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Abstract Pakistan is an agricultural country and fisheries play a very important role in the economic development of the country. Different diseases are prevalent in Pakistani fish but information related to the causative agents is not well-known. Keeping in view the significance of bacterial pathogens as the causative agents of multiple fish diseases, the present study was conducted for identification, characterization and analysis of virulence genes of Aeromonas spp. isolated from diseased fishes. A total of fifty fish samples having multiple clinical indications were collected from different fish farms of district Kasur, Punjab Pakistan. For isolation of Aeromonas spp. samples were enriched and inoculated on Aeromonas isolation medium. Isolates were identified and characterized by different biochemical tests, Analytical Profile Index (API) 20E kit and Polymerase Chain Reaction (PCR) assays. All isolates were screened for three putative virulence genes including aerolysin (aer), haemolysin (hyl) and heat labile cytotonic enterotoxin (alt). Seven isolates of Aeromonas (A.) hydrophila were retrieved and identified based on API 20E. These isolates were further confirmed as A. hydrophila on the basis of PCR assays. Three isolates were detected positive for the presence of virulence genes (alt and hyl). Whereas aerolysin (aer) gene was not present in any of A. hydrophila isolates. The present study confirmed A. hydrophila as the causative agent of epizootic ulcerative syndrome and motile Aeromonas septicemia in fish farms of district Kasur, Punjab Pakistan. Moreover, detection of two virulence genes (alt and hyl) in A. hydrophila isolates is a threat for fish consumers of study area. Resumo O Paquistão é um país agrícola, onde a pesca desempenha um papel muito importante para o desenvolvimento econômico. Diferentes doenças são prevalentes em peixes do Paquistão, mas as informações relacionadas aos agentes causadores não são bem conhecidas. Tendo em vista a importância dos patógenos bacterianos como agentes causadores de múltiplas doenças em peixes, o presente estudo foi conduzido para identificação, caracterização e análise de genes de virulência de isolados de Aeromonas spp. de peixes doentes. Foram coletadas 50 amostras de peixes com múltiplas indicações clínicas em diferentes fazendas do distrito de Kasur, Punjab, Paquistão. Para isolar Aeromonas spp., as amostras foram enriquecidas e inoculadas em meio de isolamento. Os isolados foram identificados e caracterizados por diferentes testes bioquímicos, kit Analytical Profile Index (API) 20E, e ensaios de reação em cadeia da polimerase (PCR). Todos os isolados foram selecionados para três genes de virulência putativos, incluindo aerolisina (aer), hemolisina (hyl) e enterotoxina citotônica termolábil (alt). Sete isolados de Aeromonas hydrophila foram recuperados e identificados com base no API 20E. Esses isolados foram posteriormente confirmados como A. hydrophila de acordo com ensaios de PCR. Três isolados indicaram a presença de genes de virulência (alt e hyl), enquanto o gene aerolisina (aer) não esteve presente em nenhum dos isolados de A. hydrophila. O presente estudo confirmou A. hydrophila como o agente causador da síndrome ulcerativa epizoótica e septicemia móvel por Aeromonas em fazendas de peixes, no distrito de Kasur, Punjab, Paquistão. Além disso, a detecção de dois genes de virulência (alt e hyl) em isolados de A. hydrophila é uma ameaça para os consumidores de peixes da área de estudo.

Coastal nature-based solutions (NbS) are increasingly recognized for their multiple benefits to socio-ecological systems, including climate mitigation and adaptation (e.g. conservation, restoration and sustainable management of coastal ecosystems for climate). National climate plans, such as the Nationally Determined Contributions (NDCs) developed under the Paris Agreement, include coastal NbS as a practical and effective action to help countries achieve their climate and biodiversity targets. However, the absence of a standardized NDC structure and the lack of guidance about how NbS should be included in NDCs can hinder access to external funding for developing countries and prevent transparent reporting on progress at the international level. In this context, our aim is to understand how coastal NbS are currently included in NDCs by evaluating their alignment with the IUCN Global Standard for NbS. Our analysis focuses on the description of coastal NbS in the NDCs of Pacific Small Island Developing States (PSIDS), as they are among the most vulnerable countries to the impacts of climate change. Overall, we find that, for the 22 coastal NbS examined in the NDCs of PSIDS, the degree of alignment with the eight criteria of the IUCN Global Standard is insufficient or partial, with slightly better alignment with the standard in revised NDCs than in original NDCs. We discuss opportunities provided by the standardization of the description of coastal NbS in NDCs, in terms of access to funding and stock taking to monitor the effectiveness of implementation and progress towards long-term goals. We also discuss the relevance of using the IUCN Global Standard for reporting on NbS in NDCs for PSIDS.

