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Wood basic density (WD) plays a crucial role in estimating forest biomass; moreover, improving wood-density estimates is needed to reduce uncertainties in the estimates of tropical forest biomass and carbon stocks. Understanding variations in this density along the tree trunk and its impact on biomass estimates is underexplored in the literature. In this study, the vertical variability of WD was assessed along the stems of large trees that had a diameter at breast height (DBH) ≥ 50 cm from a dense ombrophilous forest on terra firme (unflooded uplands) in Acre, Brazil. A total of 224 trees were sampled, including 20 species, classified by wood type. The average WD along the stem was determined by the ratio of oven-dry mass to saturated volume. Five models were tested, including linear and nonlinear ones, to fit equations for WD, selecting the best model. The variation among species was notable, ranging from 0.288 g cm−3 (Ceiba pentandra, L., Gaertn) to 0.825 g cm−3 (Handroanthus serratifolius, Vahl., S. Grose), with an average of 0.560 g cm−3 (±0.164, standard deviation). Significant variation was observed among individuals, such as in Schizolobium parahyba var. amazonicum (H. ex D.), which ranged from 0.305 to 0.655 g cm−3. WD was classified as low (≤0.40 g cm−3), medium (0.41–0.60 g cm−3), and high (≥0.61 g cm−3). The variability in WD along the stem differs by wood type. In trees with low-density wood, density shows irregular variation but tends to increase along the stem, whereas it decreases in species with medium- and high-density wood. The variation in WD along the stem can lead to underestimations or overestimations, not only in individual trees and species but also in total stocks when estimating forest biomass. Not considering this systematic bias results in significant errors, especially in extrapolations to vast areas, such as the Amazon. [ABSTRACT FROM AUTHOR]

This article provides a brief synthesis of the captive breeding of Mikrogeophagus ramirezi, also known as the ram cichlid, in an aquarium. The article discusses the selection of a healthy pair, creating an adequate environment with the right water parameters, feeding and nutrition, stimulating reproduction, courtship and egg deposition, incubating the eggs, caring for the fry, separating the juveniles, and continued monitoring and care. The article emphasizes the importance of maintaining stable water parameters, providing a suitable diet, and regularly cleaning the aquarium. Overall, reproducing M. ramirezi in an aquarium can be a beautiful and educational experience. [Extracted from the article]

New attempt to answer the questions: 1) what aquatic biological resources are possessed in the Russian Far-Eastern Seas and North Pacific and what is their quantity? 2) which of them and how many are caught annually? 3) are these resources managed rationally in Russia? 4) and what is the reason for current situation and can it be improved? Based on the data of trawl surveys, a GIS is created with maps of the biological resources distribution, separately for actually harvested, potentially commercial, and non-commercial ones. The biomass, potential yield and its cost are calculated for the Chukchi, Bering, Okhotsk, and Japan Seas and North-West Pacific. These water bodies are ranked by their value for commercial fisheries. The obtained estimates are compared with the data on annual catch, export, import, and consumption of fish products in Russia. Possibility of larger landing is concluded for each water body, in terms of the harvested species biomass. The harvest from the Okhotsk Sea alone can reach more than 5.2 million tons that exceeds the level of «strategic ceiling» for the entire Russian fishery proposed in «Strategy for development of the fisheries complex of Russian Federation for the period to 2030». For the whole water area under consideration, this level can be exceeded by 3.5–4.7 times, or even by 5.6 times if the potentially commercial species will be exploited. Dynamics of domestic catch, trade and consumption of the biological resources are analyzed. The conclusion is that socioeconomic conditions rather than the state of biological resources are the reason that Russia still does not harvest so much. Some measures are proposed to improve the management of the Russian fishery industry. The obtained results cah alsobe used for maintenance rational use of the biological resources, food security, and nature protection, including evaluation of cost for biological resources in certain water bodies and assessment of damage caused to the nature and biological resources by pollution, construction, oil and gas production, or technogenic accidents.

The thornback ray (Raja clavata) is the most important chondrichthyan in terms of landings in the Mediterranean Sea. Intense harvesting may induce negative genetic effects reducing the resilience of overfished species. For this reason, genetic diversity information should be considered in fisheries management and conservation policies.Microsatellite markers were used to unravel the genetic features (variability, connectivity, sex‐biased dispersal) of R. clavata populations, both at the small (around the coast of Sardinia, western Mediterranean Sea) and larger spatial scales (at the pan‐Mediterranean level, and between the Atlantic Ocean and the Mediterranean Sea).Individual clustering, multivariate and variance analyses rejected the hypothesis of genetic homogeneity, with significant genetic differences between Mediterranean and Atlantic rays, as well as within the Mediterranean Sea between its western and eastern basins. The data indicated that both the Strait of Gibraltar and the Sicilian Channel seem to be effective in limiting the dispersal of thornback ray individuals, but a further structuring was identified, with the significant genetic differentiation of the populations located in the Algero‐Provençal and Tyrrhenian basins. Such a fine‐scale arrangement suggests the occurrence of additional barriers to species dispersal. A lack of significant genetic differentiation, stable over the years, was measured at a local scale among R. clavata Sardinian samples.Several possible mechanisms, both biological and abiotic (e.g. migratory behaviour, waterfronts and oceanographic discontinuities), are discussed. Overall, the genetic data presented, both at the local and regional level, could represent the baseline information for the temporal monitoring of populations and assessing the effects of present or future fisheries‐related management actions.The data obtained are information of paramount importance for minimizing the gaps in our current knowledge of the genetic diversity of thornback rays and maximizing the information needed for the correct protection of R. clavata populations. [ABSTRACT FROM AUTHOR]

