On the swarming of Creseis acicula (Rang 1828) (Mollusca, Gastropoda) in the Western Arabian Gulf

An incidental swarming event of a zooplankton species took place in the anchorage area of Ras Tanura (Western Arabian Gulf), between June 10th and 13th 2020, causing serious problems to the anchored vessels. Examination of the samples collected from the clogged water pump of a vessel showed that the swarming was caused by the gastropod species Creseis acicula. Incidentally, it happens to be the first documented report on planktonic Gastropoda swarming in the Saudi waters of the Arabian Gulf. The swarming lasted only 2-3 days. Examination of the satellite images before, during, and after the swarming event indicated some changes in the color patterns of Ras Tanura surface waters, which could be linked to the swarm event. Due to bad weather conditions during and after the swarm period, it was not possible to collect seawater samples from the anchorage area and hence it was not possible to confirm whether this event could be linked with an algal or cyanobacterial bloom, as previously reported in another area of the Indian Ocean. Although most of the studies that reported C. acicula swarming indicated that this phenomenon is a natural one rather than being caused by external factors, some general precautionary/mitigation measures were proposed. Further studies and field observations are needed to better understand the causes of sea slug swarming and to avoid the issues it can cause to vessels, as it happened in the Western Arabian Gulf

Associated fauna of the fan shell <em>Pinna nobilis</em> (Mollusca: Bivalvia) in the northern and eastern Tunisian coasts

Epifaunal communities associated with the fan shell Pinna nobilis Linnaeus, 1758 along the Tunisian coastline were investigated. Both univariate and multivariate analysis were done at different spatial scales within five populations located at different localities, three from northern and two from eastern Tunisia. The size of Pinna did not appear as the main factor affecting the structure of the associated biota, which seemed to be more influenced by (a) marine-lagoon and (b) biogeographic gradients. Patterns of similarity of sessile sclerobionts and motile epifauna were clearly different. The former assemblage best replied to lagoon-sea gradient and to locality, with three real clusters at 40%, whereas the latter assemblage scattered widely in a non-metrical MDS plane, with two real clusters only at 20% similarity. The spatial turnover of motile species was ten times higher than that of sessile species at a small spatial scale, being less affected by Pinna size, and three times higher though invariant at a large geographic scale. On the other hand, β-diversity of sessile species appeared to be more influenced by latitudinal (climatic) gradient at a large scale, being higher in the northern than in the eastern communities. Analysis of taxonomic (dis)similarity of the whole community detected these two sources of environmental (lagoon-sea gradient) and biogeographic (lati-longitudinal gradient) variation, although each phylum showed its peculiar pattern. In terms of Dajoz's constancy index the majority of associated communities were dominated by rare species, and within the majority of epifaunal assemblages, the most abundant sessile epizoobiont was a bivalve mollusc. The sessile epifauna was dominated by active filterers, which led to a possible existence of trophic competition between the host and the sedentary epizoites, since both basibionts and sclerobionts occupy the same trophic niche. The fan shell played an important ecological role, providing new hard substrate to colonise, increasing the spatial heterogeneity for the surrounding soft-bottom communities, and contributing to the overall increase of the local biotope complexity level

Ecology, life history, and fisheries potential of the flathead lobster (Thenus orientalis) in the Arabian Gulf

This study, which included examination of the distribution and life history and a stock assessment of the flathead lobster (Thenus orientalis), is the first of its kind in the waters of Saudi Arabia in the Arabian Gulf, also known as the Persian Gulf. The flathead lobster is widely distributed in this region, although it is more abundant in the central and northern Arabian Gulf. Carapace lengths at 50% and 95% maturity are 59 and 65 mm for females and 58 and 71 mm for males. The fecundity of 4 berried females ranged from 26,000 to 76,000 eggs per spawning, and the fertilization rate exceeded 97%. Length-frequency data were consistent with just 2 cohorts, indicating that this species has a short life span and high growth coefficient (K=0.846 year(-1)). Large fishing boats (called dhows) accounted for more than 98% of the total landings. Estimates of natural mortality rates from use of generalized depletion models have high statistical precision and a magnitude compatible with short life history. In addition, abundance levels estimated with the depletion model are sufficient to support a sustainable small-scale fishery either as bycatch of shrimp trawlers or as a resource targeted with specialized gear. A targeted fishery for flathead lobster could be set during the off months of the shrimp trawl fishery (February-July), reducing interference with the reproduction cycle.info:eu-repo/semantics/publishedVersio

