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Increasing sea temperature is a driver of change for many fish traits, particularly for fast-growing epipelagic species with short life spans. With warming, altered spawning phenology and faster growth may produce substantially larger body sizes of the new cohort, affecting fishery productivity. We present an individual-based model (IBM) that predicts the distribution of fish length at catch under observed and projected thermal scenarios, accounting for mortality, temperature-dependent spawning phenology, temperature- and photoperiod- dependent growth. This IBM was demonstrated with Coryphaena hippurus (common dolphinfish), a circumglobally-distributed and highly thermophilic species sustaining commercial and recreational fisheries where it is present. The model projected a 13.2% increase in the average length at catch under marine heatwave conditions compared to the current thermal regime (1995–2005 average). Projections under RCP scenarios 4.5 and 8.5 by the end of the century led to 5.1% and 12.8% increase in average length, respectively. Furthermore, these thermal scenarios affected spawning phenology differently, producing higher variance in body size under RCP 8.5 scenario with respect to marine heatwave conditions. This study highlights how the environmental effects of climate change can alter the distribution of species length at catch., The present paper is part of the CERES project (H2020, EU 678193). Part of the data was obtained from the FAO-Copemed and FAO-Copemed II projects (http://www.faocopemed.org/). This study has been conducted using E.U. Copernicus Marine Service Information. V. Moltó acknowledges a predoctoral grant funded by the Regional Government of the Balearic Islands and the European Social Fund, A. Ospina Álvarez was supported by H2020 Marie Skłodowska-Curie Actions (746361), and S. Pérez-Mayol salary was founded by PN Project DREAMER (CTM2015-66676-C2-1-R). We also acknowledge Andreina Fenech, Marie Louise Pace, and Roberta Mifsud from the Department of Fisheries and Aquaculture of Malta for the data collection and provision.

Pop-up satellite archival tags (PSATs) have been used to demonstrate habitat utilization and large-scale migrations of aquatic species and are a critical tool to manage highly migratory fish populations. Use of PSATs has increased in recent years; however, few studies have investigated the physiological and behavioral effects of carrying a PSAT. To address this gap, young-adult mahi-mahi (Coryphaena hippurus; 25–35 cm fork length) were tagged with miniature PSATs and assessed in a two-part experiment utilizing swim tunnel respirometry and behavioral analysis of free-swimming individuals. Swim tunnel respirometry revealed significant reductions in the critical and optimal swimming speeds of tagged fish (10.2% and 20.9%, respectively), as well as significant reductions in maximum metabolic rate and aerobic scope (16.1% and 21.4%, respectively). In contrast, mean and maximum velocity, acceleration, total distance traveled, survival, and feeding success of free-swimming tagged fish showed no impacts of tagging compared with untagged conspecifics held in the same tank. The results of this study highlight the importance of considering multiple methodologies to assess the impacts of tagging fish and provide insight into the data collected by PSATs deployed on wild fish.

Mahi-mahi (Coryphaena hippurus) are photopic predators that rely on vision for predator avoidance and foraging behavior. Research conducted on Mahi-mahi vision has been primarily focused on adults,...

Mercury is a trace element that is potentially dangerous due its high toxicity and tendency to bioaccumulate in organisms. Currently, high mercury concentrations are seen in the environment especially due climate changes. Studies regarding mercury bioavailability in the southwestern Atlantic Ocean using tuna and tuna-like species are rare. The aim of the present study was to use tuna and tuna-like species (Thunnus atlanticus, Thunnus albacares, Katsuwonus pelamis, Euthynnus alletteratus, Coryphaena hippurus and Sarda sarda) as indicators of the availability of total mercury (THg) in oceanic food webs of the southwestern Atlantic Ocean. THg concentrations varied significantly among species for both muscle and liver (Kruskal–Wallis test; H5,130 = 52.7; p

Deepwater Horizon crude oil is comprised of polycyclic aromatic hydrocarbons that cause a number of cardiotoxic effects in marine fishes across all levels of biological organization and at different life stages. Although cardiotoxic impacts have been widely reported, the mechanisms underlying these impairments in adult fish remain understudied. In this study, we examined the impacts of crude oil on cardiomyocyte contractility and electrophysiological parameters in freshly isolated ventricular cardiomyocytes from adult mahi-mahi (Coryphaena hippurus). Cardiomyocytes directly exposed to oil exhibited reduced contractility over a range of environmentally relevant concentrations (2.8-12.9 μg l-1∑PAH). This reduction in contractility was most pronounced at higher stimulation frequencies, corresponding to the upper limits of previously measured in situ mahi heart rates. To better understand the mechanisms underlying impaired contractile function, electrophysiological studies were performed, which revealed oil exposure prolonged cardiomyocyte action potentials and disrupted potassium cycling (9.9-30.4 μg l-1∑PAH). This study is the first to measure cellular contractility in oil-exposed cardiomyocytes from a pelagic fish. Results from this study contribute to previously observed impairments to heart function and whole-animal exercise performance in mahi, underscoring the advantages of using an integrative approach in examining mechanisms of oil-induced cardiotoxicity in marine fish.

To gauge the effectiveness of supplementing native populations of dolphinfish Coryphaena hippurus, we compared farm-raised and wild fish in terms of their horizontal and vertical movement patterns, habitat preferences and thermal niche using pop-up satellite archival tags (PSATs) deployed in two disparate locations: the sub-tropical southeastern coast of Taiwan (wild, n = 4), and temperate Kagoshima Bay, Japan (farm-raised, n = 3). Tagged fish were tracked for periods of 7–40 days, reached depths > 100 m, and experienced temperatures of 15–30 °C in Taiwan, and 20–23 °C in Kagoshima Bay. Fish tagged in Taiwan made primarily northward movements during early summer but changed to a southward course in early winter. In Kagoshima Bay, tagged fish undertook southward excursions along the coast and movements were confined to the bay. Dolphinfish spent > 50% of their time near the surface and made more extensive vertical movements during the night than during the day; vertical movements were largely confined to the mixed layer. Depth distributions appeared to be limited by a Δ6 °C change in temperature relative to sea surface temperature (i.e., > 90% of movements were within 6 °C of the warmest water available).

