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1
STERGIOU, K., D. C. BOBORI, F. G. EKMEKÇİ, M. GÖKOĞLU, P. K. KARACHLE, G. MINOS, Y. ÖZVAROL, I. SALVARINA, A. S. TARKAN und L. VILIZZI. „New Fisheries-related data from the Mediterranean Sea (April 2014)“. Mediterranean Marine Science 15, Nr. 1 (12.04.2014): 213. http://dx.doi.org/10.12681/mms.738.
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As part of its policy, Mediterranean Marine Science started from 2014 to publish a new series of collective article with fisheries-related data from the Mediterranean Sea. In this first collective article we present length frequencies and weight-length relationships for the northern brown shrimp Farfantepenaeus aztecus in the eastern Mediterranean, length-weight relationships for 10 fish species in the North Aegean Sea, the feeding habits for 11 sparid fishes in the North Aegean Sea, a review of the existing literature on the feeding and reproduction of common carp Cyprinus carpio in Anatolia (Turkey) and mouth dimensions and the relationships between mouth area and length for seven freshwater fishes from Lake Volvi (Northern Greece).
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Nielsen, Einar E., Peter Grønkjær, Dorte Meldrup und Helge Paulsen. „Retention of juveniles within a hybrid zone between North Sea and Baltic Sea Atlantic cod (Gadus morhua)“. Canadian Journal of Fisheries and Aquatic Sciences 62, Nr. 10 (01.10.2005): 2219–25. http://dx.doi.org/10.1139/f05-139.
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Elucidating the relative roles of dispersal and retention of juvenile stages is an important issue for understanding population structure and evolution in marine organisms. We investigated the genetic population structure of juvenile Atlantic cod (Gadus morhua) within the transition zone between the North Sea and the Baltic Sea, employing nine microsatellite loci, and compared our data with adult cod data from the same area. Small but statistically significant overall differentiation (Fst = 0.003) was found among juvenile samples. Samples of juveniles grouped genetically with adult samples from the same geographical regions. Individual admixture analysis of a large sample of juveniles taken within the transition zone showed that the patterns of genetic differentiation could not be explained by mixing of pure North Sea and Baltic Sea individuals. Instead, the high number of juveniles with intermediate genotypes was compatible with a scenario of exclusive local (transition zone) origin. The results support the hypothesis that population structure in marine fishes is maintained by the retention of juveniles.
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Chacón-Monge, José-Leonardo, Arturo Angulo und Jorge Cortés. „New hosts and morphological data for the Star pearlfish Carapus mourlani (Ophidiiformes: Carapidae) from collections made in the North Pacific coast of Costa Rica“. Revista de Biología Tropical 69, Suppl.2 (06.09.2021): S219—S233. http://dx.doi.org/10.15517/rbt.v69isuppl.2.48319.
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Introduction: The family Carapidae includes about 40 species of marine fishes distributed in coastal habitats worldwide. The family includes some free-living species, however, most of them are found as commensal inquilines or parasites of marine invertebrates, including several echinoderm species. In the Eastern Tropical Pacific, the biology and host use of the representatives of the Carapidae is relatively poorly known.
Objective: The present study reports the occurrence of the Star pearlfish Carapus mourlani within three previously unknown hosts in the region: the sea stars Nidorellia armata, Phataria unifascialis, and the sea cucumber Stichopus horrens. Some ecological implications and considerations regarding such symbiotic relationships are raised and discussed. Additional morphometric and meristic data for the fish and the echinoderms are also provided and discussed.
Methods: Echinoderms were collected, from 25 localities along the North Pacific coast of Costa Rica, and were carefully examined searching for commensal/parasitic fishes. Echinoderms and fishes were identified and characterized in accordance with the specialized literature.
Results: A total of 497 echinoderms, including about 60 species, were collected and examined. Commensal/parasitic fish (a single species represented by 13 specimens) were found in three echinoderm specimens/species.
Conclusions: The list of echinoderm hosts for this carapid fish, through its whole distribution range, rises to 12 species (six sea stars and six sea cucumbers) and that could be a consequence of its wide geographic distribution, its generalist feeding habits and opportunistic commensal behavior.
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Lefort, Kyle J., Heather L. Major, Alexander L. Bond, Antony W. Diamond, Ian L. Jones, William A. Montevecchi, Jennifer F. Provencher und Gregory J. Robertson. „Long-term stability in the volume of Atlantic Puffin (Fratercula arctica) eggs in the western North Atlantic“. Canadian Journal of Zoology 99, Nr. 8 (August 2021): 653–57. http://dx.doi.org/10.1139/cjz-2020-0254.
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In the eastern North Atlantic, declines in the volume of Atlantic Puffin (Fratercula arctica (Linnaeus, 1758)) eggs have been associated with shifts in the marine ecosystem, such as changes in the abundance of forage fishes and increasing sea-surface temperatures. In the western North Atlantic, where similar shifts in oceanographic conditions and changes in the abundance of forage fishes have presumably occurred, trends in the volume of Atlantic Puffin eggs remain unknown. In this study, we investigate Atlantic Puffin egg volume in the western North Atlantic. We compiled 140 years (1877–2016) of egg volume measurements (n = 1805) and used general additive mixed-effects models to investigate temporal trends and regional variation. Our findings indicate that Atlantic Puffin egg volume differs regionally but has remained unchanged temporally in the western North Atlantic since at least the 1980s.
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Gordó-Vilaseca, Cesc, Laurene Pecuchet, Marta Coll, Henning Reiss, Alexander Jüterbock und Mark John Costello. „Over 20% of marine fishes shifting in the North and Barents Seas, but not in the Norwegian Sea“. PeerJ 11 (31.08.2023): e15801. http://dx.doi.org/10.7717/peerj.15801.
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Climate warming generally induces poleward range expansions and equatorward range contractions of species’ environmental niches on a global scale. Here, we examined the direction and magnitude of species biomass centroid geographic shifts in relation to temperature and depth for 83 fish species in 9,522 standardised research trawls from the North Sea (1998–2020) to the Norwegian (2000–2020) and Barents Sea (2004–2020). We detected an overall significant northward shift of the marine fish community biomass in the North Sea, and individual species northward shifts in the Barents and North Seas, in 20% and 25% of the species’ biomass centroids in each respective region. We did not detect overall community shifts in the Norwegian Sea, where two species (8%) shifted in each direction (northwards and southwards). Among 9 biological traits, species biogeographic assignation, preferred temperature, age at maturity and maximum depth were significant explanatory variables for species latitudinal shifts in some of the study areas, and Arctic species shifted significantly faster than boreal species in the Barents Sea. Overall, our results suggest a strong influence of other factors, such as biological interactions, in determining several species’ recent geographic shifts.
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Agiadi, Konstantina, Efterpi Koskeridou und Danae Thivaiou. „At the crossroads: early Miocene marine fishes of the proto-Mediterranean Sea“. Fossil Record 24, Nr. 2 (26.07.2021): 233–46. http://dx.doi.org/10.5194/fr-24-233-2021.
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Abstract. Connectivity and climate control fish distribution today as well as in the geological past. We present here the Aquitanian (early Miocene) marine fish of the Mesohellenic Basin, a restricted basin at the border between the proto-Mediterranean and Paratethyan seas. Based on fish otoliths, we were able to identify 19 species from 17 genera, including two new species: Ariosoma mesohellenica and Gnathophis elongatus. This fish assemblage, in conjunction with the accompanying molluscan assemblage, indicates a variable shelf paleoenvironment with easy access to the open ocean. Although available data on the Indo-Pacific fishes of the early Miocene are very limited, the fish fauna of the Mesohellenic Basin has many elements in common with the North Sea, the NE Atlantic, and the Paratethys.
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Bănaru, Daniela, und Mireille Harmelin-Vivien. „Trophic links and riverine effects on food webs of pelagic fish of the north-western Black Sea“. Marine and Freshwater Research 60, Nr. 6 (2009): 529. http://dx.doi.org/10.1071/mf08005.
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Improving the knowledge of trophodynamics in coastal marine ecosystems is important for fisheries management. The present study was designed to assess the influence of Danube River inputs on Romanian coastal marine food webs of the European sprat (Sprattus sprattus), the European anchovy (Engraulis encrasicholus) and the horse mackerel (Trachurus mediterraneus). Gut content analyses coupled with carbon and nitrogen stable isotope analyses described food web variations with fish size, season and distance from the Danube delta. Sprats fed on zooplankton, horse mackerel fed on polychaetes and small fish, and anchovies had an intermediate diet. The δ13C and δ15N ratios and mean trophic levels increased from sprats to anchovies and then to horse mackerel. Season strongly influenced the δ15N values of the three fishes, with lower values in spring than in autumn linked to higher Danube inputs into coastal waters in spring during the flooding period. Fish condition was related to diet and environmental factors, with higher conditions recorded in the north area in autumn and in the south area in spring. Danube River inputs influenced the diet, stable isotope ratios and condition of the main commercial pelagic migratory fishes of the north-western Black Sea.
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Neat, Francis, und David Righton. „Warm water occupancy by North Sea cod“. Proceedings of the Royal Society B: Biological Sciences 274, Nr. 1611 (19.12.2006): 789–98. http://dx.doi.org/10.1098/rspb.2006.0212.
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The North Sea has warmed in recent years and there is an ongoing debate into how this is affecting the distribution of fishes and other marine organisms. Of particular interest is the commercially important Atlantic cod ( Gadus morhua L.), which has declined sharply in abundance in the North Sea over the past 20 years. Observations of the temperature experienced by 129 individual cod throughout the North Sea were made during a large-scale electronic tagging programme conducted between 1999 and 2005. We asked whether individual cod fully occupied the thermal habitat available to them. To this end, we compared the temperature experience of cod with independently measured contemporaneous sea-bottom temperature data. The majority of cod experienced a warmer fraction of the sea than was potentially available to them. By summer, most of the individuals in the south experienced temperatures considered superoptimal for growth. Cooler waters were within the reach of the cod and a small number of individuals migrated to areas that allowed them to experience lower temperatures, indicating that the cod had the capacity to find cooler water. Most did not, however, suggesting that the changing thermal regime of the North Sea is not yet causing adult cod to move to cooler waters.
