ABSTRACT
Many small-scale fisheries (SSFs) in Latin America and the Caribbean (LAC) operate in ecologically sensitive areas, where balancing conservation and resource use is challenging. 'Multiple-use' marine protected areas (MPAs) have been implemented to accommodate SSFs (among other uses) within areas designated for conservation, creating opportunities and challenges for SSF governance. We analyzed eleven case studies from LAC to explore: (1) how different MPA institutional designs affect key aspects of SSF governance and (2) the links between these effects and the type of initiative that promoted MPA establishment (origin). Results indicate that the existence of an MPA benefited SSF governance in many ways, with more pronounced positive effects in MPAs with mixed to bottom-up origin supported by well-organized fishing groups. In addition, the presence of supportive MPA authorities that leveraged local capacities and initiatives and adopted flexible and collaborative governance systems made a difference in several cases. Lessons for integrating MPA and SSF governance are drawn.
ABSTRACT
The illegal trade in totoaba (Totoaba macdonaldi) is causing adverse social, ecological, and economic impacts. This illegal activity is accelerating the overexploitation of totoaba and pushing the critically endangered vaquita (Phocoena sinus) closer to extinction. Despite extensive efforts to recover vaquita populations, scant attention has been given to the totoaba trade as an independent issue. As a result, data on the totoaba trade are limited, which hampers robust analyses and development of effective interventions to reduce illegal harvesting. We used a previously developed framework specifically designed to examine dynamics of illegal markets and guide measures to mitigate illegal use of totoaba. This framework separates markets into 3 analytical levels: characterization of participating actors (e.g., fishers, intermediaries); examination of how actors interact within the market (e.g., organization of supply chains); and assessment of the overall market dynamics that result from these interactions (e.g., factors determining price and quantity). We reviewed existing literature (108 initial articles) and interviewed key market actors, academics, and nongovernmental organization experts (14) to obtain data for this framework. Our findings offer an overview of the totoaba illegal market operation, highlighting intervention points (e.g., customs agents) and areas where additional information is required to decrease information gaps (e.g., US local market). We describe the structure and complexity of this market, emphasizing the influential role of organized crime in shaping its dynamics (e.g., controlling prices paid to fishers and stockpiling). By providing a systematic and in-depth understanding of the market operation, we aimed to establish a benchmark for effective interventions and future research aimed at reducing uncertainties. Our results provide a crucial step toward addressing this critical issue and can help facilitate development of effective strategies to combat the illegal totoaba trade and promote biodiversity conservation more broadly.
Evaluación de las intervenciones potenciales para reducir el mercado ilegal de la totoaba Resumen El mercado ilegal de totoaba (Totoaba macdonaldi) causa impactos sociales, ecológicos y económicos adversos. Esta actividad ilegal acelera la sobreexplotación de la totoaba y acerca a la extinción a la vaquita marina (Phocoena sinus), especie en peligro crítico de extinción. A pesar de los grandes esfuerzos por recuperar las poblaciones de vaquita, el comercio de totoaba recibe poca atención como problema independiente. Como resultado, los datos sobre este comercio son limitados, lo que dificulta el análisis sólido y el desarrollo de intervenciones eficaces para reducir la captura ilegal. Utilizamos un marco desarrollado previamente y diseñado específicamente para examinar la dinámica de los mercados ilegales y orientar las medidas para mitigar el uso ilegal de la totoaba. Este marco separa los mercados en tres niveles analíticos: caracterización de los actores participantes (por ejemplo, pescadores, intermediarios); análisis de cómo interactúan los actores dentro del mercado (por ejemplo, organización de las cadenas de suministro); y evaluación de la dinámica general del mercado que resulta de estas interacciones (por ejemplo, factores que determinan el precio y la cantidad). Revisamos la bibliografía existente (108 artículos iniciales) y entrevistamos a actores clave del mercado, académicos y expertos de organizaciones no gubernamentales (14) para obtener datos para este marco. Nuestras conclusiones ofrecen una visión general del funcionamiento del mercado ilegal de totoaba y destacan los puntos de intervención (por ejemplo, los agentes aduanales) y las áreas en las que se requiere información adicional para reducir los vacíos informativos (por ejemplo, el mercado local estadunidense). Describimos la estructura y complejidad de este mercado, destacando el influyente papel de la delincuencia organizada en la configuración de su dinámica (por ejemplo, controlando los precios pagados a los pescadores y el almacenamiento). Al proporcionar una comprensión sistemática y en profundidad del funcionamiento del mercado, pretendemos establecer un punto de referencia para intervenciones eficaces y futuras investigaciones encaminadas a reducir las incertidumbres. Nuestros resultados suponen un paso crucial para abordar esta cuestión crítica y pueden ayudar a facilitar el desarrollo de estrategias eficaces para combatir el comercio ilegal de totoaba y promover la conservación de la biodiversidad de forma más amplia.
