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Growth and age of blue antimora were studied in waters of the Flemish Cap (Northwest Atlantic). Bottom trawl catches were represented by specimens aged 2–43 years, with total length of 112–680 mm and body weight of 6–2830 g. Fish at the age of 14–26 years (62% of catches) prevailed. The growth rates of males and females were similar, but males had a slightly shorter life expectancy (the maximum age was 41 and 43 years, respectively) and less average age (19.9 and 22.6 years, respectively). The species growth is best described by a logistic function (coefficients: а = 61.9, b = 5.4, с = 0.1). Comparison with the data from other regions was made using the von Bertalanffy growth equation with the following parameters: L∞ = 142.9, k = 0.01, t0 = −2.9. Blue antimora from the Northwest Atlantic turned out to be the most slow growing compared to the specimens from other areas of the species range. [ABSTRACT FROM AUTHOR]

Abstract Over the course of the past decade, in response to United Nations General Assembly resolutions calling for the protection of vulnerable marine ecosystems (VMEs), the Northwest Atlantic Fisheries Organization has closed 14 areas around the high-seas portion of Grand Bank and Flemish Cap to protect deep-sea coral and sponge habitats from impacts by bottom-contact fishing gears. Structural and functional connectivity for those areas were not explicitly considered in the area-selection process. We applied a particle-tracking model in each of four seasons to produce dispersal trajectories at the surface and 100 m from start points within the closed areas. These were run in forecast and hindcast modes to identify dispersal kernels. Currents at the surface, 100 m, 1000 m and "on bottom" were examined under an independent model (NEMO) to infer structural connectivity among the areas at relevant depths not available in the particle-tracking model. Spawning times and planktonic larval duration of the dominant sponges, sea pens and gorgonian corals were then considered to evaluate the trajectories as bio-physical models, while species distribution models identified potential source populations from hindcast projections. Five of the 14 areas, including the three largest closures, showed particle retention, with three others showing retention within 10 km of their boundaries. The regional pattern of currents and their topographic forcing emerged as a strong structuring agent. A system of weakly-connected closed areas to protect sea pen VMEs on Flemish Cap was identified. The conducted approach illustrates the added value of assessing/modelling networking properties when designing MPAs. Highlights • Connectivity models greatly enhance understanding of protected area conservation. • Most tracking model scenarios predict larval export from the region. • Extreme topographic steering is a major influence on connectivity below 100 m. • Bio-physical models predict self-recruitment in or near 8 of 14 closed areas. • A weak network identified on Flemish Cap connects areas closed to protect sea pens. [ABSTRACT FROM AUTHOR]

Abstract: To address a need for science‐based advice on issues of resource exploration, two oceanographic moorings were placed on the abyssal slope of northwest Flemish Cap from July 2013 to July 2014. These yielded some of the first long‐term moored measurements of velocity, temperature, and salinity in the region. Hydrographic and lowered‐ADCP measurements made during mooring deployment and recovery reveal that the deep Labrador Current flows approximately along isobaths between water depths of 1,200 and 2,200 m. However, these snapshots differ significantly, with stronger currents observed during the deployment survey. The mooring data, obtained near the 1,500 m isobath, reveal a complex temporal variation of the current. The velocity spectrum is dominated by a peak at a period of approximately 21 days, with power increasing with depth in the water column and varying through the year. In other boundary‐current studies, variations in the several‐week band have been attributed to baroclinic topographic Rossby waves, but with just two widely spaced moorings, we cannot infer the wave number and test for such waves using the dispersion relationship. However, an indirect estimate of wave number can be made by examining the variation of spectral power with depth, and doing this yields results that are reasonably consistent with a linear theory of baroclinic topographic Rossby waves for water of constant stratification over a planar slope. This agreement is somewhat surprising, given the simplicity of the theory and the complexity of the domain, but it appears to offer a clear indication of the importance of baroclinic vorticity dynamics in this region. [ABSTRACT FROM AUTHOR]