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Liu, Shang-Yin Vanson, Chia-Hui Wang, Jen-Chieh Shiao und Chang-Feng Dai. „Population connectivity of neon damsel, Pomacentrus coelestis, inferred from otolith microchemistry and mtDNA“. Marine and Freshwater Research 61, Nr. 12 (2010): 1416. http://dx.doi.org/10.1071/mf10079.
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Understanding dispersal patterns and population connectivity is crucial to the conservation and management of fish assemblages in reef ecosystems. To reveal the population connectivity of reef fishes in the northern West Pacific, we examined the otolith chemistry and the mtDNA control region of Pomacentrus coelestis collected from six localities between Hainan Island (China) and Okinawa (Japan). The results of otolith chemistry analyses on pre-settlement signatures showed that fishes in north-west Taiwan may have a similar origin, whereas those in southern Taiwan might have a separate origin from the South China Sea. Furthermore, the elemental ratios of post-settlement signatures showed clear separation among localities, reflecting their sedentary behaviour after settlement and the influence of local environment. Population genetic analyses revealed that significant genetic differentiation occurred between populations in north-west Taiwan and populations in the South China Sea and the Kuroshio ecosystems. This study demonstrated that otolith chemistry and mtDNA analyses revealed consistent and complementary results of the dispersal and connectivity of P. coelestis populations, and provided evidence supporting that fish populations around Taiwan should be considered as two stocks. Thus, two marine protected area networks should be established for the conservation and management of reef fishes in this area.
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GEROVASILEIOU, V., C. CHINTIROGLOU, D. VAFIDIS, D. KOUTSOUBAS, M. SINI, T. DAILIANIS, Y. ISSARIS, E. AKRITOPOULOU, D. DIMARCHOPOULOU und E. VOUTSIADOU. „Census of biodiversity in marine caves of the eastern Mediterranean Sea“. Mediterranean Marine Science 16, Nr. 1 (05.03.2015): 245. http://dx.doi.org/10.12681/mms.1069.
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Scientific information on the biodiversity of marine caves in the eastern Mediterranean is limited, especially when considering the extensively studied caves of the north-western and central Mediterranean. Aiming to enhance current knowledge regarding cave communities, this study represents a first assessment of the marine cave biota of the eastern Mediterranean, as this has been defined by the European Union’s Marine Strategy Framework Directive (MSFD). Information retrieved from an extensive overview of relevant scientific documents was combined with original data recorded from 23 marine caves of the north-eastern Mediterranean. Our results report a total of 520 taxa recorded in eastern Mediterranean marine caves to date, the majority of which are sponges, polychaetes, rhodophytes, bivalves, fishes, and gastropods. These include several protected, endemic, and alien species. However, not all taxonomic groups have been equally studied among different areas and future studies are expected to raise the number of endemic and alien species. The overall observed trend is that the reported species number is generally related to sampling effort and scientific expertise. The most well-studied marine cave communities of the eastern Mediterranean are those of the Aegean Sea (especially its northern sector), which presented the highest number of species, followed by those of the Levantine. Furthermore, our research in Aegean caves revealed numerous new records for the marine cave fauna of the eastern basin, while several species are reported for the first time in the marine cave habitat. The critical need for further scientific research, monitoring, and conservation of this unique ecosystem was highlighted by (i) the presence of certain species endemic to the eastern Mediterranean coupled with a high proportion of alien species, especially in the Levantine, and (ii) the marine cave habitat availability in isolated insular areas of the eastern Mediterranean.
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Chittenden, Cedar M., Per Fauchald und Audun H. Rikardsen. „Important open-ocean areas for northern Atlantic salmon (Salmo salar) — as estimated using a simple ambient-temperature approach“. Canadian Journal of Fisheries and Aquatic Sciences 70, Nr. 1 (Januar 2013): 101–4. http://dx.doi.org/10.1139/cjfas-2012-0215.
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Tracking salmon migratory behaviour in the open ocean has been a challenge to researchers. As the marine phase essentially determines the size and survival of individuals and populations, it is arguably the most influential life cycle period for salmon population dynamics. Thus, methods providing an understanding of the spatial and temporal patterns of salmon marine migratory behaviour could improve the species' management and conservation. A model was developed that correlated temperature data from archival tags with sea-surface temperatures (SSTs) to identify the probable marine feeding areas of a northeastern Atlantic salmon (Salmo salar) population over 3 years. The marine distribution of the tagged population extended from the Greenland Sea, north to Svalbard, and into the eastern Barents Sea. Higher probability occupancy zones overlapped with the polar front area from September to April during all 3 years. While the migratory behaviour appeared similar between years and seasons, the fish were distributed farther south and west during the autumn of 2007 than during the autumns of 2006 and 2008. This may have been related to warmer summer SSTs and an earlier annual maximum SST. The ambient-temperature approach developed here is a cost-effective way to monitor the open-ocean migratory patterns of surface-oriented marine fishes.
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He, Qingsong, Shuyang Ma, Qinwang Xing, Wenchao Zhang, Haiqing Yu und Zhenjiang Ye. „Nonstationary Responses of Demersal Fishes to Environmental Variations in Temperate Waters of the Northwestern North Pacific under a Changing Climate“. Fishes 6, Nr. 3 (22.07.2021): 22. http://dx.doi.org/10.3390/fishes6030022.
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Although nonstationarity in marine ecosystems has attracted great attention, the nonstationary responses of demersal fishes to environmental variations induced by the changing climate are still not well understood. Here, we collected 21 time series of demersal fishes from 1956 to 2015 to investigate the climate-induced nonstationary responses in temperate waters of the northwestern North Pacific (NWP). We showed that these demersal fishes experienced state shifts in approximately 1986/87, accompanied by abrupt warming over this region. Moreover, the relationships between demersal fishes and sea surface temperature (SST) were found to change between the two identified eras (i.e., a weak relationship before 1986 and a strong negative relationship after 1986), which may be primarily caused by the alternating dominance of the East Asian winter monsoon and mega-ENSO on SST in temperate waters of the NWP. The identified climate-induced nonstationary responses of demersal fishes to SST variability in this study may provide implications for understanding climate-induced biological dynamics, predicting demersal fish fluctuations, coping with potential ecological risks, and the sustainable exploitation of fishery resources in the future climate. Note that the impact of fishing on the demersal fishes in temperate waters of the NWP was not assessed in this study due to the lack of fishing effort data and therefore the conclusions of our research should be approached with caution.
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Dulvy, Nicholas K., Simon Jennings, Stuart I. Rogers und David L. Maxwell. „Threat and decline in fishes: an indicator of marine biodiversity“. Canadian Journal of Fisheries and Aquatic Sciences 63, Nr. 6 (01.06.2006): 1267–75. http://dx.doi.org/10.1139/f06-035.
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Recent policy commitments aim to reduce biodiversity loss and integrate environmental concerns into fisheries management. However, there are few operational indicators for reporting biodiversity trends and judging progress in relation to management objectives. Here we develop a threat indicator based on the population status of a suite of 23 North Sea fishes from 1982 to 2001 estimated using World Conservation Union (IUCN) Red List decline criteria. The composite indicator was calculated from the weighted average of the threat scores of individual species in each year and varies from 0 to 3, where a score of 3 is equivalent to each species qualifying as "critically endangered". The proportion of threatened fishes, their degree of threat, and the composite indicator value increased steadily over time. The composite indicator value has been >1 since the late 1990s, equivalent to all species meeting the "vulnerable" criterion. A suitable reference trajectory, consistent with the World Summit on Sustainable Development commitment to "achieve by 2010 a significant reduction of the current rate of biodiversity loss" would be a significant reduction in the rate of increase in this indicator before 2010, a limit reference point could be 1 (all species vulnerable) and a target reference point could be 0 (no threatened species).
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Chernova, N. V. „Overview of the fish fauna of the Chaunskaya basin – the area of the natural reserve "Chaunskaya Guba" and the port of Pevek (East Siberian Arctic)“. Proceedings of the Zoological Institute RAS 326, Nr. 1 (25.03.2022): 30–42. http://dx.doi.org/10.31610/trudyzin/2022.326.1.30.
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The fishes of the Chaunskaya Bay and its Basin have been little studied. Part of the coast of this vast Arctic estuary (about 9 thousand km2) is included in the state nature reserve “Chaunskaya Guba”; at the entrance to the bay there is the seaport of Pevek, a transit hub of the Northern Sea Route. The area has been identified as one of the priorities for the protection of biodiversity in the seas of the Russian Arctic. Solving the problem of biota conservation begins with an inventory of the fauna. The paper presents the results of summarizing data on the species composition of marine, anadromous and freshwater fishes in the Chaunskaya Bay and its basin. The updated list includes 36 species of 28 genera, 16 families and 10 orders. In marine waters there are 31 species (18 marine, 13 anadromous and semi-anadromous fish), in rivers and lakes there are 5 freshwater (and 13 anadromous and semi-anadromous) species. The Muksun Coregonus muksun (Pallas, 1814) and the pike Esox lucius Linnaeus, 1758, which were absent in the fauna lists, are added. The lamprey Lethenteron kessleri (Anikin, 1905), the Pacific herring Clupea pallasii Valenciennes, 1847, and the Arctic charr Salvelinus alpinus (Linnaeus, 1758), which were previously recorded, are not confirmed by reliable findings. The marine fish community of the Chaunskaya Bay is an impoverished shelf fauna of the East Siberian Sea and includes species adapted to desalination. The freshwater ichthyofauna of the basin differs from the fauna of the neighboring Kolyma River region in the loss of a number of freshwater species, which are believed to have been extinct because of the Holocene cooling. A significant part of the fish complex consists of elements of the North Pacific fauna that spread to the East Siberian Sea in the postglacial period.
