In situ evidence of the role of Crangon crangon in infection of cod Gadus morhua with nematode parasite Hysterothylacium aduncum in the Baltic Sea

AbstractCod (Gadus morhua), an important fish species in the Baltic Sea, is the paratenic host for many parasite species, including the zoonotic nematodes, Anisakis sp. and Contracaecum osculatum. We aimed to identify which invertebrate species (found in situ in the fish stomach) are responsible for infection of cod with zoonotic nematodes. We found that Crangon crangon and Gammarus sp., both invertebrate prey species of cod, were infected with Anisakis simplex and C. osculatum, respectively. These host–parasite systems are reported here for the first time, implicating C. crangon and Gammarus sp. as sources of infection of Baltic cod with zoonotic nematodes.

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Multidecadal Sea Level Variability in the Baltic Sea and Its Impact on Acceleration Estimations

Frontiers in Marine Science ◽

10.3389/fmars.2021.702512 ◽

2021 ◽

Vol 8 ◽

Author(s):

Armin Agha Karimi ◽

Mohammad Bagherbandi ◽

Milan Horemuz

Keyword(s):

Baltic Sea ◽

Sea Level Rise ◽

Sea Level ◽

Tide Gauge ◽

Linear Trend ◽

The Baltic Sea ◽

Warming Hiatus ◽

The Baltic

Multidecadal sea level variation in the Baltic Sea is investigated from 1900 to 2020 deploying satellite and in situ datasets. As a part of this investigation, nearly 30 years of satellite altimetry data are used to compare with tide gauge data in terms of linear trend. This, in turn, leads to validation of the regional uplift model developed for the Fennoscandia. The role of North Atlantic Oscillation (NAO) in multidecadal variations of the Baltic Sea is also analyzed. Although NAO impacts the Baltic Sea level on seasonal to decadal time scales according to previous studies, it is not a pronounced factor in the multidecadal variations. The acceleration in the sea level rise of the basin is reported as statistically insignificant in recent studies or even decelerating in an investigation of the early 1990s. It is shown that the reason for these results relates to the global warming hiatus in the 1950s−1970s, which can be seen in all eight tide gauges used for this study. To account for the slowdown period, the acceleration in the basin is investigated by fitting linear trends to time spans of six to seven decades, which include the hiatus. These results imply that the sea level rise is accelerated in the Baltic Sea during the period 1900–2020.

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Saduria entomon infected with Hysterothylacium aduncum found in situ in the stomach of cod (Gadus morhua) from the Baltic Sea

Journal of Helminthology ◽

10.1017/s0022149x1700092x ◽

2017 ◽

Vol 92 (5) ◽

pp. 645-648 ◽

Cited By ~ 3

Author(s):

J. Pawlak ◽

K. Nadolna-Ałtyn ◽

B. Szostakowska ◽

M. Pachur ◽

M. Podolska

Keyword(s):

Baltic Sea ◽

Life Cycles ◽

The Baltic Sea ◽

Source Of Infection ◽

General Terms ◽

The Baltic ◽

Hysterothylacium Aduncum ◽

Saduria Entomon ◽

Baltic Cod

AbstractThe parasite fauna of cod (Gadus morhus) is well described, but the life cycles of Baltic cod parasites are known only in general terms. Invertebrates commonly found in the stomach of cod are recognized as intermediate hosts in the life cycles of nematodes or acanthocephalans. The aim of this study was to determine the source of infection of Baltic cod with parasites found in situ in invertebrates present in the cod stomach. Our results indicate that Saduria entomon is both a source of infection of Baltic cod with parasites and an intermediate host in the life cycle of Hysterothylacium aduncum in the Baltic Sea.