Identifying complex behaviors such as spawning and fine-scale activity is extremely challenging in highly migratory fish species and is becoming increasingly critical knowledge for fisheries management in a warming ocean. Habitat use and migratory pathways have been extensively studied in marine animals using pop-up satellite archival tags (PSATs), but high-frequency data collected on the reproductive and swimming behaviors of marine fishes has been limited by the inability to remotely transmit these large datasets. Here, we present the first application of remotely transmitted acceleration data to predict spawning and discover drivers of high activity in a wild and highly migratory pelagic fish, the mahi-mahi (Coryphaena hippurus). Spawning events were predicted to occur at nighttime, at a depth distinct from non-spawning periods, primarily between 27.5 and 30°C, and chiefly at the new moon phase in the lunar cycle. Moreover, throughout their large-scale migrations, mahi-mahi exhibited behavioral thermoregulation to remain largely between 27 and 28°C and reduced their relative activity at higher temperatures. These results show that unveiling fine-scale activity patterns are necessary to grasp the ecology of highly mobile species. Further, our study demonstrates that critical, and new, ecological information can be extracted from PSATs, greatly expanding their potential to study the reproductive behavior and population connectivity in highly migratory fishes.

The anthropogenic impact of pollution by plastic debris has threatened marine life inhabiting benthic and pelagic habitats from the poles to the equa tor (e.g., Ryan and Moloney, 1993; Derraik, 2002; Thompson et al., 2004). The ingestion of plastics by marine organisms is an increasing global trend due to the increase of these polymers in the oceans (e.g., Lusher et al., 2013; Besseling et al., 2015; Lusher et al., 2015; Lusher et al., 2018; Ostle et al., 2019; Neto et al., 2020). After reaching marine ecosystems, plas tics can be found either in their large original size (i.e., macroplastic) or in small fragments (i.e., nanoplastics, microplastics, or mesoplastics) (Azevedo-Santos et al., 2019). Thus, the interaction of plastic debris with marine life is expected, and their ingestion has been documented in a wide range of marine organisms, including zooplankton, bivalves, fish, turtles, birds, and marine mammals (Azzarello and Van-Vleet, 1987; Lusher et al., 2015; Romero et al., 2015; Egbeocha et al., 2018). There are several possible reasons for the consumption of plastic debris by marine fish, includ ing mistaking plastic for food because the odor of plastic in the sea is like that of food (Savoca et al., 2017), confusing it with prey species associated with floating plastic material while feeding on them, and preying on smaller organisms that have previously ingested plastics (Possato et al., 2011; Varghese et al., 2013 Institute of Oceanography of the University of Sao Paulo (IOUSP) Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior (CAPES):7,546/13-0 info:eu-repo/semantics/publishedVersion

The present study aims to assess the diet composition of five commercial pelagic fishes caught in aggregated schools in the western Atlantic, quantify plastic and anthropogenic items in stomach contents, and analyze the possible relationship between their diet composition and the occurrence of anthropogenic items. We collected 807 stomachs from tunas (Thunnus albacares, Thunnus obesus, and Katsuwonus pelamis) and tuna-like species (Coryphaena hippurus and Elagatis bipinnulata) targeted by fisheries around data buoys in the western tropical Atlantic between 2011 and 2017. We quantified items of an anthropogenic origin by calculating frequency of occurrence. Feeding strategy was determined using a 3D scatterplot. Correspondence analysis (CA) was performed to determine the relationship between food items and the occurrence of anthropogenic materials (synthetic or organic). Fishing ropes and chum were the main items of an anthropogenic origin. Rainbow runner (E. bipinnulata) stomachs had the highest percentage of such items, whereas none were found in the bigeye tuna. The most affected species by anthropogenic items feed on epipelagic prey items, such as flying fishes. Organisms that aggregate around floating objects on the ocean surface and have a generalist diet are more likely to ingest synthetic items either accidently or actively. The present findings underscore the importance of environmental education programs to mitigate the impact of marine debris on organisms and ensure the health of individuals as well as the balance of the food web to which these species belong.

Background The dolphinfish, Coryphaena hippurus, is a fast-swimming, predatory fish exhibiting relatively fast growth and early maturation among marine teleosts. It is an important, potentially renewable resource throughout its global subtropical-to-tropical range. Understanding the ecology of this wide-ranging fish is critical to proper fisheries management, but studies have historically depended heavily upon aggregated catch data reported by fisheries. This study uses tagging data to explore finer scale dolphinfish movements in two subregions of the Eastern Pacific Ocean (EPO)—the west coasts of Baja California Peninsula (WBC) and Oaxaca (OAX), Mexico. Results Adult dolphinfish (fork length 66–129 cm) were tagged with conventional (n = 132 tags) and electronic tags (n = 30 tags, miniPAT) between 2010 and 2014. Recapture rate of conventional tags was 4.5% with a maximum days of liberty of 141 days (mean = 56 d); 20 electronic tags reported but all did so prior to programmed release dates, with days at liberty ranging from 4 to 62 (mean = 24 d). Fish remained within the region they were tagged except for six fish tagged in WBC and one in OAX. Latitudinal (WBC) and longitudinal (OAX) extensions of observed fish movements (determined via a novel analytical approach) increased with days at liberty. Despite occasional deep dives (max 262 m), fish remained surface oriented with short excursions below the isothermal layer but larger OAX fish (fork length [103 cm, 120 cm]) inhabiting warmer waters (sea surface temperatures (SST) > ~ 26 °C) spent more time below the isothermal layer than smaller fish (fork length [90 cm, 112 cm]) inhabiting colder WBC surface waters (SST > ~ 22 °C). Conclusions This study reveals movements of dolphinfish that infer regional differences in thermal habitat utilization and displacement over time. This inference evokes questions important to fisheries management regarding the three-dimensional extent of the dolphinfish’s realized thermal niche, its population structure, and the spatiotemporal connectivity of its habitats within the multinational EPO. With improved tag retention, longer deployments should capture increasing displacements along observed axes (N/S vs. E/W); the orientation of seasonal displacement axes suggest longer-distance movements would provide opportunities for reproductive mixing via trans-national migrations.