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Thayer, Julie A., Douglas F. Bertram, Scott A. Hatch, Mark J. Hipfner, Leslie Slater, William J. Sydeman und Yutaka Watanuki. „Forage fish of the Pacific Rim as revealed by diet of a piscivorous seabird: synchrony and relationships with sea surface temperature“. Canadian Journal of Fisheries and Aquatic Sciences 65, Nr. 8 (August 2008): 1610–22. http://dx.doi.org/10.1139/f08-076.
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We tested the hypothesis of synchronous interannual changes in forage fish dynamics around the North Pacific Rim. To do this, we sampled forage fish communities using a seabird predator, the rhinoceros auklet ( Cerorhinca monocerata ), at six coastal study sites from Japan to California. We investigated whether take of forage fishes was related to local marine conditions as indexed by sea surface temperature (SST). SST was concordant across sites in the eastern Pacific, but inversely correlated between east and west. Forage fish communities consisted of anchovy ( Engraulis spp.), sandlance ( Ammodytes spp.), capelin ( Mallotus spp.), and juvenile rockfish ( Sebastes spp.), among others, and take of forage fish varied in response to interannual and possibly lower-frequency oceanographic variability. Take of primary forage species were significantly related to changes in SST only at the eastern sites. We found synchrony in interannual variation of primary forage fishes across several regions in the eastern Pacific, but no significant east–west correlations. Specifically in the Japan Sea, factors other than local SST or interannual variability may more strongly influence forage fishes. Predator diet sampling offers a fishery-independent, large-scale perspective on forage fish dynamics that may be difficult to obtain using conventional means of study.
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Pauly, Daniel, und Çetin Keskin. „Temperature constraints shaped the migration routes of mackerel (Scomber scombrus) in the Black Sea“. Acta Adriatica 58, Nr. 2 (22.12.2017): 337–44. http://dx.doi.org/10.32582/aa.58.2.12.
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Conventional narratives explain fish migrations in term of requirements (food, mates, habitats, etc.), with adequate temperatures being optional. Here, using the example of a (commercially extinct) stock of Black Sea mackerel (Scomber scombrus), we suggest that seasonal migrations are driven by seasonal temperature cycles. Therein, temperature acts as a constraint determining where the fish can be at any given time, and not a one of several factors which they would consider when choosing between alternative migration routes. Generalizing, we suggest that temperature should generally be an explicit part of hypotheses about the migratory behaviours of marine fishes. For illustration of what may occur when this is not the case, it is suggested that the non-consideration of temperature in a model of North Atlantic mackerel migration may have led, among the researchers concerned, to a sense of complacency with respect to the climate change-induced changes in the phenology of this fish in the North Atlantic, whose distribution and migration are misleadingly seen as “stochastic”.
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BÁEZ, JOSÉ CARLOS, CRISTINA RODRÍGUEZ-CABELLO, RAFAEL BAÑÓN, ALBERTO BRITO, JESÚS M. FALCÓN, TOÑO MAÑO, JORGE BARO et al. „Updating the national checklist of marine fishes in Spanish waters: An approach to priority hotspots and lessons for conservation“. Mediterranean Marine Science 20, Nr. 2 (12.04.2019): 260. http://dx.doi.org/10.12681/mms.18626.
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In response to a request from the Spanish Ministry of Farming, Fishing, Food, and Environment (Spanish: Agricultura, Pesca, Alimentación y Medio Ambiente) in 2015, a fish expert group was formed to provide a reference list of marine fish species according to five regions (marine demarcations) established by Spanish Law 41/2010 on the protection of the marine environment. The objective of this article was to update and analyse the data compiled in the marine fish species checklist in order to: 1) provide a complete list of marine fish species in the Spanish Exclusive Economic Zone; 2) compare this checklist between bio-geographical areas; and 3) identify possible priority hotspots for their conservation. We applied several indices, such as the total number of species in each area, species richness, and the Biodiversity Conservation Concern index. We discuss gaps in knowledge and the lessons learned for conservation purposes. A total of 1075 marine fishes were reported in Spanish waters. Most of these fish were well determined, whereas a few were treated as uncertain. The marine demarcation with the most species is the Canary Islands with 795 species, followed by the Spanish north coast demarcation with 506 species. However, the marine demarcations with the most species per area are the Spanish coast of the Gulf of Cádiz and the Strait of Gibraltar-Alboran Sea.
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Papenmeier, Svenja, Alexander Darr, Peter Feldens und Rune Michaelis. „Hydroacoustic Mapping of Geogenic Hard Substrates: Challenges and Review of German Approaches“. Geosciences 10, Nr. 3 (09.03.2020): 100. http://dx.doi.org/10.3390/geosciences10030100.
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Subtidal hard substrate habitats are unique habitats in the marine environment. They provide crucial ecosystem services that are socially relevant, such as water clearance or as nursery space for fishes. With increasing marine usage and changing environmental conditions, pressure on reefs is increasing. All relevant directives and conventions around Europe include sublittoral hard substrate habitats in any manner. However, detailed specifications and specific advices about acquisition or delineation of these habitats are internationally rare although the demand for single object detection for e.g., ensuring safe navigation or to understand ecosystem functioning is increasing. To figure out the needs for area wide hard substrate mapping supported by automatic detection routines this paper reviews existing delineation rules and definitions relevant for hard substrate mapping. We focus on progress reached in German approval process resulting in first hydroacoustic mapping advices. In detail, we summarize present knowledge of hard substrate occurrence in the German North Sea and Baltic Sea, describes the development of hard substrate investigations and state of the art mapping techniques as well as automated analysis routines.
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Pangkey, Henneke, Joice R. S. T. L. Rimper und Kurniati Kemer. „Alkaline proteinase in muscle of commercial fishes“. AQUATIC SCIENCE & MANAGEMENT 1, Nr. 1 (30.04.2013): 89. http://dx.doi.org/10.35800/jasm.1.1.2013.1974.
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Sea products are valuable resources of natural substances such as lipids, polysaccharides, enzymes, vitamins, and proteins. Fish proteases have been characterized and some purified. Many of these enzymes display potentially interesting new biochemical properties for biotechnological applications. In this research, we have found activity of some proteases (alkaline proteinase, cathepsin S and cathepsin D) in muscle tissues of marine tropical commercial fish species in North Sulawesi (i.e. Epinephelus fuscoguttatus, Caranx ferdau, Lutjanus malabricus, and Katsuwonus pelamis). All of these fish are economical species with low prices that are highly consumed by local people©Produk yang berasal dari laut merupakan sumberdaya yang kaya akan bahan-bahan alamiah seperti lipida, polisakarida, enzim, vitamin dan protein. Beberapa enzim protease pada ikan telah diidentifikasi dan dimurnikan. Banyak dari enzim ini menunjukkan potensi yang penting sebagai bahan biokimia yang baru. Pada penelitian ini, kami menemukan beberapa jenis protease (alkalin proteinase, katepsin S dan katepsin D) yang aktif pada otot dari beberapa jenis ikan laut tropis yang komersil di Sulawesi Utara (Epinephelus fuscoguttatus, Caranx ferdau, Lutjanus malabricus, and Katsuwonus pelamis). Ikan-ikan ini sangat bernilai ekonomis dan sangat digemari oleh masyarakat lokal©
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Čekovská, Katarína, Radek Šanda, Kristýna Eliášová, Marcelo Kovačić, Stamatis Zogaris, Anna Maria Pappalardo, Tereza Soukupová und Jasna Vukić. „Population Genetic Diversity of Two Marine Gobies (Gobiiformes: Gobiidae) from the North-Eastern Atlantic and the Mediterranean Sea“. Journal of Marine Science and Engineering 8, Nr. 10 (13.10.2020): 792. http://dx.doi.org/10.3390/jmse8100792.
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Gobies (Gobiiformes: Gobiidae) are the most species-rich family of fishes in general, and the most abundant fish group in the European seas. Nonetheless, our knowledge on many aspects of their biology, including the population genetic diversity, is poor. Although barriers to gene flow are less apparent in the marine environment, the ocean is not a continuous habitat, as has been shown by studies on population genetics of various marine biota. For the first time, European marine goby species which cannot be collected by common fishery techniques were studied. The population genetic structure of two epibenthic species, Gobius geniporus and Gobius cruentatus, from seven localities across their distribution ranges was assessed, using one mitochondrial (cytochrome b) and one nuclear gene (first intron of ribosomal protein gene S7). Our results showed that there is a great diversity of haplotypes of mitochondrial gene cytochrome b in both species at all localities. Global fixation indices (FST) indicated a great differentiation of populations in both studied gobies. Our results did not show a geographic subdivision to individual populations. Instead, the data correspond with the model of migration which allow divergence and recurrent migration from the ancestral population. The estimated migration routes coincide with the main currents in the studied area. This matches well the biology of the studied species, with adults exhibiting only short-distance movements and planktonic larval stages.
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Tsygankov, Vasily Yu, Margarita D. Boyarova, Olga N. Lukyanova und Nadezhda K. Khristoforova. „Hexachlorocyclohexane and DDT in marine organisms from the Bering and the Okhotsk Seas“. Izvestiya TINRO 176, Nr. 1 (30.03.2014): 225–32. http://dx.doi.org/10.26428/1606-9919-2014-176-5-10.
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Organochlorine pesticides (HCHs and DDT) are harmful and toxic substances affected biota. HCHs and DDT are still used as pesticides in the Southern Hemisphere and from there can reach the North Pacific due to atmospheric transfer. Isomers of HCH and DDT and their metabolites were detected in organs of some marine mammals ( Eschrichtius robustus, Odobenus rosmarus divergens ) from the Bering Sea; the maximum concentration was found in the walrus liver (90263 ng/g lipids). To trace these pollutants spreading in the Okhotsk Sea, the seabirds (Pacific gull Larus schistisagus, crested auklet Aethia cristatella, auklet crumb Aethia pusilla, northern fulmar Fulmarus glacialis, and grey petrel Oceanodroma furcata ) and fishes (pink salmon Oncorhynchus gorbusсha and chum salmon Oncorhynchus keta ) were sampled; the pesticides concentration in the birds tissues ranges from 29 ng/g lipids in plume of the fulmar to 16095 ng/g lipids in plume and skin of the auklet and in the salmons tissues - from 220-330 ng/g lipids for the pink salmon to 550-790 ng/g lipids for the chum salmon (both fish species were caught at Kuril Islands).