Trace element levels in the muscles of three tern species (Aves: Laridae) from the western Arabian Gulf: environmental assessment and implications for conservation

In the Arabian Gulf (called also Persian Gulf; hereafter 'the Gulf'), Jana and Karan Islands are recognized as one of the most Important Bird Areas in the region. Many migratory breeding seabirds, like the Greater Crested Tern Thalasseus bergii, White-cheeked Tern Sterna repressa and Bridled Tern Onychoprion anaethetus, depend on these islands during the breeding season. However, these aquatic wildlife species are suffering from intensified urban and industrial coastal development and various contamination events including wars and related oil spills. In this study, we used these three piscivorous top predator birds to analyse the levels of 19 trace elements (TEs; i.e. Al, As, Ba, Ca, Cd, Co, Cr, Cu, Fe, Hg, K, Mg, Mn, Na, Ni, Pb, Sr, V and Zn) in 15 muscular tissue samples from Jana and Karan Islands. PERMANOVA analysis showed no difference in contamination profile between sites nor between species probably due to their spatial and ecological proximity and therefore similar levels of exposure to TEs. Comparing these levels with existing literature, our results showed no particular concern for all elements, except for Al (maximum values recorded = 116.5 mu g g-1 d.w.) and, in two samples, Ba (33.67 mu g g-1 d.w.) and Pb (5.6 mu g g-1 d.w.). The results can be considered as an initial step for supplementary evaluations with a larger number of samples and specified time intervals for the collection of specimens. This study provided baseline information on the pollution status of these two ecologically important sites which require a continuous biomonitoring programme

Diversity, distribution, and density of marine mammals along the Saudi waters of the Arabian Gulf: update from a multi-method approach

Despite the important role of marine mammals in marine ecosystems and the imperative for their conservation, there is still a great lack of information on the diversity, distribution, and density of these animals in the Saudi waters of the Arabian Gulf. To fill this gap, an integrative data-collection approach including fishermen’s questionnaires, opportunistic sighting reports, and directed boat-based surveys, was undertaken between 2016 and 2020, leading to the first scientific report of marine mammal diversity, distribution, and density in the region. The results of the different approaches carried out during the study confirmed a high diversity of cetaceans on the west coast of the study area, with bottlenose dolphins (Tursiops aduncus), humpback dolphins (Sousa plumbea) and dugongs (Dugong dugon) as the most common species. While the two dolphin species were found to be widely distributed in both coastal and offshore waters, D. dugon appears to occur exclusively in coastal waters in the southern part of the study area, mainly in the Gulf of Salwah. The presence of both species of dolphins increased during the summer months and in the vicinity of the numerous oil and gas facilities in this region. The distribution of the observed dolphins was found mostly within a 10–20 km radius around each facility. Other cetacean species observed less frequently in the area include Bryde’s whale (Balaenoptera edeni), killer whale (Orcinus orca), common dolphin (Delphinus delphis) and finless porpoise (Neophocaena phocaenoides). Regarding the density of marine mammals in the region, boat-based surveys confirmed the results of fishermen’s questionnaires and reports of opportunistic sightings, with bottlenose and humpback dolphins being the most abundant species. These results provide a baseline for policies oriented to the conservation of mammals in the Saudi waters of the Arabian Gulf.info:eu-repo/semantics/publishedVersio

Hurdles and opportunities in implementing marine biosecurity systems in data-poor regions