AbstractArchival (data-storage) and telemetry (acoustic and radio) tags are commonly used to provide data on the behavior and physiology of organisms, as well as data on their surrounding environment. For fishes, it is often advantageous to implant tags in the peritoneal cavity (i.e., intracoelomic implantation). The literature on best practices is limited for marine species, and near absent for tunas despite their regular application. We identify recommended practices using laparotomy in tropical tuna species following observations from thousands of tags implantations undertaken during implementation of several tagging programs across the Pacific. These recommended practices include descriptions of preferred tagging stations and equipment, fish selection, surgical procedures, and return of the fish to the wild. While these recommended practices were developed specifically for tropical tuna species, they are also likely applicable for other pelagic fishes. We present these guidelines to guide and promote the development of best practices for such procedures on pelagic species.

Ocean acidification (OA) has been identified as one of the major climate-change related threats, mainly due to its significant impacts on marine calcifiers. Among those are the calcareous green algae of the genus Halimeda that are known to be major carbonate producers in shallow tropical and subtropical seas. Hence, any negative OA impacts on these organisms may translate into significant declines in regional and global carbonate production. In this study, we compiled the available information regarding Halimeda spp. responses to OA (experimental, in situ), with special focus on the calcification responses, one of the most studied response parameters in this group. Furthermore, among the compiled studies (n = 31), we selected those reporting quantitative data of OA effects on algal net calcification in an attempt to identify potential general patterns of species- and/or regional-specific OA responses and hence, impacts on carbonate production. While obtaining general patterns was largely hampered by the often scarce number of studies on individual species and/or regions, the currently available information indicates species-specific susceptibility to OA, seemingly unrelated to evolutionary lineages (and associated differences in morphology), that is often accompanied by differences in a species� response across different regions. Thus, for projections of future declines in Halimeda-associated carbonate production, we used available regional reports of species-specific carbonate production in conjunction with experimental OA responses for the respective species and regions. Based on the available information, declines can be expected worldwide, though some regions harbouring more sensitive species might be more impacted than others.

International audience; Hemocytes are the circulating cells of the hemolymph of oysters and are responsible for numerous physiologicalfunctions, including immune defense. The oyster Crassostrea gasar is a native species inhabiting mangrove habitatand is of great commercial interest, cultured throughout the Brazilian coast, mainly in the north and northeast.Despite its commercial importance, little is known about its immunological aspects and defense cells, the hemocytes.This work aimed to morphologically characterize hemocytes of the oyster C. gasar and to study one ofthe main cellular defense response, phagocytosis, using light microscopy and flow cytometry. The results showedthe presence of six hemocyte populations in C. gasar hemolymph. These comprise of large and small granulocytes,large and small hyalinocytes, blast-like cells and a rare type classified as vesicular or serous hemocytes.Hyalinocytes were highly abundant and the most heterogeneous cell population, while small granulocytes, alongwith vesicular hemocytes were the less abundant population. Hemocytes of C. gasar oysters demonstrated capabilitiesto phagocytose three different types of particles tested: zymosan A, latex particles and Escherichia coli,indicating a broad defense capacity. The zymosan A were the most engulfed particles, followed by beads, mainlyphagocytized by granulocytes, the most phagocytic cells, and finally E. coli, which were the least phagocytized.This study is the first characterization of C. gasar oyster hemocytes and will support future studies that aim tounderstand the participation of different hemocyte types in defense responses against pathogens and/or environmentalchanges.

Resumen: La explotación de los recursos costero-marinos en nuestras costas ha ocurrido desde hace unos 12 000 años; esta actividad ha sido intensa y con menosprecio por el estado del recurso que se explota; como consecuencia, muchos de los recursos han colapsado a través de los siglos: las perlas, el carey, la madreperla, las tortugas, las chuchecas y muchas otras especies han dejado de ser comercialmente viables. Actualmente, los recursos pesqueros, que antes se creían inagotables, también muestran señales inequívocas de sobreexplotación. Lejos de haber mejorado nuestra relación con los recursos marinos ha empeorado; el aumento de la explotación, combinada con la contaminación y el calentamiento de nuestros mares, los ha deteriorado. Los imprescindibles análisis de biomasa y estado de las poblaciones explotadas siguieron sin realizarse, aún después de la fundación del INCOPESCA en 1994. Los desembarcos totales, entre 2000 y 2015, disminuyeron en un 45 % y la flota artesanal ha sido la más golpeada. Las embarcaciones pesqueras han pasado de 5 000 en el 2010 a menos de 2 000 cuatro años después y el número de empleos en el sector ha disminuido en un 50 %. Es urgente que tengamos una institucionalidad capaz de generar información que permita determinar el nivel y la forma de explotación adecuados. Este manejo debe ser independiente de intereses económicos y políticos y debe venir acompañado de una administración eficiente y efectiva, así como de un control y vigilancia estrictos de la actividad. Abstract: The exploitation of coastal-marine resources has occurred in our coasts since about 12 000 years ago. This activity has been intense and careless regarding to the well-being of the resource being exploited. Consequently, many of the resources have collapsed throughout the centuries. Pearls, tortoiseshell, mother-of-pearl, turtles, mangrove-cockle, and many other species have stopped being commercially viable. Presently, fisheries, formerly believed inexhaustible, also show unequivocal signs of overexploitation. Far from improving, our relationship with marine resources has exacerbated. The exploitation increment, combined with contamination and ocean warming, have deteriorated these resources. Essential biomass and population status analyses continue to be neglected, even after the founding of INCOPESCA in 1994. Total ship landings, between 2000-2015 have decreased 45 % impacting particularly the artisanal fleet. The number of fishing vessels have gone from 5 000 in 2010 to less than 2 000 four years later and the number of jobs in the sector has decreased by 50 %. It is urgent to have an institution able to generate information that allow us to determine the level and manner of this exploitation. Such management needs to be independent of economic and political interests and should be coupled with an efficient and effective administration, together with strict control and surveillance of this activity.

