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The movement of Atlantic bluefin tuna (ABFT) across international boundaries necessitates traceability strategies that would provide more accurate information needed for stock assessment. The Mediterranean Sea is one of the main contributors to ABFT reproduction and global population genetic diversity. In the present study this genetic variability was investigated using 193 samples of adult bluefin tuna from Spain, Turkey and Malta - a longitudinal distance of 3400 km. Analysed were 13 microsatellite loci (eight of which were newly-tested) as genetic markers for the population study. Allele richness measured per locus and sampling location varied from 1.89 to 8.88, taking into account rarefaction. ABFT private alleles were detected in each of the three sampling sites. No significant spatial genetic divergence was found between pairs at the studied locations (F values 0.05). Bayesian clustering analysis corroborated a single and panmictic ABFT population in the Mediterranean Sea. Statistical power analyses indicated a high probability of detecting genetic differentiation and population structure with the sample size and microsatellites used, even at an F value of 0.005. From the results it may be postulated that migrating ABFT during the spawning season are allowing gene flow within the Mediterranean Sea. The complex interplay of movements, including plasticity in the selection of spawning sites with increasing age and environmental conditions, require multiple and new fisheries monitoring and management techniques in order to target the ABFT long-term conservation effectively., Thanks are due The University of Malta for funding the molecular genetics analyses for this ABFT research project in the Mediterranean; Spanish, Turkish and Maltese fishermen assisting in the ABFT sampling in the Mediterranean; Fisheries Department Statistics Officers for forwarding relevant data; and Prof. Rus Hoelzel for constructive advice at various stages of this molecular conservation research project. R. de Stephanis was supported by the Spanish Ministerio de Economía y Competitividad through the Subprograma Juan de la Cierva.

The Maltese Islands have a very active recreational fishing community which may affect the coastal marine ecosystem. Despite this, studies to scientifically document the effects of this activity have been lacking prior to works between July 2012 and June 2017 presented here as a case study. This project, with the aim of collecting long-term data on the characteristics, trends, catches and impacts to fish populations of the recreational shore sport fishery at the national level also involved a pilot study on hobby shore angling. Two thousand five hundred and eighty nine roving-access creel surveys conducted during 132 sport fishing events and 159 catches from hobby fishers were documented with the methodology used also applicable to shore fishing taking place in the Mediterranean and elsewhere. Ninety species belonging to twenty-nine families were documented with the most common being the Sparidae and Labridae. Catch per unit effort was higher for sport fishers with hobby fishers targeting larger fish. Results from this case study go to augment the limited and necessary knowledge on this fishing sector in the Mediterranean. Findings also indicate that recreational fisheries need to be taken into account when considering conservation measures for national, regional and global fisheries management., peer-reviewed

Right in the center of the Mediterranean Sea, the Maltese Islands are well situated for monitoring regional marine biodiversity changes. Among the latter are the increasing alien species coming in through the Suez Channel and the Straits of Gibraltar or brought in through various anthropogenic vectors. The non-native species that turn into invasive do not only affect native marine communities but also the aging and shrinking Maltese small-scale fisheries (SSF) community. SSF are predicted to go extinct and with them their well-known colorful artisanal fishing boats with the eyes of Osiris, which were thought to protect them. In the meantime, large-scale fishing activities have been growing through EU and national legislations, promoting profits over long-term conservation of natural resources and cultural heritage of small fishing communities. This chapter considers the relevance of a changing marine environment and the challenges ahead to safeguard Mediterranean biodiversity, which provides its goods and services to man. The role of well-managed sustainable small-scale fisheries in overcoming some of these challenges is considered., peer-reviewed

In the Mediterranean region, aquatic and riparian habitats are considered amongst the most important for bat survival. These habitats are transient in the Maltese Islands and detailed research on how different bat species cope in these conditions has not been conducted. This paper presents results on the activity of pipistrelle bats across different habitats and seasons using acoustic methods to investigate their foraging habitats in the Maltese landscapes. Regression tree analysis was used to assess the effects of several environmental variables — including climatic conditions, vegetation characteristics, and prey abundance — on foraging activity. Echolocation recordings from pipistrelle bats were obtained during 220 hours of active monitoring between summer 2012 and spring 2013. During each sampling period, a maximum of 36 sites were visited (summer, n = 36; autumn: n = 33; spring: n = 35). Agricultural landscapes, cliffs, shrublands, urban areas, woodland patches, and valleys were all represented by th...

This pictorial-type chapter reviews with extensive imaging examples of the CT imaging appearances of bacterial acute pyelonephritis including typical and unusual renal changes, useful and nonspecific accessory signs, development of intrarenal abscesses and long-term sequelae. Emphasis is placed on appropriate acquisition technique and study review.

