Vesna Mačić

Unexpected abundance and long-term relative stability of the brown alga Cystoseira amentacea, hitherto regarded as a threatened species, in the north-western Mediterranean Sea.

Cystoseira amentacea is a Mediterranean endemic alga thriving on very shallow rocky substrates. It has been considered as a threatened species, having experienced a steady decline and is therefore protected by international conventions. The historical distribution of the species has been assessed along the French Mediterranean coast, on the basis of 467 articles and herbarium vouchers. We have produced an accurate map of its current distribution and abundance along 1832 km of coastline, through in situ surveys. C. amentacea was observed along 1125 km of shoreline, including 33% of almost continuous or continuous belt. In most of its range, there is no evidence of loss, except in 4 areas of Provence, French Riviera and Corsica. A significant relation was found between the absence or low abundance of C. amentacea and the vicinity of ports and large sewage outfalls. The status of conservation of the species should therefore be reassessed.

Contemporary genetic structure and postglacial demographic history of the black scorpionfish, Scorpaena porcus, in the Mediterranean and the Black Seas

Understanding the distribution of genetic diversity in the light of past demographic events linked with climatic shifts will help to forecast evolutionary trajectories of ecosystems within the current context of climate change. In this study, mitochondrial sequences and microsatellite loci were analysed using traditional population genetic approaches together with Bayesian dating and the more recent approximate Bayesian computation scenario testing. The genetic structure and demographic history of a commercial fish, the black scorpionfish, Scorpaena porcus, was investigated throughout the Mediterranean and Black Seas. The results suggest that the species recently underwent population expansions, in both seas, likely concomitant with the warming period following the Last Glacial Maximum, 20 000 years ago. A weak contemporaneous genetic differentiation was identified between the Black Sea and the Mediterranean Sea. However, the genetic diversity was similar for populations of the two seas, suggesting a high number of colonizers entered the Black Sea during the interglacial period and/or the presence of a refugial population in the Black Sea during the glacial period. Finally, within seas, an east/west genetic differentiation in the Adriatic seems to prevail, whereas the Black Sea does not show any structured spatial genetic pattern of its population. Overall, these results suggest that the Black Sea is not that isolated from the Mediterranean, and both seas revealed similar evolutionary patterns related to climate change and changes in sea level.

An ecotoxicological approach for the Boka Kotorska Bay (south-eastern Adriatic Sea): First evaluation of lysosomal responses and metallothionein induction in mussels

Mytilus galloprovincialis was used as a biomonitoring organism in Boka Kotorska Bay, a coastal transitional ecosystem in south-western Montenegro. Native mussels were collected in June 2008 at four sites thought to be differently impacted. Biological effects were investigated analysing both generic and specific biomarkers at cellular level (metallothionein content, lysosomal membrane stability, lipofuscin and neutral lipid accumulation, lysosomal structural changes). Trace element levels in mussels were quite low, only Cu and Zn exhibiting slight increases in the two sampling sites of Tivat Bay, the first one in front of a small working dockyard and the other in the water area of a former Naval dockyard. Mussels collected from these sites exhibited the highest values in neutral lipid and lysosomal volume density and the lowest neutral red retention times. Metallothionein content was always low, reflecting the minor body burden of the trace elements and suggesting a non-relevant environmental induction.

Population genomics meet Lagrangian simulations: Oceanographic patterns and long larval duration ensure connectivity among Paracentrotus lividus populations in the Adriatic and Ionian seas

Abstract Connectivity between populations influences both their dynamics and the genetic structuring of species. In this study, we explored connectivity patterns of a marine species with long‐distance dispersal, the edible common sea urchin Paracentrotus lividus, focusing mainly on the Adriatic–Ionian basins (Central Mediterranean). We applied a multidisciplinary approach integrating population genomics, based on 1,122 single nucleotide polymorphisms (SNPs) obtained from 2b‐RAD in 275 samples, with Lagrangian simulations performed with a biophysical model of larval dispersal. We detected genetic homogeneity among eight population samples collected in the focal Adriatic–Ionian area, whereas weak but significant differentiation was found with respect to two samples from the Western Mediterranean (France and Tunisia). This result was not affected by the few putative outlier loci identified in our dataset. Lagrangian simulations found a significant potential for larval exchange among the eight Adriatic–Ionian locations, supporting the hypothesis of connectivity of P. lividus populations in this area. A peculiar pattern emerged from the comparison of our results with those obtained from published P. lividus cytochrome b (cytb) sequences, the latter revealing genetic differentiation in the same geographic area despite a smaller sample size and a lower power to detect differences. The comparison with studies conducted using nuclear markers on other species with similar pelagic larval durations in the same Adriatic–Ionian locations indicates species‐specific differences in genetic connectivity patterns and warns against generalizing single‐species results to the entire community of rocky shore habitats.