Subject(s)
Commerce , Conservation of Natural Resources , Conservation of Natural Resources/legislation & jurisprudence , Conservation of Natural Resources/economics , Conservation of Natural Resources/methods , Commerce/legislation & jurisprudence , Animals , Endangered Species/legislation & jurisprudence , Crime/prevention & control , Fisheries/legislation & jurisprudence , Fisheries/economicsABSTRACT
Climate change brings a range of challenges and opportunities to shrimp fisheries globally. The case of the Colombian Pacific Ocean (CPO) is notable due the crucial role of shrimps in the economy, supporting livelihoods for numerous families. However, the potential impacts of climate change on the distribution of shrimps loom large, making it urgent to scrutinize the prospective alterations that might unfurl across the CPO. Employing the Species Distribution Modeling approach under Global Circulation Model scenarios, we predicted the current and future potential distributions of five commercially important shrimps (Litopenaeus occidentalis, Xiphopenaeus riveti, Solenocera agassizii, Penaeus brevirostris, and Penaeus californiensis) based on an annual cycle, and considering the decades 2030 and 2050 under the Shared Socioeconomic Pathways SSP 2.6, SSP 4.5, SSP 7.0, and SSP 8.5. The Bathymetric Projection Method was utilized to obtain spatiotemporal ocean bottom predictors, giving the models more realism for reliable habitat predictions. Six spatiotemporal attributes were computed to gauge the changes in these distributions: area, depth range, spatial aggregation, percentage suitability change, gain or loss of areas, and seasonality. L. occidentalis and X. riveti exhibited favorable shifts during the initial semester for both decades and all scenarios, but unfavorable changes during the latter half of the year, primarily influenced by projected modifications in bottom salinity and bottom temperature. Conversely, for S. agassizii, P. brevirostris, and P. californiensis, predominantly negative changes surfaced across all months, decades, and scenarios, primarily driven by precipitation. These changes pose both threats and opportunities to shrimp fisheries in the CPO. However, their effects are not uniform across space and time. Instead, they form a mosaic of complex interactions that merit careful consideration when seeking practical solutions. These findings hold potential utility for informed decision-making, climate change mitigation, and adaptive strategies within the context of shrimp fisheries management in the CPO.
Subject(s)
Climate Change , Fisheries , Penaeidae , Animals , Pacific Ocean , Colombia , Penaeidae/physiology , EcosystemABSTRACT
From December 2012 to June 2014, 796 Pacific guitarfish were caught in 183 fishing sets in northern Peru. Catch occurred in 86.3% of sets. Most individuals caught were mature with a bias toward males. The mean total length for females and males was 83.4 cm, and 91.1 cm, respectively. The capture per unit effort (CPUE) was 12.6 ± 3.4 guitarfish (km.12 h)-1. The length-weight relationships showed that this species presents a sexual dimorphism in growth. These results support the importance of Sechura Bay as a key area for this species. This study represents the first species-specific fishery data for the Pacific guitarfish.
Subject(s)
Fisheries , Animals , Peru , Male , Female , Body Size , Sex Characteristics , Skates, FishABSTRACT
Scientists increasingly draw on fishers' ecological knowledge (FEK) to gain a better understanding of fish biology and ecology, and inform options for fisheries management. We report on a study of FEK among fishers along the Lower Ucayali River in Peru, a region of exceptional productivity and diversity, which is also a major supplier of fish to the largest city in the Peruvian Amazon. Given a lack of available scientific information on stock status, we sought to identify temporal changes in the composition and size of exploited species by interviewing fishers from 18 communities who vary in years of fishing experience since the mid-1950s. We develop four FEK-based indicators to assess changes in the fish assemblage and compare findings with landings data. We find an intensification of fishing gear deployed over time and spatiotemporal shifts in the fish assemblage and reported declines in species weight, which point to a fishing-down process with declines across multiple species. This finding is reflected in a shifting baseline among our participants, whereby younger generations of fishers have different expectations regarding the distribution and size of species. Our study points to the importance of spillover effects from the nearby Pacaya-Samira National Reserve and community initiatives to support the regional fishery. Reference to fishers' knowledge also suggests that species decline is likely underreported in aggregated landings data. Despite the dynamism and diversity of Amazonian floodplain fisheries, simple FEK-based indicators can provide useful information for understanding fishing-induced changes in the fish assemblage. Fishers hold valuable knowledge for fishery management and conservation initiatives in the region.