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Gonzalez, Wilma B. Aleman, Jean M. Self-Trail, W. Burleigh Harris, Jessica Pierson Moore und Kathleen M. Farrell. „Depositional sequence stratigraphy of Turonian to Santonian sediments, Cape Fear arch, North Carolina Coastal Plain, USA“. Stratigraphy 16, Nr. 1 (11.12.2020): 293–314. http://dx.doi.org/10.29041/strat.17.4.293-314.
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ABSTRACT: A new sequence stratigraphic framework for Turonian to Santonian (94-84 Ma) sediments is established using data from the USGS Kure Beach and Elizabethtown cores collected from the Atlantic Coastal Plain of North Carolina (NC). These sediments represent some of the oldest marine units deposited on the southeastern Atlantic Coastal Plain and record the early development of a clastic wedge atop crystalline basement. Sediments were deposited as transitional marginal-marine to marine units in a complex interplay of fluvial, estuarine, and shelf environments. Repetitive lithologies and minimal biostratigraphic control requires an integrated analysis of grain-size data, geophysical logs, biostratigraphy, and 87Sr/86Sr isotopic data to identify systems tracts and establish a sequence stratigraphic framework. From this integrated approach, three Turonian to Santonian sequences in the Elizabethtown core and six in the Kure Beach core are identified. The new sequences from oldest to youngest are Clubhouse II, Fort Fisher I, Fort Fisher II, Collins Creek I, Collins Creek II, Pleasant Creek I, and Pleasant Creek II. Sequences from North Carolina document significant shifts of global and regional sea-level during greenhouse conditions in the early Late Cretaceous. Maximum sea-level rise occurred globally during the early Turonian and is documented from the marine sediments of the Clubhouse II sequence. This sequence is unconformably overlain by terrestrial sediments deposited during a major fall in sea level and maximum progradation of the shoreline, as evidenced by the Fort Fisher I sequence. Global sea-level rise in the Coniacian resulted in the deposition of the Fort Fisher II sequence, which is present only in the Kure Beach core. Local marine circulation and erosion on the shelf is suggested by the absence of the Collins Creek I sequence at Kure Beach; this sequence is present only in the up-dip Elizabethtown core. Activation of a possible buried fault structure along the Cape Fear arch resulted in the formation of a regional depocenter during the late Coniacian to early Santonian and is reflected in the unusual thickness of the Collins Creek II and Pleasant Creek I sequences. The return to a more global sea-level influence occurred in the late Santonian with the deposition of the Pleasant Creek II sequence. A comparison of temporal distribution of sequences in the Elizabethtown and Kure Beach cores to corresponding sequences in New Jersey indicates significant differences in erosional and tectonic processes in the Cape Fear region during the Turonian and Santonian.
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NABIL, WILDAN AHMAD, IMROATUL HABIBAH, ARYOCHEPRIDHO ARYOCHEPRIDHO und TRIJOKO TRIJOKO. „Short Communication: Caught fish species diversity of South Morotai, North Maluku, Indonesia“. Indo Pacific Journal of Ocean Life 2, Nr. 1 (01.06.2018): 33–36. http://dx.doi.org/10.13057/oceanlife/o020105.
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Nabil WA, Habibah I, Aryochepridho, Trijoko. 2018. Caught fish species diversity of South Morotai, North Maluku, Indonesia. Ocean Life 2: 33-36. South Morotai is a part of Morotai Island, an archipelago in eastern Indonesia with high fisheries potential such as fish, sea cucumbers, crabs, shrimp, and algae. Research on fish diversity in South Morotai is needed because there is no sufficient data and information about the potential of Morotai Island marine fisheries. The goal of this research was to collect data on fish species in Morotai, especially South Morotai. This research was conducted by surveys of fish caught by local fishermen in July 2017. Results showed that there were 23 species of fishes belonging to 14 families, with the highest diversity belonging to the Scaridae family (4 species). Serranidae and Acanthuridae each had 3 species identified. Balistidae and Labridae each had 2 species identified. One species was identified from each family of Rachycentridae, Lethrinidae, Lutjanidae, Sphyraenidae, and Mullidae.
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DYLDIN, YURY V., RONALD FRICKE, LUBOMIR HANEL, DANIL S. VOROBIEV, ELENA A. INTERESOVA, VLADIMIR I. ROMANOV und ALEXEI M. ORLOV. „Freshwater and brackish water fishes of Sakhalin Island (Russia) in inland and coastal waters: an annotated checklist with taxonomic comments“. Zootaxa 5065, Nr. 1 (08.11.2021): 1–92. http://dx.doi.org/10.11646/zootaxa.5065.1.1.
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Based on a critical analysis of scientific publications for the last 200 years and on the collected specimens, a complete annotated list of both typical freshwater ichthyofauna of Sakhalin Island, with the inclusion of marine species that can be found in brackish coastal waters, is reported for the first time. The annotated list includes 226 species classified in three classes, 26 orders, 68 families, 29 subfamilies, and 148 genera. For 160 species, information is provided on collection samples deposited in various museums around the world, 36 of which are type specimens. For each species, conservation status (according to IUCN Red List of Threatened Species and the Red Book of the Sakhalin region), zoogeographic characteristics (distribution within Sakhalin Island and globally), abundance and commercial value are given. For a number of species, more detailed information on synonymy and nomenclature is provided. The study area is located in the western North Pacific and includes the entire coast of Sakhalin Island in the Sea of Okhotsk and the northern Sea of Japan, as well as the adjacent Sea of Okhotsk coast of northern Hokkaido, Japan.
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Canino, Michael F., Patrick T. O'Reilly, Lorenz Hauser und Paul Bentzen. „Genetic differentiation in walleye pollock (Theragra chalcogramma) in response to selection at the pantophysin (PanI) locus“. Canadian Journal of Fisheries and Aquatic Sciences 62, Nr. 11 (01.11.2005): 2519–29. http://dx.doi.org/10.1139/f05-155.
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Samples of walleye pollock (Theragra chalcogramma) from the North Pacific Ocean and Bering Sea were screened for variation at the pantophysin (PanI) locus. Global genetic differentiation across samples (FST = 0.038) was considerably greater than reported in previous population studies using allozymes, mtDNA, or microsatellite loci and significantly greater than FST distributions of neutral loci simulated over a large range of locus heterozygosity. PanI allele frequencies varied over a broad latitudinal gradient and were correlated with estimated mean surface temperatures, resulting in the greatest levels of genetic divergence between the northern Bering Sea and the southernmost locations in the temperate Pacific Ocean (Puget Sound, Japan). The discordance between estimates of population differentiation estimated from PanI and other neutral marker classes, both in magnitude and in geographic patterns, could arise from temperature-mediated effects of natural selection over broad geographic scales. Our empirical results suggest that loci subject to directional selection may prove to be useful markers for stock identification in weakly structured marine fishes.
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As’ari, A. H., T. R. Mulyaningsih und S. Yusuf. „Comparative study of mineral element content in fishes from the south and north seas of java island using neutron activation analysis“. Journal of Physics: Conference Series 2193, Nr. 1 (01.02.2022): 012031. http://dx.doi.org/10.1088/1742-6596/2193/1/012031.
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Abstract Fish is an environmental bioindicator and a contributor to the daily intake of mineral elements. The content of mineral elements in fish is influenced by what it eats and its environment. Moreover, based on location, around the north coast of Java there are denser residential and industrial areas compared to around the south coast of Java. In this study, we analyzed the mineral content of fish of the same species originating from the southern and northern seas of Java using neutron activation analysis. Fish samples of the same 11 species were each collected from fish auctions in Pemalang and Garut districts. The samples were washed, and then the meat was taken and dried by the freeze-drying method. The samples were irradiated in the G.A. Siwabessy multi-purpose reactor through the rabbit system then counted using gamma spectrometry. The results obtained as many as 17 mineral elements in fish: Na, K, Mg, Cl, Ca, Br, Fe, Zn, Sr, Al, Cr, Se, Rb, Mn, Co, Hg, and Cs. Statistical test results show that there are various differences (positive covariance on 14 elements, negative covariance on 3 elements) for each element between fish from the South Java Sea and North Sea, which indicates that marine environmental conditions have contributed significantly to changes in mineral content on fish.
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Fondo, Esther N., und Benrick Ogutu. „Sustainable crab fishery for Blue Economy in Kenya“. Aquatic Ecosystem Health & Management 24, Nr. 1 (02.01.2021): 21–26. http://dx.doi.org/10.14321/aehm.024.01.05.
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Abstract Lakes, rivers and oceans provide unique resources and support fisheries and aquaculture worldwide. The fisheries and aquaculture sector of Kenya contributes approximately 0.8% to the country’s GDP. Marine production is about 9 000 tonnes per year. Marine finfish form the bulk of the marine production, while shellfish (e.g. prawns, lobsters and crabs), molluscs (e.g. octopi and squids) are underexploited. The Fishery sector has the potential of about USD 5 billion for the Blue Economy in Kenya. Crab fishery in Kenya is active in some areas of the south and north coast. The crab resources along the Kenyan waters are diverse and a variety of species are edible. The most commonly fished crab by artisanal fishers is the Mangrove Mud Crab Scylla serrata. Semi-commercial and industrial fishers usually have portunid and other deep sea crabs as by-catch in trawl and longline fisheries, which in many cases are unutilized. Exports of live crabs have increased over the years, with exports mainly to Asian countries. Export of frozen crabs started recently. The need to sustainably utilize lake, river and ocean resources is recognized and important in promoting Blue Economy. Sustainable development of crab fishery provides a potential area for the Blue Economy development in Kenya. Research is essential to crab fishery development.
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Bache-Jeffreys, Maisie, Bárbara Lins Caldas de Moraes, Rachel E. Ball, Gui Menezes, Jónbjörn Pálsson, Christophe Pampoulie, Jamie R. Stevens und Andrew M. Griffiths. „Resolving the spatial distributions of Dipturus intermedius and Dipturus batis—the two taxa formerly known as the ‘common skate’“. Environmental Biology of Fishes 104, Nr. 8 (19.07.2021): 923–36. http://dx.doi.org/10.1007/s10641-021-01122-7.