The mitochondrial genome, through the application of DNA barcoding, provides a powerful tool for identifying species even when specimens are either incomplete or belong to species that exhibit cryptic diversity. In fisheries management accurate identification of whole or part of the specimens landed is a fundamental requirement for the conservation of species affected directly or indirectly by the fisheries activities. In this study cytochrome c oxidase subunit I (COI) and NADH dehydrogenase subunit 2 (ND2) sequences were used to genetically distinguish 36 elasmobranch species collected from Maltese (Central Mediterranean) commercial fisheries landings. Each species was analysed using these two mtDNA loci where COI (610bp) and ND2 (990bp) efficiently distinguished between the various species studied, leading to the identification of 101 haplotypes, with the intraspecific p-distance ranging between 0 and 0.75% (mean 0.10%, SD ±0.13%). This study enhances the molecular data available on elasmobranchs by providing new ND2 sequences for various species, while providing both COI and ND2 data for poorly studied Mediterranean species including: the large pelagic sharks Alopias vulpinus, A. superciliosus, Carcharhinus altimus, C. plumbeus, Carcharadon carcharias, Isurus oxyrinchus, Prionace glauca and Odontaspis ferox; the smaller demersal sharks Somniosus rostratus, Squatina aculeata, S. oculata and Squalus sp.; and the endemic stingray Dasyatis tortonesei. It also confirmed the landings of species whose identification relies strongly on molecular tools, namely Squalus sp. and D. tortonesei, which are both first confirmed records amongst Maltese fisheries landings. Morphologically, the latter two species, can be easily misidentified with S. blainville and D. pastinaca respectively. Additionally, this study evaluated the genetic differences between different polychromatic forms of Raja clavata, R. radula and Dipturus oxyrinchus. Based on the currently analysed specimens, no significant genetic differences were found between the various forms and thus no further speciation within the species was identified.

Hexanchus griseus is a globally distributed deep-water shark species. It inhabits tropical and temperate waters throughout the world, including the Mediterranean Sea where it is by-caught by small-scale fisheries in the region. In this study, we analysed the genetic variation of H. griseus specimens collected from different areas within and outside the Mediterranean region, to assess its genetic connectivity. The mitochondrial DNA (mtDNA) sequence analysed in this study ranged from cytochrome b to 16S rRNA genes including the control region, the 12S rRNA gene and the interspersed tRNA genes in the region, covering a total of 3731 to 3914 nucleotides. Results have shown that this species exhibits geographically distinct maternal lineages, indicating population structure along geographical ranges. These findings reveal population subdivisions not only between the Pacific Ocean and the Atlantic Ocean, but also within the oceans and on a smaller scale within the Mediterranean Sea. This highlights the need to consider each population subdivision separately when designing management plans for the conservation of this species.

Research and monitoring of coastal habitats and biodiversity is increasingly contributing to the discovery of new alien species, which highlights the use of long-term monitoring for timely assessment and management due to marine environmental changes. Research work undertaken through coastal snorkelling surveys and working with fishermen allow for additional monitoring effort to record biodiversity changes and new alien species presence. One such new alien fish species was observed during spring snorkelling research while a specimen was collected in August 2016 to undertake detailed morphological, meristic and genetic analyses. Mitochondrial DNA barcoding analyses were undertaken to confirm the species' identity as the family Holocentridae is composed of a number of species that have very similar and overlapping morphological characters which may lead to misidentification. This research led to the identification of the first record of a specimen of Longjaw squirrelfish, Holocentrus adscensionis (Osbeck, 1765), in the Mediterranean Sea. This is a subtropical reef-associated species native to the Atlantic Ocean and may compete with native Mediterranean reef species., peer-reviewed

This paper presents morphometric and genetic barcoding analyses of the first record of the Cocoa Damselfish, Stegastes variabilis in the Mediterranean Sea. A single specimen was captured from Senglea waterfront, Malta (Central Mediterranean) on the 15th of September 2013. The species is non-indigenous in the Mediterranean, as it is native to the tropical Western Atlantic. Apart from undertaking identification through meristics and morphometric measurements of the specimen, genetic analyses of the 3410 bp mtDNA genes were carried out to confirm the species’ identity. The latter was useful given that the genus Stegastes is known to be composed of morphologically very similar species, with variable colour patterns., peer-reviewed

Background: Alien fish species are increasing in the Mediterranean Sea, urging closer monitoring of coastal habitats and biodiversity towards achieving timely assessment and management. Among the alien fish species found in Maltese waters there are members of the Abudefduf genus. Methods: Research work undertaken with the cooperation of fishermen allows for additional monitoring effort to record the presence of alien species and their possible impacts. One such alien fish specimen collected from Maltese waters in January 2014 was studied through morphological, meristic and genetic analyses. Mitochondrial DNA barcoding analyses were undertaken to confirm the species' identity given that the specimen found belonged to the genus Abudefduf which is composed of a number of congeners that have similar morphological characters. Results and conclusion: This research led to the identification of the first record of the African Sergeant, Abudefduf hoefleri (Steindachner 1881) (Perciformes: Pomacentridae), in the Mediterranean Sea. This alien tropical species is native of the East Atlantic and may aggressively compete with native Mediterranean reef species for territories and resources., peer-reviewed