The common dolphinfish (Coryphaena hippurus) is an epipelagic thermophilic species with a worldwide distribution in tropical and subtropical regions that is characterized by its migratory behavior and fast growth rates. This species is targeted by artisanal small-scale and recreational fisheries in most regions where it is found. This paper updates and analyzes the global scientific knowledge on the biology and ecology of this species, which was last revised at a regional level 20 years ago. This review showed an increase in knowledge about the population structure and regional differences in biological traits, in parallel with a notable lack of mechanistic and even empirical knowledge about the ecology of this species, which hampers a good understanding of the population dynamics and the potential impacts of environmental change. This paper also updates the information about the Mediterranean dolphinfish fishery, where the main four countries that exploit this species deploy 30% of fish aggregation devices (FAD) worldwide. The results suggest, among other effects, some temporal synchronicity in landings across countries, potential interannual stock movement affecting inter-country catches, diverging trends in prices and insufficient quality in the estimates of fishing effort. The authors propose a suite of specific measures to ameliorate this lack of knowledge and to better manage this complex living resource., Vicenç Moltó acknowledges a predoctoral grant funded by the Regional Government of the Balearic Islands and the European Social Fund. This work was partially funded by two FAO Projects: CopeMed phase II “Coordination to Support Fisheries Management in the Western and Central Mediterranean” and MedSudMed “Assessment and Monitoring of the Fishery Resources and the Ecosystems in the Straits of Sicily”, both co-funded by the Spanish and the Italian Ministries of Agriculture, Fishery and Food, and by the Directorate-General for Maritime Affairs and Fisheries of the European Commission (DG-MARE). The work was partially supported by project CERES (H2020, EU 678193).

This study provides sound evidence of the spawning activity of common dolphinfish (Coryphaena hippurus) in the Gulf of Cadiz (southwest Spain) during summer months. Along with waters off Côte d'Ivoire, this area adjacent to the Mediterranean Sea is the easternmost Atlantic spawning ground documented for the species. All the fish analysed (5 males and 15 females) were at spawning stage, except the smallest female (61.5 cm in fork length), which might not have yet reached sexual maturation. The oceanographic conditions during the samplings were similar to those occurring during the peak spawning season in the Gulf of Mexico. The study results are consistent with recent genetic studies indicating differentiation between Mediterranean and Atlantic dolphinfish populations, with the Strait of Gibraltar representing a boundary between two distinct reproductive units. The present results may contribute to improve the understanding of the dynamics of dolphinfish population and the management of eastern Atlantic and Mediterranean stocks., SI

More than 9 years since the Fukushima Dai-ichi Nuclear Power Plant Accident (FDNPPA), the impact of FDNPPA on marine biota is being revealed. In this work, the evolution of FDNPPA derived 134Cs, 137Cs and 110mAg in dolphin fishes (Coryphaena hippurus) in the Northwest Pacific from Dec. 2011 to Sept. 2018 were studied. Bioconcentration factors (BCF) of radiocesium (29-69 with the average of 48) in dolphin fishes were calculated. The background level of 137Cs in dolphin fishes (

Place: Sao Paulo Publisher: Inst Oceanografico, Univ Sao Paulo WOS:000600345300001; International audience; Catches of pelagic fish associated to anchored Fish Aggregating Devices have been responsible for increases in income, fish consumption, and even cultural identity of artisanal fishing communities in many developing countries worldwide. Nonetheless, in Brazil, aFAD fishing is still poorly developed and studied. In this experiment, FADs were anchored offshore the city of Recife (Northeastern Brazil) to investigate the potential of moored buoys in the aggregation of commercially important pelagic species near the coast, as an alternative fishing site for artisanal fishers. The behavior of acoustically tagged fish was investigated to assess whether they were attracted to the FADs and how long they remained associated to them. The results indicated that, although economically important species were found near the FADs, they did not remain associated for long periods. From the four species tagged, Acanthocybium solandri, Coryphaena hippurus, Thunnus atlanticus, and Caranx crysos, only the two latter were detected at the FADs. Both species presented a preference for a specific FAD, with stronger site fidelity being recorded for C. crysos. This species presented Total Resident Times (TRTs) of more than a month and continuous residence times of more than 14 consecutive days. T atlanticus, on the other hand, remained around the buoys for short time intervals, with a maximum TRT of only two days. Short diurnal excursions far from the FADs and few longer excursions during nighttime were recorded for C. crysos. These results do not support the possible use of moored FADs near the coast of Recife as an alternative fishing site for artisanal fisheries. It is possible that the geomorphological characteristics of the experimental area did not favor the aggregative behavior of large pelagic fish species, such as tunas, around FADs.

Length-weight relationships (LWRs) were estimated for Pacific blue marlin ( Makaira nigricans ), striped marlin ( Kajikia audax ), sailfish ( Istiophorus platypterus ), dolphinfish ( Coryphaena hippurus ) and yellowfin tuna ( Thunnus albacares ). These five fish species are key top predators of the pelagic ecosystem and are economically important resources in the sport fishing of Baja California Sur, Mexico. Overall, 53,359 length and weight records were analyzed for the period 1990-2015. LWRs were significant ( P < 0.05), with b -values ranging from 2.52 to 3.13.