Biological Invasions in Conservation Planning: A Global Systematic Review

Biological invasions threaten biodiversity in terrestrial, freshwater and marine ecosystems, requiring substantial conservation and management efforts. To examine how the conservation planning literature addresses biological invasions and if planning in the marine environment could benefit from experiences in the freshwater and terrestrial systems, we conducted a global systematic review. Out of 1149 scientific articles mentioning both ‘conservation planning’ and ‘alien’ or any of its alternative terms, 70 articles met our selection criteria. Most of the studies were related to the terrestrial environment, while only 10% focused on the marine one. The main conservation targets were species (mostly vertebrates) rather than habitats or ecosystems. Apart from being mentioned, alien species were considered of concern for conservation in only 46% of the cases, while mitigation measures were proposed in only 13% of the cases. The vast majority of the studies (73%) ignored alien species in conservation planning even if their negative impacts were recognized. In 20% of the studies, highly invaded areas were avoided in the planning, while in 6% of the cases such areas were prioritized for conservation. In the latter case, two opposing approaches led to the selection of invaded areas: either alien and native biodiversity were treated equally in setting conservation targets, i.e. alien species were also considered as ecological features requiring protection, or more commonly invaded sites were prioritized for the implementation of management actions to control or eradicate invasive alien species. When the ‘avoid’ approach was followed, in most of the cases highly impacted areas were either excluded or invasive alien species were included in the estimation of a cost function to be minimized. Most of the studies that followed a ‘protect’ or ‘avoid’ approach dealt with terrestrial or freshwater features but in most cases the followed approach could be transferred to the marine environment. Gaps and needs for further research are discussed and we propose an 11-step framework to account for biological invasions into the systematic conservation planning design.

Distribution of rare Cystoseira species along the Montenegro coast (South-Eastern Adriatic Sea)

Background and purpose: Multiple studies have shown that Cystoseira species are sensitive to anthropogenic impact, and a decrease in their populations was observed, especially close to urban areas. To better understand status of such endangered and protected species, we studied the distribution of six rare Cystoseira species along the Montenegro coast: C. compressa subsp. pustulata, C. crinita, C. crinitophylla, C. sauvageauana, C. sqarrosa and C. tamariscifolia. Materials and methods: The study is based on field researches conducted through snorkelling and scuba diving along the Montenegrin coast during the period 1998-2009. In addition to the field work, we examined the published data for these species and the unpublished data from prof. Boris Antolić’s field diary. Results: Based on our 12-year-long investigations, we concluded that C. compressa subsp. pustulata, C. crinita, C. crinitophylla and C. sqarrosa are rare and endangered species along the Montenegro coast. Conclusions: The published data for C. sauvageauana is likely mistaken due to incomplete and poorly conserved algal material, while regarding the reference for C. tamariscifolia should be checked if the collected sample was preserved. Furthermore, we noted that the habitat destruction and the proliferation of sea urchin populations have the most dramatic negative impact on the biocenosis formed by such rare and endangered Cystoseira species.

Port Baseline Biological Surveys and seaweed bioinvasions in port areas: What's the matter in the Adriatic Sea?

One of the objectives of the BALMAS project was to conduct Port Baseline Biological Surveys of native and non-indigenous benthic flora in 12 Adriatic ports. Samples of macroalgae growing on vertical artificial substrates were collected in spring and autumn 2014 and/or 2015. A total number of 248 taxa, 152 Rhodophyta, 62 Chlorophyta, and 34 Ochrophyta, were identified. Of these, 13 were non-indigenous seaweeds, mainly filamentous macroalgae, that were probably introduced through hull fouling. Some of these taxa had already been described in the study areas, others were recorded for the first time, a few were no longer detected at sites where they had previously been recorded (e.g. Sargassum muticum). Some other NISS reported for the Adriatic Sea, were not collected at any sampling site (i.e. Caulerpa cylindracea, Codium fragile). Possible reasons for the absence of these species are discussed.

Phytobenthos in the Boka Kotorska Bay: State of Knowledge and Threats

Research of phytobenthos in Boka Kotorska Bay did not start until the second half of the twentieth century and 219 species have been described so far in this area. The highest number of identified taxa in the Bay belongs to the Atlantic phytogeographic element (35.1%), followed by the Mediterranean (18.9%), cosmopolitan (12.2%), and others. Endemic species of the Adriatic Sea are represented with only one species, Fucus virsoides, with the Bay as its southernmost distribution limit. Four species of seagrass are found, and meadows of Posidonia oceanica and Cymodocea nodosa are numerous, especially in the outer part of the Bay. Zostera noltei builds meadows together with the C. nodosa at several locations, while Zostera marina was found at one location only.

Diversity of Vascular Flora of Boka Kotorska Bay

Boka Kotorska represents a unique geomorphologic object in the southern part of eastern coastline of Adriatic Sea. Due to the interesting orography of this bay (surrounded by high mountains representing special micro-centers of floristic diversity in this part of Europe), climate characteristics and pedological substrate, etc., the area of Boka Kotorska Bay may be considered one of the floristic hotspots of Balkan Peninsula. In spite of many centuries of anthropogenic impact, diversity of vascular flora was preserved to a significant percentage. The overview of diversity of vascular flora at Boka Kotorska is a compilation of extensive studies presented in more than 200 scientific papers. However, it must be stated that studies of flora were not systematic. Certain parts of Boka Kotorska area are characterized by excellent level of study and knowledge of floristic diversity, while some other parts are completely neglected and forgotten by researchers. Area of Boka Kotorska includes a high number of Locus classicus units. Literature data have shown presence of 49 endemic taxa, mostly from the Mediterranean–Submediterranean range group. The system of national and international conservation recognizes 47 taxa of vascular plants and among them 26 species belong to family Orchidaceae. The traditional landscape improvement and garden design, present for centuries in area of Boka Kotorska, resulted in extraordinary richness in diversity of ligneous flora.