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Book Reference Environmental impacts of offshore wind farms in the Belgian part of the North Sea: Attraction, avoidance and habitat use at various spatial scales
Located in Library / RBINS Staff Publications 2021
Inbook Reference Offshore renewable energy development in the Belgian part of the North Sea – 2021
Located in Library / RBINS Staff Publications 2021
Inbook Reference Blue mussel Mytilus edulis as habitat provider on offshore wind turbine foundations
We compare the species composition of the early (mussels not prevalent) and mature (mussels prevalent) subtidal colonizing communities at offshore windturbine foundations with special attention to the mobility and habitat preferences of the colonizing species. We identified 47 species belonging to nine different phyla from the samples of the mature community, including 21 species unique to the secondary substratum provided by the mussel shell, all of them are sessile species. Only 17 of the 37 species identified from the early subtidal colonizing community were present in the mature community. The main phyla present in both the early and mature samples were Mollusca, Arthropoda, and Annelida. Our findings confirm the hypothesis that mussels counteract the impoverishment of total species richness on wind turbines, caused by the abundant presence of Metridium senile in mature artificial hard substratum communities by providing secondary substratum for colonization by. sessile and hemi-sessile epifauna. The species assemblage found on these mussels is different from the one previously found on the piles, and only seventeen species (~36%) present in the mature community were already present in the first year after installation. In 2020, all bryozoan species (7) were exclusively observed on the secondary substratum provided by the shells of the mussels. However, these species were previously encountered on the scour protection or on the shells of other bivalves. This may be due to the fact that the secondary substratum provided by the mussels differs in physical properties (e.g., microhabitat complexity) from the primary (vertical) substratum of the pile.
Located in Library / RBINS Staff Publications 2021
Inbook Reference Effects of the use of noise-mitigation during offshore pile driving on harbour porpoise (Phocoena phocoena)
In recent years, noise-mitigation technology became more efficient and noise levels during pile driving were reduced significantly. Using passive acoustic monitoring (PAM) datasets from 2016 (Nobelwind construction – no noise mitigation) and 2019 (Northwester 2 and SeaMade construction – Double Big Bubble Curtain) we analyse whether noise mitigation measures applied during the construction of offshore wind farms influenced the likelihood of detecting harbour porpoise (Phocoena phocoena) during pile driving in the Belgian part of the North Sea (BPNS). Exploratory analyses indicate reductions to the spatial and temporal extent of avoidance of the construction area by porpoise when noise mitigation is applied. Without noise mitigation, mean detection rates of porpoises reduced up to 15-20 km from the pile driving location. With noise mitigation however, mean detection rates of porpoises reduced to a lesser extent and this reduction mainly took place at 0-10 km from the pile driving.
Located in Library / RBINS Staff Publications 2021
Article Reference Subtidal Natural Hard Substrate Quantitative Habitat Mapping: Interlinking Underwater Acoustics and Optical Imagery with Machine Learning
Subtidal natural hard substrates (SNHS) promote occupancy by rich benthic communities that provide irreplaceable and fundamental ecosystem functions, representing a global priority target for nature conservation and recognised in most European environmental legislation. However, scientifically validated methodologies for their quantitative spatial demarcation, including information on species occupancy and fine-scale environmental drivers (e.g., the effect of stone size on colonisation) are rare. This is, however, crucial information for sound ecological management. In this investigation, high-resolution (1 m) multibeam echosounder (MBES) depth and backscatter data and derivates, underwater imagery (UI) by video drop-frame, and grab sediment samples, all acquired within 32 km2 of seafloor in offshore Belgian waters, were integrated to produce a random forest (RF) spatial model, predicting the continuous distribution of the seafloor areal cover/m2 of the stones’ grain sizes promoting colonisation by sessile epilithic organisms. A semi-automated UI acquisition, processing, and analytical workflow was set up to quantitatively study the colonisation proportion of different grain sizes, identifying the colonisation potential to begin at stones with grain sizes Ø ≥ 2 cm. This parameter (i.e., % areal cover of stones Ø ≥ 2 cm/m2) was selected as the response variable for spatial predictive modelling. The model output is presented along with a protocol of error and uncertainty estimation. RF is confirmed as an accurate, versatile, and transferable mapping methodology, applicable to area-wide mapping of SNHS. UI is confirmed as an essential aid to acoustic seafloor classification, providing spatially representative numerical observations needed to carry out quantitative seafloor modelling of ecologically relevant parameters. This contribution sheds innovative insights into the ecologically relevant delineation of subtidal natural reef habitat, exploiting state-of-the-art underwater remote sensing and acoustic seafloor classification approaches.
Located in Library / RBINS Staff Publications 2021
Article Reference 4DEMON: Integrating 40 Years of Data on PCB and Metal Contamination in Marine Sediments of the Belgian Part of the North Sea
The assessment of historical data is important to understand long-term changes in the marine environment. Whereas time series analyses based on monitoring data typically span one or two decades, this work aimed to integrate 40 years of monitoring and research data on polychlorinated biphenyls (PCBs) and metals in the Belgian Part of the North Sea (BPNS). Multiple challenges were encountered: sampling locations changed over time, different analytical methods were applied, different grain size fractions were analyzed, appropriate co-factors were not always analyzed, and measurement uncertainties were not always indicated. These issues hampered the use of readily available, highly standardized trend modeling approaches like those proposed by regional sea conventions such as OSPAR, named after the Oslo and Paris conventions.Therefore, we applied alternative approaches, allowing us to include most older historical data that have been obtained during the nineteen seventies and eighties. Our approach included reproducible and quality controlled procedures from data collection up to data assessment. It included spatial clustering, data normalization and parametric linear mixed effect modeling. A Ward hierarchical clustering was applied on recently obtained contaminant data, as the basis for a spatial division of the BPNS into five distinct areas with different contamination profiles. To minimize the risk of normalization errors for the metal data analyses, four normalization approaches were applied and mutually compared: granulometric and nickel (Ni) normalization, next to two hybrid normalization methods combining aluminum (Al) and iron (Fe) normalization. The long-term models revealed decreasing trends for most metals, except zinc (Zn) for which three out of four models showed increasing concentrations in all five zones of the BPNS. Offshore sediments contained the lowest normalized mercury (Hg) and cadmium (Cd) concentrations but high arsenic (As) concentrations. Trend analysis revealed a strong decrease in PCB concentrations in the nineteen eighties and nineties, followed by a slight increase over the last decade. The extended timeframe for contaminant assessment, as applied in this study, is of added value for scientists and policy makers, as the approach allows to detect trends and effects of anthropogenic activities within the marine environment within a broad perspective.