Estimates of discard mortality are difficult to obtain. Meta-analysis or life-history-based approaches to estimate discard mortality could provide informed estimates when direct empirical estimates are not available. We used data from published literature across a variety of fish species to determine if hooking condition (good vs. poor) and species-specific values for the Brody growth coefficient (K: a measure of fish physiology) were meaningful factors influencing discard mortality in hook and line fisheries. We then examined whether a two-step approach, combining condition- and physiology-specific estimates of discard mortality with data on proportion-by-hooking-condition hooking information for a fishery, could result in an estimate of discard mortality for dolphinfish Coryphaena hippurus comparable to an empirical estimate. A model with hooking condition, K and their interaction best fitted the published discard mortality data. K was an important negative covariate of discard mortality for good hooking condition, with higher K species experiencing greater rates of survival. In contrast, species in poor condition had similarly low rates of survival across a range of K values. Results suggests that hooking condition is the dominant source of mortality when fish are hooked in vital areas but that physiology should also be taken into account when estimating discard mortality for good condition fish. For the recreational dolphinfish fishery in the southeastern US, we estimated a median proportional discard mortality rate of 0.12 (95 % credible set: 0.07, 0.17) when combining the meta-analysis and field-collected proportion-by-condition data. This estimate was lower than the empirical estimate of dolphinfish discard mortality but the credible sets overlapped (median: 0.25; 95 % credible set: 0.05, 0.39). Estimates of discard mortality from our meta-analytic approach may be applicable to fisheries where empirical estimates of discard mortality are not available and hooking injuries are the dominant source of mortality.

Successful culture of marine fish relies upon availability of high quality fertilized eggs obtained from broodstock. However, some of the most critical aspects of obtaining such eggs are often overlooked. These aspects include the capture, transport, acclimation, and spawning of sexually mature wild-caught fish. Mahi-mahi ( Coryphaena hippurus ), also known as dolphinfish, have been identified as one of the most promising candidate species for development of warm-water marine finfish aquaculture due to their high growth rate, market presence, and global distribution. In addition, mahi-mahi have proven to be a useful model species for physiology and environmental toxicology research, specifically in studies examining tropical and subtropical pelagic teleosts. One of the keys to aquaculture development of this species is the ability to obtain year-round production of fertilized embryos. This study documents the technical methods utilized to reach a point of consistent mahi-mahi egg production year-round, while also detailing the live transport tank and land-based spawning tank design, implementation, and operation. Following three different groups of wild-caught mahi-mahi broodstock from the point of capture throughout their lifespan, this study provides novel information on growth, survival, and spawning of this species in captivity. Results from this research have allowed for significant new insights into the effects of a variety of environmental stressors on the early life stages of this species. Furthermore, the ability to maintain consistent spawning populations of mahi-mahi in captivity has allowed for reliable and consistent production of fully-weaned fingerlings of this species, thereby resolving one of the key industry bottlenecks that has been limiting expansion of mahi-mahi commercial-scale aquaculture.

Mahi-mahi Coryphaena hippurus is a promising species for aquaculture development and has been used as a model species for oil toxicology and physiology studies. This species has one of the fastest growth rates of any marine teleost and a unique reproductive biology due to its high spawning frequency and reproductive energy allocation. These characteristics lend the species to being an excellent model for understanding broodstock nutrition for other high energetic pelagic species. In this study, egg morphometrics and larval survival were tracked over a 10-week period from the initial capture of wild mahi-mahi broodstock. Larval quality from subsequent spawns collected over time was quantified using larval survival activity indices (SAIs) as a metric to assess egg quality. Larval SAIs were maintained and did not significantly decrease (p

In this communication, an abnormally hermaphroditic specimen of common dolphin fish, Coryphaena hippurus, is reported from Indian waters. Morphological and histological studies clearly revealed the presence of developing ovary and testis with series of gametogenetic cells. This is the first case of hermaphroditism in common dolphin fish.

Coryphaena hippurus, ou dourado, é uma espécie popular de peixe pescada em torneios de pesca esportiva do Iate Clube do Rio de Janeiro, a qual é comercializada na própria peixaria do clube, devido í­Â apreciação de sua carne. Contudo a presença de helmintos, inclusive na musculatura, resulta em perdas comerciais devido ao seu aspecto repugnante. O objetivo desta investigação foi identificar taxonomicamente estes helmintos utilizando dados de análises morfométricas e morfológicas através das microscopias ótica e eletrônica de varredura e determinar sua significí­¢ncia higiênico-sanitária. Em janeiro e novembro de 2014, sete espécimes de C. hippurus foram necropsiados e seus órgãos investigados. Os helmintos encontrados foram identificados como plerocercoides de Tentacularia coryphaenae, um cestoide Trypanorhyncha. Os sete espécimes de C. hippurus estavam parasitados por um total de 204 plerocercoides, tendo como sí­­tios de infecção a musculatura, mesentério, estômago e serosa do fí­­gado. Além da repugní­¢ncia destes parasitos, a presença de plerocercoides é um fator preocupante, porque há o risco de reações alérgicas em humanos, salientando-se, então, a significí­¢ncia higiênico-sanitária no monitoramento destes parasitos.

Seasonal forecasting of environmental conditions and marine species distribution has been used as a decision support tool in commercial and aquaculture fisheries. These tools may also be applicable to species targeted by the recreational fisheries sector, a sector that is increasing its use of marine resources, and making important economic and social contributions to coastal communities around the world. Here, a seasonal forecast of the habitat and density of dolphinfish (Coryphaena hippurus), based on sea surface temperatures, was developed for the east coast of New South Wales (NSW), Australia. Two prototype forecast products were created; geographic spatial forecasts of dolphinfish habitat and a latitudinal summary identifying the location of fish density peaks. The less detailed latitudinal summary was created to limit the resolution of habitat information to prevent potential resource over-exploitation by fishers in the absence of total catch controls. The forecast dolphinfish habitat model was accurate at the start of the annual dolphinfish migration in NSW (December) but other months (January - May) showed poor performance due to spatial and temporal variability in the catch data used in model validation. Habitat forecasts for December were useful up to five months ahead, with performance decreasing as forecast were made further into the future. The continued development and sound application of seasonal forecasts will help fishery industries cope with future uncertainty and promote dynamic and sustainable marine resource management.

