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1) SUMMARY a) Context The improvement of our understanding of ecological processes and the role of biodiversity in the Southern Ocean ecosystems remains a high priority on the research agenda in today’s changing world and is inextricably linked to sustainable development policies on a global scale. Global environmental changes influence species distributions and consequently the structure of communities and ecosystems. Only advances in our knowledge of the Southern Ocean biodiversity and processes important for ecosystem functioning can allow us to address complex evolutionary and ecological questions and enable estimations of the expected change of the biota distribution and composition. Polar regions experience greater rates of global change than any other region in the world. Their biota are highly adapted to the extreme environment they are living in and appear vulnerable to shifts in environmental conditions. Antarctic marine species are especially more sensitive to temperature variation as their physiology is set to a narrow range of temperatures. Also changes in food quality and quantity, together with other environmental shifts such as in pH of the seawater, are likely to impact densities, biomass and community composition but also functional aspects of the Antarctic biota. Because of the key-role of the Southern Ocean for the global ocean system and the growing impact of global environmental change, it is crucial to establish comprehensive baseline information on Antarctic marine biodiversity as a sound benchmark against which future change can be assessed reliably. It is equally important to understand better the ability of taxa to cope with changes in environmental parameters (temperature, pH, ice cover, food quantity and quality) linked to global change, and this from the individual to the community level. Imperative in this approach is to assess how structural and functional characteristics of the biota may be affected by a changing climate. Finally, advanced integrative spatial modelling of the distribution of key species in relation to environmental conditions is needed to predict the future of the marine ecosystems related to climate change. These aspects are addressed in the Bianzo II project by focusing on benthic organisms and communities, specifically representatives from three different size classes of the zoobenthos: Nematoda (meiobenthos), Amphipoda (macrobenthos) and Echinoidea (megabenthos). These three groups are characterised by a high diversity and many of the well over 4000 Antarctic benthic species described so far (Clarke & Johnston, 2003) belong to these taxa. These three selected benthic taxa are also ecologically important in terms of biomass, their role in biogeochemical cycles (C and N) and the trophic role they fulfil in the benthic ecosystem. Furthermore, they are characterised by different biogeographical and diversity patterns, speciation mechanisms, and reproductive and dispersal strategies. Because of these differences and the intrinsic ecological variability between these taxa, it is difficult to assess the extent to which global change will affect the Antarctic benthos in general. Rarely do biodiversity and ecological studies focus on multiple benthic groups. Yet, combining putative size groups in ecological/biodiversity research is imperative to understand the benthic ecosystem as a complex and interactive unity. b) Objectives Climate change and its complex and interactive chain of associated effects will affect the physiology, distribution, phenology, and ontogeny of many Antarctic benthic organisms, but the resulting changes from the species to the community level remain poorly quantified and understood. Individual species may appear vulnerable to environmental shifts or regime changes, but community and ecosystem responses may not act accordingly. Therefore we investigated the biodiversity and responses of the three representative groups of benthic organisms to climate change effects from individual species, over populations, up to the community level During its first phase (2007-2008), BIANZO II aimed at investigating (1) biodiversity patterns of the Antarctic zoobenthos and their causal processes by focussing on the three selected benthic groups (Work package 1: NOWBIO); Furthermore (2) trophodynamic aspects of each of the benthic groups, and their ability to cope with temperature and temperature-related changes (i.e. food composition and availability) but also the effect of pH of the seawater were on the benthos (Work package 2: DYNABIO). In the second phase (2009-2010) of the project, a joint review paper dealing with the effects of global climate change on the Antarctic zoobenthos is being written, based on the results of experiments, field results and literature data. Information collected in previous studies and in the first two work packages of this project was also used to develop a habitat suitability model in order to identify the drivers of benthic distribution patterns and forecast possible changes of benthic communities related to global change (Work package 3: FOREBIO). c) Conclusions i) NOWBIO (1) Benthic biodiversity in new ice free habitats Due to large-scale ice-shelf disintegration events, the Antarctic Larsen A and B areas along the Eastern Antarctic Peninsula recently became ice-free. Our study is