Gonadal development in limpets is well-known. However, the integration of fecundity data on coastal management actions remains overlooked. Here, we use fecundity of two exploited limpets (Patella ordinaria and P. aspera) to demonstrate its potential as a conservation tool to preserve the harvested populations of both species. From October 2021 to June 2022, 158 females of P. ordinaria and 70 of P. aspera were collected from the coastal rocky shores of the archipelago of Madeira (NE Atlantic Ocean). The fecundity in both species appears to be determinate, and estimated batch fecundity 365,638 ± 204,462 oocytes for P. ordinaria and 73,029 ± 43,496 oocytes for P. aspera. The presence of spawning individuals of both species until May is of significant relevance to their management and conservation. A harvest-ban (November-March) is currently implemented in the coastal governance actions of P. ordinaria and P. aspera. Based on the fecundity results, small adjustments can be made to further improve the conservation of adult individuals, which are important for the continuity of future generations. So far, fecundity data constitute an overlooked life trait of key importance to preserve populations of exploited species, primarily those with limited mobility such as semi-sessile littoral limpets.

With global plastic production reaching 400 million tons in 2022, concerns about plastic pollution in the seas are increasing day by day. Therefore we focused on the abundance, characteristics, and chemical composition of potential anthropogenic origin MPs within the gastrointestinal tracts (GITs) of 11 commercial fish species in the Gulf of İzmir, an area heavily impacted by human activities. Within the scope of the study, 152 fish were sampled, and microplastics were found in 64 fish. In total, 77 MPs were identified based on ATR-FTIR analysis. Significant differences were found between species regarding MP abundance. Among the species, Scomber scombrus showed the highest MP ingestion. The MP abundance in the GIT of fish decreases from surface to deeper waters. There were also significant differences (p < 0.05) in MP abundance between pelagic and demersal fish species. Results showed that 50.6 % of MPs were fragments, and 49.4 % were fibers. The most common color was black. Seven polymer types were identified, and PE was the most common. The size of the identified MPs ranged from 101 to 4901 μm, and the average value was 715.83 ± 860.66 μm. This study sheds light on the MP contamination within commercial fish species in the Gulf of İzmir and emphasizes the urgent need for enhanced marine ecosystem conservation strategies. Our findings can serve as a basis for future studies by providing essential baseline data for implementing necessary policies and regulations. • Eleven commercial fish species were examined. • The sampling was carried out in one of the gulfs where anthropogenic activities are the most intense. • Pelagic fish species contain significantly more MP than demersal species. • Microplastics were mostly fragments, PE and black in color. [ABSTRACT FROM AUTHOR]

Using a mathematical model consisting of two modules, i.e. the Bayesian Schaefer Model and Length-based Bayesian Biomass, the state of the commercial stocks of the round goby Neogobius melanostomus in the Gulf of Odessa (Black Sea, Ukraine) is studied for the period 2009-2020. The results of the analysis are compared with the quantitative population parameters of the Mediterranean blue mussels Mytilus galloprovincialis around the coast of Odessa. The results show that (i) round goby stocks in the study area are now critically low and (ii) there was a noticeable decrease in mussel abundance and biomass in recent years off the coast of Odessa. These data suggest that when the biomass of mussels shorter than 20 mm decreases, the commercial stocks of round goby are reduced in the subsequent year. [ABSTRACT FROM AUTHOR]

The red porgy (Pagrus pagrus) is a carnivore bottom dweller sparid, inhabiting flat sandy bottoms, rhodolith and seagrass beds of the Mediterranean Sea, the Western Atlantic (from Florida to Argentina) and the Eastern Atlantic (from Britain to Gabon). Along its native range, the red porgy is highly targeted by commercial and artisanal fisheries. In the past 40 years, the population decline of the species has been widely reported. In many locations, such as the Brazilian coast, stocks have collapsed. The central portion of the Brazilian coast harbours the largest rhodolith beds in the world and the highest levels of nektonic and benthic biodiversity. Along the rhodolith megahabitat, P. pagrus density is disproportionately higher (by 480%) than that of conspicuous benthic fishes inhabiting the same environment. Despite the ecological and economic importance of such an important species along its native range, little is known regarding its habitat use, niche availability and population responses to global warming. Here we present habitat affinities based on data sampled using baited remote stereo‐video systems, and modelled niche availability and global warming populational responses. Our findings reveal that the red porgy is a species highly associated with rhodolith beds along the central portion of the Brazilian coast. The presence of a disproportional density and biomass of the red porgy, compared to other marine fish species, indicates that the species plays a key ecological role as a carnivore, mesoconsumer and prey/predator tolerant species, maintaining essential ecological functions in the habitat. In a global warming scenario, the model predicted populational niche shifts poleward and a severe niche erosion at lower latitudes as expected. Conservation initiatives (implementation of Maine Protected Areas, trawling exclusion zones, mining exclusion zones, fisheries management policies) are urgent to secure future stocks of the red porgy and also preserve the fragile rhodolith beds they inhabit. [ABSTRACT FROM AUTHOR]