Identifying prey resource pools supporting fish biomass can elucidate trophic pathways of pollutant bioaccumulation. We used multiple chemical tracers (carbon [δ(13)C] and nitrogen [δ(15)N] stable isotopes and total mercury [THg]) to identify trophic pathways and measure contaminant loading in upper trophic level fishes residing at a reef and open-ocean interface near Eleuthera in the Exuma Sound, The Bahamas. We focused predominantly on the trophic pathways of mercury bioaccumulation in dolphinfish Coryphaena hippurus and wahoo Acanthocybium solandri, 2 commonly consumed pelagic sportfish in the region. Despite residing within close proximity to productive and extensive coral reefs, both dolphinfish and wahoo relied almost exclusively on open-ocean prey over both short and long temporal durations. A larger isotopic niche of dolphinfish suggested a broader diet and some potential prey differentiation between the 2 species. THg concentrations in dolphinfish (0.2 ± 0.1 ppm) and wahoo (0.3 ± 0.3 ppm) were mostly below recommended guidelines for humans (US Environmental Protection Agency (EPA) = 0.3 ppm, US Food and Drug Administration (FDA)= 1.0 ppm) and were within ranges previously reported for these species. However, high THg concentrations were observed in muscle and liver tissue of commonly consumed reef-associated fishes, identifying a previously unrecognized route of potentially toxic Hg exposure for human consumers on Eleuthera and neighboring islands.

Hidayati D, Oclandhi B, Maulidinia N, Sa’adah NN, Nurhayati APD. 2019. Short Communication: The species and body size composition of pelagic fishes that caught by troll line in the fish landing of Sendang Biru, East Java, Indonesia. Biodiversitas 20: 1764-1769. Troll line is the most used pelagic fishing gear for fishermen in Sendang Biru, the part of Indian ocean at East Java, which have an impact on the catch composition. The study was aimed to obtain data on species composition and size of pelagic fish caught in troll line in Sendang Biru, East Java, Indonesia. Fish samples were collected from nine different vessels landed in Sendang Biru for three days in April 2018. The composition of fish species was measured based on relative abundance. The fish size composition was obtained by measuring fork length which is also used to determine the stage of development of juvenile (Jv) or adult (Ad) fish. The results of the research showed there were four pelagic fish species which dominated by Katsuwonus pelamis or skipjack tuna (50.05%) and Thunnus albacares or yellowfin tuna (47.95%) and a small amount of Coryphaena hippurus and Makaira mazara. According to the body size, the fish caught by troll line in Sendang Biru is dominated by adult skipjack tuna (41-60 cm) and juvenile yellowfin tuna (21-78 cm).

In the Mediterranean Sea, recreational fishing is a popular activity and anglers catch a significant amount of fish which could represent more than 10% of the total harvesting in a littoral area. The Portofino Marine Protected Area, established in 1999 in the Ligurian Sea (North-Western Mediterranean), traditionally hosts a well-developed recreational fishery. Aim of this study has been to characterize the activities of the local anglers, analysing their annual harvesting within and around the Portofino MPA and the species composition of the catches. This was possible studying data from the mandatory anglers’ logbooks, and through interviews and surveys at sea. In 2015, the 340 checked anglers fished, in average, 1 kg/day, on average, mainly by trolling or handlining systems. Each fisherman, during 25 (± 21) trips, fished approximately 25 kg/year, for a total harvesting of about 8-9 t/year. Seriola dumerili, with 230 kg/year, was the species most caught in terms of biomass. It was followed by Coryphaena hippurus (130 kg/year). In addition, the analysis of catches occurring during local fishing competitions organized off the MPA limits suggested a harvesting capacity for each angler varying between 0.7 and 1.1 kg/angler per day, depending on the used gear (handlining, trolling, spear-guns). Finally, 36% of the anglers claimed to hook often the hard bottom seabed, often losing nylon lines. Consequently, the Management Body of the Portofino MPA has been advised to suspend recreational fishing activities in the most busy areas for a period of two years, calling for a complete removal of the lost fishing gears.

An experimental study was carried out to determine the costs of freezing artisanally fished Perico (Coryphaena Hippurus) in Peru. A refrigeration chamber was equipped with electrical and temperature sensors to determine the thermal efficiency and thus calculate the costs of freezing the fish. The results indicate that it is possible to freeze and store fish to avoid speculation due to over production and thus improve the selling prices. In this way, it is possible to store the fish until the prices are attractive again so that fishermen sell their product at fair prices and progressively improve their quality of life.

Key differences in the developmental process of pelagic fish embryos, in comparison to embryos of standard test fish species, present challenges to obtaining sufficient control survival needed to successfully perform traditional toxicity testing bioassays. Many of these challenges relate to the change in buoyancy, from positive to negative, of pelagic fish embryos that occurs just prior to hatch. A novel exposure system, the pelagic embryo-larval exposure chamber (PELEC), has been developed to conduct successful bioassays on the early life stages (ELSs; embryos/larvae) of pelagic fish. Using this unique recirculating upwelling system, it was possible to significantly improve control survival in pelagic fish ELS bioassays compared to commonly used static exposure methods. Results demonstrate that control performance of mahi-mahi (Coryphaena hippurus) embryos in the PELEC system, measured as percent survival after 96-hrs, significantly outperformed agitated static exposure and static exposure systems. Similar significant improvements in 72-hr control survival were obtained with yellowfin tuna (Thunnus albacares). The PELEC system was subsequently used to test the effects of photo-induced toxicity of crude oil to mahi-mahi ELSs over the course of 96-hrs. Results indicate a greater than 9-fold increase in toxicity of Deepwater Horizon (DWH) crude oil during co-exposure to ambient sunlight compared to filtered ambient sunlight, revealing the importance of including natural sunlight in 96-hr DWH crude oil bioassays as well as the PELEC system's potential application in ecotoxicological assessments.

