Paralarval and juvenile cephalopods within warm-core eddies in the North Atlantic

2020 ◽  
Vol 96 (2) ◽  
pp. 235-262
Author(s):  
Morag Taite ◽  
Michael Vecchione ◽  
Sheena Fennell ◽  
Louise A Allcock
Keyword(s):  
North Atlantic ◽  
Mesoscale Eddies ◽  
Molecular Evidence ◽  
Scattering Layer ◽  
The North ◽  
Warm Core ◽  
The Family ◽  
Deep Scattering Layer ◽  
Abundance And Diversity ◽  
Abundance And Distribution

Many descriptions of paralarval and juvenile cephalopods are poor. By using DNA barcoding, a global bioidentification system for animals, along with morphological investigation, we can confirm species identifications. We have a better chance of eliminating misidentifications and, therefore, documenting the correct abundance and distribution of cephalopods within an area by combining morphological and molecular evidence. The central objectives of this study are to: (1) compare morphological vs molecular identification of cephalopods and (2) determine the occurrence of cephalopods within the deep scattering layer (DSL) within warm core eddies. The specimens reported here were collected between 2014 and 2016 during three transatlantic cruises from Galway, Ireland to St John's, Newfoundland, with a focus on assemblages in warm-core mesoscale eddies on the western part of the transect. Samples were collected from the DSL at multiple stations across mesoscale eddies. In total, 301 cephalopods belonging to 29 species were collected. Not only does our study increase the knowledge of abundance and diversity of pelagic cephalopods in this area, but it also provides sequences for species for which no comparative sequences were previously available. By examining the match/mismatch between morphological and molecular identifications, we highlight a need for revisions in some taxonomic groupings such as the family Cranchiidae.

scholarly journals New Miocene Monachinae from the Western Shore of the Chesapeake Bay (Maryland, USA)

2017 ◽  
Vol 51 (3) ◽  
pp. 221-242 ◽  
Author(s):  
S. J. Rahmat ◽  
I. A. Koretsky ◽  
J. E. Osborne ◽  
A. A. Alford
Keyword(s):  
North Atlantic ◽  
Fish Fauna ◽  
Eastern United States ◽  
Aquatic Life ◽  
Low Salinity ◽  
The North ◽  
Early Oligocene ◽  
The Family ◽  
Western Shore ◽  
The North Atlantic

Abstract The Family Phocidae includes four subfamilies (Phocinae, Monachinae, Cystophorinae, and Devinophocinae) consisting of mediumto large-sized mammals that possess distinctive adaptations to semi-aquatic life. In the Miocene of the Chesapeake Group, only two subfamilies of the Family Phocidae were identified: Phocinae and Monachinae. Leptophoca, a representative of the subfamily Phocinae, appears on the eastern shore of the North Atlantic around 16 million years ago. Recently, two new monachine species, the larger Terranectes magnus (n. gen., n. sp.) and the medium-sized T. parvus (n. sp.), were recorded in the Upper Miocene of the Chesapeake Group in the Eastover Formation (7.0–6.0 Ma) and St. Marys Formation (10.0-8.0 Ma). These two distinct subfamilies of seals indicate a well-marked divergence between phocines and monachines, much earlier than 18 million years ago, as previously suggested. The Eastover Formation was deposited in a shallow embayment that covered southern Maryland, the coastal plain of Virginia, and the northeastern corner of North Carolina. The geologically older St. Marys Formation represents a tide-influenced coastal environment, with low-salinity estuaries. There was a sharp temperature decrease in the Late Miocene, indicated by a shift to a cooler-water fish fauna during St. Marys time. The Eastover Formation reflects warmer waters with relatively strong currents, significant shoals, barriers, and varied depths. Fossil evidence of earlier seals suggests that phocids originated in the North Atlantic and otarioids in the North Pacific. True seals diverged from ancient Carnivora in the early Oligocene (or earlier) in the Paratethyan / Mediterranean Basins, spread widely during the Middle Miocene and crossed westward across the Atlantic Ocean, before dispersing in the eastern United States by the Early Pliocene.