the first one to investigate benthic communities and their response to the collapse of ice shelves in this area. At the time of sampling, meiofauna community structure at the inner stations, most remote from the original ice margin, was not or only slightly influenced by colonization, and might be structured by local environmental conditions. Communities living close to the former ice-shelf edge are believed to be at an intermediate or late stage of succession. Densities and diversity here were comparable to those at other more northern Antarctic stations in the Weddell Sea, whereas they were considerably lower at the inner stations. The three echinoid species collected in Larsen A&B areas are good candidates as pioneering species in a changing marine environment. They are known as indirect developers (or at least non-brooders), consistent with high dispersal capabilities. Moreover, this is congruent with the wide Antarctic distribution of these species. These examples stand in contrast to other Antarctic echinoids which are known as direct developers that brood their young and, accordingly, are supposed to present low dispersal capacities. The three Larsen species also display a ‘generalist’ feeding behaviour which can also be considered a characteristic of pioneering species. Furthermore, the symbiotic communities of echinoids in the Larsen area showed a low diversity and a strong similarity with epibionts present on stones, something which has not been observed in other regions so far. These results suggest that ectosymbioses linked to cidaroids could contribute to benthic colonization of the seafloor in these new ice free areas. The Larsen ice-shelf disintegration also led to the discovery of a low-activity methane seep. The observation of elevated densities, subsurface maxima and high dominance of one nematode species was similar to other cold-seep ecosystems world-wide and suggested a dependence on a chemosynthetic food source. However, stable 13C isotopic signals were indicative of phytoplankton-based feeding. This implied that the community was in transition from a chemosynthetic community to a classic phytodetritus feeding community, a temporary ecotone as it were. The characteristic parthenogenetic reproduction of the dominant species is rather unusual for marine nematodes and may be responsible for the successful colonisation by this single species.

The International Council for the Exploration of the Sea (ICES; French: Conseil International pour l'Exploration de la Mer, CIEM) is an intergovernmental marine science organization that brings together the efforts and knowledge of 20 Member States, bordering the North Atlantic and the Arctic Circumpolar Zone, on physical oceanography, marine ecosystems and fisheries management. Nowadays, more than 80 Belgian scientists are directly involved in the work of the 150 bodies and expert groups of ICES, which gather the expertise of more than 1500 scientists yearly, totalling up to 5000 scientists from over 700 marine institutes and organizations over the years. This important and often voluntary dedication of Belgian scientists to the work of ICES deserves more visibility among the Belgian scientific community itself and to policy makers.This is, among others, why the BICEpS initiative was launched in 2018. BICEpS general aim is to offer a platform to the Belgian ICES community to get to know each other, to improve collaboration and share information, and to promote ICES to the wider scientific community in Belgium. BICEpS Annual report 2019 presents the second year of activity of this initiative created to reinforce Belgian ICES people. The report targets marine scientists, marine managers and policy makers. It presents the results of the initiative so far. The report contains the list of Belgian ICES members in 2019 with their membership to the different ICES working groups, and the results of the second BICEpS Colloquium organised on 2 December 2019 and hosted by ILVO in Ghent (Summary of the sessions, abstracts of communications presented and list of participants). The abstracts of the colloquium are supplemented by a separate annex published online which assembles the PowerPoint presentations of the colloquium accessible at http://ices.dk/community/groups/Documents/BICEPS/BICEpS19-PPT-presentations.pdf This report is accessible on the ICES website at http://ices.dk/community/groups/Pages/BICEpS.aspx

Ultraviolet (UV) induced biofluorescence in snakes has been underexplored compared to lizards. This study reports for the first time UV fluorescence in several Pythonidae species, including Morelia viridis, Malayopython reticulatus, and Python regius. Specimens were examined under both white and UV light, revealing that UV fluorescence in these snakes is likely skin-based, induced by chemical compounds rather than bone-based as seen in other reptiles. Notably, Morelia viridis and M. azurea exhibited a golden mustard yellow fluorescence, while Malayopython reticulatus displayed a complex pattern with intense yellow fluorescence. The study also found that UV fluorescence is absent in ethanol-preserved specimens, suggesting the degradation of fluorescent compounds during preservation. These findings contribute to the understanding of UV fluorescence in snakes and highlight the need for further research on its functional significance and the specific molecules involved.