The temporal and geographic attributes of the Deepwater Horizon incident in 2010 likely exposed pelagic game fish species, such as mahi-mahi, to crude oil. Although much of the research assessing the effects of the spill has focused on early life stages of fish, studies examining whole-animal physiological responses of adult marine fish species are lacking. Using swim chamber respirometry, the present study demonstrates that acute exposure to a sublethal concentration of the water accommodated fraction of Deepwater Horizon crude oil results in significant swim performance impacts on young adult mahi-mahi, representing the first report of acute sublethal toxicity on adult pelagic fish in the Gulf of Mexico following the spill. At an exposure concentration of 8.4 ± 0.6 µg L-1 sum of 50 selected polycyclic aromatic hydrocarbons (PAHs; mean of geometric means ± standard error of the mean), significant decreases in the critical and optimal swimming speeds of 14% and 10%, respectively (p

Dolphinfish Coryphaena hippurus support important commercial and recreational fisheries in the Gulf of Mexico. Understanding the feeding ecology of this economically important pelagic fish is key to its sustainable management; however, dietary data from this region are sparse. We conducted a comprehensive diet study to develop new trophic baselines and investigate potential ontogenetic and sex-related shifts in Dolphinfish feeding ecology. The stomach contents of 357 Dolphinfish (27.6–148.5 cm TL) were visually examined from fishery-dependent sources off Port Aransas, Texas. Our analyses revealed a highly piscivorous diet with Actinopterygii comprising 70.44% of the stomach contents by number. The most commonly observed taxa were carangid (12.45%N) and tetraodontiform (12.08%N; families Balistidae, Monacanthidae, and Tetraodontidae) fishes. Malacostracans were also common (24.83%N), mostly in the form of pelagic megalopae. Other prey categories included squid and the critically endangered Kemp’s R...

Fisheries management based on an ecosystem approach is currently promoted and, to this end, knowledge of interactions between the components of pelagic ecosystem is crucial. The aim of this study was to evaluate the trophic interactions between some components of marine pelagic ecosystem off the coast of Oaxaca. The stomach contents of five species of fishes caught during fishing tournaments and commercial fishing at the coast of Oaxaca, from May 2000 to July 2002 were analyzed. We analyzed stomach contents of 645 specimens of large predatory fishes, namely Istiophorus platypterus, Coryphaena hippurus, Thunnus albacares, Euthynnus lineatus, and Carcharhinus falciformis. Mayor forage species were Portunus xantusii and Auxis thazard: all predators consumed them in greater or lesser amounts. All fish species had narrow trophic niche breadths (BA

Distinct spatial variation and fisheries exchange routes for dolphinfish ( Coryphaena hippurus ) were resolved relative to the northeastern Caribbean Sea and U.S. east coast using conventional ( n = 742; mean ± SD cm FL: 70.5 ± 15.2 cm FL) and pop-up satellite archival tags ( n = 7; 117.6 ± 11.7 cm FL) from 2008 to 2014. All dolphinfish released in the northeastern Caribbean Sea moved westward (274.42° ± 21.06°), but slower in the tropical Atlantic than Caribbean Sea, with a maximum straight-line distance recorded between San Juan, Puerto Rico, and Charleston, South Carolina (1917.49 km); an 180-day geolocation track was obtained connecting the South Atlantic Bight to the northern limits of the Mona Passage. Two recaptures occurred within the Mona Passage from San Juan, Puerto Rico, and St. John, United States Virgin Islands, providing the first evidence that dolphinfish may cross the Greater Antilles island chain between the Atlantic Ocean and Caribbean Sea in both directions during their migration. To investigate this further, fish movements were compared to surface drifter tracks ( n = 196) in the region. Entry of drifters into the Caribbean Sea from the Atlantic Ocean occurred through the northern Lesser Antilles, the Anegada Passage, and the Mona Passage; both passages were observed to be an entry and exit. Results suggest domestic and international fisheries exchanges occur annually between the United States and Caribbean island nations (Antigua and Barbuda, Anguilla, St. Kitts, United States Virgin Islands, Puerto Rico, Hispaniola, The Bahamas, Cuba, Bermuda), with return migration directed towards the Yucatan Channel/Loop Current (south of the Greater Antilles) or Straits of Florida/Gulf Stream (north). Understanding dolphinfish movements and regional connectivity among exclusive economic zones of northern Caribbean islands and the United States is critical for accurate assessments of fishing mortality, spawning biomass and stock health, and given the regional connectivity, management must be consistent between jurisdictions.

The diet and the feeding habits of the common dolphinfish (Coryphaena hippurus) in the Pacific coast of Ecuador was assessed by examining 320 stomachs of individuals ranging from 51 to 149 cm in total length. Fish was the predominant prey group in the diet (Alimentary Index, %AI = 95.39) followed by cephalopods (%AI = 4.13) and crustaceans (%AI = 0.48). Among the 17 prey items that make up the dolphinfish diet, the Exocoetidae family was the most important prey (%AI = 57.13),Dosidicus gigasbeing the most abundant invertebrate species (%AI = 7.65). Feeding patterns were evaluated using the graphing method of Amundsen, which suggested that this species shows a varying degree of specialization on different prey taxa. Thus, while some species were unimportant and rare (Hippocampus hippocampus, Lagocephalus lagocephalus, Gobiidae andArgonautasp.), several dolphinfishes showed a high degree of specialization on Scombridae,Pleuroncodes planipes, Portunus xantusiiandOpisthonema libertate. Size-related and temporal shifts in dietary composition were investigated by PERMANOVA analysis, which showed wide variations among size classes and periods of capture. The results of this study indicate that the common dolphinfish is an opportunistic feeder, which is capable of consuming a wide variety of schooling epipelagic organisms.