Subject(s)
Fisheries , Fishes , Peru , Animals , Fishes/physiology , Humans , Conservation of Natural Resources/methods , Time Factors , RiversABSTRACT
Species are expected to migrate to higher latitudes as warming intensifies due to anthropogenic climate change since physiological mechanisms have been adapted to maximize fitness under specific temperatures. However, literature suggests that upwellings could act as thermal refugia under climate warming protecting marine ecosystem diversity. This research aimed to predict the effects of climate warming on commercial and non-commercial fish species reported in official Mexican documents (>200 species) based on their thermal niche to observe if upwellings can act as potential thermal refugia. Present (2000-2014) and Representative Concentration Pathway (6.0 and 8.5) scenarios (2040-2050 and 2090-2100) have been considered for this work. Current and future suitability patterns, species distribution, richness, and turnover were calculated using the minimum volume ellipsoids as algorithm. The results in this study highlight that beyond migration to higher latitudes, upwelling regions could protect marine fishes, although the mechanism differed between the innate characteristics of upwellings. Most modeled species (primarily tropical fishes) found refuge in the tropical upwelling in Northern Yucatan. However, the highest warming scenario overwhelmed this region. In contrast, the Baja California region lies within the Eastern Boundary Upwelling Systems. While the area experiences an increase in suitability, the northern regions have a higher upwelling intensity acting as environmental barriers for many tropical species. Conversely, in the southern regions where upwelling is weaker, species tend to congregate and persist even during elevated warming, according to the turnover analysis. These findings suggest that tropicalization in higher latitudes may not be as straightforward as previously assumed. Nevertheless, climate change affects numerous ecosystem features, such as trophic relationships, phenology, and other environmental variables not considered here. In addition, uncertainty still exists about the assumption of increasing intensity of upwelling systems.
Subject(s)
Climate Change , Fishes , Animals , Fishes/physiology , Refugium , Mexico , Ecosystem , Global Warming , TemperatureABSTRACT
The elucidation of energetic patterns in adult viviparous elasmobranchs and their offspring can contribute to understanding ecophysiological questions, such as maternal-fetal metabolism and group life-history traits. We characterized the energetic substrates in pregnant individuals and stages of offspring development in the freshwater stingray Potamotrygon amandae. Our results show that the energetic distribution of the yolk is composed of more lipids than proteins, whereas the inverse pattern is observed in the egg and uterus, proving the plasticity of the energy provision of the species. As a novelty, we describe that yolk/intestine transfer occurs in this species.
Subject(s)
Skates, Fish , Animals , Skates, Fish/metabolism , Skates, Fish/physiology , Female , Egg Yolk/chemistry , Viviparity, Nonmammalian , Energy Metabolism , Fresh Water , Pregnancy , Uterus/metabolismABSTRACT
The blue shark is a highly migratory species with a worldwide distribution, making it susceptible to multiple fishing fleets across the globe. In southern Brazil, it is an important target, comprising up to 40% of the total biomass landed by the commercial surface longline fleet. This study aims to contribute to a better understanding of how the species uses the region and to update its life-history information available for future assessments. Over five consecutive years (2018-2022) of landings and onboard monitoring, we gathered size data and vertebral samples to describe the species size composition in the region, as well as its seasonal and interannual variability and to update estimated life-history parameters. The results showed that southern Brazil is mainly inhabited by large juvenile males that arrive during winter (July-September) and stay until spring (October-December), when their frequency decreases. Small adult males are present throughout the year but in higher frequencies during summer. A small number of adult females are present with higher frequencies during spring and summer, which decreases during the austral autumn and winter. Some variability in the presence of each life stage was observed among years. The estimated life-history parameters were as follows: L∞: 255.02 cm fork length (FL), k: 0.20, L0:35.68 cm FL for males; L∞: 246.47 cm FL, k: 0.23, L0:36.77 cm FL for females; and L∞: 269.58 cm FL, k: 0.18, L0:36.19 cm FL for pooled sexes. However, the estimated values must be cautiously interpreted, as the obtained samples cannot be construed as representative of the entire harvested stock due to the lack of consistent presence of some life stages in the study region.