scholarly journals Status and trends of terrestrial arthropod abundance and diversity in the North Atlantic region of the Arctic

AMBIO ◽  
2019 ◽  
Vol 49 (3) ◽  
pp. 718-731 ◽  
Author(s):  
Mark A. K. Gillespie ◽  
Matthias Alfredsson ◽  
Isabel C. Barrio ◽  
Joseph J. Bowden ◽  
Peter Convey ◽  
...  
Keyword(s):  
North Atlantic ◽  
The Arctic ◽  
North Atlantic Region ◽  
Atlantic Region ◽  
The North ◽  
Status And Trends ◽  
The North Atlantic ◽  
Abundance And Diversity ◽  
Arthropod Abundance

Parliamentarians Against Ministers: The Case of Western European Union

1960 ◽  
Vol 14 (1) ◽  
pp. 37-59 ◽  
Author(s):  
Ernst B. Haas ◽  
Peter H. Merkl
Keyword(s):  
European Union ◽  
Great Britain ◽  
North Atlantic ◽  
Social Role ◽  
Legal Basis ◽  
The North ◽  
Six Nations ◽  
The Family ◽  
The North Atlantic ◽  
Western European

Western European Union (WEU) is unique in the family of European organizations. Its membership comprises Great Britain in addition to the inner circle of the six nations of Little Europe. As such it was hailed as a big step forward from the continental limitations of European integration. Its special task, besides residuary powers in the cultural, social, and economic field, has been defense and the control of armaments. Western European Union was erected on the ruins of the European Defense Community (EDC) by the Paris Agreements of October 1954. Its legal basis was the Brussels Treaty Organization of 1948, a defensive alliance against future German aggression which over the years had left its military functions to the North Atlantic Treaty Organization (NATO) and had concentrated on its cultural and social role.

scholarly journals Distribution, abundance, and growth of anglerfish (Lophius piscatorius) on the Porcupine Bank (west of Ireland)

2008 ◽  
Vol 65 (7) ◽  
pp. 1316-1325 ◽  
Author(s):  
Francisco Velasco ◽  
Jorge Landa ◽  
Joaquín Barrado ◽  
Marian Blanco
Keyword(s):  
North Atlantic ◽  
Cohort Analysis ◽  
Age Groups ◽  
Age Classes ◽  
The North ◽  
Younger Age ◽  
First Results ◽  
The North Atlantic ◽  
Abundance And Distribution ◽  
West Of Ireland

Abstract Velasco, F., Landa, J., Barrado, J., and Blanco, M. 2008. Distribution, abundance, and growth of anglerfish (Lophius piscatorius) on the Porcupine Bank (west of Ireland). – ICES Journal of Marine Science, 65: 1316–1325. This manuscript presents the first results on abundance and distribution of white anglerfish (Lophius piscatorius) from a series of groundfish surveys carried out on the Porcupine Bank. White anglerfish were caught in all trawlable areas, recruits and juveniles mainly from the shallower parts of the bank, around the central mound and closer to the Irish shelf. A strong cohort was manifest in 2001, and it could be tracked over time by age matrices obtained with illicia age–length keys (ALKs) collected during the surveys. However, a mismatch in the cohort analysis suggests that the growth pattern based on illicia underestimates around three of the younger age classes. Using an ALK estimated numerically from a faster growth model, this mismatch disappears, which seems to confirm faster growth. Recruits of the 0-group and adults of age 4 (with the faster growth: ca. ∼57–65 cm) dominated, whereas the intermediate age groups were scarce on the bank. These results and recent findings from tag-and-recapture experiments suggest that white anglerfish move to and from the Porcupine Bank, calling into question the stock boundaries currently accepted for the species in the North Atlantic.