Biofluorescence, the phenomenon where organisms absorb short wavelengths of light and re-emit longer wavelengths, has been documented in various reptile and amphibian groups. This study reports the first observation of UV-induced biofluorescence in the genus Tribolonotus (crocodile skinks), marking the first such report for the family Scincidae. Specimens of Tribolonotus novaeguineae, T. brongersmai, and T. gracilis were examined under UV light, revealing distinct fluorescence patterns. The fluorescence is primarily bone-induced, linked to the presence of osteoderms, although some skin-based fluorescence was also observed, particularly around the eyes. The study suggests potential ecological roles for this fluorescence, such as intraspecific signaling or predator-prey interactions, and highlights the need for further research to understand the functional significance of biofluorescence in these skinks.

Bioclast-stratigraphy, or ecozonation, of the Cretaceous (Santonian - Campanian -Maastrichtian) in South Limburg (the Netherlands) and eastern Belgium. A brief overview is presented of lithological subdivisions that have been published over the years for the Upper Cretaceous sediments (Santonian-Campanian-Maastrichtian) in Belgium, the Netherlands and Germany (Fig. 2). The various Formations and Members with their respective type localities are briefly described, followed by a discussion of bioclasts and bioclasts ecozones. The results of samples from boreholes and outcrops studied for their bioclast content are subdivided into ecozones, such as the ones described previously for the Belgian Campine area (Felder, 1994) (Fig. 3). The bioclast ecozones are compared with the lithological and international subdivi- sions of the Late Cretaceous (Fig. 4 ). In the outcrop area encompassing the southern part of both Limburg provinces and the northern part of Liège province, samples were taken over considerably shorter intervals (0.15-1.00m ) than in the Belgian Campine and the Brabant Massif where the Cretaceous is only accessible by boreholes (3.00-5.00m). Therefore, more peaks and throughs could be distinguished in the relative number of bioclasts. From a comparison of the data it appears that it is possible to correlate the majority of these peaks. Numbers given here to the peaks have been defined as follows: they are preceded by a capital letter (either followed by a lower cast letter or not) to indicate the bioclast group (e.g. F. Foraminifera, B. Bryozoa, Be. Belemnoidae, Br. Brachiopoda, etc.). The letter (or letters) are followed by the Roman numeral of the bioclast ecozone ( e.g. FII, FV, BIV, BV, BeI, BeIII, BrIII, BrIV) in which the peaks are situated. Finally follows an Arab numeral (e.g. FII3, FV3, BIV3, BV3, BeII3, BeIII3, BrII3, BrIV3) to indicate the order of peaks in the ecozone. Previous1y subdivided and numbered units within the ecozones are here maintained. For instance, in the Vijlen Member seven units (Vijlen 0- Vijlen 6) were distinguished and the peaks of foraminifera identified with letters (A up to including L) (Felder & Bless, 1994; Felder, 1997a). The Crinoidea units were also numbered within the ecozones IV and V (CR1 up to and CR10), as were the Pelecypoda units previously distinguished in ecozones IVa, IVb and V (Felder, 1997b). To elucidate matters, the letter P is here added to these Pelecypoda units. The peaks within these Pe1ecypoda units were previously distinguished by x and y. Following this numbering, the Pelecypoda in other ecozones (II, III en VI) are subdivided into a similar way. The separate peaks, however, are distinguished in these newly subdivided units, by using successive Arab numerals. The overviews (Fig. 9, 21, 26, 29 and 30) present an overview of the various