Ageing using otolith microstructure is based on the assumption that growth increments are deposited daily. Individuals of the glacier lanternfish (Benthosema glaciale) were collected in the Flemish Cap (north-west Atlantic) during June- July 2010. A total of 44 individuals (ranging from 28 to 49 mm standard length; <2 years old) were selected to analyse otolith microstructure using light microscopy in order to assess the reliability of the use of microincrements to infer the true age of this species. Three distinct zones were distinguished: the larval zone, the postlarval zone and the postmetamorphic zone. The otolith core was, on average, 8 ± 0.7 μm. The mean microincrement number in the larval zone was 42 ± 7.5 within a radius of 0.095 ± 0.010 mm whereas in the postlarval zone it was 25 ± 3.0 within a segment of 0.104 ± 0.015 mm. SEM examinations in a subsample of otoliths showed that the resolution power of the light microscope was sufficient to study both the larval and the postlarval zones. Back-calculation from the time of capture suggests a hatching period from mid-June to mid-December with a peak in September. The spawning time and daily deposition of the microincrements in B. glaciale are discussed. Ageing using otolith microstructure is based on the assumption that growth increments are deposited daily. Here, we analysed the otolith microstructure of the glacier lanternfish (Bentosema glaciale) and we concluded that microincrement counting should not be directly used to infer the true age of Age-class 1 fish in the Flemish Cap. Alternative methods for ageing this species should be explored. [ABSTRACT FROM AUTHOR]

ABSTRACT The Labrador Current flows southward along the continental margin off eastern Canada and is the principal source of sediment to the outer continental margin areas where ice sheets did not cross the continental shelf. We present multi-proxy mineralogical and geochemical records based principally on X-ray diffraction and X-ray fluorescence for core 2011031-059 from northern Flemish Cap to determine changes in supply and hence to reconstruct provenance evolution during the last glacial cycle. The calcite to dolomite ratios in Heinrich layers ranged from 2 to 4, suggesting carbonate layers derived from Hudson Strait as early as Marine Isotope Stage (MIS) 5a-d. Mineral abundance shows three time-dependent predominant sediment sources other than in Heinrich layers: (i) Baffin Bay shelves and adjacent land in MIS 5 and 1, with high Ca, Sr, kaolinite and feldspars and low clay minerals and calcite/dolomite ratios; (ii) Labrador in MIS 3, with low clays and grey color; and (iii) north-east Newfoundland Shelf in MIS 2 and 4, with higher concentrations of clay minerals, red sandstones and transition elements. These results allow a reconstruction of principal ice streams supplying the north-west Atlantic over the last full glacial cycle. [ABSTRACT FROM AUTHOR]

Myctophids play a key role in the transfer of energy in pelagic food webs, linking zooplankton to higher trophic levels. Data are presented, for the first time for the glacier lanternfish ( Benthosema glaciale), on maturity ogives, size-at-maturity and reproductive strategy in terms of ovarian organization and fecundity type in two contrasting environments: North Atlantic and Mediterranean. We analysed 292 females collected in Flemish Cap during early summer 2009 and 2011 and off the Balearic Islands during late autumn 2009 and early summer 2010. The spawning season differed between areas. Size at 50% maturity in Flemish Cap was 47.6 and 49.1 mm in 2009 and 2011, respectively, but significantly smaller, 24.5 mm, in the Balearic sea. B. glaciale is a batch spawner with asynchronous ovarian development and indeterminate fecundity. Batch fecundity showed significant relationships with length and weight, although average relative batch fecundity was low (1031 ± 396 oocytes/gram). We compared two staining techniques: Hematoxylin-eosin and PAS-hematoxylin-metanil yellow with the latter being more useful to detect mature females and spawning indicators in regressing and regenerating females. Our results contribute to a better understanding of the reproductive potential and ecological role of this species, the most abundant myctophid in the northern Atlantic. [ABSTRACT FROM AUTHOR]

The feeding dynamics of the glacier lanternfish Benthosema glaciale were studied during the summer of 2010 in the Flemish Cap. B. glaciale constituted a majority of the deep scattering layer (DSL), which was located between 300 and 650 m during daylight hours; at night, a part of the DSL migrated to the surface. B. glaciale is a zooplanktivore, feeding primarily on copepods ( Calanus hyperboreus, Pareuchaeta norvegica, Metridia longa and Calanus finmarchicus), followed by amphipods ( Themisto compressa) and krill (primarily Nematoscelis spp.). Although crustaceans dominated the diet, other invertebrates, such as chaetognaths, gastropods, polychaetes, ostracods and appendicularians, also contributed. The geographical differences in the composition of the diet resulted from the association of prey with distinct water masses. In the colder water at the north of the bank, Arctic species represented a higher proportion of the diet, but this situation was reversed in areas influenced by the warmer water from the south. B. glaciale fed more intensively towards the centre of the Flemish Cap. The diet of B. glaciale shifted ontogenetically, showing increasing prey size and prey diversity with increasing predator size. [ABSTRACT FROM AUTHOR]