Revision of the family Ammodytidae (Perciformes) in the Mediterranean with the first record of Gymnammodytes semisquamatus

1990 ◽  
Vol 70 (3) ◽  
pp. 493-504 ◽  
Author(s):  
A. Sabatés ◽  
M. Demestre ◽  
P. Sanchez
Keyword(s):  
North Atlantic ◽  
First Record ◽  
Latitudinal Cline ◽  
Meristic Characters ◽  
The North ◽  
Meristic Counts ◽  
The Family ◽  
Nw Mediterranean ◽  
The North Atlantic ◽  
The Mediterranean

The study of the morphological and meristic characters of larval and adult sandeels (Gymnammodytes spp.) collected off the Catalan coast (NW Mediterranean) has revealed the co-occurrence of G. cicerelus and G. semisquamatus in the Mediterranean. The geo-graphical distribution of G. semisquamatus had hitherto been thought to be limited to the European Atlantic coasts. The comparative analysis of specimens of G. semisquamatus from the Mediterranean and from the North Atlantic has demonstrated a marked latitudinal cline in the meristic counts. An exhaustive overview is presented of the bibliography referring to the Ammodytidae family in the Mediterranean, and the validity of the numerous references is discussed. Finally, it has been shown that the accepted description of G. cicerelus included the two species: G. cicerelus and G. semisquamatus. In the present paper an up-to-date diagnosis of both species is presented.

scholarly journals On the peopling of the Americas: molecular evidence for the Paleoamerican and the Solutrean models

2017 ◽  
Author(s):  
Dejian Yuan ◽  
Shi Huang
Keyword(s):  
North Atlantic ◽  
North Atlantic Ocean ◽  
Molecular Evidence ◽  
Bering Strait ◽  
East Asians ◽  
The North ◽  
Pack Ice ◽  
Peopling Of The Americas ◽  
Close Relationship ◽  
The North Atlantic

AbstractMorphological and archaeological studies suggest that the Americas were first occupied by non-Mongoloids with Australo-Melanesian traits (the Paleoamerican model), which was subsequently followed by Southwest Europeans coming in along the pack ice of the North Atlantic Ocean (the Solutrean model) and by East Asians and Siberians arriving by way of the Bering Strait. Past DNA studies, however, have produced different accounts. With a better understanding of genetic diversity, we have now reinterpreted public DNA data. Consistent with our recent finding of a close relationship between South Pacific populations and Denisovans or Neanderthals who were archaic Africans with Eurasian admixtures, the ∼9500 year old Kennewick Man skeleton with Australo-Melanesian affinity from North America was about equally related to Europeans and Africans, least related to East Asians among present-day people, and most related to the ∼42000 year old Neanderthal Mezmaiskaya-2 from Adygea Russia among ancient Eurasian DNAs. The ∼12700 year old Anzick-1 of the Clovis culture was most related to the ∼18720 year old El Miron of the Magdalenian culture in Spain among ancient DNAs. Amerindian mtDNA haplotypes, unlike their Eurasian sister haplotypes, share informative SNPs with Australo-Melanesians, Africans, or Neanderthals. These results suggest a unifying account of informative findings on the settlement of the Americas.

scholarly journals Isohaline Salinity Budget of the North Atlantic Salinity Maximum

2015 ◽  
Vol 45 (3) ◽  
pp. 724-736 ◽  
Author(s):  
Frank Bryan ◽  
Scott Bachman
Keyword(s):  
North Atlantic ◽  
Water Mass ◽  
Mesoscale Eddies ◽  
Surface Fluxes ◽  
Small Scale ◽  
Mixing Processes ◽  
The North ◽  
The North Atlantic ◽  
Averaged Model