Subject(s)
Body Size , Seasons , Sharks , Animals , Sharks/growth & development , Brazil , Male , Female , Life History TraitsABSTRACT
Yellowfin tuna, Thunnus albacares, represents an important component of commercial and recreational fisheries in the Gulf of Mexico (GoM). We investigated the influence of environmental conditions on the spatiotemporal distribution of yellowfin tuna using fisheries' catch data spanning 2012-2019 within Mexican waters. We implemented hierarchical Bayesian regression models with spatial and temporal random effects and fixed effects of several environmental covariates to predict habitat suitability (HS) for the species. The best model included spatial and interannual anomalies of the absolute dynamic topography of the ocean surface (ADTSA and ADTIA, respectively), bottom depth, and a seasonal cyclical random effect. High catches occurred mainly towards anticyclonic features at bottom depths > 1000 m. The spatial extent of HS was higher in years with positive ADTIA, which implies more anticyclonic activity. The highest values of HS (> 0.7) generally occurred at positive ADTSA in oceanic waters of the central and northern GoM. However, high HS values (> 0.6) were observed in the southern GoM, in waters with cyclonic activity during summer. Our results highlight the importance of mesoscale features for the spatiotemporal distribution of yellowfin tunas and could help to develop dynamic fisheries management strategies in Mexico and the U.S. for this valuable resource.
Subject(s)
Ecosystem , Tuna , Animals , Gulf of Mexico , Bayes Theorem , Oceans and SeasABSTRACT
The short-tail yellownose skate, Zearaja brevicaudata, occurs off southern Brazil and along the Argentine continental shelf, including waters surrounding the Islas Malvinas and the upper slope, and is very frequently caught by trawl fisheries throughout its range. The age, growth, and maturity of Z. brevicaudata were investigated using 204 individuals collected by commercial fishing vessels from northern Argentina, between March 2016 and September 2019. Age was determined on a sample comprising vertebrae from 151 individuals, 60 males, ranging in size from 391 to 956 mm total length (TL), and 91 females, ranging in size from 324 to 1060 mm TL. Maximum ages determined for males and females were 22 and 29 years, respectively. A Bayesian framework was employed with a set of three candidate models to estimate growth parameters (von Bertalanffy, Gompertz, and Logistic). The von Bertalanffy model had the best fit, and the sexes showed undistinguishable growth parameters. For sexes combined, derived growth mean parameters (± S.D.) were L∞ = 1081 mm ± 64.34 mm, k = 0.09 ± 0.01 years-1, and L0 = 248 mm ± 23.52 mm. The age at maturity was estimated at 13.15 and 14.66 years for males and females, respectively.
Subject(s)
Skates, Fish , Animals , Skates, Fish/growth & development , Male , Female , Argentina , Life History Traits , Fisheries , Bayes Theorem , Brazil , Sexual Maturation , Body SizeABSTRACT
There is no information on the species associated with the mesophotic reefs of Banderas Bay, located in the central Mexican Pacific. This study analysed the reef fish assemblage from three depths (50, 60 and 70 m) in three sampling sites of the southern submarine canyon of the Bay: Los Arcos, Bajo de Emirio and Majahuitas. Several analyses were performed to test the hypothesis that there are important differences in fish abundance and species composition between sites and depths. Twenty-two species of bony fishes grouped in 14 families were recorded. PERMANOVA results showed that there were no significant differences in fish diversity parameters between sites, indicating a certain uniformity in their distribution. However, nine species were exclusive to one site and depth (five singleton species with only one individual recorded and four unique species recorded only once). On the other hand, there were significant differences between depths, mainly between 50 and 70 m. Diversity decreases with depth and species composition changes. SIMPER, Shade Plot and NMDS analysis show the most representative species at each depth, with at least half of the species (11) recorded only at 50 m and four species at the deeper levels (60 - 70 m). The observed assemblage includes several of the most caught species in the shallow water artisanal fishery, which is the most traditional and common type of fishery in the Bay. In addition, the Pomacanthuszonipectus (Cortés angelfish) is of particular interest, as it has a special protection status in the official Mexican standard (NOM-059-SEMARNAT, 2010) due to its use as an ornamental species in aquaria. We hypothesised that the mesophotic zone may serve as a refuge for these fishes, so we propose that the information obtained is an important basis for new research aimed at the sustainable management of fisheries in the area.