Managing marine nonindigenous species (mNIS) is challenging, because marine environments are highly connected, allowing the dispersal of species across large spatial scales, including geopolitical borders. Cross-border inconsistencies in biosecurity management can promote the spread of mNIS across geopolitical borders, and incursions often go unnoticed or unreported. Collaborative surveillance programs can enhance the early detection of mNIS, when response may still be possible, and can foster capacity building around a common threat. Regional or international databases curated for mNIS can inform local monitoring programs and can foster real-time information exchange on mNIS of concern. When combined, local species reference libraries, publicly available mNIS databases, and predictive modeling can facilitate the development of biosecurity programs in regions lacking baseline data. Biosecurity programs should be practical, feasible, cost-effective, mainly focused on prevention and early detection, and be built on the collaboration and coordination of government, nongovernment organizations, stakeholders, and local citizens for a rapid response.This work resulted from a workshop organized at the King Abdul- lah University of Science and Technology and sponsored under the Support for Conferences and Workshops Program. We would like to thank the admin support of the Red Sea Research Cen- ter team, IT, and teachers and students from the KAUST schools who participated in some outreach activities. We thank Ana Bi- gio for the artwork presented in this article (figures 1–4). GS was supported by the European Social Fund, under project no 09.3.3- LMT-K-712, the “Development of Competences of Scientists, other Researchers and Students through Practical Research Activities” measure, grant agreement no. 09.3.3-LMT-K-712–19-0083

“New Alien Mediterranean Biodiversity Records” (November 2021)

This Collective Article includes records of 29 alien and cryptogenic species in the Mediterranean Sea, belonging to eight Phyla (Rhodophyta, Ochrophyta, Cnidaria, Annelida, Mollusca, Arthropoda, Echinodermata, and Chordata) and coming from 11 countries. Notes published here can be divided into three different categories: occupancy estimation for wide areas, new records for the Mediterranean Sea, and new records of species expanding within the Mediterranean Sea. The first category includes a visual survey held along the coastline of Peloponnese (Greece), which yielded records of 15 species. The second category includes the first Mediterranean records of the Coho salmon Oncorhynchus kisutch (Greece) and of the Arabian monocle bream Scolopsis ghanam (Tunisia). The third category includes new records for countries (Ganonema farinosum in Malta, Cassiopea andromeda in Libya, Cingulina isseli in Greece, Okenia picoensis in Italy, Callinectes sapidus in Slovenia, Charybdis cf. hellerii in Malta, Urocaridella pulchella in Cyprus, Ablennes hians and Aluterus monoceros in Lebanon, and Fistularia petimba in Greece and Lebanon), new records for MSFD areas or regional seas (Septifer cumingii in the Greek Ionian Sea and F. petimba in the Marmara Sea), and confirmation of old, doubtful, or spurious records/statements (Branchiomma luctuosum in Tunisia, Thalamita poissonii in the Saronikos Gulf, and Pterois miles in Albania). Noteworthy, the three new records of F. petimba suggest that it may soon spread further in the Mediterranean Sea, as already happened for its congeneric Fistularia commersonii. Distributional data reported here will help tracing colonization routes of alien species in the basin and may facilitate the development of mitigation measures

New records of rare species in the Mediterranean Sea (December 2022)