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AbstractBatoid fishes are among the most endangered marine vertebrates, yet conservation efforts have been confounded by incomplete taxonomy. Evidence suggest that the critically endangered ‘common skate’ actually represents two species: the flapper skate (Dipturus intermedius) and the blue skate (Dipturus batis). However, knowledge of the geographic range of these two nominal species is limited. Here, DNA sequencing is used to distinguish these species, allowing their spatial distributions to be clarified. These records were also used as the basis for species distribution modelling, providing the first broad scale models for each species across the Northeast Atlantic. Samples were obtained from Iceland, the UK (specifically Shetland), the North Sea and the Azores. Results suggest that D. batis was commonly distributed in the Western Approaches and Celtic Sea, extending out to Rockall and Iceland. D. intermedius generally appears to be less abundant, but was most frequent around northern Scotland and Ireland, including the northern North Sea, and was also present in Portugal. Two individuals were also identified from seamounts in remote areas of the Atlantic around the Azores, the furthest south and west the species has been found. This supports reports that the flapper skate historically had a much wider distribution (which was also highlighted in the distribution model), emphasising the large scale over which fisheries may have led to extirpations. Furthermore, these Azorean samples shared a unique control region haplotype, highlighting the importance of seamounts in preserving genetic diversity.
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Ackley, S. F., J. L. Bengtson, P. Boveng, M. Castellini, K. L. Daly, S. Jacobs, G. L. Kooyman et al. „A top–down, multidisciplinary study of the structure and function of the pack-ice ecosystem in the eastern Ross Sea, Antarctica“. Polar Record 39, Nr. 3 (26.06.2003): 219–30. http://dx.doi.org/10.1017/s0032247403003115.
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We used a top–down, multidisciplinary approach to examine the physical and biological environment of the pack ice of the eastern Ross Sea (approximately 125–170°W) during the austral summer of 1999/2000 from RVIB Nathaniel B. Palmer and its ship-based helicopters. The approach focused on pack-ice seals while incorporating studies of biotic and abiotic factors that may influence the distribution and abundances of these apex predators in the Ross Sea to yield a holistic understanding of the structure and function of this complex, large marine ecosystem. This research represented the US component of the international Antarctic Pack Ice Seal (APIS) program, which was designed to document the circumpolar distribution and abundance of Antarctic pack-ice seals. The eastern Ross Sea is one of the two major areas in the Southern Ocean where substantial pack ice exists throughout summer. We found that vast multi-year ice floes (>20 km diameter) and smaller floes north of the shore-fast ice front provide a unique habitat for seals and penguins (apex predators) to forage and haul out while molting in late summer. Farther north, more Ross seals were observed than in any previous surveys in the circumpolar pack ice, perhaps because they are attracted to the area in summer to molt on large stable first-year ice floes. Extensive fast ice along the coastline and drifting pack ice in the shelf–slope boundary zone provided haul-out areas for seals and penguins with access to feeding in the coastal shelf region. Distributions of potential prey for seals and penguins varied over the study area, as determined by nets, acoustics, and diving surveys. Antarctic krill (Euphausia superba) were found throughout the survey region, overlapping the distributions of two smaller species, Thysanoëssa macrura (primarily off-shelf) and E. crystallorophias (primarily found on-shelf). In some locations, E. superba occurred at high densities underneath ice floes, where they foraged on the sea-ice microbial community. Two general fish communities, oceanic and shelf, were distinguished. Off-shelf fishes were members of the classic oceanic midwater fish fauna, whereas on-shelf fishes were Antarctic endemics. The abundance of pelagic fishes was relatively low throughout the study area compared with other Southern Ocean ecosystems. In contrast, benthic fish biomass and diversity on-shelf were high (41 species, 6 families). Hydroacoustic analyses indicated that densities of potential prey were highest in the coastal shelf region where large aggregations of euphausiids (primarily E. crystallorophias) and individual juvenile Antarctic silverfish (Pleuragramma antarcticum) occurred.
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Letschert, Jonas, Nicole Stollberg, Henrike Rambo, Alexander Kempf, Jörg Berkenhagen und Vanessa Stelzenmüller. „The uncertain future of the Norway lobster fisheries in the North Sea calls for new management strategies“. ICES Journal of Marine Science 78, Nr. 10 (29.10.2021): 3639–49. http://dx.doi.org/10.1093/icesjms/fsab204.
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Abstract Nephrops (Nephrops norvegicus) is an economically valuable target species in the North Sea. Although individual Nephrops populations are scattered, the crustacean is managed regionally by the European Union (EU). The spatial competition for fisheries in the North Sea is growing especially due to expanding offshore wind farms (OWF) and newly implemented marine protected areas (MPA). Moreover, the Brexit affects the availability of EU fishing quotas and adds to the overall uncertainty EU fishers face. We compare landings and catches to scientifically advised quantities and perform an overlap analysis of fishing grounds with current and future OWFs and MPAs. Furthermore, we explore the German Nephrops fleet using high-resolution spatial fishing effort and catch data. Our results confirm earlier studies showing that Nephrops stocks have been fished above scientific advice. Present OWFs and MPAs marginally overlap with Nephrops fishing grounds, whereas German fishing grounds are covered up to 45% in future scenarios. Co-use strategies with OWFs could mitigate the loss of fishing opportunities. Decreased cod quotas due to Brexit and worse stock conditions, lowers Germany's capability to swap Nephrops quotas with the UK. We support the call for a new management strategy of individual Nephrops populations and the promotion of selective fishing gears.
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Bezhenar, Roman, Kyung Tae Jung, Vladimir Maderich, Stefan Willemsen, Govert de With und Fangli Qiao. „Transfer of radiocaesium from contaminated bottom sediments to marine organisms through benthic food chains in post-Fukushima and post-Chernobyl periods“. Biogeosciences 13, Nr. 10 (23.05.2016): 3021–34. http://dx.doi.org/10.5194/bg-13-3021-2016.
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Abstract. After the earthquake and tsunami on 11 March 2011 damaged the Fukushima Dai-ichi Nuclear Power Plant (FDNPP), an accidental release of a large amount of radioactive isotopes into both the air and the ocean occurred. Measurements provided by the Japanese agencies over the past 5 years show that elevated concentrations of 137Cs still remain in sediments, benthic organisms, and demersal fishes in the coastal zone around the FDNPP. These observations indicate that there are 137Cs transfer pathways from bottom sediments to the marine organisms. To describe the transfer quantitatively, the dynamic food chain biological uptake model of radionuclides (BURN) has been extended to include benthic marine organisms. The extended model takes into account both pelagic and benthic marine organisms grouped into several classes based on their trophic level and type of species: phytoplankton, zooplankton, and fishes (two types: piscivorous and non-piscivorous) for the pelagic food chain; deposit-feeding invertebrates, demersal fishes fed by benthic invertebrates, and bottom omnivorous predators for the benthic food chain; crustaceans, mollusks, and coastal predators feeding on both pelagic and benthic organisms. Bottom invertebrates ingest organic parts of bottom sediments with adsorbed radionuclides which then migrate up through the food chain. All organisms take radionuclides directly from water as well as food. The model was implemented into the compartment model POSEIDON-R and applied to the north-western Pacific for the period of 1945–2010, and then for the period of 2011–2020 to assess the radiological consequences of 137Cs released due to the FDNPP accident. The model simulations for activity concentrations of 137Cs in both pelagic and benthic organisms in the coastal area around the FDNPP agree well with measurements for the period of 2011–2015. The decrease constant in the fitted exponential function of simulated concentration for the deposit-feeding invertebrates (0.45 yr−1) is close to the observed decrease constant in sediments (0.44 yr−1). These results strongly indicate that the gradual decrease of activity in demersal fish (decrease constant is 0.46 yr−1) is caused by the transfer of activity from organic matter deposited in bottom sediment through the deposit-feeding invertebrates. The estimated model transfer coefficient from bulk sediment to demersal fish in the model for 2012–2020 (0.13) is larger than that to the deposit-feeding invertebrates (0.07). In addition, the transfer of 137Cs through food webs for the period of 1945–2020 has been modelled for the Baltic Sea contaminated due to global fallout and from the Chernobyl accident. The model simulation results obtained with generic parameters are also in good agreement with available measurements in the Baltic Sea. Unlike the open coastal system where the FDNPP is located, the dynamics of radionuclide transfer in the Baltic Sea reach a quasi-steady state due to the slow rate in water mass exchange in this semi-enclosed basin. Obtained results indicate a substantial contribution of the benthic food chain in the long-term transfer of 137Cs from contaminated bottom sediments to marine organisms and the potential application of a generic model in different regions of the world's oceans.
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Matahelemual, Godfried Junio Sebastian, Agung Budi Harto und Tri Muji Susantoro. „Oil Spill Detection using Sentinel-1 Multitemporal Data in Offshore Karawang“. Scientific Contributions Oil and Gas 43, Nr. 2 (31.08.2020): 69–79. http://dx.doi.org/10.29017/scog.43.2.522.
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Oil spill is a serious problem that could lead to economic and ecological losses, both in the short and long term. On July 12, 2019, there occurred an oil leakage around YYA-1 oil platform of Pertamina Hulu Energi Offshore North West Java (PHE ONWJ), located off the northern coast of Karawang, Java Sea. This incident has caused the death of fishes and marine animals, damage to coral reefs, mangroves, and seagrass beds, and several health problems of coastal communities. Therefore, it is necessary to map and monitor oil spills, so that actions can be taken to prevent the spread of oil spills. This study aims to map the distribution of oil spills in Karawang sea using multitemporal Sentinel-1 data from July to September 2019. The detection is carried out using the adaptive thresholding algorithm combined with manual interpretation. The result shows that the oil spills spread around Karawang sea from YYA-1 platform to Sedari Village and there are oil spills spreading from the Central Plant F/S platform. The oil spills tend to shift westward from July to September 2019. This shifting is supposed to be influenced by current and wave factors that were dominant moving westward at that time. Based on data processing, it was found that the oil spill area from July to September was respectively 24.79 km2, 20.05 km2, and 27.12 km2.