Pérez-Rodríguez, A., Koen-Alonso, M., and Saborido-Rey, F. 2012. Changes and trends in the demersal fish community of the Flemish Cap, Northwest Atlantic, in the period 1988–2008. – ICES Journal of Marine Science, 69: 902–912.The Flemish Cap fish community (NAFO Division 3M) has been fished since the 1950s, and major changes in the biomass and abundance of its most important commercial species have been reported since the late 1980s. Variations in oceanographic conditions at the Cap, with alternating periods of cold and warm weather, have also been described. This work examines the existence of common trends in the biomass levels of the main demersal species over time using dynamic factor analysis, and the occurrence of “occasional species” was explored in relation to temperature conditions. Overall, there have been significant changes in community structure involving both commercial and non-commercial species. Common trends among species were identified and overall fishing pressure, environmental conditions (represented by a moving average of the North Atlantic Oscillation, NAO), and predation pressure (represented by the abundance of piscivorous fish) emerged as important drivers of the temporal dynamics. The NAO influence in the dynamics of most species was in agreement with their temperature preference. For occasional species, their pattern of occurrence appears also to be linked to changes in temperature regimes. [ABSTRACT FROM PUBLISHER]

In this study, we report the sequencing of the whole genome [including the 5′ and 3′ non-coding regions (NCR) of both segments A and B] of seven birnavirus strains isolated from wild fish from the Flemish Cap (FC) fishery at Newfoundland, Canada. From analysis and comparison of the sequences, most of the FC isolates clustered with the North American reference strains West Buxton (WB), Dry Mill and Jasper. One strain was included in the same genotype as the European strain Ab. In addition, at least in one case cohabitation of both type strains in an individual fish was demonstrated. These results clearly suggest the acquisition of the viruses from two different sources. The prevalence of the American type is easily explained by the close proximity of this fishing bank to the American coast whereas, although surprising, the presence of the European type strain could be because of migration of fish from European waters. In one strain, segment A and B sequences were typed differently (WB and Ab, respectively). These findings indicate natural reassortment between two strains of aquabirnaviruses in a host. [ABSTRACT FROM AUTHOR]

This study tests the stability of environmental preferences and willingness to pay (WTP) values using a discrete choice experiment (DCE) across three countries pre and post the peak of the first wave of the Covid-19 pandemic. A DCE examining the public's preferences for alternative environmental management plans on the high seas, in the area of the Flemish Cap, was carried out in Canada, Scotland and Norway in late 2019 and was rerun in early May 2020 shortly after the Covid-19 pandemic had officially peaked in the three countries. The same choice set sequence is tested across the two periods, using different but nationally representative samples in each case. Entropy balancing, a multivariate reweighting method, is used to achieve covariate balance between the pre and post Covid samples in the analysis. The results suggest that both preferences and WTP remain relatively stable in the face of a major public health crisis and economic upheaval. [ABSTRACT FROM AUTHOR]

Over the past 30 years, a widely accepted model of "open-access" fisheries has been developed, yet empirical tests of the standard model have been relatively few. One difficulty is that fish stocks, the levels of which affect the rate of catch, are not directly observable. Simplifying assumptions are generally required, such as the assumption that catchability does not change over time. Estimation on the basis of the standard model also raises difficulties in specification, if contemporaneous correlation of the error term with one of the regressors is to be avoided. This paper describes an algorithm that imposes a less restrictive pattern (than constancy) on catchability, yet does so in an econometrically acceptable fashion. It also reports on an application of this algorithm to the Flemish Cap groundfishery over the period from 1971 to 1985. [ABSTRACT FROM AUTHOR]

A histological method is used to detect the proportion of both adult and recruit females at the beginning of gonad development, in summer, a few months after spawning. At this time it is difficult to make a visual diagnosis of the sexual maturity stage. The proportion of females with postovulatory follicles is used to determine the length and age at maturity in the year of sampling, and the proportion of females in the cortical alveoli and/or vitellogenic stages is used to estimate the same parameter for the following year. Variations in age and length at maturity during the period 1992–1995 were analysed by comparing the respective maturity curves of both the “previous spawners” and the “next-year spawners” females. A drastic decrease in both the age and the length at maturity is observed in this period and it seems likely that the age at maturity of female cod became fixed at around age 3 at the end of the period analysed. The possibility that this could be a density-dependent response of the stock at the Flemish Cap is discussed. [ABSTRACT FROM PUBLISHER]

