First records of the Oak bush-cricket Meconema thalassinum on three German North Sea islands (Orthoptera: Ensifera, Tettigoniidae)

Global ocean warming results in an increase of infectious diseases including an elevated emergence of Vibrio spp. in Northern Europe. The European Centre for Disease Prevention and Control reported annual periods of high to very high risks of infection with Vibrio spp. during summer months along the North Sea and Baltic Sea coasts. Based on those facts, the risk of Vibrio infections associated with recreational bathing in European coastal waters increases. To obtain an overview of the seasonal and spatial distribution of potentially human pathogenic Vibrio spp. at German coasts, this study monitored V. cholerae, V. parahaemolyticus, and V. vulnificus at seven recreational bathing areas from 2017 to 2018, including the heat wave event in summer 2018. The study shows that all three Vibrio species occurred in water and sediment samples at all sampling sites. Temperature was shown to be the main driving factor of Vibrio abundance, whereas Vibrio community composition was mainly modulated by salinity. A species-specific rapid increase was observed at water temperatures above 10°C, reaching the highest detection numbers during the heat wave event with abundances of 4.5 log10 CFU+1/100 ml of seawater and 6.5 log10 CFU+1/100 g of sediment. Due to salinity, the dominant Vibrio species found in North Sea samples was V. parahaemolyticus, whereas V. vulnificus was predominantly detected in Baltic Sea samples. Most detections of V. cholerae were associated with estuarine samples from both seas. Vibrio spp. concentrations in sediments were up to three log higher compared to water samples, indicating that sediments are an important habitat for Vibrio spp. to persist in the environment. Antibiotic resistances were found against beta-lactam antibiotics (ampicillin 31%, cefazolin 36%, and oxacillin and penicillin 100%) and trimethoprim-sulfamethoxazole (45%). Moreover, isolates harboring pathogenicity-associated genes such as trh for V. parahaemolyticus as well as vcg, cap/wcv, and the 16S rRNA-type B variant for V. vulnificus were detected. All sampled V. cholerae isolates were identified as non-toxigenic non-O1/non-O139 serotypes. To sum up, increasing water temperatures at German North Sea and Baltic Sea coasts provoke elevated Vibrio numbers and encourage human recreational water activities, resulting in increased exposure rates. Owing to a moderate Baltic Sea salinity, the risk of V. vulnificus infections is of particular concern.

ABSTRACTTo resolve historical misinterpretations of species descriptions and to comprehend the morphological diversity together with the distribution of Ulva compressa Linnaeus in northern Germany, a morphological and molecular study was undertaken of recently collected specimens and herbarium vouchers. Phylogenetic analyses from sequences of the plastid encoded tufA gene confirmed that U. compressa is abundant along the German Baltic Sea and North Sea coasts. We were able to genetically confirm the presence of U. compressa in the Baltic Sea below salinities of 15 PSU. However, we detected morphologies agreeing with the attached and branched tubular type material only in the North Sea, while U. compressa on Baltic Sea coasts indiscriminately exhibited a very distinct morphology of sheet-like thalli that were always unattached, with the exception of one collection site. Drifting forms were also frequently detected in the Wadden Sea, but not on the island of Helgoland. The tufA sequences of attached and tubular forms of U. compressa from the German Wadden Sea were identical to the drifting sheets found in the Wadden and Baltic Seas and the sequence divergence was extremely small at ≤0.9%. The proliferating, blade-like thalli of U. compressa appear as a nuisance ecotype that is able to form massive accumulations associated with oxygen depletion. Mass accumulations were observed to cause severe damage and increased mortality of habitat forming Zostera and Ruppia populations.

Governments are under increasing pressure to reduce greenhouse gas emissions, and large-scale wind farms are being developed in marine environments worldwide. However, top predators are strongly affected by environmental change and anthropogenic activities. Common guillemots (Uria aalge, hereafter guillemots), as one of the world’s most numerous seabird species, are prone to interference with offshore wind farms (OWFs). This study assessed the cumulative impacts of all operating OWFs on guillemots in the German North Sea. These estimates were applied to quantify the possible conflicts between guillemot occurrence and current German government plans to implement large-scale OWFs. If OWFs were implemented according to the current maritime spatial plan for the German Exclusive Economic zone, they would cover 13% of the German North Sea. Guillemot numbers peak during autumn, with German North Sea offshore waters hosting approximately 90,000 individuals. Guillemot density in autumn was significantly reduced within a radius of 19.5 km around operating OWFs. Applying this disturbance distance to current installation plans, about 70% of the German North Sea would be affected, and an estimated 68% of guillemots in the German North Sea would experience habitat loss. This highlights the possible threat to guillemots in the southern North Sea if the current German government plans are implemented. The current estimates are highly relevant to decisions regarding marine spatial planning and management recommendations. Such evaluations are essential for developing sustainable scenarios including reducing the human CO2 footprint, whilst also conserving biodiversity.