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Bastos, GC, und M. Petrere Jr. „Small-scale marine fisheries in the municipal district of Florianópolis, Santa Catarina, Brazil“. Brazilian Journal of Biology 70, Nr. 4 (November 2010): 947–53. http://dx.doi.org/10.1590/s1519-69842010000500005.
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The objective of this paper is to describe the main characteristics of small-scale marine fisheries in the municipal district of Florianópolis (SC), the capital city of the state of Santa Catarina. We give information about the most captured species, the fishing fleet and fishing gear used. The dynamics of the activity is described, considering the kind of operation of the boats, alongside post-capture procedures. The analyses were accomplished in two types of fishing communities: the one composed of fishers that fish in bays (North and South) and those who fish in the open sea. Numeric differences were observed among these two fishing areas, indicating the existence of two different fleets operating in the area. Differences between the two fishing areas were detected, considering the species caught, the harvest time and the fishing gear used. The open sea fishers have boats with dimensions, engine power, number of crew and fuel consumption numerically higher than those working in bays, indicating the existence of two distinct fleets operating in the region.
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Frank, Kenneth T., Brian Petrie, William C. Leggett und Daniel G. Boyce. „Exploitation drives an ontogenetic-like deepening in marine fish“. Proceedings of the National Academy of Sciences 115, Nr. 25 (04.06.2018): 6422–27. http://dx.doi.org/10.1073/pnas.1802096115.
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Virtually all studies reporting deepening with increasing size or age by fishes involve commercially harvested species. Studies of North Sea plaice in the early 1900s first documented this phenomenon (named Heincke’s law); it occurred at a time of intensive harvesting and rapid technological changes in fishing methods. The possibility that this deepening might be the result of harvesting has never been evaluated. Instead, age- or size-related deepening have been credited to interactions between density-dependent food resources and density-independent environmental factors. Recently, time-dependent depth variations have been ascribed to ocean warming. We use a model, initialized from observations of Atlantic cod (Gadus morhua) on the eastern Scotian Shelf, where an age-dependent deepening of ∼60 m was observed, to assess the effect of size- and depth-selective exploitation on fish distribution. Exploitation restricted to the upper 80 m can account for ∼72% of the observed deepening; by extending exploitation to 120 m, all of the deepening can be accounted for. In the absence of fishing, the model indicated no age-related deepening. Observations of depth distributions of older cod during a moratorium on fishing supported this prediction; however, younger cod exhibited low-amplitude deepening (10–15 m) suggestive of an ontogenetic response. The implications of these findings are manifold, particularly as they relate to hypotheses advanced to explain the ecological and evolutionary basis for ontogenetic deepening and to recent calls for the adoption of evidence of species deepening as a biotic indicator or “footprint” of warming seas.
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Goldsworthy, DS, BJ Saunders, JRC Parker und ES Harvey. „Spatial assemblage structure of shallow-water reef fish in Southwest Australia“. Marine Ecology Progress Series 649 (10.09.2020): 125–40. http://dx.doi.org/10.3354/meps13445.
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Bioregional categorisation of the Australian marine environment is essential to conserve and manage entire ecosystems, including the biota and associated habitats. It is important that these regions are optimally positioned to effectively plan for the protection of distinct assemblages. Recent climatic variation and changes to the marine environment in Southwest Australia (SWA) have resulted in shifts in species ranges and changes to the composition of marine assemblages. The goal of this study was to determine if the current bioregionalisation of SWA accurately represents the present distribution of shallow-water reef fishes across 2000 km of its subtropical and temperate coastline. Data was collected in 2015 using diver-operated underwater stereo-video surveys from 7 regions between Port Gregory (north of Geraldton) to the east of Esperance. This study indicated that (1) the shallow-water reef fish of SWA formed 4 distinct assemblages along the coast: one Midwestern, one Central and 2 Southern Assemblages; (2) differences between these fish assemblages were primarily driven by sea surface temperature, Ecklonia radiata cover, non-E. radiata (canopy) cover, understorey algae cover, reef type and reef height; and (3) each of the 4 assemblages were characterised by a high number of short-range Australian and Western Australian endemic species. The findings from this study suggest that 4, rather than the existing 3 bioregions would more effectively capture the shallow-water reef fish assemblage patterns, with boundaries having shifted southwards likely associated with ocean warming.
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Tesakov, Alexey S., Vadim V. Titov, Alexandra N. Simakova, Pavel D. Frolov, Elena V. Syromyatnikova, Sergey V. Kurshakov, Natalia V. Volkova et al. „Late Miocene (Early Turolian) vertebrate faunas and associated biotic record of the Northern Caucasus: Geology, palaeoenvironment, biochronology“. Fossil Imprint 73, Nr. 3-4 (01.12.2017): 383–444. http://dx.doi.org/10.2478/if-2017-0021.
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Abstract Late Miocene continental deposits overlying the Khersonian marine sediments near the city of Maikop bordering the Belaya River (North Caucasus) yielded a diverse biotic record including palynology, ostracods, fresh-water and terrestrial molluscs, fishes, amphibians and reptiles, birds, and mammals. The obtained data indicate predominantly wooded landscapes along the banks of a large fresh-water estuarine or lagoonal basin with occasional connection with the sea. The basin existed in a warm temperate to subtropical climate with a high humidity and an estimated mean annual precipitation above 800 mm. The mammalian assemblage with Hipparion spp., Alilepus sp., Paraglirulus schultzi, Eozapus intermedius, Parapodemus lugdunensis, Collimys caucasicus sp. nov., Neocricetodon cf. progressus, etc. is referable to the early Turolian, MN 11. The data regarding composition and stage of evolution of the small mammal content combined with mostly normal polarity of the fossiliferous deposits, and the age estimates of the upper Khersonian boundary as between 8.6 and 7.9 Ma indicate a plausible correlation with Chron C4n and an age range between 8.1–7.6 Ma.
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Chikurova, E. A., A. M. Orlov, D. M. Shchepetov und S. Yu Orlova. „Separated by Space and Time but United by Kinship: Phylogeographical and Phylogenetic History of Two Species of Eleginus (Gadidae) Based on the Polymorphism of Cyt b Mitochondrial DNA Gene“. Вопросы ихтиологии 63, Nr. 2 (01.03.2023): 131. http://dx.doi.org/10.31857/s0042875223020042.
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Fishes of the genus Eleginus (Gadidae) are typical representatives of the ichthyofauna of the Northern Hemisphere; they play an important trophic role in the marine ecosystems of the Arctic and North Pacific and serve as targets of commercial and artisanal coastal fishing in many areas of the Russian North and Far East, as well as in areas of the coast of Alaska and northern Japan. The level of knowledge about the intraspecific organization of representatives of the genus Eleginus that is necessary for the rational exploitation of their stocks remains insufficient and their interspecific relationships have so far been analyzed using limited materials. This paper presents the first study of the interspecific relationships and intraspecific structure of navaga (E. nawaga) and saffron cod (E. gracilis) using a large-scale material (986 specimens in 29 samples from most of the species ranges) based on analysis of the polymorphism of mtDNA gene Cyt b. It is shown that they are independent, genetically differentiated species and their comparison with representatives of the genus Microgadus indicates that both species of the genus Eleginus might originate from a common ancestor close to M. proximus, while the divergence in the genus Microgadus occurred much earlier. Data on the haplotypic composition of saffron cod samples inhabiting areas from the Peter the Great Bay to Alaska waters and navaga samples inhabiting areas from the White Sea to the Ob Bay of the Kara Sea are given, which makes it possible to consider the phylogeographic history of both species and their intraspecific organization within the studied areas. Three groups can be distinguished for saffron cod: (1) Pacific–Japanese–Sakhalin group, (2) Chukchi–Bering seas group, and (3) intermediate group, which includes samples from the Sea of Okhotsk and waters of the northern Kurils.
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Harington, C. Richard. „Quaternary Vertebrates of Québec: a Summary“. Géographie physique et Quaternaire 57, Nr. 1 (10.02.2005): 85–94. http://dx.doi.org/10.7202/010332ar.
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Abstract The only representative of the extinct North American megafauna known from Québec is an American mastodon from Pointe de Chambord, Lac-Saint-Jean. Marine mammals have played a prominent part in our knowledge of the Quaternary vertebrates of Québec since Per Kalm was informed of a whale skeleton found inland from the St. Lawrence River about 1749. Five species of whales particularly adapted to inshore conditions have been reported from Late-glacial deposits of Champlain Sea age. The bones represent mainly white whales, but also narwhals, harbour porpoise, humpback, common finback and bowhead whales. Seals (ringed, harp, bearded and harbour) have also been discovered, and walrus remains are known from Sainte-Julienne-de-Montcalm and Saint-Nicolas. Sandpits at Saint-Nicolas (bottom-dwelling fishes, seabirds, ringed seal and white whale) and Saint-Césaire (fish, eider duck, ringed seal and white whale) have yielded important Champlain Sea vertebrate fossils, as well as paleoenvironmental information. Many well-preserved vertebrate remains have been found in calcareous nodules from Eardley and Breckenridge in the Gatineau area. Perhaps cave faunas will become increasingly important in sorting out the Quaternary vertebrate faunal sequence in Québec. The finds from caves near Saint-Elzéar and La Rédemption in Gaspésie, as well as Mine and Laflèche caves in the Gatineau region have already yielded fascinating insights. A list of radiocarbon dates on Quaternary vertebrates from Québec is provided.
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Kubilius, Rokas, und Egil Ona. „Target strength and tilt-angle distribution of the lesser sandeel (Ammodytes marinus)“. ICES Journal of Marine Science 69, Nr. 6 (01.07.2012): 1099–107. http://dx.doi.org/10.1093/icesjms/fss093.