ABSTRACT
This study delves into the foraging ecology of the cookiecutter shark (Isistius brasiliensis) in the Saint Peter and Saint Paul Archipelago (SPSPA), assessing bite marks on pelagic fishes collected between March and September 2018. Examination of 200 individuals from five species revealed the shark's predilection for targeting adult fish, ensuring efficient removal of energy-rich tissue layers. However, a notable exception is Thunnus albacares, preyed on predominantly during its juvenile stage, possibly due to vertical spatial segregation. Recent bites were pervasive across species, with wahoo displaying a distinctive pattern. Cookiecutter shark bites predominantly targeted the lateral body portion (>55%) except for yellowfin tuna, which exhibited a preference for the ventral region (95%). The estimated length distribution suggests the SPSPA as a potential nursery area for cookiecutter sharks. Bite mark positions and frequencies may be linked to fish behavior, swimming velocity, and fishing gear strategy, highlighting the complex interplay in pelagic ecosystems.
Subject(s)
Feeding Behavior , Predatory Behavior , Sharks , Animals , Sharks/physiology , Atlantic OceanABSTRACT
BACKGROUND: Phylogenetic gaps of public databases of reference sequences are a major obstacle for comparative genomics and management of marine resources, particularly in the Global South, where economically important fisheries and conservation flagship species often lack closely-related references. We applied target-enrichment to obtain complete mitochondrial genomes of marine ichthyofauna from the Brazilian coast selected based on economic significance, conservation status and lack of phylogenetically-close references. These included sardines (Dorosomatidae, Alosidae), mackerels (Scombridae) croakers (Sciaenidae), groupers (Epinephelidae) and snappers (Lutjanidae). RESULTS: Custom baits were designed to enrich mitochondrial DNA across a broad phylogenetic range of fishes. Sequencing generated approximately 100k reads per sample, which were assembled in a total of 70 complete mitochondrial genomes and include fifty-two new additions to GenBank, including five species with no previous mitochondrial data. Departures from the typical gene content and order occurred in only three taxa and mostly involved tRNA gene duplications. Start-codons for all genes, except Cytochrome C Oxidase subunit I (COI), were consistently ATG, whilst a wide range of stop-codons deviated from the prevailing TAA. Phylogenetic analysis confirmed assembly accuracy and revealed signs of cryptic diversification within the Mullus genus. Lineage delimitation methods using Sardinella aurita and S. brasiliensis mitochondrial genomes support a single Operational Taxonomic Unit. CONCLUSIONS: Target enrichment was highly efficient, providing complete novel mitochondrial genomes with little sequencing effort. These sequences are deposited in public databases to enable subsequent studies in population genetics and adaptation of Latin American fish species and serve as a vital resource for conservation and management programs that rely on molecular data for species and genus-level identification.
Subject(s)
Genome, Mitochondrial , Perciformes , Animals , Phylogeny , Fisheries , Fishes/genetics , Perciformes/genetics , DNA, Mitochondrial/genetics , CodonABSTRACT
Overfishing constitutes a major threat affecting marine fish population worldwide, including mullet species that have been exploited by fisheries during the reproductive migration in temperate and tropical latitudes for millennia. In the present study, we investigated the relationship of fishing intensity of mullet Mugil liza during its reproductive migration and the abundance of their juveniles in an essential nursery ground for the species in the southwest Atlantic Ocean. To carry out this analysis, we used a 23-year standardized long-term time series (1997-2019) of monthly abundance of M. liza juveniles, local/regional (water temperature, salinity, water transparency and river discharge) and global (ENSO) environmental factors, along with compilations of fishing landing data for the species. Generalized Additive Models (GAM) revealed the negative effect of fishing adult populations on the abundance of juveniles when they reach the marine surf-zone and after recruiting into the estuary. Our results reinforce the importance of adequate conservation and fishery regulation policies to prevent the species' stock from collapsing.