AbstractIn this study, the salinity budget of the North Atlantic subtropical salinity maximum region for control volumes bounded by isohaline surfaces is analyzed. The authors provide closed budgets based on output from a high-resolution numerical simulation and partial budgets based on analyses of observational climatologies of hydrography and surface fluxes. With this choice of control volume, advection is eliminated from the instantaneous volume-integrated salt budget, and time-mean advection is eliminated from the budget evaluated from time-averaged data. In this way, the role of irreversible mixing processes in the maintenance and variability of the salinity maximum are more readily revealed. By carrying out the analysis with both near-instantaneous and time-averaged model output, the role of mesoscale eddies in stirring and mixing for this water mass is determined. This study finds that the small-scale mixing acting on enhanced gradients generated by the mesoscale eddies is approximately equal to that acting on the large-scale gradients estimated from climatological-mean conditions. The isohaline salinity budget can be related to water mass transformation rates associated with surface forcing and mixing processes in a straightforward manner. The authors find that the surface net evaporation in the North Atlantic salinity maximum region accounts for a transformation of 7 Sverdrups (Sv; 1 Sv ≡ 106 m3 s−1) of water across the 37-psu isohaline outcrop into the salinity maximum in the simulation, whereas the estimate based on climatological observations is 9 to 10 Sv.

scholarly journals End of the century CO2 concentrations do not have a negative effect on vital rates of Calanus finmarchicus, an ecologically critical planktonic species in North Atlantic ecosystems

2016 ◽  
Vol 73 (3) ◽  
pp. 937-950 ◽  
Author(s):  
Jeffrey A. Runge ◽  
David M. Fields ◽  
Cameron R. S. Thompson ◽  
Steven D. Shema ◽  
Reidun M. Bjelland ◽  
...  
Keyword(s):  
North Atlantic ◽  
North Atlantic Ocean ◽  
Co2 Concentration ◽  
Calanus Finmarchicus ◽  
Vital Rates ◽  
Significant Treatment ◽  
The North ◽  
Pco2 Treatment ◽  
Negative Effect ◽  
Abundance And Distribution

Abstract The Subarctic copepod, Calanus finmarchicus, is an ecologically critical foundation species throughout the North Atlantic Ocean. Any change in the abundance and distribution of C. finmarchicus would have profound effects on North Atlantic pelagic ecosystems and the services that they support, particularly on the coastal shelves located at the southern margins of the species' range. We tested the hypothesis that the physiological rates and processes of C. finmarchicus, determining its vital rates, are unaffected by increases in CO2 concentration predicted to occur in the surface waters of the ocean during the next 100 years. We reared C. finmarchicus from eggs to adults at a control (580 µatm, the ambient concentration at the laboratory's seawater intake) and at predicted mid-range (1200 µatm) and high (1900 µatm) pCO2. There was no significant effect of pCO2 on development times, lipid accumulation, feeding rate, or metabolic rate. Small but significant treatment effects were found in body length and mass (in terms of dry, carbon and nitrogen mass), notably a somewhat larger body size at the mid-pCO2 treatment; that is, a putatively beneficial effect. Based on these results, and a review of other studies of Calanus, we conclude that the present parameterizations of vital rates in models of C. finmarchicus population dynamics, used to generate scenarios of abundance and distribution of this species under future conditions, do not require an “ocean acidification effect” adjustment. A review of research on planktonic copepods indicates that, with only a few exceptions, impacts of increased CO2 are small at the levels predicted to occur during the next century.

Description of a New Species of Oligobrachia (Pogonophora) from the North Atlantic, With a Survey of the Oligobrachiidae

1978 ◽  
Vol 58 (2) ◽  
pp. 357-365 ◽  
Author(s):  
Eve C. Southward
Keyword(s):  
New Species ◽  
Continental Slope ◽  
North Atlantic ◽  
Rare Species ◽  
Experimental Studies ◽  
Bay Of Biscay ◽  
The North ◽  
The Family ◽  
The North Atlantic ◽  
A New Species