Simple Summary: The spiny lobster Palinurus elephas has been intensively harvested across its range and is generally considered overfished, with global landings declining sharply in the last few years. Despite its economic and ecological importance, limited information is available to perform stock assessments and make robust management decisions. Here, demographics and exploitation levels of P. elephas were determined from coastal areas of the Azores, and the relevance of these data for fisheries management and conservation planning was discussed. The spiny lobster Palinurus elephas has been intensively harvested across its range and is generally considered overfished, with global landings declining sharply from an average of 820 t in 1960–79 to 385 t in 2000–19. Despite its economic and ecological importance, limited information is available to perform stock assessments and make robust management decisions. In this study, demographics and exploitation levels of P. elephas were determined from coastal areas of the Azores, and the relevance of these data for conservation planning was discussed. Carapace length varied between 39.6 and 174.3 mm, with mean sizes decreasing by depth. Males reached larger sizes and grew faster than females but were less dominant. Lifespan was 43 years for females and 60 years for males. The estimated mean length at first capture was 101.65 mm—around 58% of its asymptotic length. Fishing mortality and exploitation levels were close to the optimal values, indicating an uncertain future for Azorean populations if stock assessment and management initiatives are not focused on this species. Conservation and management strategies may benefit from these results under the 'precautionary approach' principle. However, up–to–date and accurate catch and fishing effort data need to be urgently collected. [ABSTRACT FROM AUTHOR]

One of the forms of forest management is community forestry which is as an alternative to state-managed conservation. Knowledge of the wood potential and exploitable species is a prerequisite for the sustainable management of a community forest. This study carried out in the Cobaba community forest in Eastern Cameroon aimed to assess the floristic diversity and exploitable potential of timber species. A floristic inventory at a sampling rate of 8% was carried out and the volume of trees having reached the minimum exploitable diameter estimated. A total of 7736 commercial trees with dbh ≥20 cm were recorded, belonging to 65 species, 58 genera and 26 families. The Shannon–Weaver diversity index (H′) was 3.61. The density was 42.04 stems ha-1 and the basal area 16.43 m2 ha−1. A volume of timber of 31,929.21 m3 has been estimated for trees having reached the minimum exploitable diameter. About 30% of this volume is made up of high and medium commercial value species for which market demand exists. The most abundant species of high commercial value were Triplochyton scleroxylon, Entandrophragma cylindricum, and Milicia excelsa. For sustainable management and species conservation, we recommend that species with very low densities should be excluded from logging and for each species exploited, some well-conformed seed trees with a diameter greater than the minimum exploitable diameter should be left to ensure the renewal of the wood resource.

This article presents data on the contents of Fe, Mn, Cu, Zn, Ni, Pb, and Cd in the tissues of the tunic, muscular sac, stomach, digestive gland, and gonads of the ascidian Halocynthia aurantium Pallas, 1787 from Peter the Great Bay and Kievka Bay (Sea of Japan). The physiologically important elements Fe, Mn, and Zn prevailed in almost all organs of ascidians in terms of their concentration levels. Patterns of metal distribution in the organs and tissues of H. aurantium were determined depending on their age. The levels of content of Zn, Mn, and Cu were similar in the organs of 2- and 3-year-old individuals. The element concentrations were highest in the digestive gland (Zn), stomach (Zn, Cu), tunic (Mn), and gonads (Cu). The content of Mn in the tunic of H. aurantium from different biotopes was higher compared to other organs. The content of Pb in the tissues of H. aurantium from Kievka Bay was higher than that of the tissues of ascidians from the other studied localities. [ABSTRACT FROM AUTHOR]

The disordered growth of large cities around water bodies causes environmental damage due to discarded plastics and microplastics (MPs) that aquatic organisms can ingest. This study analyzed the occurrence, type, and abundance of MPs in the gastrointestinal contents of four species of commercial fish (120 total specimens), namely, Brazilian mojarra (Eugerres brasilianus) and mullets (Mugil curema, Mugil curvidens, and Mugil liza), obtained in Porto Seguro in Bahia, Brazil, between March and May 2019. A priori probability distributions were generated using a Bayesian approach and simulations to assess MP intake based on varying exposure amounts (θ = 0.2, θ = 0.5, and θ = 0.8). E. brasilianus (53.33%) and Mugil spp. (41.66%) were contaminated with some types of MPs. Black, blue, and green MPs dominated in the extracted samples, and most measured 1.0 mm in length or smaller. The dominant polymers identified using Fourier transform infrared spectroscopy (FTIR) were polyester, polypropylene, semi-synthetic rayon fiber, and polyamide 6 (nylon). The a posteriori probabilities of more than half the E. brasilianus and Mugil spp. ingesting MPs were 0.336 and 0.008, respectively, indicating that E. brasilianus is much more likely to ingest MPs. These simulations can be useful tools for assessing the environmental quality and local anthropic impact of MP ingestion by fish populations. [ABSTRACT FROM AUTHOR]

The review started in 195 volume of «Izvestiya TINRO» is continued. The most important aspects of a new concept of adaptive zone are illustrated on cited data and results of trawl and plankton surveys collected by Pacific Fish. Res. Center (TINRO) in the FarEastern Seas and North Pacific for several decades. Practical benefits of this concept are shown and prospects of its further application are outlined, as managing of fishery and aquaculture and some issues of agriculture, forestry, hunting, natural nidality, fighting against alien species, weeds, pests and parasites, environmental protection and preservation, and artificial ecosystems creation.