Subject(s)
Ecosystem , Smegmamorpha , Animals , Fisheries , Brazil , Conservation of Natural Resources , Water , Smegmamorpha/physiologyABSTRACT
Marine litter is a growing environmental problem for which fisheries-sourced waste remains poorly understood. In Peru, there is an ongoing challenge of waste management from the small-scale fisheries fleet given the lack of facilities to receive the variety of debris produced by fishers, which includes hazardous wastes such as batteries. In this study, onboard solid waste production was monitored daily by land-based observers upon landing at the port of Salaverry, Peru, from March to September 2017. The analysed small-scale gillnet and longline fishing fleets produced annually an estimated 11,260 kg of solid waste. Of particular concern is the production of single use plastics (3427 kg) and batteries (861 kg) due to their potential long-lasting impacts on the environment and challenges related to their proper disposal. A management plan for solid waste has been developed for Salaverry; therefore, a subsequent assessment was conducted in 2021-2022 of the behaviours and perceptions of fishers regarding the implementation of this plan. Most fishers (96%) reported disposing of their waste on land, except organic waste which is disposed of at sea. While fishers in Salaverry have become more conscious of the issues surrounding at-sea waste disposal and have an interest in better segregating and managing their waste, there remains a need for improved waste management and recycling protocols and procedures at the port to make this possible.
Subject(s)
Refuse Disposal , Solid Waste , Fisheries , Peru , Hazardous Waste , Plastics , Waste ProductsABSTRACT
Seascape genomics gives insight into the geographic and environmental factors shaping local adaptations. It improves the understanding of the potential effects of climate change, which is relevant to provide the basis for the international management of fishery resources. The pink abalone (Haliotis corrugata) is distributed from California, United States to Baja California Sur, Mexico, exposed to a latitudinal environmental gradient in the California Current System. Management of the pink abalone contrasts between Mexico and the United States; Mexico has an active fishery organized in four administrative areas, while the United States has kept the fishery in permanent closure since 1996. However, the impact of environmental factors on genetic variation along the species distribution remains unknown, and understanding this relationship is crucial for effective spatial management strategies. This study aims to investigate the neutral and adaptive genomic structure of H. corrugata. A total of 203 samples from 13 locations were processed using ddRADseq, and covering the species' distribution. Overall, 2,231 neutral, nine potentially adaptive and three genomic-environmental association loci were detected. The neutral structure identified two groups: 1) California, United States and 2) Baja California Peninsula, México. In addition, the adaptive structure analysis also detected two groups with genetic divergence observed at Punta Eugenia. Notably, the seawater temperature significantly correlated with the northern group (temperate) and the southern (warmer) group. This study is a valuable foundation for future research and conservation initiatives, emphasizing the importance of considering neutral and adaptive genetic factors when developing management strategies for marine species.
Subject(s)
Gastropoda , Animals , Mexico , Genomics , Genetic Drift , SeawaterABSTRACT
Growing fish in a recirculating aquaculture system (RAS) involves various stress factors that directly affect their physiological condition. This study aimed to investigate the effect of a chelated organic-mineral additive including Fe, Mn, Cu, Zn, Co, Se and I; on the rearing performance of juvenilecatfish (Clariasgariepinus) under RAS conditions. Four groups of fish (n=50) were formed: a control group (receiving standard feed) and three experimental groups (receiving standard feed with biogenic elements chelate compounds in different concentrations). At the end of the experiment (30 days), the physiological condition of the fish was evaluated by the growth rate, internal organs condition, blood serum biochemical indices and histological examination of the middle intestine. The survival rate of fish in the experimental groups was 96-98%. According to the results, the absolute increase was 14,30% in group III, 11,13% in group II and 6,71% in group I, compared to the control. However, the use of chelated compounds in high concentrations can cause necrosis and erosion of the apical part of the villi (groups II and III). Blood biochemical analysis of fish (group II and III) receiving medium and high concentrations of chelated compounds showed high ALT activity, which was 23,02% (p<0,05) and 45,19% (p<0,05) higher compared to control, respectively. Mineral-chelate compounds, of the studied composition, at a concentration of 0,5 g/kg positively affect the histological structure of the midgut of Clarias gariepinus. This dosage of the investigated feed additive can be recommended for the practical application of rearing Clariasgariepinus in closed water installations.