ecozones and illustrate the sedimentary variability of the extended Maastricht type area. Résumé Stratigraphie par bioclastes, ou écozonation, dans le Crétacé (Santonien - Campanien -Maastrichtien) de Limbourg (Pays Bas) et de la Belgique orientale. Ce livre présente une revue des subdivisions lithologiques du Crétacé supérieur (Santonien-Campanien-Maastrichtien) en Belgique, aux Pays-Bas et en Allemagne. Les Formations et les Membres ainsi que leurs localités-types sont décrits succinctement suivi d'une discussion sur les bioclastes et leurs écozones. Un inventaire des bioclastes de tous les échantillons de sondages ou d'affleurements a été effectué. Une subdivision en écozones complète celle déjà existante pour la Campine belge (Felder, 1994) (Fig. 3). Les écozones basées sur les bioclastes sont comparées avec les subdivisions lithologiques récentes du Crétacé (Fig. 4). Pour les affleurements de la partie méridionale des provinces du Limbourg et du nord de la province de Liège, des échantillons ont été prélevés à intervalle très court, entre 0.15 et 1.00 m, tandis que pour ceux situés en Campine belge, le prélèvement de cuttings de forage a été effectué entre 3.00 et 5.00 m de sorte qu'un nombre moins important de pics et de creux dans les proportions relatives de bioclastes peuvent y être reconnus. En comparant ces données, il est possible de corréler la majorité des pics. Les numéros donnés aux pics sont définis de la manière suivante: une lettre en capitale (suive éventuellement par une lettre en minuscule) pour indiquer le groupe de bioclastes (par exemple, F=Foraminifera, B=Bryozoa, Be=Belemnoidae, Br=Brachiopoda, etc..), ensuite vient un chiffre romain numérotant les écozones où les pics sont situés (par exemple FII, FV, BIV, BV, BeII, BeIII, BrIII, BrIV, etc.. .) et pour terminer un chiffre arabe indiquant l'ordre de succession des pics dans chaque écozone (par exemple FII3, FV3, BIV3, BV3, Be3, BeII3, BrIII3, BrIV3, etc). Les unités qui par le passé, ont déjà été subdivisées et numérotées dans des écozones sont toujours maintenues. Par exemple, dans le Membre de Vijlen, pour les sept unités (Vijlen 0- Vijlen 6) identifiées, les pics de Foraminifera ont été complétés par des lettres (de A jusqu'à L) (Felder & Bless, 1994; Felder, 1997a). Il en est de même pour les unités de Crinoidea dans les écozones IV et V dont le numérotation se situe entre CR 1 à CR 10 ainsi que pour les unités de Pelecypoda répertoriées antérieurement dans les écozones IVa, IVb et V (Felder, 1997b). Suivant Felder, les pics de Pelecypoda avaient été distinguées par les lettres x et y. Pour compléter le nomenclature utilisée par Felder (1997b), la lettre P est ajoutée à ces unités. Alors que dans les autres écozones (II, III et IV), les pics de Pelecypoda sont subdivisés par l'utilisation de chiffres arabes. Des vues générales (Figures 9, 21, 26, 29 et 30) présentent un plan des différentes écozones et illustrent la sédimentation variable de cette région-type du Maastrichtien. Samenvatting Bioklasten-stratigrafie of ecozonatie voor het Krijt (Santoniaan - Campaniaan -Maastrichtiaan) van Zuid Limburg en oostelijk België. Er wordt een summier overzicht gegeven van de lithologische indelingen die in de loop van de tijd gemaakt zijn van de Laat Krijt-afzettingen (Santoniaan-Campaniaan-Maastrichtiaan) in België, Nederland en Duitsland (fig. 2). De verschillende Formaties en Leden met hun typelokaliteiten worden kort beschreven. Daarna wordt ingegaan op de bioklasten en de onderscheiden bioklasten-ecozones. De resultaten van de monsters uit de boringen en ontsluitingen die onderzocht werden op bioklasten zijn naar hun bioklasten-inhoud ingedeeld in ecozones (fig. 3) zoals ze reeds eerder beschreven werden in de Belgische Kempen (Felder, 1994). De bioklasten-ecozones worden vergeleken met de lithologische- en de internationale indeling van het Laat Krijt (fig. 4). Omdat de monsters uit ontsluitingen in de beide Limburgen en in het Luikse gebied over aanmerkelijk kortere afstanden genomen werden (0. 