Portable fish traps are a popular gear in reef fisheries, mainly in tropical and subtropical regions. As fish traps can be highly non-selective, catch composition may be composed of a variety of species. Commonly, fishers target predatory fish species of high trophic levels. However, in areas facing overfishing, there is a tendency towards a decrease in the proportion of these species in catches followed by their substitution with miscellaneous fish species of lower trophic levels, previously considered as by-catch, but nowadays marketable. In addition, some highly valuable fish species are commercially extinct and are caught rarely. In this review, we aim to shed light on the species targeted across the main trap fisheries worldwide, as well as to identify characteristics of these species that may be feasible to use as conservation tools to preserve stocks. Although a considerable number of species gain fishers' attention, we have revealed a significant lack of information regarding their population dynamics. Almost 65 % of species of high fishery interest remain unexamined, and approximately 76.5 % of those that have been examined are decreasing in biomass or (and) abundance. Further research is required for the evaluation of the dynamics of fish populations and socioeconomic factors that influence fisheries management plans and decision-making for the retained and discarded species. [ABSTRACT FROM AUTHOR]

Natural mortality (M) is a powerful parameter in fisheries stock assessment and management; however, its precise estimation is extremely difficult. There is still a lack of estimates for several stocks. That is the case of demersal/deep-water species from the Azores archipelago, where demersal species are the second most important fishery based on landings and the most important in value. Species with higher commercial value and lacking M data were selected: Pagellus bogaraveo, Phycis phycis, Beryx splendens, Pontinus kuhlii, Helicolenus dactylopterus, Pagellus acarne, Beryx decadactylus and Pagrus pagrus. Life history parameters were gathered from literature. A literature review was performed to summarize all published indirect methods that are commonly used, as a simple and low-cost way to estimate M. This study aims to demonstrate the variability of natural mortality estimates based on the input parameters. It also constitutes the first attempt of M estimation for the most commercially important Azorean species. Twenty-six indirect methods were applied and about 70 % of the selected species had an average mortality estimate between 0.22 and 0.34 per year. The most well-studied species (Pagellus bogaraveo and Helicolenus dactylopterus) provided more accurate mean estimations (M = 0.30 and M = 0.27, respectively). Independent methods based on Tmax alone, or combined with L∞ or W∞, lowered the values. Methods based on reproduction parameters alone, or combined with growth, inflated the estimations. From the selection of life history parameters to the final estimation of M, the results of this study can fill the existing gap and represent a starting point for further studies. [ABSTRACT FROM AUTHOR]

The spiny lobster Palinurus elephas has been intensively harvested across its range and is generally considered overfished, with global landings declining sharply from an average of 820 t in 1960–79 to 385 t in 2000–19. Despite its economic and ecological importance, limited information is available to perform stock assessments and make robust management decisions. In this study, demographics and exploitation levels of P. elephas were determined from coastal areas of the Azores, and the relevance of these data for conservation planning was discussed. Carapace length varied between 39.6 and 174.3 mm, with mean sizes decreasing by depth. Males reached larger sizes and grew faster than females but were less dominant. Lifespan was 43 years for females and 60 years for males. The estimated mean length at first capture was 101.65 mm—around 58% of its asymptotic length. Fishing mortality and exploitation levels were close to the optimal values, indicating an uncertain future for Azorean populations if stock assessment and management initiatives are not focused on this species. Conservation and management strategies may benefit from these results under the ‘precautionary approach’ principle. However, up–to–date and accurate catch and fishing effort data need to be urgently collected.

Summary: This work analysis the length‐weight relationships for fish species captured by artisanal fishery along the continental coast of Ecuador. Fishermen used the following fishing gear: beach seine nets (5.1–31.8 mm), shrimp trawl nets (21.8–31.8 mm) and bottom gill nets (54.1–203.2 mm). Sampling took place during the years 2012 and 2014. Frequency of sampling was monthly, and it was completed systematically from Southern toward Northern Provinces. Length‐weight relationship (LWR) was realized by the power model (y = a × xb), for species with a bivariate dataset >70. A total of 59 commercial and 15 non‐commercial species were registered. For 74 species, our analysis including a higher total length not reported in LWR estimates previously. The determination coefficient (r2) value was always above 0.95. [ABSTRACT FROM AUTHOR]

This work presents a guidance to conduct stock assessment based on ICES Maximum Sustainable Yield framework. A cross-analysis based on the models' assumptions and inputs and data available for 22 Azorean priority stocks was performed to assess the applicability of each model to each stock. Information currently available for coastal and some demersal/deep-water stocks limits the use of most models validated by ICES. Only four demersal/deep-water stocks (Pagellus bogaraveo, Helicolenus dactylopterus, Phycis phycis, and Pontinus kuhlii) have data availability and quality enough to perform trend analysis, length-based and catch and survey-based methods. The next steps involve validating life-history parameters, evaluating model performances, and applying alternative tools for data-deficient stocks. Additional monitoring programs are of utmost importance, which must collect missing information and clarify stock delimitation to improve assessment quality. This study guides future stock assessment actions and highlights data gaps where future research should focus. [ABSTRACT FROM AUTHOR]