Este estudo teve como objetivo investigar o efeito de um aditivo orgânico-mineral quelatado que inclui Fe, Mn, Cu, Zn, Co, Se e I sobre o desempenho de criação de juvenis de bagre-africano (Clarias gariepinus) em condições de RAS. Foram formados quatro grupos de peixes (n=50): um grupo controle (recebendo ração padrão) e três grupos experimentais (recebendo ração padrão com elementos biogênicos compostos quelatos em diferentes concentrações). Ao final do experimento (30 dias), a condição fisiológica dos peixes foi avaliada pela taxa de crescimento, condição dos órgãos internos, índices bioquímicos séricos sanguíneos e exame histológico do intestino médio. A taxa de sobrevivência dos peixes nos grupos experimentais foi de 96-98%. De acordo com os resultados, o aumento absoluto foi de 14,30% no grupo III, 11,13% no grupo II e 6,71% no grupo I, em relação ao controle. No entanto, o uso de compostos quelatados em altas concentrações pode causar necrose e erosão da parte apical das vilosidades (grupos II e III). A análise bioquímica do sangue de peixes (grupo II e III) que receberam concentrações médias e altas de compostos quelatados mostrou alta atividade de ALT, que foi 23,02% (p<0,05) e 45,19% (p<0,05) maior comparado ao controle, respectivamente. Compostos mineral-quelatos, da composição estudada, na concentração de 0,5 g/kg, afetam positivamente a estrutura histológica do intestino médio de Clarias gariepinus. Esta dosagem do aditivo alimentar investigado pode ser recomendada para a aplicação prática de criação de Clarias gariepinus em instalações de água fechadas.
Subject(s)
Animals , Catfishes/growth & development , Aquaculture , Fisheries , Food AdditivesABSTRACT
Many countries have encountered coronavirus pandemic crisis around the world. Through the outbreak of this disease in Iran, preventive plans have been implemented to break the chain of the disease infection. These measures in the economic sector have affected supply, production and demand, and to some extent have led to the partial or complete closure of some businesses and occupations. In the context, it seems that innovative an "innovation capacity" infrastructure measures and turning to innovation in this crisis can be a strategy to moderate and optimize the situation. This study tries to design concepts of the fisheries firms' innovation capacity model in the context of the COVID-19 pandemic crisis. After collecting data, they were analyzed using SPSS and PLS SMART software, which were performed in two parts: descriptive statistics and analytical or inferential statistics. A novel research model is presented to examine the impact of factors such as innovation management, social, cultural, human and organizational capital, crisis strategies, government actions in crisis situations, and marketing strategies in crisis situations, as well as, recognition and application of marketing advantages in crisis situations, which offers a re-analysis of innovation capacity. According to the results, among the variables played a significant role on the level of innovation capacity in epidemic conditions, innovation management (p> 0.000; ß = 0.593), and recognition and application of marketing advantages (p> 0.049; ß = 0.209) were the most significant, independent variables affecting the innovation capacity, which explained its variations.
Muitos países enfrentaram crises na pandemia de coronavírus em todo o mundo. Por meio do surto dessa doença no Irã, planos preventivos foram implementados para quebrar a cadeia de infecção da doença. Essas medidas no setor econômico afetaram a oferta, a produção e a demanda e, em certa medida, levaram ao fechamento parcial ou total de alguns negócios e serviços. Nesse contexto, parece que medidas de infraestrutura inovadoras e com "capacidade de inovação" podem ser uma estratégia para moderar e otimizar a situação nesta crise. Este estudo tenta desenhar conceitos do modelo de capacidade de inovação das empresas de pesca no contexto da crise da pandemia de COVID-19. Após a coleta dos dados, eles foram analisados ââpor meio dos softwares SPSS e PLS SMART e realizados em duas partes: estatística descritiva e estatística analítica ou inferencial. Um novo modelo de pesquisa é apresentado para examinar o impacto de fatores como gestão da inovação, capital social, cultural, humano e organizacional, estratégias de crise, ações governamentais em situações de crise e estratégias de marketing em situações de crise, bem como reconhecimento e aplicação de vantagens de marketing em situações de crise, que oferece uma reanálise da capacidade de inovação. De acordo com os resultados, entre as variáveis ââque desempenharam um papel significativo no nível de capacidade de inovação em condições epidêmicas, a gestão da inovação (p > 0,000; ß = 0,593) e o reconhecimento e aplicação de vantagens de marketing (p > 0,049; ß = 0,209) foram as variáveis ââindependentes mais significativas que afetaram a capacidade de inovação, o que explicou suas variações.