15 - 1.00 m), dan in de boringen van de Belgische Kempen en het Massief van Brabant (3.00 - 5.00 m), zijn er meer pieken en dalen te onderscheiden in de relatieve hoeveelheden van de bioklasten. Uit een vergelijk van de gegevens blijkt dat het mogelijk is het merendeel van de pieken met elkaar te correleren. De pieken van sommige groepen van bioklasten werden genummerd. De hier gegeven nummers aan de pieken zijn als volgt samengesteld. Ze worden voorafgegaan door een kapitale letter (eventueel gevolgd door een onderkast-letter) om de bioklastengroep aan te duiden (bijv. F. Foraminifera, B. Bryozoa, Be. Belemnoidae, Br. Brachiopoda, enz.). De letter (of letters) worden daarna gevolgd door het Romeinse cijfer van de bioklasten-ecozone (b.v. FII, FV, BIV, BV, Bell, BeIII, BrII, BrIV) waarbinnen de piek gelegen is. Tenslotte volgt achter deze combinatie nog een Arabisch nummer (b.v. FII3, FV3, BIV3, BV3, BeII3, BeIII3, BrII3 en BrIV3) om de volgorde binnen de ecozone aan te geven. De reeds eerder ingedeelde en genummerde eenheden binnen de ecozones blijven hier gehandhaafd. Zo werden in de Kalksteen van Vijlen zeven eenheden (Vijlen 0- Vijlen 6) onderscheiden en de pieken van de Foraminifera genummerd met letters (A t/m L) (Felder & Bless, 1994 en Felder, 1997a). De Crinoidea-eenheden werden ook reeds binnen de ecozones IV en V genummerd (CR 1 t/m CR 10) evenals de Pelecypoda-eenheden in de ecozones IVa, IVb en V (Felder, 1997b). Ter verduidelijking wordt hier voor de nummers van deze Pelecypoda-eenheden een P gevoegd. De pieken binnen deze Pelecypoda-eenheden werden reeds eerder in deze eenheden x en y genoemd. In navolging met deze nummering worden de Pelecypoda in de andere ecozones (II, III en VI) op een soortgelijke wijze in Pelecypoda-eenheden verdeeld. De afzonderlijke pieken worden echter in deze nieuw ingedeelde eenheden van een Arabisch volgnummer voorzien. De overzichten (fig. 9,21,26,29 en 30) geven tenslotte een beeld van de onderlinge relaties tussen de ecozones en laten tevens de sedimentaire verschillen zien die in dit Maastrichts typegebied zijn opgetreden.

AbstraitLes systèmes lacustres subissent de fortes pressions qui ont un impact sur leur biodiversité et les services écosystémiques associés. Cela est particulièrement grave en Afrique de l’Ouest et dans les pays en développement, qui manquent de ressources et de capacités techniques pour l’élimination des déchets, la purification de l’eau, ainsi que de capacités scientifiques suffisantes pour la biosurveillance et la gestion intégrée. La préservation, la surveillance et l'amélioration de la qualité des lacs dans ces pays revêtent cependant une importance primordiale. Dans les pays développés, un ensemble d'indicateurs et d'indices multimétriques ont été intégrés à la biosurveillance et à l'évaluation des lacs. Nous évaluons ici les nombreuses procédures, mesures et indices utilisant les macroinvertébrés comme indicateurs de la qualité des lacs et évaluons leur applicabilité dans les lacs d’Afrique de l’Ouest et, plus généralement, dans les pays en développement. Nous proposons un cadre de suivi basé sur les macroinvertébrés adapté à ces pays, incluant des recommandations pour développer de nouveaux indices et adapter les scores de tolérance des taxons aux conditions locales. Ces travaux soulignent l’importance des macroinvertébrés pour la biosurveillance de la santé des lacs dans les lacs d’Afrique de l’Ouest et, plus généralement, dans les pays en développement.