Carbon dioxide storage in the deep subsurface of the North Sea is technically feasible and has been practiced for decades beneath Norwegian waters. Under the German North Sea, there are rock formations in which large quantities of carbon dioxide could presumably be stored, too. However, important questions remain, which are to be addressed and answered in the CDRmare research mission – with the aim of enabling a demonstration project for carbon dioxide storage in the geological subsurface of the German North Sea.

Factsheet: Carbon dioxide storage in the deep subsurface of the North Sea is technically feasible and has been practiced for decades beneath Norwegian waters. Under the German North Sea, there are rock formations in which large quantities of carbon dioxide could presumably be stored, too. However, important questions remain, which are to be addressed and answered in the CDRmare research mission – with the aim of enabling a demonstration project for carbon dioxide storage in the geological subsurface of the German North Sea.

Factsheet: Carbon dioxide storage in the deep subsurface of the North Sea is technically feasible and has been practiced for decades beneath Norwegian waters. Under the German North Sea, there are rock formations in which large quantities of carbon dioxide could presumably be stored, too. However, important questions remain, which are to be addressed and answered in the CDRmare research mission – with the aim of enabling a demonstration project for carbon dioxide storage in the geological subsurface of the German North Sea.

Background The German legislation sets two targets for riverine nitrogen concentrations in North Sea and Baltic Sea tributaries as well as river type-specific phosphorus thresholds. The current target for the Baltic Sea as well as the thresholds for the good status were derived from modeled riverine and atmospheric inputs around 1880. However, the calculated nitrogen balance differed between the model applications for the German North Sea and Baltic Sea. Existing nitrogen targets for North Sea tributaries are likely insufficient for environmental objectives according to recent model and data analyses. We used a harmonized approach to model nutrient inputs to the German Seas around 1880 and discuss these outcomes in the context of stricter requirements needed for ecological objectives in the North Sea. Results For river basins entering the German North Sea and Baltic Sea, we modeled emissions, concentrations, and loads of total nitrogen and total phosphorus around 1880. The historical riverine inputs to the North Sea were 180 kt N yr−1 and 4.20 kt P yr−1 and to the Baltic Sea 22 kt N yr−1 and 0.45 kt P yr−1, respectively. These loads corresponded to annual mean concentrations of 1.36 mg N l−1 and 0.032 mg P l−1 (North Sea) as well as 1.11 mg N l−1 and 0.022 mg P l−1 (Baltic Sea). Modeled nitrogen concentrations at river mouths were lower than the previous German model results but exceeded published reference concentrations. They were, however, partly in agreement with ecology-based concentrations for major North Sea tributaries based on published reduction needs. Conclusions The modeled nutrient concentrations at river mouths confirm the inconsistency of German model applications with regional applications. For the North Sea, they support a more stringent basin-wide nitrogen target and thresholds for the good status of coastal and marine waters. As the historical conditions exceeded reference conditions, the offset of 50% to the historical concentration for the good ecological status should be revised for both sea basins. According to ecology-based target concentrations, only + 30% may be acceptable for North Sea tributaries, corresponding to 1.8 mg N l−1. Any revision of the German legislation should acknowledge the inherent uncertainties.

The pathological, microbiological and serological findings in harbour porpoises hunted in Greenlandic waters were compared with the findings in animals accidentally caught in fishing gear in the German North Sea...

Immunohistological and serological investigation of morbillivirus infection in harbour porpoises ( Phocoena phocoena) from the German Baltic and North Sea

The North Sea is one of the most heavily used shelf regions worldwide with a diversity of human impacts, including shipping, pollution, fisheries, and offshore constructions. These stressors on the environment can have consequences for marine organisms, such as our study species, the harbor porpoise (Phocoena phocoena), which is regarded as a sentinel species and hence has a high conservation priority in the European Union (EU). As EU member states are obliged to monitor the population status, the present study aims to estimate trends in absolute harbor porpoise abundance in the German North Sea based on almost two decades of aerial surveys (2002–2019) using line-transect methodology. Furthermore, we were interested in trends in three Natura2000 Special Areas of Conservation (SACs), which include the harbor porpoise as designated feature. Trends were estimated for each SAC and two seasons (spring and summer) as well as the complete area of the German North Sea. For the trend analysis we applied a Bayesian framework to a series of replicated visual surveys, allowing to propagate the error structure of the original abundance estimates to the final trend estimate and designed to deal with spatio-temporal heterogeneity and other sources of uncertainty. In general, harbor porpoise abundance decreased in northern areas and increased in the south, such as in the SAC Borkum Reef Ground. A particularly strong decline with a high probability (94.9%) was detected in the core area and main reproduction site in summer, the SAC Sylt Outer Reef (−3.79% per year). The overall trend for the German North Sea revealed a decrease in harbor porpoise abundance over the whole study period (−1.79% per year) with high probability (95.1%). The assessment of these trends in abundance based on systematic monitoring should now form the basis for adaptive management, especially in the SAC Sylt Outer Reef, where the underlying causes and drivers for the large decline remain unknown and deserve further investigation, also in a regional North Sea wide context.