Cold-seep benthic communities in the Arctic exist at the nexus of two extreme environments; one reflecting the harsh physical extremes of the Arctic environment and another reflecting the chemical extremes and strong environmental gradients associated with seafloor seepage of methane and toxic sulfide-enriched sediments. Recent ecological investigations of cold seeps at numerous locations on the margins of the Arctic Ocean basin reveal that seabed seepage of reduced gas and fluids strongly influence benthic communities and associated marine ecosystems. These Arctic seep communities are mostly different from both conventional Arctic benthic communities as well as cold-seep systems elsewhere in the world. They are characterized by a lack of large specialized chemo-obligate polychetes and mollusks often seen at non-Arctic seeps, but, nonetheless, have substantially higher benthic abundance and biomass compared to adjacent Arctic areas lacking seeps. Arctic seep communities are dominated by expansive tufts or meadows of siboglinid polychetes, which can reach densities up to >3 × 105 ind.m–2. The enhanced autochthonous chemosynthetic production, combined with reef-like structures from methane-derived authigenic carbonates, provides a rich and complex local habitat that results in aggregations of non-seep specialized fauna from multiple trophic levels, including several commercial species. Cold seeps are far more widespread in the Arctic than thought even a few years ago. They exhibit in situ benthic chemosynthetic production cycles that operate on different spatial and temporal cycles than the sunlight-driven counterpart of photosynthetic production in the ocean’s surface. These systems can act as a spatio-temporal bridge for benthic communities and associated ecosystems that may otherwise suffer from a lack of consistency in food quality from the surface ocean during seasons of low production. As climate change impacts accelerate in Arctic marginal seas, photosynthetic primary production cycles are being modified, including in terms of changes in the timing, magnitude, and quality of photosynthetic carbon, whose delivery to the seabed fuels benthic communities. Furthermore, an increased northward expansion of species is expected as a consequence of warming seas. This may have implications for dispersal and evolution of both chemosymbiotic species as well as for background taxa in the entire realm of the Arctic Ocean basin and fringing seas.

The reduction of the fish and non-fish resources in the World Ocean (in particular in the Black Sea) over the last 20 - 30 years is an indisputable fact. This is due to many factors, but anthropogenic ones are dominant. Among them the most important are overfishing of hydrobionts, poor water quality and climate change. A real alternative to compensate these losses and to creat healthy sources of quality seafood for humans is aquaculture - technology that can satisfy the "protein" hunger worldwide. In this regard, the purpose of the present article is to analyze the state of the Bulgarian Black Sea aquaculture and to outline the prospects for its development, based on native and introduced marine species. Modern aquaculture production in Bulgaria is dominated by the production cyprinids and salmonids in freshwater aquaculture farms, and by black mussel (Mytilus galloprovincialis) only in marine aquaculture farms. This imbalance (81.7% vs 18.3%) shows that the resources of the Bulgarian Black Sea water areas are not used sufficiently for this purpose. The indepth analysis of available literature sources (scientific articles, official reports, monographs, plans and programs, etc.), as well as the shared experience of colleagues from China, the world leader in the field of fish farming and aquaculture, give us grounds to consider the following species as promising for cultivation in the Bulgarian Black Sea water areas: Rainbow trout (Oncorhynchus mykiss Walbaum, 1792), Mullet (Mugil cephalus Linnaeus, 1758), Turbot (Psetta maxima Linnaeus, 1758), White mussel (species of bivalve molluscs: Chamelea galina Linnaeus, 1758, Donax trunculus Linnaeus, 1758, Mya arenaria Linnaeus, 1758 and Anadara kagoshimensis Tokunaga, 1906), Rapana (Rapana venosa Valenciennes, 1846), shrimp, micro- and macro- algae, introduced marine species like Sea cucumber (Holothuroidea). Future studies will show which species are environmentally friendly and cost-effective for cultivation in Bulgarian Black Sea aquatory. [ABSTRACT FROM AUTHOR]

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The objective of this study was to assess the patterns in the spatial distribution, size structure, morphometric relationships, and relationships of biomass and size to sampling depth and distance to the coast of Penaeus notialis in the Colombian Caribbean. The biological data were collected on board a shrimp trawler. The females were larger and heavier than the males, which indicated distinct sexual dimorphism in body size. The cephalothorax length at 50% maturity in females was 26.49 mm, and in males, it was 15.13 mm. Relatively high biomass values were found in the southern zone of the study area at depths between 25.6 and 49.3 m and between 3.94 and 7.80 nmi (= 7.29-14.45 km) from the coast. We found a clear spatial structure of biomass and size in relation to depth, so that the fishing effort can be directed to the locations of the adult population. Resumen: El objetivo de este estudio fue evaluar los patrones de distribución espacial, estructura de tallas, relaciones morfométricas, y relaciones de la biomasa y tallas con la profundidad y distancia de la costa de Penaeus notialis en el Caribe colombiano. Los datos biológicos fueron tomados a bordo de un barco camaronero arrastrero. Las hembras fueron más grandes y pesadas que los machos, mostrando un distinto dimorfismo sexual en tamaño. La longitud al 50% de madurez del cefalotórax en hembras fue 26.486 mm y en machos 15.134 mm. Valores relativamente altos de biomasa fueron encontrados en la zona sur del área de estudio, en profundidades entre 25.6 y 49.3 m y distancia de la costa de 3.94 a 7.80 nmi (= 7.29-14.45 km). Se encontró una clara estructura especial de la biomasa y las tallas relacionadas con la profundidad, para que el esfuerzo se pueda dirigir donde la población adulta está localizada. [ABSTRACT FROM AUTHOR]