© 2022, Los autores. This manuscript version is made available under the CC-BY-NC 4.0 license http://creativecommons.org/licenses/by-nc/4.0/. This document is the Published version of a Published Work that appeared in final form in Mediterranean Marine Science. To access the final edited and published work see https://doi.org/10.12681/mms.32369This Collective Article presents information on 20 taxa belonging to five (5) Phyla: Cnidaria (2), Mollusca (8), Arthropoda (4), Echinodermata (1) and Chordata (5) recorded from the Alboran Sea to the Levantine Sea. These new records were found in seven (7) different ecoregions as follows: Alboran Sea: new record of the rare football octopus Ocythoe tuberculata in the harbour of Algeciras (Spain); Western Mediterranean Sea: first record of the isopod Arcturinella deltensis in the Ligurian Sea, and the third in the whole Mediterranean Sea; third Mediterranean site for the Muricidae Coralliophila ahuiri along the Italian coasts (Alghe- ro); first and westernmost record of the goby Corcyrogobius liechtensteini from the Iberian Peninsula; new record of the sea slug Glaucus atlanticus from the coast of the Iberian Peninsula; first and easternmost record of Holothuria (Vaneyothuria) lentiginosa lentiginosa along the Italian coasts; Tunisian Plateau/Gulf of Sidra: seventh record of the oceanic squid Thysanoteuthis rhombus in Tunisia, and first for the Gulf of Gabes. Ionian Sea: second occurrence of the Atlantic tripletail Lobotes surinamensis in the Ionian Sea and first record from the Strait of Messina area; new record of the rare sea elephant Pterotrachea coronata from the Strait of Messina; Adriatic Sea: first record of a facies of football ascidian Diazona violacea in the South Adriatic Sea (Tremiti Island, Italy); two records of the sevengill shark Heptranchias perlo in Croatian waters after more than 70 years of absence of documented records in this area; first known occurrence of the nudibranch Jalonus hyalinus in Slovenian waters and also the first known occurrence of this species in the Adriatic Sea; first record of the nudibranch Okenia elegans in Slovenian waters; Aegean Sea: First record of the parasitic isopod Nerocila milesensis along Greek coasts (Crete island) as well as the second record world- wide; additional record of the brachyuran Paragalene longicrura collected from the Saronikos Gulf (Greece); first record of the siphonophore Rhizophysa filiformis in Greek waters as well as the second record of this species in the eastern Mediterranean basin; new record of the rare and protected angelshark Squatina aculeata along Turkish coasts; Levantine Sea: first record of the marine amphipod Caprella andreae in the Levantine Mediterranean shore of Israel, based on both morphological and molecular data; first occurrence of the cephalopod Tremoctopus violaceus along Turkish coasts, which confirms its presence in the north-eastern coasts of Turkey; record of a bloom of the thermophilic jellyfish Pelagia noctiluca in the north Levantine Sea

Unpublished Mediterranean and Black Sea records of marine alien, cryptogenic, and neonative species

To enrich spatio-temporal information on the distribution of alien, cryptogenic, and neonative species in the Mediterranean and the Black Sea, a collective effort by 173 marine scientists was made to provide unpublished records and make them open access to the scientific community. Through this effort, we collected and harmonized a dataset of 12,649 records. It includes 247 taxa, of which 217 are Animalia, 25 Plantae and 5 Chromista, from 23 countries surrounding the Mediterranean and the Black Sea. Chordata was the most abundant taxonomic group, followed by Arthropoda, Mollusca, and Annelida. In terms of species records, Siganus luridus, Siganus rivulatus, Saurida lessepsianus, Pterois miles, Upeneus moluccensis, Charybdis (Archias) longicollis, and Caulerpa cylindracea were the most numerous. The temporal distribution of the records ranges from 1973 to 2022, with 44% of the records in 2020–2021. Lethrinus borbonicus is reported for the first time in the Mediterranean Sea, while Pomatoschistus quagga, Caulerpa cylindracea, Grateloupia turuturu, and Misophria pallida are first records for the Black Sea; Kapraunia schneideri is recorded for the second time in the Mediterranean and for the first time in Israel; Prionospio depauperata and Pseudonereis anomala are reported for the first time from the Sea of Marmara. Many first country records are also included, namely: Amathia verticillata (Montenegro), Ampithoe valida (Italy), Antithamnion amphigeneum (Greece), Clavelina oblonga (Tunisia and Slovenia), Dendostrea cf. folium (Syria), Epinephelus fasciatus (Tunisia), Ganonema farinosum (Montenegro), Macrorhynchia philippina (Tunisia), Marenzelleria neglecta (Romania), Paratapes textilis (Tunisia), and Botrylloides diegensis (Tunisia).peer-reviewe