The food and feeding of Flemish Cap cod are described for 5 years based on 3921 stomachs collected in the fishing grounds off the Flemish Cap, Newfoundland in summer 1989–1993. Feeding intensity was high but the prey spectrum was narrow in all years with hyperiids and redfish (Sebastes sp.) predominating. Squid and poly-chaetes had a high inter-annual variability. Juvenile cod diet was dominated by crustaceans, mainly hyperiids, and polychaetes, while in adult cod diet the most important prey were fish, mainly redfish. The maximum size of redfish eaten increased with cod size, but prey–predator size relationships showed weak correlation. Cannibalism increased in 1991 (mainly upon 1-year-olds), coinciding with the appearance of a large year class in 1990. In the years 1992 and 1993, a change in the diet was observed involving an increase of hyperiids in the adult cod diet and a decline of redfish. [ABSTRACT FROM PUBLISHER]

The Orphan Basin and Flemish Pass region on the Newfoundland continental margin is a frontier area in terms of oil and gas exploration and remains poorly understood in terms of structural evolution and rift development. The area has few exploration wells and, until recently, sparse seismic data coverage. Existing gravity inversion and seismic refraction data from the area suggest that stretched continental crust in the Orphan Basin is highly attenuated (locally to < 5 km) but previously published structural restorations have been unable to fully restore the continental crust below the Orphan Basin to pre-deformed thicknesses (30–32 km). Here we perform a structural restoration of a regional, WNW-ESE oriented cross-section to investigate crustal structure, rifting style, and structural evolution of the Orphan Basin and Flemish Pass region. Interpretation is constrained by modern regional depth converted broadband 2D and 3D seismic reflection data, well data, and published gravity inversion results. Present-day crustal thicknesses are used as constraints for crustal area balancing and estimation of crustal thinning across the basin. We find that low-angle extensional detachments are widespread in the area, with offsets on individual structures of up to 42 km. Zones of attenuated continental crust are coincident with the presence of low-angle detachment surfaces displaying isostatic uplift of detachment footwalls. Comparison of total extension derived from crustal area balancing vs. structural restoration suggests approximately 39% of extension across the cross-section is unresolvable in seismic data. We attribute this to (i) ductile deformation prior to brittle faulting, (ii) subseismic-scale faulting, (iii) uncertainties in detachment breakaway positions, and (iv) unresolvable later offset of detachment surfaces. Widespread and relatively evenly distributed extension across the Orphan Basin and Flemish Pass region from Middle-Late Jurassic to Early Cretaceous influences sediment distribution across the region. Calibrated regional seismic mapping of the Orphan Basin suggests that significant thicknesses of Jurassic strata exist throughout the area, including in the northwestern part of the study area, where Kimmeridgian and Tithonian strata reach combined thicknesses of up to 4.9 km. • sSignificantthicknesses of Jurassic strataidentified throughout the Orphan Basin and Flemish Pass. • kinematic restoration and crustal area balancing used to constrain timing and amount of extension across the study area. • Structure dominated by low-angle extensional detachments with offsets on individual structures of up to 42 km. • Attenuated continental crust is coincident with low-angle detachment surfaces and isostatic uplift of detachment footwalls. [ABSTRACT FROM AUTHOR]

• The structure-forming sponges and small gorgonian corals enhance biodiversity. • Chronic impact from fishing activities have negatively impacted benthic diversity. • Over 60% of the estimated number of benthic species of the Flemish Cap is under protection. • Biodiversity from shallow waters remains unprotected. The ecological diversity of benthic invertebrates from bottom trawl surveys was mapped for the Flemish Cap, a plateau of ~200 km radius in the northwest Atlantic. Species density (SpD), the exponential Shannon diversity index (e H′) and Heip's index of evenness (E ~ ') were measured at different spatial scales. Continuous surfaces of each were created to 2000 m depth using predictive distribution models based on random forest (RF) algorithms. When fishing effort was included as an independent variable in the RF models, it was the most important predictor of sample SpD but unimportant in predicting e H′ and only a minor predictor of E ~ '. In the absence of a historical baseline, we used a novel approach to evaluate spatial impacts of fishing on diversity by simulating and comparing spatial SpD prediction surfaces using response data associated with different levels of fishing effort. Although it is not possible to fully evaluate the precise nature of the impact of fishing on the ecological diversity, our models have identified Sackville Spur, Flemish Pass and south of Flemish Cap as the areas of greatest impact. Combining minimum bottom salinity, annual primary production range, fishing effort and biomass of sponges and small gorgonian corals, resulted in the best performing generalized additive model, explaining 73% of the total variance in SpD. Although current closures to protect vulnerable marine ecosystems from the adverse impacts of bottom fishing activities protect an important part of the ecological diversity associated with the deeper communities, unique and representative habitats on top of the Cap remain unprotected. [ABSTRACT FROM AUTHOR]