ABSTRACTSeismic data from the North Sea commonly show vertical acoustic blanking (VAB) often interpreted as fluid conduits with implications for Quaternary development. The robustness of this interpretation has long been controversial as the infill of tunnel valleys can also cause vertical blanking. Using 2D and 3D seismic data and sediment echosounder data from the German North Sea, we investigate VAB to determine a geological or imaging origin of these anomalies. We detected multiple VAB occurrences throughout the North Sea. 3D data from the Ducks Beak (‘Entenschnabel’) reveal a correlation of VAB with bright spots in incised channels directly below the seafloor. Large source–receiver distances allow imaging the subsurface below the channel without signal penetrating through it (undershooting). This method removes the blanking. Energy absorption by shallow biogenic gas trapped within the channels explains the observed VAB. Hence, the blanking represents an imaging artifact, highlighting the need for careful seismic processing with sufficient offset before interpreting such anomalies as fluid pathways. The channels belong to a postglacial channel system related to the now submerged lowlands of Doggerland. This work demonstrates the usability of mapping VAB to detect shallow features for paleo‐landscape reconstruction and identification of shallow gas for hazard assessments, for example.

Shallow gas accumulations in the German North Sea

Carbon dioxide storage in the deep subsurface of the North Sea is technically feasible and has been practiced for decades beneath Norwegian waters. Under the German North Sea, there are rock formations in which large quantities of carbon dioxide could presumably be stored, too. However, important questions remain, which are to be addressed and answered in the CDRmare research mission – with the aim of enabling a demonstration project for carbon dioxide storage in the geological subsurface of the German North Sea.

Coastal and offshore areas are highly relevant in the context of globalized economies and their demands for fisheries, transport and sustainable energy production. However, the ecological impacts of increasing human activity, such as noise disturbance and sediment dispersal from construction works and shipping traffic, could pose a threat to the biodiversity of marine ecosystems. By balancing marine food webs, controlling pests and dispersing seeds, marine birds are not only important for the conservation of biodiversity, but are also often seen as an early warning indicators of environmental change, as behavioural and physiological characteristics of bird populations are linked to changes in habitat quality. Spatial obervations of the distribution and size of bird populations are therefore needed to conserve biodiversity. Due to the vast extents and sometimes inaccessible nature of coastal and offshore areas, repeated airborne remote sensing surveys provide an efficient means of monitoring marine birds. However, the detection and classification of features on the ocean surface, such as animals, waves or man-made structures, remains challenging and is often achieved through time-consuming manual image inspection and annotation by trained experts.Here, we present first results of an AI-based approach to automatically detect and identify different features and facilitate the monitoring of marine bird species and populations: Our study is based on approximately 2.5 million optical images with a ground resolution of 2 cm from 60 airborne surveys which were conducted by the German Federal Agency for Nature Conservation (BfN) along the German North Sea and Baltic Sea coasts between 2017 and 2021. Previously, images with bird sightings from some surveys have been annotated manually, enabling the training of a deep learning algorithm. Technical challenges for AI-based bird detection include a wide range of image exposure conditions, from low to high brightness contrast between objects and background, insufficient spatial resolution for relatively small species and tracking specific birds that appear in successive overlapping images to avoid double counting. Thus, our method uses a neural network approach (Faster R-CNN) to localise potential object candidates (e.g. bird) within an entire image, while a subsequent network classifier identifies the broad classification category of the detected object. In addition, spatio-temporal tracking of the detected features is included by estimating the most likely object displacement within successive images based on flight speed and camera motion along each survey transect. This workflow allows relatively efficient processing of large amounts of high-resolution imagery, as well as general classification of objects at an early processing stage.Ultimately, our automated analysis workflow will contribute to the preservation management of biodiversity in the German North Sea and Baltic Sea by facilitating the repeated monitoring of bird populations.

Carbon dioxide storage in the deep subsurface of the North Sea is technically feasible and has been practiced for decades beneath Norwegian waters. Under the German North Sea, there are rock formations in which large quantities of carbon dioxide could presumably be stored, too. However, important questions remain, which are to be addressed and answered in the CDRmare research mission – with the aim of enabling a demonstration project for carbon dioxide storage in the geological subsurface of the German North Sea.