A total of 28 taxa belonging to 18 genera, 16 families and 6 orders under the class Bivalvia of the phylum Mollusca were presently identified. These specimens included 2 species of Anadara, 1 species of Perna, 1 species of Placuna, 2 species of Crassostrea, 1 species of Saccostrea, 1 species of Lucina, 1 species of Trachycardium, 3 species of Mactra, 2 species of Pharella, 1 species of Solen, 1 species of Tellina, 2 species of Donax, 2 species of Gari, 1 species of Azorinus, 3 species of Polymesoda, 2 species of Meretrix, 1 species of Pholas and 1 species of Bactronophorus. Among the collected specimens, Saccostrea species were represented as a dominant species followed by Meretrix and Mactra species within the study period. In all study areas, Kawmawkinn station of Ye River Mouth area is more dominant than other stations. Moreover, habitats, local distribution and utilization of each species were also presented. [ABSTRACT FROM AUTHOR]

• Species distribution and spatial food web models are used to predict presence and biomass distribution of commercial species. • We explore the complementarity of both approaches aside from their applicability as independent techniques. • Both modelling results are positively and significantly correlated with observational data from the NW Mediterranean Sea. • Predicted spatial patterns show positive and significant correlations between modelling tools. • Results from both modelling tools are more similar when using both methodologies in a complementary way. The spatial prediction of species distributions from survey data is a significant component of spatial planning and the ecosystem-based management approach to marine resources. Statistical analysis of species occurrences and their relationships with associated environmental factors is used to predict how likely a species is to occur in unsampled locations as well as future conditions. However, it is known that environmental factors alone may not be sufficient to account for species distribution. Other ecological processes including species interactions (such as competition and predation), and the impact of human activities, may affect the spatial arrangement of a species. Novel techniques have been developed to take a more holistic approach to estimating species distributions, such as Bayesian Hierarchical Species Distribution model (B-HSD model) and mechanistic food-web models using the new Ecospace Habitat Foraging Capacity model (E-HFC model). Here we used both species distribution and spatial food-web models to predict the distribution of European hake (Merluccius merluccius), anglerfishes (Lophius piscatorius and L. budegassa) and red mullets (Mullus barbatus and M. surmuletus) in an exploited marine ecosystem of the Northwestern Mediterranean Sea. We explored the complementarity of both approaches, comparing results of food-web models previously informed with species distribution modelling results, aside from their applicability as independent techniques. The study shows that both modelling results are positively and significantly correlated with observational data. Predicted spatial patterns of biomasses show positive and significant correlations between modelling approaches and are more similar when using both methodologies in a complementary way: when using the E-HFC model previously informed with the environmental envelopes obtained from the B-HSD model outputs, or directly using niche calculations from B-HSD models to drive the niche priors of E-HFC. We discuss advantages, limitations and future developments of both modelling techniques. [ABSTRACT FROM AUTHOR]

The United States Food and Drug Administration (FDA) has recently adopted DNA barcoding for the purpose of determining the species identity of commercial seafood products. This effort has revealed instances of incongruence between current scientifically accepted taxon names and those utilized by the seafood industry in product labelling. One such case is that of "Portunus haanii", a name utilized by the seafood industry to label commercial products under the market name "red swimming crab." However, carcinologists currently regard P. haanii as synonym of Portunus gladiator Fabricius, 1798, which itself is the subject of debate over whether it is a secondary homonym of Cancer gladiator Fabricius, 1793. Further complicating matters, DNA barcode sequences from commercial products match GenBank sequences identified as Portunus pseudoargentatus Stephenson, 1961. Here the complicated taxonomic history of the Portunus gladiator complex is reviewed and a resolution proposed based on combined morphological descriptions and molecular phylogenetic analyses. It is demonstrated that, given the provisions of the International Code of Zoological Nomenclature and the current elevation of Monomia Gistel, 1848, to full genus rank, its type species, Portunus gladiator Fabricius, 1798, should be treated as a valid and available taxon name. It is also shown, upon examination and comparison of types and topotypic material that Monomia haanii (Stimpson, 1858) is a distinct taxon from M. gladiator, and Portunus pseudoargentatus Stephenson, 1961, is a junior subjective synonym of M. haanii (Stimpson, 1858). Furthermore, it is shown that crab meat sold in the US currently labeled as "Portunus haanii" and/or "red swimming crab" is in fact M. haanii using comparative analysis of DNA barcode sequences between museum-vouchered reference specimens, whole crabs provided directly by a seafood importer, and processed commercial products purchased at retail. [ABSTRACT FROM AUTHOR]

Structural and Ecological Characteristics of Commercial Timber species' population: a Basis for Silviculture in Niaouli Forest Stands (Southern Benin). This study was carried out to provide silvicultural guidance in the Niaouli forest (6°43'- 6°44'N and 2°07'- 2°08'E), Southern Benin, based on commercial species. Twenty-three 0.25 ha plots (50 m x 50 m) were set to characterize the structure and the ecology of these species' populations. Within each plot of 0.25 ha, three 100 m² sub-plots (10 m × 10 m) were set for the assessment of regeneration. A multidimensional scaling was performed with SPSS 16.0 on presence-absence data of species, and led to the identification of four forest stands. Overall, the number of species and their abundance in the stands were linked to the presence of water. Diameter structure and regeneration revealed that the populations of the studied species were not at equilibrium. The silvicultural interventions suggested to equilibrate them were as follows: enrichment of the forest stands with the studied species; removal of liana and clearing of the undergrowth to enable the germination of seeds and the growth of the seedlings of commercial species, and the protection of the forest from illegal logging by improving security.

