da contagem total de psicrotróficos mantiveram-se abaixo de log 7,0UFC/g, para contagem padrão em placas de microrganismos aeróbicos. Não foi constatada a presença de coliformes fecais Salmonella e Staphylococcus aureus. Também não foram detectados níveis de histamina e compostos à base de enxofre nas amostras.(AU)

Seafood products represent an important source of proteins and minerals as well as polyunsaturated fatty acids. However, its consumption in Brazil is very low in comparison to other kinds of meat. This may due to lack of skill in its preparation, making immensurable the importance of the search for new ways to market it, such as ready-made or semi-ready to serve products. The trawl fishery method often accidentally captures a variety of species, composed basically of low commercial value and size. Such catches are called "second-hand catch". With this in mind, this paper has as its main objective de development of two products: fish meatball and kibe, using what is considered accidental catches in the trawl fishery industry done on Rio de Janeiro's offshore as the raw material. The taxonomic identification of the species resulted in the species, Red porgy (Pagrus pagrus), Argentine croaker (Umbrina sp.), Atlantic bigeye (Priacanthus arenatus), Black cusk-eel (Conger sp.), Cusk-eel (Genypterus brasiliensis) and Blackfin goosefish (Lophius gastrophysus). The dry material of the raw product was 31.20±1.30%, in the raw meatball and kibbeh the values was 37.90±1.10 and 32.10±1.10, respectively, in the baked product the results was 33.40±1.20 and 34.20±1.00 (kibbeh and meatball). The ash content in the pulp was 1.5%, for the raw kibbeh and meatball, the amounts of ash were 2.55±0.05 and 1.47±0.05, respectively. For baked goods results were 1.87±0.05 for the kibbeh and 1.92±0.05 for the meatball. The measured lipid levels in the pulp was 4.80±0.30%. In respect, raw kibbeh and meatball, the percentage of lipids were 4.20±0.80 and 4.20±0.60, respectively. For baked goods was 4.50±0.60 for the kibbeh and 4.40±0.60 for the meatball. The protein level presented in the raw material was 15.60±1.04%, to the raw kibbeh and meatball was 17.80±2.16 and 14.90±2.12 and for the baked goods 15.10±2.10 both. Soluble nitrogen compounds shows values of 285mg/100g in the raw material, in the kibbeh NNP 291mg/100g and the meatball NNP 294mg/100g. The results of the total count of psychotropic remained below 7.0 log CFU/g, for standard count of aerobic microorganism plates. Fecal coliform bacteria, Salmonella, and Staphylococcus aureus were not present . The levels of histamine and sulfur basic compounds (H2S) were not detected in the samples.(AU)

When does fishing lead to more fish? Community consequences of bottom trawl fisheries in demersal food webs.

Bottom trawls are a globally used fishing gear that physically disturb the seabed and kill non-target organisms, including those that are food for the targeted fish species. There are indications that ensuing changes to the benthic invertebrate community may increase the availability of food and promote growth and even fisheries yield of target fish species. If and how this occurs is the subject of ongoing debate, with evidence both in favour and against. We model the effects of trawling on a simple ecosystem of benthivorous fish and two food populations (benthos), susceptible and resistant to trawling. We show that the ecosystem response to trawling depends on whether the abundance of benthos is top-down or bottom-up controlled. Fishing may result in higher fish abundance, higher (maximum sustainable) yield and increased persistence of fish when the benthos which is the best-quality fish food is also more resistant to trawling. These positive effects occur in bottom-up controlled systems and systems with limited impact of fish feeding on benthos, resembling bottom-up control. Fishing leads to lower yields and fish persistence in all configurations where susceptible benthos are more profitable prey. Our results highlight the importance of mechanistic ecosystem knowledge as a requirement for successful management.

Tiburones y rayss (subclase elasmobranchii) desartados por la flota de arrastrre camaronero en el caribe de Colombia / Sharks and Rays (Subclass Elasmobranchii) Discarded from Commercial Shrimp Trawlers at the Caribbean Sea of Colombia

Con el fin de obtener una aproximación a la estructura del ensamblaje de peces cartilaginosos extraídos por la flota de arrastre camaronero en la costa norte de Colombia, se evaluó la composición y abundancia de tiburones y rayas descartados en dos sectores del Caribe colombiano, entre agosto y noviembre de 2004. Mensualmente se analizaron lances de la flota de arrastre camaronero al interior de cada sector (norte: La Virgen y Portete; sur: Barú, cabo Tiburón, Cascajal, Cispatá, Morrosquillo, Ceycén, Mestizo, río Cedro, Tigua y Tortuguilla). Observadores a bordo de la flota comercial de arrastre camaronero muestrearon 1/5 de la captura previamente homogenizada, tomada al azar de una de las cuatro redes de la embarcación. En 30 lances se registró la presencia de 47 peces cartilaginosos, correspondientes a seis familias y ocho especies. La mayor Captura por Unidad de Esfuerzo (CPUE) en términos de biomasa se registró en ambas zonas durante septiembre, la menor en noviembre en la zona sur; el mayor valor del número de individuos se presentó en septiembre en la zona sur y el menor en noviembre, lo cual puede atribuirse a la mayor disponibilidad del recurso objetivo que está asociado al periodo de mayores lluvias que enriquece las aguas de los ambientes costeros y son usados como hábitat y zonas de alimentación por los peces cartilaginosos.

In order to have an approximation to the cartilaginous fishes assemblage structure exploited by commercial shrimp trawlers from the north coast of Colombia, composition and abundance of the discarded sharks and rays on two zones of the Colombian Caribbean, between August and November of 2004 were evaluated. Each month, a number of trawls were analyzed in each zone (north: La Virgen and Portete; south: Barú, Cabo Tiburón, Cascajal, Cispatá, Morrosquillo, Ceycén, Mestizo, Cedro river, Tigua and Tortuguilla). Observers were placed on board commercial shrimp trawlers, sampling 1/5 from the total capture, previously homogenized, which was randomly taken from one of the four nets of the vessel. Within 30 trawls, there were 47 cartilaginous fishes registered, belonging to six families and eight species. The largest capture per effort unit (CPUE) in biomass was registered on September in both zones, whereas the smallest happened on November in the south one. The greatest value in number of units was in September within the south zone and the opposite occurred in November, registering the smallest values. This could explain the great availability of the objective resource, directly associated with the heavier rainy season that enriches the waters of the coastal environment and characterizes the region, probably used as habitat and feeding grounds for the cartilaginous fishes.