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In-Situ Evaluation of the Protectivity of Coatings Applied to Metal Cultural Artefacts Using Non-Destructive Electrochemical Measurements

Corrosion and Materials Degradation ◽

10.3390/cmd2010007 ◽

2021 ◽

Vol 2 (1) ◽

pp. 120-132

Author(s):

Douglas J. Mills ◽

Katarzyna Schaefer ◽

Tomasz Wityk

Keyword(s):

Baltic Sea ◽

Electrochemical Noise ◽

Organic Coating ◽

Noise Measurement ◽

The Baltic Sea ◽

Coating Type ◽

The Baltic ◽

Non Destructive ◽

Electrolytic Resistance

Electrochemical Noise Measurement (ENM) and DC electrolytic resistance measurement (ERM) can be used to assess the level of protectiveness provided by an organic coating (paint or varnish) to the underlying metal. These techniques also have applicability to the thinner, transparent type of coatings used to protect archaeological artefacts. Two studies are presented here demonstrating how ERM and ENM techniques can be applied in artefact preservation. The similarity of the techniques, both of which are a measure of resistance, means results can be considered to be analogous. The first study investigated the use of ERM to determine the protection levels provided by typical coatings in order to develop a database of coating type and application for objects, for specific environments. The second study used ENM to evaluate coatings which had been applied to historic artefacts recovered from shipwrecks in the Baltic Sea and displayed inside the museum or kept in the museum store area. The studies showed the usefulness of both techniques for determining the level of protection of a coating and how a better performing coating can be specified if a pre-existing coating on an artefact has been found to be unsuitable.

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Deoxygenation impacts on Baltic Sea cod: Dramatic declines in ecosystem services of an iconic keystone predator

AMBIO ◽

10.1007/s13280-021-01572-4 ◽

2021 ◽

Author(s):

Alessandro Orio ◽

Yvette Heimbrand ◽

Karin Limburg

Keyword(s):

Ecosystem Services ◽

Baltic Sea ◽

Gadus Morhua ◽

Generalized Additive Model ◽

Additive Model ◽

Maximum Length ◽

The Baltic Sea ◽

Hypoxic Zone ◽

The Baltic ◽

Baltic Cod

AbstractThe intensified expansion of the Baltic Sea’s hypoxic zone has been proposed as one reason for the current poor status of cod (Gadus morhua) in the Baltic Sea, with repercussions throughout the food web and on ecosystem services. We examined the links between increased hypoxic areas and the decline in maximum length of Baltic cod, a demographic proxy for services generation. We analysed the effect of different predictors on maximum length of Baltic cod during 1978–2014 using a generalized additive model. The extent of minimally suitable areas for cod (oxygen concentration ≥ 1 ml l−1) is the most important predictor of decreased cod maximum length. We also show, with simulations, the potential for Baltic cod to increase its maximum length if hypoxic areal extent is reduced to levels comparable to the beginning of the 1990s. We discuss our findings in relation to ecosystem services affected by the decrease of cod maximum length.

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An ecosystem model of food web and fisheries interactions in the Baltic Sea

ICES Journal of Marine Science ◽

10.1016/s1054-3139(03)00098-5 ◽

2003 ◽

Vol 60 (5) ◽

pp. 939-950 ◽

Cited By ~ 89

Author(s):

Chris J Harvey ◽

Sean P Cox ◽

Timothy E Essington ◽

Sture Hansson ◽

James F Kitchell

Keyword(s):

Baltic Sea ◽

Food Web ◽

Species Interactions ◽

Gadus Morhua ◽

Population Analysis ◽

Clupea Harengus ◽

Trophic Relationships ◽

The Baltic Sea ◽

Management Actions ◽

The Baltic

Abstract Because fisheries operate within a complex array of species interactions, scientists increasingly recommend multispecies approaches to fisheries management. We created a food web model for the Baltic Sea proper, using the Ecopath with Ecosim software, to evaluate interactions between fisheries and the food web from 1974 to 2000. The model was based largely on values generated by multispecies virtual population analysis (MSVPA). Ecosim outputs closely reproduced MSVPA biomass estimates and catch data for sprat (Sprattus sprattus), herring (Clupea harengus), and cod (Gadus morhua), but only after making adjustments to cod recruitment, to vulnerability to predation of specific species, and to foraging times. Among the necessary adjustments were divergent trophic relationships between cod and clupeids: cod exhibited top-down control on sprat biomass, but had little influence on herring. Fishing, the chief source of mortality for cod and herring, and cod reproduction, as driven by oceanographic conditions as well as unexplained variability, were also key structuring forces. The model generated many hypotheses about relationships between key biota in the Baltic Sea food web and may ultimately provide a basis for estimating community responses to management actions.