This paper presents the results of the parasitological research on parasite infestation at the main fish species of commercial interest on the Romanian Black Sea coast: Sprattus sprattus - sprat, Engraulis encrasicholus - anchovy, Trachurus mediteraneus ponticus - horse mackerel, Psetta maxima maeotica - turbot. The investigations were carried out between 2016 and 2017, on fish collected from Sulina to Vama Veche. The following species of ectoparasites were identified: the ciliate - Trichodina domerguei, and the flat worm - Mazocraes alose and the endoparasites: Contracaecum aduncum, Contracaecum sp., Anisakis sp., Porrocaecum sp. and the flat worm Botriocephalus scorpii were found. Ectoparasites, including those outside the body affecting fish species, especially the substrate of skin, fins, gills and eyes were rather low in number. Trichodinina domerguei affected fish outside the body, fins and gills and Mazocraes alose affected only the gills. Specific analysis made to evaluate the effects of nematode worm parasites on the status of fish populations revealed high values of prelevance (percentage of infested fish), mean infestation intensity and abundance of parasites being higher in larger specimens compared to the smaller ones. Thus, for sprat, the larger specimens, 10-11 cm in length, reached 80% and anchovy 11-12 cm length reached 100%, while the specimens under these lengths were 40-70% infested. The flat worm Botriocephalus scorpii, found in turbot stomach in very large numbers, caused severe lesions, especially inflammations, wounds, desquamation of the damaged epithelium. Toxic substances released by the worms are absorbed and produce whole body intoxication. The presence of these parasites in natural fish populations may represent a real danger to the state of existing stocks, but also to their evolution. [ABSTRACT FROM AUTHOR]

We have learned much about the impacts of warming on the productivity and distribution of marine organisms, but less about the impact of warming combined with other environmental stressors, including oxygen depletion. Also, the combined impact of multiple environmental stressors requires evaluation at the scales most relevant to resource managers. We use the Gulf of St. Lawrence, Canada, characterized by a large permanently hypoxic zone, as a case study. Species distribution models were used to predict the impact of multiple scenarios of warming and oxygen depletion on the local density of three commercially and ecologically important species. Substantial changes are projected within 20-40 years. A eurythermal depleted species already limited to shallow, oxygen-rich refuge habitat (Atlantic cod) may be relatively uninfluenced by oxygen depletion but increase in density within refuge areas with warming. A more stenothermal, deep-dwelling species (Greenland halibut) is projected to lose ~55% of its high-density areas under the combined impacts of warming and oxygen depletion. Another deep-dwelling, more eurythermal species (Northern shrimp) would lose ~4% of its high-density areas due to oxygen depletion alone, but these impacts may be buffered by warming, which may increase density by 8% in less hypoxic areas, but decrease density by ~20% in the warmest parts of the region. Due to local climate variability and extreme events, and that our models cannot project changes in species sensitivity to hypoxia with warming, our results should be considered conservative. We present an approach to effectively evaluate the individual and cumulative impacts of multiple environmental stressors on a species-by-species basis at the scales most relevant to managers. Our study may provide a basis for work in other low-oxygen regions and should contribute to a growing literature base in climate science, which will continue to be of support for resource managers as climate change accelerates. [ABSTRACT FROM AUTHOR]

We analysed data collected on board commercial purse seine vessels in the Aegean and Ionian Seas (eastern Mediterranean Sea, Greece) in 13 seasonal sampling periods from 2003 to 2008 in order to describe the composition of the retained and discarded catch and shed light on discarding practices. In each area, five species constituted the majority of the marketable catch (> 97%): sardine (Sardina pilchardus), anchovy (Engraulis encrasicolus), round sardinella (Sardinella aurita), bogue (Boops boops) (in both areas), mackerel (Scomber japonicus; in the Aegean Sea) and picarel (Spicara smaris; in the Ionian Sea). Discarded quantities were on average 4.6% and 2.2% of the total catch in terms of weight in the Aegean and Ionian Seas respectively. Discards on the marketable ratio fluctuated over years and seasons without showing any particular trend. At the species level, sardine and mackerel were seldom discarded while large amounts of anchovy were discarded only during its recruitment period (autumn), when juvenile fish dominate the population. The discarding ratio for bogue, picarel and round sardinella ranged from zero to total discarding because they constitute a supplementary source of income for the fishers. Discarded fish comprised mainly small individuals for all species considered with the exception of round sardinella. However, the lengths at which 50% of the individuals were discarded were generally small, often smaller than the species minimum landing sizes. Geographical coordinates and marketable catch explained part of the variability of the discarded quantities, as revealed by generalized additive models. Discarding practices and implications for management of purse seine fisheries are also discussed.