Subject(s)
Organization and Administration , Coronavirus , Marketing , Economics , PandemicsABSTRACT
Introduction: Until today, the fishing effort by foreign fleets in the Costa Rican Pacific has not been analyzed. Objective: To determine the spatial distribution of the fishing effort of those fleets, variables that shape that distribution, and if they interact with management figures and highly fragile ecosystems. Methods: Using fishing effort data from 2012 to 2020, obtained from Global Fishing Watch, an Index of Fishing Effort (IEP) was calculated to apply geospatial and multivariate statistics, as well as multiple regression models. A grid with 55 905 cells of 0.10 degrees was used to apply Hot Spot Analysis, and another grid with 24 176 cell-year-month analysis units of 0.25 degrees was used to apply a Linear Regression Model. Results: The data reveals the fishing activity of international fleets associated with four types of fishing gear, and a wide coverage of a high IEP by two fleets throughout the nine years analyzed. The IEP is primarily associated with location and varies by month and year. There is also relative evidence that its influenced by the concentration of oxygen and nitrates. Conclusions: International fleets come into direct conflict with officially defined zones for national fleets and disrespect protected oceanic areas and a declared non-fishing zone to protect marine resources in the Costa Rican Pacific. Their activities in the Dome may affect a national yellowfin tuna fishery.
Introducción: Hasta hoy, no ha sido analizado el esfuerzo pesquero por parte de flotas extranjeras en el Pacífico de Costa Rica. Objetivo: Determinar la distribución espacial del esfuerzo pesquero de esas flotas, variables que moldean esa distribución, y si las mismas interactúan con figuras de manejo y ecosistemas altamente frágiles. Métodos: A partir de datos de esfuerzo pesquero de 2012 a 2020, obtenidos de Global Fishing Watch, fue calculado un Índice de Esfuerzo Pesquero (IEP) sobre el cual fue aplicada estadística geoespacial y multivariada, así como modelos de regresión múltiple. Fue utilizada una cuadrícula con 55 905 celdas de 0.10 grados, para aplicar Análisis de Puntos Calientes, y otra cuadrícula con 24 176 unidades de análisis celdas-año-mes de 0.25 grados, para aplicar un Modelo de Regresión Lineal. Resultados: Los datos revelan la actividad pesquera de las flotas internacionales asociadas a cuatro tipos de artes de pesca, así como una amplia cobertura de alto IEP por parte de dos flotas a lo largo de los nueve años analizados. El IEP se asocia principalmente con la ubicación y varía según el mes y el año. También hay evidencia relativa de que está influenciado por la concentración de oxígeno y nitratos. Conclusiones: Las flotas internacionales entran en conflicto directo con zonas oficialmente delimitadas para las flotas nacionales e irrespetan las áreas oceánicas protegidas y una zona no pesquera declarada para proteger los recursos marinos en el Pacífico costarricense. Sus actividades en el Domo pueden afectar la pesquería de atún aleta amarilla.
Subject(s)
Animals , Marine Conservation Area , Fisheries/statistics & numerical data , Fishing Industry , Costa RicaABSTRACT
Although much in the lives of members of the Caiçara small-scale fishing communities of Lázaro and Saco da Ribeira in Ubatuba, southeastern Brazil would suggest hardship, that population expresses a surprising degree of satisfaction with life. In this paper, we use a social wellbeing lens as applied through an ethnographic, mixed methods approach to reflect on this overall sense that lives rooted in small-scale fishing are well worth living despite their many challenges. We see the classic maritime anthropology theme of identity at the heart of meaning and life satisfaction. Identity provides core aspects of how people engage with their realities and anchors values that are reference points in work and social relations. With reference to the relational nuances revealed by the social wellbeing perspective, however, we show that Caiçara and small-scale fishing identities are not monolithic, but reflect gender and other social positions, and personal and familial experiences. These experiences include grappling with the complex effects of economic, social, political, and environmental changes. We conclude by arguing that fisheries policy that seeks to prioritize human wellbeing would benefit by adopting a social wellbeing perspective. Fisheries policy could thereby take into account identity, values, and relational elements of social life that give meaning and a sense of belonging to small-scale fishers, while also recognizing the cross-cutting and often contradictory variations in human experience that arise from social and economic differences. This social fabric of small-scale fishers' lives shapes their intentions and actions and is thus a necessary complication to the practice of fisheries management that its proponents need to consider.