Heavy metals are contaminants of great environmental concern due to their multiple origins (natural and anthropogenic), the ability to accumulate in organs and tissues, and the deleterious effects they can cause in organisms. Studies on the accumulation of metals in seafood, such as fish, have increased in importance due to the risk for human health when consuming fish contaminated by metals. The present work was aimed at verifying the concentrations of cadmium (Cd), mercury (Hg) and lead (Pb) in the muscular tissue and liver of yellowfin tuna (Thunnus albacares) and common dolphinfish (Coryphaena hippurus) from the Eastern Pacific Ocean landed in Manta city, Ecuador. Samples were analyzed by inductively coupled plasma mass spectroscopy (ICP-MS). Around half of the muscle samples of both species presented levels of Cd and Hg above the limits considered safe for human consumption established by the European Union. For Pb,most of the muscle samples were considered acceptable for consumption. Results indicate that both species should be consumed with some caution. Considering the tolerable weekly intake recommended for adults by the World Health Organization, results indicate that Hg is the main metal that limits the consumption of yellowfin tuna and common dolphinfish, with a recommended maximum ingestion, respectively, of 191 and 178 g per week for an adult.c

We report the occurrence of macroplastic debris in the stomach of a common dolphinfish (Coryphaena hippurus) caught in the Western Equatorial Atlantic. On the deck, we noticed that the fish was remarkably undernourished and decided to remove its stomach for laboratory analysis. A large part of a plastic bowl and a tuna pectoral fin were the only items recorded in the fish stomach. The plastic measured 99.57 cm2 and weighed 12.77 g, likely blocking the digestive tract and reducing food intake by the fish, as supported by signs of starvation. This is the record of the largest plastic debris ingested by a dolphinfish to date. As the source of the plastic container was probably a tuna fishing boat, we suggest strengthening environmental education programs to enhance the awareness of fishermen and mitigate the impacts of plastic pollution on the pelagic ecosystem and associated organisms, such as C. hippurus.

The common dolphinfish (Coryphaena hippurus) is an important resource for the sport-fishing industry in Mexico. It is captured incidentally by the eastern Pacific purse-seine tuna fishery and in coastal areas by artisanal fisheries. Although it is considered a highly migratory species, only few studies of its movements are available. In this study, the behavior of the common dolphinfish was analyzed by means of acoustic telemetry at three locations within La Paz Bay (southern Gulf of California) from summer to autumn 2013. Acoustic transmitters were attached to six individuals and they were tracked for periods of up to 48 h. Every hour, vertical profiles of temperature and bathymetry were made. To determine the effect of biotic (sex) and abiotic (water temperature and depth, thermocline depth, hour, and bathymetry) variables on the horizontal and vertical movements of tagged organisms, generalized additive mixed models were applied. The results showed a tendency of horizontal movements to the southwestern zone of the bay; two individuals crossed from the eastern to the western side. The average speed was 0.51 m s–1. The vertical movements showed that the individuals spent 80% of the time above 34 m depth, of which around 45% was spent in the upper 10 m of the water column. During daylight hours they swam in shallow waters (upper 10 m) and at night they performed deeper dives (73 m maximum depth). Biotic and abiotic variables influenced both types of movements; however, bathymetry and temperature largely explained fish movements.

Defining the oceanic habitats of migratory marine species is important for both single species and ecosystem-based fisheries management, particularly when the distribution of these habitats vary temporally. This can be achieved using species distribution models that include physical environmental predictors. In the present study, species distribution models that describe the seasonal habitats of two pelagic fish (dolphinfish, Coryphaena hippurus and yellowtail kingfish, Seriola lalandi), are developed using 19 yr of presence-only data from a recreational angler-based catch-and-release fishing programme. A Poisson point process model within a generalized additive modelling framework was used to determine the species distributions off the east coast of Australia as a function of several oceanographic covariates. This modelling framework uses presence-only data to determine the intensity of fish (fish km(-2)), rather than a probability of fish presence. Sea surface temperature (SST), sea level anomaly, SST frontal index and eddy kinetic energy were significant environmental predictors for both dolphinfish and kingfish distributions. Models for both species indicate a greater fish intensity off the east Australian coast during summer and autumn in response to the regional oceanography, namely shelf incursions by the East Australian Current. This study provides a framework for using presence-only recreational fisheries data to create species distribution models that can contribute to the future dynamic spatial management of pelagic fisheries.

Shearwaters are ideal for monitoring ocean conditions in the California Current because these predators are abundant, conspicuous, and responsive to oceanographic variability. Herein we evaluated black-vented ( Puffinus opisthomelas ), Buller's ( P. bulleri ), flesh-footed ( P. carneipes ), pink-footed ( P. creatopus ), short-tailed ( P. tenuirostris ), and sooty ( P. griseus ) shearwaters as fishery-independent indicators of predatory or prey fish availability. We analyzed four years (1996, 2001, 2005, 2008) of monthly (August–November) National Oceanic and Atmospheric Administration seabird surveys, and United States Geological Survey Pacific Coast Fisheries Database catch, from the California coast to 200 nm offshore. An ordination of shearwater abundance and fish catch revealed that the shearwaters and 11 fish/squid species were significantly correlated with one or more of three principal components, which explained 86% of the variation and revealed distinct species assemblages. We evaluated multiple linear regression models for 19 fisheries using five shearwater metrics: density, aggregation, and behavior (traveling, stationary, feeding), three oceanographic indices, and latitude. Eight of these models had a shearwater metric as the primary predictor. In particular, feeding black-vented shearwater abundance explained 75% of dolphinfish ( Coryphaena hippurus ) longline catch. This research illustrates the utility of shearwaters as ecosystem indicators, with direct application for predicting fishery catch of commercial importance.