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Abstract Kubilius, R., and Ona, E. 2012. Target strength and tilt-angle distribution of lesser sandeel (Ammodytes marinus) – ICES Journal of Marine Science, 69: 1099–1107. North Sea stocks of lesser sandeel have recently become depleted, and improved methods for abundance estimation are sought. This paper focuses on the acoustic target strength (TS) and orientation of sandeel, measured simultaneously in several field experiments. A specially designed cubic cage, fitted with an echosounder and a video camera, was lowered onto the sea bottom, trapping wild sandeel inside. Methods for manually selecting valid echotraces from individual sandeel are described. Scattered mean TS values from several experiments are reported. These are, in spite of the observed variability, summarized in a TS–fish length (cm) relationship as TS = 20logL – 93.1 (dB) at 200 kHz. We believe that the accuracy of the relationship may still be debated; incorporating larger uncertainty in the overall mean TS will increase the total uncertainty of the stock biomass estimate from sandeel acoustic surveys. This uncertainty is now, using standard narrow-beam echosounders, dominated by the fish patchiness relative to the survey coverage. Results from pilot investigations of the sandeel swimming orientation using video cameras are also presented, showing that sandeel usually has an anguilliform swimming pattern with substantial positive (head-up) tilt. The spread of the tilt-angle distribution is also larger than for more neutrally buoyant fishes.
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Fardilah, Muhammad Fajar Fajri, Domu Simbolon, Muhammad Fedi Alfiadi Sondita, Tengku Ersti Yulika Sari und Heri Setiawan. „SPATIAL-TEMPORAL DISTRIBUTION OF NARROW-BARRED SPANISH MACKEREL (Scomberomorus commerson) FISHING GROUNDS IN RIAU ARCHIPELAGO WATERS, INDONESIA“. Marine Fisheries : Journal of Marine Fisheries Technology and Management 15, Nr. 1 (21.05.2024): 69–82. http://dx.doi.org/10.29244/jmf.v15i1.51908.
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Narrow-barred Spanish mackerel (Scomberomorus commerson) is an exportable fish captured by gillnet fishing fleets from Bintan Regency. The fleets are operated in the Riau Archipelago waters but information on their activities is limited. Such information is important to the institution the Agency for Marine and Fisheries Affairs of Archipelagic Riau Province for ensuring the sustainability of the fisheries from both economic and biological perspectives. This study aims to determine the spatial-temporal distributions of the mackerel fishing grounds along the year with reference to the capture data, sea surface temperatures, chlorophyll-a concentrations, and salinities in the last 4 months of 2022. This study analyzed data from a fish export company, the PSDKP office at Tanjungpinang, Bintan, interviews of fishers affiliated with 44 fishing boat samples, and satellite-based marine data. Analysis on the monthly fishing productivity and optimum marine conditions for the mackerels were carried out to determine prospects of five recognized fishing grounds. Besides Lingga Islands, the fishing grounds are highly prospective from August to November. The longest fishing seasons are expected around Bangka Island (11 months). The spatial and temporal patterns show that the north-south-north shifts in fishing grounds that are associated with regional climates, i.e., monsoon winds.
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Wright, P. J. „Otolith Microstructure of the Lesser Sandeel, Ammodytes Marinus“. Journal of the Marine Biological Association of the United Kingdom 73, Nr. 1 (Februar 1993): 245–48. http://dx.doi.org/10.1017/s0025315400032793.
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Daily increments were demonstrated in the sagittae of the lesser sandeel, Ammodytes marinus, maintained in outdoor enclosures. Daily increment formation was also inferred for wild sandeels from an analysis of changes in age composition within a series of field samples. A comparison between sagitta microstructure and morphological development of larval and juvenile sandeels indicated that the first sagitta increment was formed around the time of hatching. Yolk-sac absorption and larval metamorphosis were accompanied by changes in otolith microstructure.The lesser sandeel, Ammodytes marinus (Raitt), is important as a prey item for many species of fish, seabirds and marine mammals (Furness, 1990) and supports major fisheries in the North Sea (Anon., 1991). However, little is known about the ecological processes affecting year-class strength in this species. Otolith microstructure has been demonstrated to be a potentially useful tool for investigating early survivorship in fishes, since otoliths may provide a chronological record of early growth and life-history events (see Campana & Neilson, 1985). This paper examines the usefulness of otolith microstructure for studies of sandeel growth, from investigations of increment periodicity and a comparison between otolith microstructure and morphological development.
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Daewel, Ute, Myron A. Peck und Corinna Schrum. „Life history strategy and impacts of environmental variability on early life stages of two marine fishes in the North Sea: an individual-based modelling approach“. Canadian Journal of Fisheries and Aquatic Sciences 68, Nr. 3 (März 2011): 426–43. http://dx.doi.org/10.1139/f10-164.
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We employed a suite of coupled models to estimate the influence of environmental variability in the North Sea on early life stages of sprat ( Sprattus sprattus ), a small pelagic clupeid, and Atlantic cod ( Gadus morhua ), a demersal gadoid. Environmentally driven changes in bottom-up processes were projected to impact the survival and growth of eggs and larvae of these marine fish species in markedly different ways. We utilized a spatially explicit, individual-based model (IBM) to estimate larval fish survival and a 3D ecosystem model (ECOSMO) to provide variable prey fields. The model was applied to each of 3 years (1990, 1992, 1996) specifically characterized by interannual differences in water temperature in late winter and spring. Our results indicated that an important mechanism connecting environmental factors to larval fish survival was the match–mismatch dynamics of first-feeding larvae and their prey, which was species-specific because of (i) differences in the timing and locations of spawning, (ii) the duration of endogenously feeding life stages, and (iii) prey thresholds required for larval survival. Differences in transport processes also played an important role for the potential survival of larvae of both species.
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Nielsen, Einar E., Peter H. Nielsen, Dorte Meldrup und Michael M. Hansen. „Genetic population structure of turbot (Scophthalmus maximus L.) supports the presence of multiple hybrid zones for marine fishes in the transition zone between the Baltic Sea and the North Sea“. Molecular Ecology 13, Nr. 3 (März 2004): 585–95. http://dx.doi.org/10.1046/j.1365-294x.2004.02097.x.
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Yalindua, Fione Yukita, Teguh Peristiwady und Putri Saphira Ibrahim. „Update on New Species and Record of Fishes in the Coral Triangle Region for the Last 10 Years (2008-2019)“. Journal of Tropical Biodiversity and Biotechnology 6, Nr. 1 (10.03.2021): 59230. http://dx.doi.org/10.22146/jtbb.59230.
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Updated data is an essential requirement for carrying out research, planning, and policy briefs. The Coral reef triangle region is one of the areas with the highest diversity of marine biota and the discovery of new species in this area are increasing every year, much of this information is already available. However, most of the data is not available per region and is still scattered. This study aims to create a checklist and assessment of new species and a new record of fishes from this region over the last ten years based on several aspects, including species composition, pattern of distribution, endemicity, and depth using every source of the report and secondary literature data. The current new species and a new record of fish in the last decades combined consists of 360 species (268 new species and 92 new records). The most speciose group of family dominated by Gobiidae (93), followed by Labridae, Pomacentridae and Serranidae (18), Apogonidae (17), Dasyatidae (15), and the rest were ranged from 1-9 species per family. More than half of new species and new records are found in Indonesia, followed by the Philippines, Papua New Guinea, and Solomon Island. The result shows that cryptobenthic Families especially Gobiidae from genus Trimma and eviota are dominated the trend of new species and new record discovery and it is expected to rise over time while there will also be an emergence of some possibly new endemic species from major and rare families from the eastern part of Indonesia (West Papua and Papua New Guinea). Thus, the eastern part of Indonesia (Papua, Maluku, Aru Sea, and Papua New Guinea) and the northern part of Indonesia (North Sulawesi and Philippine) are suitable for exploration for marine biodiversity discovery research in the future.
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Schultze, Hans-Peter. „The Upper Devonian fish locality of Miguasha, Quebec, Canada“. Paleontological Society Special Publications 6 (1992): 262. http://dx.doi.org/10.1017/s2475262200008224.
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At Miguasha, Québec (earlier referred to as Scaumenac Bay), the Escuminac Formation, lowermost Upper Devonian, yields an abundant and diverse fish fauna and flora. Both vertebrates and plant fossils from the locality are reknowned throughout the world. The excellent preservation, including that of endocranial anatomy, enabled Jarvik to describe and illustrate fine anatomical details of the osteolepiform Eusthenopteron. That gives the wrong impression that Miguasha is throughout the Escuminac Formation an outstanding Conservat Fossil-Lagerstätte.The cliffs at Miguasha bear fishes throughout the approximately 120 m thick Escuminac Formation. The lithology of the sediments changes throughout the sequence. Close to the base of the formation, acanthodians and anaspid-like agnathans occur in laminites, sometimes hundreds on one horizon. In these laminites, soft tissue preservation may occur (anapsid-like agnathans), and diagenetic transformations of acanthodians into organic substance led to misinterprations and recognition of the “larval chordate Scaumenella.” Most common within the sequence are limy concretions with different fish fossils, most commonly Bothriolepis. Three-dimensionally preserved fishes occur within the sandstone-siltstones and sometimes within the concretions. In all these cases, dermal bone is preserved, and in few cases chondral bone too, as in Eusthenopteron. One can characterize these fossiliferous sections of the Escuminac Formation as Concentration Fossil-Lagerstätte, whereas the laminites are Conservat Fossil-Lagerstätten.The depositional environment was previously interpreted as an intermontaneous basin, based on tectonic and paleogeographic position. More recent paleogeographic reconstructions show a connection with Scottish deposits and to marine deposits in the present day North Sea. The lack of invertebrates and of marine plant remains, and the occurrence of vertebrates in other localities were used as additional indicators for freshwater deposition.The sedimentological features are ambiguous, the turbidites, such as those found at Miguasha, can occur in marine or large freshwater bodies. Conchostracans occur, sometimes in the thousands on a single plane, in the basal part of the Escuminac Formation. They occur today in freshwater or brackish environments; the same species as the one in the Escuminac Formation is reported from lower Upper Devonian marine deposits in the Baltic (Koknese, Latvia). A detailed comparison of the fish fauna with other lower Upper Devonian fish faunas indicates a coastal marine environment. That is supported by rare trace fossils and by different chemical analyses of the sediments and 87S/86S analysis of Bothriolepis bones.In conclusion, earlier interpretations of the paleogeographic position of the Escuminac Formation at Miguasha and chemical and faunal indicators contradict each other in the interpretation of the paleoenvironment of the formation.