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Marika Mägi: In Austrvegr. The Role of the Eastern Baltic in Viking Age Communication across the Baltic Sea (The Northern World, vol. 84). Brill. Leiden and Boston 2018. 512 p. ISBN 9789004216655.

Forschungen zur baltischen Geschichte ◽

10.30965/9783657760237_017 ◽

2020 ◽

pp. 255-259

Keyword(s):

Baltic Sea ◽

Viking Age ◽

The Baltic Sea ◽

The Baltic ◽

Eastern Baltic

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Evaluation of Sentinel-3A OLCI Products Derived Using the Case-2 Regional CoastColour Processor over the Baltic Sea

Sensors ◽

10.3390/s19163609 ◽

2019 ◽

Vol 19 (16) ◽

pp. 3609 ◽

Cited By ~ 11

Author(s):

Kyryliuk ◽

Kratzer

Keyword(s):

Remote Sensing ◽

Baltic Sea ◽

Attenuation Coefficient ◽

Secchi Depth ◽

Local Algorithm ◽

The Baltic Sea ◽

In Situ Data ◽

The Baltic ◽

Level 2

In this study, the Level-2 products of the Ocean and Land Colour Instrument (OLCI) data on Sentinel-3A are derived using the Case-2 Regional CoastColour (C2RCC) processor for the SentiNel Application Platform (SNAP) whilst adjusting the specific scatter of Total Suspended Matter (TSM) for the Baltic Sea in order to improve TSM retrieval. The remote sensing product “kd_z90max” (i.e., the depth of the water column from which 90% of the water-leaving irradiance are derived) from C2RCC-SNAP showed a good correlation with in situ Secchi depth (SD). Additionally, a regional in-water algorithm was applied to derive SD from the attenuation coefficient Kd(489) using a local algorithm. Furthermore, a regional in-water relationship between particle scatter and bench turbidity was applied to generate turbidity from the remote sensing product “iop_bpart” (i.e., the scattering coefficient of marine particles at 443 nm). The spectral shape of the remote sensing reflectance (Rrs) data extracted from match-up stations was evaluated against reflectance data measured in situ by a tethered Attenuation Coefficient Sensor (TACCS) radiometer. The L2 products were evaluated against in situ data from several dedicated validation campaigns (2016–2018) in the NW Baltic proper. All derived L2 in-water products were statistically compared to in situ data and the results were also compared to results for MERIS validation from the literature and the current S3 Level-2 Water (L2W) standard processor from EUMETSAT. The Chl-a product showed a substantial improvement (MNB 21%, RMSE 88%, APD 96%, n = 27) compared to concentrations derived from the Medium Resolution Imaging Spectrometer (MERIS), with a strong underestimation of higher values. TSM performed within an error comparable to MERIS data with a mean normalized bias (MNB) 25%, root-mean square error (RMSE) 73%, average absolute percentage difference (APD) 63% n = 23). Coloured Dissolved Organic Matter (CDOM) absorption retrieval has also improved substantially when using the product “iop_adg” (i.e., the sum of organic detritus and Gelbstoff absorption at 443 nm) as a proxy (MNB 8%, RMSE 56%, APD 54%, n = 18). The local SD (MNB 6%, RMSE 62%, APD 60%, n = 35) and turbidity (MNB 3%, RMSE 35%, APD 34%, n = 29) algorithms showed very good agreement with in situ data. We recommend the use of the SNAP C2RCC with regionally adjusted TSM-specific scatter for water product retrieval as well as the regional turbidity algorithm for Baltic Sea monitoring. Besides documenting the evaluation of the C2RCC processor, this paper may also act as a handbook on the validation of Ocean Colour data.

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