Collections of bottom-living animals from the continental slope of the northern Bay of Biscay contain a new species of Oligobrachia; this increases the number of species of Oligobrachia known from the North Atlantic to five. Oligobrachiids are quite frequently found incubating embryos and five individuals of the new species carry embryos. Oligobrachia embryos have been studied morphologically already (Ivanov, 1957, 1975; Southward & Southward, 1963; Brattegard, 1966; Ivanov & Gureeva, 1976) and should prove useful material for experimental studies in future. Incubation is also known in the family Siboglinidae, but neither embryos nor larvae have been seen in any other pogonophoran families. The Biscay collections also contain additional specimens of Oligobrachia ivanovi and these have been useful in revising the description of this rather rare species.

scholarly journals A Lagrangian study of the contribution of the Canary coastal upwelling to the open North Atlantic nitrogen budget

2020 ◽  
Author(s):  
Derara Hailegeorgis ◽  
Zouhair Lachkar ◽  
Christoph Rieper ◽  
Nicolas Gruber
Keyword(s):  
North Atlantic ◽  
Inorganic Nitrogen ◽  
Mesoscale Eddies ◽  
Ocean Modeling ◽  
Regional Ocean Modeling System ◽  
The North ◽  
Dominant Feature ◽  
Canary Upwelling ◽  
The North Atlantic ◽  
Offshore Transport

Abstract. The Canary Current System (CanCS) is a major Eastern Boundary Upwelling System (EBUS), known for its high nearshore productivity and for sustaining large fisheries. Only a part of the inorganic nutrients that upwell along Northwest Africa are being used to fuel the high nearshore productivity. The remainder together with some of the newly formed organic nutrients are exported offshore into the adjacent oligotrophic subtropical gyre of the North Atlantic. Yet, the offshore reach of these nutrients and their importance for the biogeochemistry of the open North Atlantic is not yet fully quantified. Here, we determine the lateral transport of both organic and inorganic nitrogen from the Canary upwelling and investigate the timescales, reach, and structure of offshore transport using a Lagrangian modelling approach. To this end, we track all water parcels entering the coastal ocean and upwelling along the Northwest African coast between 14° N and 35° N, as simulated by an eddy-resolving configuration of the Regional Ocean Modeling System (ROMS). Our model analysis suggests that the vast majority of the upwelled waters originate from offshore and below the euphotic zone (70 m depth), and once upwelled remain in the top 100 m. The offshore transport is intense, yet it varies greatly along the coast. The central CanCS (21° N–28° N) transports the largest amount of water offshore, thanks to a larger upwelling volume and a faster offshore transport. In contrast, the southern CanCS (14° N–21° N) exports more nitrogen from the nearshore, primarily because of the higher nitrogen-content of its upwelling waters. Beyond 200 km, this nitrogen offshore transport declines rapidly because the shallow depth of most water parcels supports high organic matter formation and subsequent export of the organic nitrogen to depth. The horizontal pattern of offshore transport is characterized by latitudinally alternating offshore-onshore corridors indicating a strong contribution of mesoscale eddies and filaments to the mean transport. Around 1/3 of the total offshore transport of water occurs around major capes along the CanCS. The persistent filaments associated with these capes are responsible for an up to four-fold enhancement of the offshore transport of water and nitrogen in the first 400 km. Much of this water and nitrogen stems from upwelling at quite some distance from the capes, confirming the capes' role in collecting water from along the coast. North of Cape Blanc and within the first 500 km from the coast, water recirculation is a dominant feature of offshore transport. This process, likely associated with mesoscale eddies, tends to reduce the efficiency of offshore transport. This process is less important in the southern CanCS along the Mauritanian coast. The Canary upwelling is modelled to supply around 44 mmol N m−2 yr−1 and 7 mmol N m−2 yr−1 to the North Atlantic Tropical Gyral (NATR) and the North Atlantic Subtropical Gyral East (NASE) Longhurst provinces, respectively. In the NATR, this represents nearly half (45 ± 15 %) of the estimated total new production, while in the NASE, this fraction is small (3.5 ± 1.5 %). Our results highlight the importance of the CanCS upwelling as a key source of nutrient to the open North Atlantic and stress the need for improving the representation of EBUS in global coarse resolution models.

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