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Pieruccini, Pierluigi, Claudio Di Celma, Federico Di Rita, Donatella Magri, Giorgio Carnevale, Piero Farabollini, Luca Ragaini und Mauro Caffau. „Sedimentology, faunal content and pollen record of Middle Pleistocene palustrine and lagoonal sediments from the Peri-Adriatic basin, Abruzzi, eastern central Italy“. Quaternary Research 86, Nr. 3 (November 2016): 359–72. http://dx.doi.org/10.1016/j.yqres.2016.08.003.
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AbstractA 25 m-thick outcrop section exposed at Torre Mucchia, on the sea-cliff north of Ortona, eastern central Italy, comprises a rare Middle Pleistocene succession of shallow-water and paralic sediments along the western Adriatic Sea. An integrated study of the section, including facies and microfacies analyses, and characterization of paleobiological associations (mollusks, fishes, ostracods, foraminifers and pollen), enable a detailed reconstruction of the paleoenvironmental and paleoclimatic conditions during deposition. The shallow-water deposits include a transgressive, deepening- and fining-upward shoreface to offshore-transition facies succession overlain by a regressive shoreface-foreshore sandstone body with an erosive base and a rooted and pedogenically altered horizon at the top that imply deposition during sea-level fall. This forced regressive unit is overlain by paralic strata forming a transgressive succession comprising palustrine carbonates and back-barrier lagoonal mudstones. The palustrine carbonates exhibit some of the typical features encountered in palustrine limestones deposited within seasonal freshwater wetlands (marl prairies). Following the sea-level rising trend, the freshwater marshes were abruptly replaced by a barrier-lagoon system that allowed deposition of the overlying mud-rich unit. Within these deposits, the faunal assemblages are consistent with a low-energy brackish environment characterized by a relatively high degree of confinement. The pollen record documents the development of open forest vegetation dominated by Pinus and accompanied by a number of mesophilous and thermophilous tree taxa, whose composition supports a tentative correlation with Marine Oxygen Isotope Stage 17. The new pollen record from Torre Mucchia improves our understanding of the vegetation development in the Italian Peninsula during the Middle Pleistocene and sheds new light on the role played by the most marked glacial periods in determining the history of tree taxa.
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Steneck, Robert S., Michael H. Graham, Bruce J. Bourque, Debbie Corbett, Jon M. Erlandson, James A. Estes und Mia J. Tegner. „Kelp forest ecosystems: biodiversity, stability, resilience and future“. Environmental Conservation 29, Nr. 4 (Dezember 2002): 436–59. http://dx.doi.org/10.1017/s0376892902000322.
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Kelp forests are phyletically diverse, structurally complex and highly productive components of coldwater rocky marine coastlines. This paper reviews the conditions in which kelp forests develop globally and where, why and at what rate they become deforested. The ecology and long archaeological history of kelp forests are examined through case studies from southern California, the Aleutian Islands and the western North Atlantic, well-studied locations that represent the widest possible range in kelp forest biodiversity. Global distribution of kelp forests is physiologically constrained by light at high latitudes and by nutrients, warm temperatures and other macrophytes at low latitudes. Within mid-latitude belts (roughly 40–60° latitude in both hemispheres) well-developed kelp forests are most threatened by herbivory, usually from sea urchins. Overfishing and extirpation of highly valued vertebrate apex predators often triggered herbivore population increases, leading to widespread kelp deforestation. Such deforestations have the most profound and lasting impacts on species-depauperate systems, such as those in Alaska and the western North Atlantic. Globally urchin-induced deforestation has been increasing over the past 2–3 decades. Continued fishing down of coastal food webs has resulted in shifting harvesting targets from apex predators to their invertebrate prey, including kelp-grazing herbivores. The recent global expansion of sea urchin harvesting has led to the widespread extirpation of this herbivore, and kelp forests have returned in some locations but, for the first time, these forests are devoid of vertebrate apex predators. In the western North Atlantic, large predatory crabs have recently filled this void and they have become the new apex predator in this system. Similar shifts from fish- to crab-dominance may have occurred in coastal zones of the United Kingdom and Japan, where large predatory finfish were extirpated long ago. Three North American case studies of kelp forests were examined to determine their long history with humans and project the status of future kelp forests to the year 2025. Fishing impacts on kelp forest systems have been both profound and much longer in duration than previously thought. Archaeological data suggest that coastal peoples exploited kelp forest organisms for thousands of years, occasionally resulting in localized losses of apex predators, outbreaks of sea urchin populations and probably small-scale deforestation. Over the past two centuries, commercial exploitation for export led to the extirpation of sea urchin predators, such as the sea otter in the North Pacific and predatory fishes like the cod in the North Atlantic. The large-scale removal of predators for export markets increased sea urchin abundances and promoted the decline of kelp forests over vast areas. Despite southern California having one of the longest known associations with coastal kelp forests, widespread deforestation is rare. It is possible that functional redundancies among predators and herbivores make this most diverse system most stable. Such biodiverse kelp forests may also resist invasion from non-native species. In the species-depauperate western North Atlantic, introduced algal competitors carpet the benthos and threaten future kelp dominance. There, other non-native herbivores and predators have become established and dominant components of this system. Climate changes have had measurable impacts on kelp forest ecosystems and efforts to control the emission of greenhouse gasses should be a global priority. However, overfishing appears to be the greatest manageable threat to kelp forest ecosystems over the 2025 time horizon. Management should focus on minimizing fishing impacts and restoring populations of functionally important species in these systems.
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Andrews, Allen H., Daria Siciliano, Donald C. Potts, Edward E. DeMartini und Stephannie Covarrubias. „Bomb Radiocarbon and the Hawaiian Archipelago: Coral, Otoliths, and Seawater“. Radiocarbon 58, Nr. 3 (17.05.2016): 531–48. http://dx.doi.org/10.1017/rdc.2016.32.
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AbstractCorals of the Hawaiian Archipelago are well situated in the North Pacific Gyre (NPG) to record how bomb-produced radiocarbon has been sequestered and transported by the sea. While this signal can be traced accurately through time in reef-building corals and used to infer oceanographic processes and determine the ages of marine organisms, a comprehensive and validated record has been lacking for the Hawaiian Archipelago. In this study, a coral core from Kure Atoll in the northwestern Hawaiian Islands was used to create a high-resolution bomb 14C record for the years 1939–2002, and was then used with other 14C measurements in fish otoliths and seawater to explore differences and similarities in the bomb 14C signal throughout the Hawaiian Archipelago. The Kure Atoll sample series produced a well-defined bomb 14C curve that, with some exceptions, was similar to other coral 14C records from the Hawaiian Archipelago. Subtle differences in the coral 14C records across the region may be explained by the large-scale ocean circulation patterns and decadal cycles of the NPG. The most rapid increase of 14C, in the 1950s and 1960s, showed similar timing across the Hawaiian Archipelago and provides a robust basis for use of bomb 14C dating to obtain high-precision age determinations of marine organisms. Reference otoliths of juvenile fish demonstrated the use of the post-peak 14C decline period as a viable reference in the age validation of younger and more recently collected fishes, and effectively extended the utility of bomb 14C dating to the latest 30 yr.
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Choi, ES, LE Furtado und RS Burton. „Spatial and temporal variation in the species diversity of coastal California fish eggs“. Marine Ecology Progress Series 669 (08.07.2021): 139–49. http://dx.doi.org/10.3354/meps13723.
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Ichthyoplankton studies can be used to assess the abundance, distribution, and reproductive activity of marine fishes, but few studies have monitored spawning activity at inshore sites. This study utilized weekly plankton sampling to construct a year-long time series of fish spawning at 6 pier sites along the California coast—Santa Cruz, San Luis Obispo, Santa Barbara, Santa Monica, Newport Beach, and La Jolla; sampling at the La Jolla site continues ongoing monitoring initiated in 2012. Fish eggs were sorted from the collected plankton and identified to species level using DNA barcoding of the COI and 16S genes. While only one year of data has been collected from 5 of the sites, the 2 sites north of Point Conception show markedly reduced diversity compared to the southern sites. Although the species observed reflect the local environment of each site, this pattern of reduced diversity at the northern sites is consistent with the well-documented decline in species richness with latitude along the California coast. The 7-year time series from La Jolla has revealed that spawning activity varies greatly among years, both in terms of egg production and species diversity, with a continuing trend of highest egg numbers in years with colder average winter sea surface temperature.
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Kirby, Richard R., und Gregory Beaugrand. „Trophic amplification of climate warming“. Proceedings of the Royal Society B: Biological Sciences 276, Nr. 1676 (09.09.2009): 4095–103. http://dx.doi.org/10.1098/rspb.2009.1320.
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Ecosystems can alternate suddenly between contrasting persistent states due to internal processes or external drivers. It is important to understand the mechanisms by which these shifts occur, especially in exploited ecosystems. There have been several abrupt marine ecosystem shifts attributed either to fishing, recent climate change or a combination of these two drivers. We show that temperature has been an important driver of the trophodynamics of the North Sea, a heavily fished marine ecosystem, for nearly 50 years and that a recent pronounced change in temperature established a new ecosystem dynamic regime through a series of internal mechanisms. Using an end-to-end ecosystem approach that included primary producers, primary, secondary and tertiary consumers, and detritivores, we found that temperature modified the relationships among species through nonlinearities in the ecosystem involving ecological thresholds and trophic amplifications. Trophic amplification provides an alternative mechanism to positive feedback to drive an ecosystem towards a new dynamic regime, which in this case favours jellyfish in the plankton and decapods and detritivores in the benthos. Although overfishing is often held responsible for marine ecosystem degeneration, temperature can clearly bring about similar effects. Our results are relevant to ecosystem-based fisheries management (EBFM), seen as the way forward to manage exploited marine ecosystems.