Abstract Background: Biological invasions threaten the functioning of ecosystems, biodiversity, and human well-being by degrading ecosystem services and eliciting massive economic costs. The European Union, as the world’s third-largest economy, has historically been a hub for cultural development and global trade, and thus, has extensive opportunities for the introduction and spread of alien species. While reported costs of biological invasions to some member states have been recently assessed, ongoing knowledge gaps in taxonomic and spatio-temporal data suggest that these costs were considerably underestimated. Results: We used the latest available cost data in InvaCost (v4.1) — the most comprehensive database on the costs of biological invasions — to assess the magnitude of this underestimation within the European Union via projections of current and future invasion costs. We used macroeconomic scaling and temporal modelling approaches to project available cost information over gaps in taxa, space, and time, thereby producing a more complete estimate for the European Union economy. We identified that 259 out of 13,331 (~ 1%) of known invasive alien species have reported costs in the European Union. Using a conservative subset of highly reliable, observed, country-level cost entries from 49 species (totalling US$4.7 billion; 2017 value) and information on ~ 13,000 established alien species within European Union member states, we projected unreported cost data for all member states. Conclusions: Our corrected estimate of observed costs was potentially 501% higher (US$28.0 billion) than currently recorded. Using future projections of current estimates, we also identified a substantial increase in costs and costly species (US$148.2 billion) by 2040. We urge for improved cost reporting to clarify economic impacts of greatest concern, concomitant with coordinated international action to prevent and mitigate the impacts of invasive alien species in the European Union and globally.

AbstractFires in Africa account for more than half of global fire-carbon emissions but the long-term evolution of fire activity and its link to global climate change remains elusive. Paleofire records provide descriptive information about fire changes through time, going beyond the range of satellite observations, although fire regime characteristics are challenging to reconstruct. To address this conceptual gap, we report here the abundance and morphometric data for a large set of microscopic charcoal samples (n = 128) recovered from surface ocean sediments offshore Africa. We show that in subtropical Southern Africa, large and intense fires prevailing in open savanna-grassland ecosystems produce a high abundance of small and elongated microcharcoal particles. In contrast, in the forest ecosystems of equatorial and tropical regions of western and central Africa, low-intensity fires dominate, producing low amounts of squared microcharcoal particles. Microcharcoal concentration and morphotype in marine sediment records off Africa are thus indicative of fire regime characteristics. Applied to down-core marine charcoal records, these findings reveal that at orbital time-scale intense and large, open grassland-savanna fires occurred during wet periods in the sub-tropical areas. A strong contribution of fire carbon emissions during periods of precession and summer insolation maxima in the geological record is thus expected.

Despite the importance of marine megafauna on ecosystem functioning, their contribution to the oceanic carbon cycle is still poorly known. Here, we explored the role of baleen whales in the biological carbon pump across the southern hemisphere based on the historical and forecasted abundance of five baleen whale species. We modelled whale-mediated carbon sequestration through the sinking of their carcasses after natural death. We provide the first temporal dynamics of this carbon pump from 1890 to 2100, considering both the effects of exploitation and climate change on whale populations. We reveal that at their pre-exploitation abundance, the five species of southern whales could sequester 4.0 × 10 5 tonnes of carbon per year (tC yr −1 ). This estimate dropped to 0.6 × 10 5 tC yr −1 by 1972 following commercial whaling. However, with the projected restoration of whale populations under a RCP8.5 climate scenario, the sequestration would reach 1.7 × 10 5 tC yr −1 by 2100, while without climate change, recovered whale populations could sequester nearly twice as much (3.2 × 10 5 tC yr −1 ) by 2100. This highlights the persistence of whaling damages on whale populations and associated services as well as the predicted harmful impacts of climate change on whale ecosystem services.