This study was carried out to provide silvicultura! guidance in the Niaouli forest (6°43'- 6°44'N and 2°07'- 2°08'E), Southern Benin, based on commercial species. Twenty-three 0.25 ha plots (50 m x 50 m) were set to characterize the structure and the ecology of these species' populations. Within each plot of 0.25 ha, three 100 m² sub-plots (10 m x 10 m) were set for the assessment of regeneration. A multidimensional scaling was performed with SPSS 16.0 on presence-absence data of species, and led to the identification of four forest stands. Overall, the number of species and their abundance in the stands were linked to the presence of water. Diameter structure and regeneration revealed that the populations of the studied species were not at equilibrium. The silvicultural interventions suggested to equilibrate them were as follows: enrichment of the forest stands with the studied species; removal of liana and clearing of the undergrowth to enable the germination of seeds and the growth of the seedlings of commercial species, and the protection of the forest from illegal logging by improving security. [ABSTRACT FROM AUTHOR]

Mixed maerl beds (corralline red algae) comprise dead thalli with varying amounts of live maerl fragments, but previously it was not known whether the presence of the live maerl increases the ecosystem service ‘habitat provision’ of the dead maerl for the associated epibenthos. A ‘flying array’ towed sled with high definition video was used to film transects of the epibenthos in dead maerl and mixed maerl beds in two locations to the north and south of the English Channel (Falmouth and Jersey). Mixed maerl beds supported greater number of taxa and abundance than dead beds in Falmouth, while in Jersey, mixed and dead beds supported similar number of taxa and dead beds had a greater abundance of epifauna. Scallops tended to be more abundant on mixed beds than dead beds. Tube worms were more abundant on mixed beds in Falmouth and dead beds in Jersey. An increasing percentage occurrence of live maerl thalli correlated with increasing number of taxa in Falmouth but not Jersey. It was concluded that while live thalli can increase the functional role of dead maerl beds for the epibenthos, this is dependent on location and response variable. As a result of this work, maerl habitat in SE Jersey has been protected from towed demersal fishing gear. [ABSTRACT FROM AUTHOR]

Bioaccumulation of trace metals in the food web demands continuous monitoring of seafood safety. Here, the food safety of commercial fish bluespot mullet Crenimugil seheli , deep flounder Pseudorhombus elevates, and Jinga shrimp Metapenaeus affinis was assessed from commercial and industrial region of the West Bandar Abbas, the North Persian Gulf, for the first time. For this purpose, concentrations of trace metals Ni, Zn, Cu, Cr, Cd, and Pb, and their health risks were investigated. Results showed the average concentration of all trace metals in all species was below concentrations proposed by WHO/FAO/USEPA. The finding on risk assessment of three species indicated three species are safe for daily consumption. Long-term consumption of three species would not pose potential non-carcinogenic health risk. However, it would result in carcinogenic effects from the ingestion of trace metals Ni, Cr, and Cd. The data emphasizes the need for the continuous monitoring in this industrial region in the future to manage and control pollutant sources and to ensure the quality of seafood. [ABSTRACT FROM AUTHOR]

Distributional pattern and qualitative composition of ichthyoplankton in waters of the Southern Pacific in September 2002-January 2003 and in August-November 2009 are analyzed. We noted approximately 70 species of fish pelagic eggs and larvae of fishes belonging to 34 families in this region. Change in distribution of the basic object of commercial fishery of this region, i.e., Peruvian-Chilean jack mackerel Trachurus murphyi, in early ontogenesis are considered in detail. The obtained data on the species composition, distribution, and abundance of ichthyoplankton in this region are compared with the results of investigations in the past years. The spawning biomass of jack mackerel is also estimated in the work by the amount of the eggs spawned by females in the places of their greatest concentrations. [ABSTRACT FROM AUTHOR]

The article discusses findings of a study which evaluated temporal patterns in the abundance and distribution of reef fishes at Glover's Atoll in Belize. In 1998, a no-take marine reserve was enforced at the site. Preserve spatial distribution of fishes with respect to reserve boundaries is a significant predictor of species responses to reserve protection. The examined mechanisms for the observed temporal changes to responses of species towards protection in a managed area with a no-take reserve include explicit habitat changes that may affect different species, life-history characteristics, differing susceptibility of fish species to the fishery and differences between species in the effect of the reserve on fishing mortality.

Abstract: This paper assesses the potentials of the available time series (50 years+) from historical records of the pre-industrial period until c. 1850–1950. A number of historical records from commercially important fish species are available for examining natural variability of fish stocks. Especially for North Atlantic and Japanese fisheries historical data have been retrieved from archives and museums, which cover time spans of 50–350 years. This makes it possible to examine natural variability of fish stocks over a much longer time span than what is normally possible with modern survey data and commercial catch data. Furthermore, historical evidence from the pre-industrialized period have the benefit of stemming from a period in time, when fishing had an insignificant impact on the abundance of open sea fish stocks. The best material comes from cod and herring fisheries, where it is possible to reconstruct CPUE as accurate as catch per boat per day absent, as well as changing spatial distribution over longer time periods. [Copyright &y& Elsevier]

From the data of commercial landings and underwater observations on the Vavilov Ridge (the eastern part of the Atlantic Ocean), approximately 50 bottom, near bottom, and near bottom-pelagic fish species of 38 families are recorded. The following species have the highest commercial importance: mackerel scads Decapterus longimanus,and D. macarellus,,mackerel Scomner japonicus, Beryx splendens, Allocyttus guineensis, Epigonus affinis,,etc. [ABSTRACT FROM AUTHOR]