Located in Library / RBINS Staff Publications 2021
Book Reference Field guide to the brittle and basket stars (Echinodermata: Ophiuroidea) of South Africa
Brittle and basket stars (ophiuroids) are one of five extant classes of the phylum Echinodermata and have a fossil record dating back almost 500 million years to the Early Ordovician. Today, they remain diverse and widespread, with over 260 described genera and 2,077 extant species globally (Stöhr et al. 2018), more than any other class of echinoderm. Ophiuroid species are found across all marine habitats from the intertidal shore to the abyss. In southern Africa, the ophiuroid fauna has been studied extensively by a number of authors and is relatively wellknown. The last published review of the southern African Ophiuroidea however was by Clark & Courtman-Stock in 1976. It included 101 species reported from within the boundaries of South Africa. In the 40 years since that publication the number of species has risen to 136. This identification guide includes a taxonomic key to all 136 species, and gives key references, istribution maps, diagnoses, scaled photographs (where possible), and a synthesis of known ecological and depth information for each. The guide is designed to be comprehensive, well illustrated and easy to use for both naturalists and professional biologists. Taxonomic terms, morphological characteristics and technical expressions are defined and described in detail, with illustrations to clarify some aspects of the terminology. A checklist of all species in the region is also included, and indicates which species are endemic (33), for which we report significant range extensions (23), which have been recorded as new to the South African fauna (28) since the previous monograph of Clark & Courtman-Stock (1976) and which have undergone taxonomic revisions since that time (28).
Located in Library / RBINS Staff Publications 2019
Article Reference Revision of the morphology, phylogenetic relationships, behaviour and diversity of the Iberian and Italian ant-like Tachydromia Meigen, 1803 (Diptera: Hybotidae)
Located in Library / RBINS Staff Publications 2021
Article Reference Four new genera and five new species of “Heterocypris” from Western Australia (Crustacea, Ostracoda, Cyprinotinae).
Five new species in four new genera from Western Australia are described. All species have valve characters that are reminiscent of the genus Heterocypris Claus, 1892 and also have similar valve outlines, with highly arched valves. However, all species have a hemipenis morphology that is totally different from the typical form in Heterocypris. In Patcypris gen. nov. (with type species P. outback gen. et sp. nov.), the lateral lobe is large and shaped as a pickaxe, while the medial lobe is divided into two distal lobes. Trilocypris gen. nov. (with type species T. horwitzi gen. et sp. nov.) is characterised by a hemipenis that has three, instead of two, distal lobes. In Bilocypris gen. nov. (with type species B. fortescuensis gen. et sp. nov. and a second species, B. mandoraensis gen. et sp. nov.), the lateral lobe of the hemipenis is spatulate, rather than boot-shaped, and the medial lobe is bilobed. Billcypris gen. nov. (with type species B. davisae gen. et sp. nov.) has a large and sub-rectangular lateral lobe and a pointed medial lobe. We discuss the taxonomic value of the traditional and new morphological characters and speculate that the diversity of this cluster of genera and species may be greater than currently known.
Located in Library / RBINS Staff Publications 2019
Article Reference A subjective global checklist (submitted)of the Recent non-marine Ostracoda (Crustacea).
We present an updated, subjective list of the extant, non-marine ostracod genera and species of the world, with their distributions in the major zoogeographical regions, as well as a list of the genera in their present hierarchical taxonomic positions. The list includes all taxa described and taxonomic alterations made up to 1 July 2018. Taxonomic changes include 17 new combinations, 5 new names, 1 emended specific name and 11 new synonymies (1 tribe, 4 genera, 6 species). Taking into account the recognized synonymies, there are presently 2330 subjective species of non-marine ostracods in 270 genera. The most diverse family in non-marine habitats is the Cyprididae, comprising 43.2% of all species, followed by the Candonidae (29.0%), Entocytheridae (9.1%) and the Limnocytheridae (7.0%). An additional 13 families comprise the remaining 11.8% of described species. The Palaearctic zoogeographical region has the greatest number of described species (799), followed by the Afrotropical region with 453 species and the Nearctic region with 439 species. The Australasian and Neotropical regions each have 328 and 333 recorded species, respectively, while the Oriental region has 271. The vast majority of non-marine ostracods (89.8%) are endemic to one zoogeographical region, while only six species are found in six or more regions. We also present an additional list with ‘uncertain species’, which have neither been redescribed nor re-assessed since 1912, and which are excluded from the main list; a list of taxonomic changes presented in the present paper; a table with the number of species and % per family; and a table with numbers of new species described in the 20-year period between 1998 and 2017 per zoogeographical region. Two figures visualize the total number of species and endemic species per zoogeographical region, and the numbers of new species descriptions per decade for all families and the three largest families since 1770, respectively.
Located in Library / RBINS Staff Publications 2019