The sampling of fish from the artisanal fleet operating with surface lines off north-eastern Brazil was carried out between 1998 and 2000. Generalized linear models (GLMs) were used to standardize mean abundance indices using catch and fishing effort data on dolphinfish Coryphaena hippurus and to identify abundance trends in time and space, using 1215 surface line deployments. A standard relative abundance index (catch per unit effort, CPUE) was estimated for the most frequent vessels used in the sets, employing factors and coefficients generated in the GLMs. According to the models, C. hippurus catches are affected by the operating characteristics and power of different fishing vessels. These differences highlight the need for standardization of catch and effort data for artisanal fisheries. The highest mean abundance values for C. hippurus were off the state of Rio Grande do Norte, with an increasing tendency in areas with greater depths and more distant from the coast, reaching maximal values in areas whose depths range from 200 to 500 m. The highest mean abundance values occurred between April and June. The higher estimated abundance of C. hippurus in this period off the state of Rio Grande do Norte and within the 200-500 m depth range may be related to a migration pattern of food sources, as its main prey, the flying fish Hirundichthys affinis, uses floating algae as refuge and to deposit its pelagic eggs.

OBJECTIVE: To study the food habits of a sample of the dolphinfish (Coryphaena hippurus) around the Petrobrás PXIV oil platform located off Southern Brazil. Methods: We examined the stomach contents of 28 adult dolphinfish caught around this platform between 2000 and 2001. RESULTS: Results highlighted a diet consisting mainly of pelagic fish, although cephalopods and crustaceans are also present. A large amount of clupeids found in the stomachs could be due to baits used by fishermen that do fish around the platform. CONCLUSIONS: In this research we discuss the possibility of this occurrence being related to trophic opportunistic behavior. This could be a reason why adult dolphinfish are attracted by this platform since the whole structure does act as a fish aggregating device. info:eu-repo/semantics/publishedVersion

Dolphinfish (Mahimahi) are a high-demand resource for sport and coastal fisheries, mainly in the Pacific Ocean. Due to their economic and ecological importance, studies of their biology are very important to understand their function in ecosystems. We used stable isotope and stomach content analyses to determine the most important prey of the common dolphinfish, as well as the trophic level of this species in two areas of the southern Gulf of California. Stomach contents of 445 specimens were analysed. Using both techniques, we found that the most important prey for dolphinfish in the southern Gulf of California were three invertebrate species followed by fish. This contrasts with results from other authors who found that this species was mainly piscivorous in other locations. Stomach content analysis indicated differences in prey biomass by area, season and size class. The isotopic analysis did not show significant differences between seasons or sexes. Both stomach contents and stable isotope analyses showed that although this predator consumed a wide prey spectrum, only a few prey items made up the bulk of the diet, which resulted in a low SD in δ15N values and low Levin's index values. We conclude that this fish is an opportunistic predator that may consume a wide prey spectrum, but that it mainly consumes prey that are abundant in the area, such as crustaceans and cephalopods in the Gulf of California.

Negative impacts of CO2-induced ocean acidification on marine organisms have proven to be variable both among and within taxa. For fishes, inconsistency confounds our ability to draw conclusions that apply across taxonomic groups and highlights the limitations of a nascent field with a narrow scope of study species. Here, we present data from a series of 3 experiments on the larvae of mahi-mahi Coryphaena hippurus, a large pelagic tropical fish species of high eco- nomic value. Mahi-mahi larvae were raised for up to 21 d under either ambient seawater condi- tions (350 to 490 µatm pCO2) or projected scenarios of ocean acidification (770 to 2170 µatm pCO2). Evaluation of hatch rate, larval size, development, swimming activity, swimming ability (Ucrit), and otolith (ear stone) formation produced few significant effects. However, larvae unex- pectedly exhibited significantly larger size-at-age and faster developmental rate during 1 out of 3 experiments, possibly driven by metabolic compensation to elevated pCO2 via a corresponding decrease in routine swimming velocity. Furthermore, larvae had significantly larger otoliths at 2170 µatm pCO2, and a similar but non-significant trend also occurred at 1200 µatm pCO2, sug- gesting potential implications for hearing sensitivity. The lack of effect on most variables meas- ured in this study provides an optimistic indication that this large tropical species, which inhabits the offshore pelagic environment, may not be overly susceptible to ocean acidification. However, the presence of some treatment effects on growth, swimming activity, and otolith formation sug- gests the presence of subtle, but possibly widespread, effects of acidification on larval mahi-mahi, the cumulative consequences of which are still unknown.

Trophic pathways and size-based bioaccumulation rates of total mercury were evaluated among recreationally caught albacore tuna (Thunnus alalunga), yellowfin tuna (Thunnus albacares), shortfin mako shark (Isurus oxyrinchus), thresher shark (Alopias vulpinus), and dolphinfish (Coryphaena hippurus) from offshore southern New England waters of the northwest Atlantic Ocean between 2008 and 2011. Mercury concentrations were highest in mako (2.65 ± 1.16 ppm) and thresher sharks (0.87 ± 0.71 ppm), and significantly lower in teleosts (albacore, 0.45 ± 0.14 ppm; yellowfin, 0.32 ± 0.09 ppm; dolphinfish, 0.20 ± 0.17 ppm). The relationship between body size and mercury concentration was positive and linear for tunas, and positive and exponential for sharks and dolphinfish. Mercury increased exponentially with δ 15N values, a proxy for trophic position, across all species. Results demonstrate mercury levels are positively related to size, diet and trophic position in sharks, tunas, and dolphinfish, and the majority of fishes exhibited concentrations greater than the US EPA recommended limit.