PERMANOVA Analysis.

<p>Permutational multivariate analysis of variance based on the Euclidean dissimilarity measure for presence-absence data. The test was done using 9999 permutations under the reduced model. The group ‘FLUCTUATE’ was excluded from the analysis.</p

List of fish taxa cited by the respondents.

<p>The number of times in which they were assigned to the groups ‘INCREASE’ (‘I’), ‘DECREASE’ (‘D’) and ‘FLUCTUATE’ (‘F’) is reported.</p

Study locations in the Mediterranean Sea.

<p>Study locations in the Mediterranean Sea.</p

Results of the breakpoint structural analysis.

<p>The trend (increase ‘I’, decrease ‘D’ or fluctuate ‘F’), the year of statistically significant change (with CI at the 95% level) and results of the modified F test are showed for the species that contribute significantly in the SIMPER analysis. Confidence interval not shown because outside data time interval;</p>+<p>Increasing in last 10 years.</p><p>Probability of the Sup F <0.001 in all cases.</p

Dynamic of the abundance of ‘SIMPER species’, according to fisher's perceptions.

<p>Trends of relative abundance on a scale from 0 to 5 (see text) of the species contributing mostly to the SIMPER analysis. Bold continuous line: mean relative abundance; dashed green line: null model of no temporal change in relative abundance; dashed blue lines: best fitting local regressions before and after break point; vertical dashed line: breakpoint or year of significant change in the temporal evolution of abundance, with 95% confidence intervals in red brackets.</p

Most important fish taxa in typifying the groups ‘I’ and D by SIMPER analysis.

<p>List of fish taxa in decreasing order of their importance in typifying the groups ‘INCREASE’ (‘I’) and ‘DECREASE’ (‘D’) by SIMPER analysis performed on presence/absence data. Cut off for low contributions: 90.00%. Group ‘I’ average similarity 18.05; Group ‘D’ average similarity 12.51; Group ‘F’ average similarity 15.44.</p><p>*Milazzo,</p>§<p>Linosa and Lampedusa.</p

Percent distribution of fishing methods adopted by the respondents.

<p>Interviewed (Tot N = 32) were both recreational (N = 8, 25%) and professional (N = 24, 75%) fishermen.</p

Genetics of a Lessepsian sprinter: the bluespotted cornetfish, <i>Fistularia commersonii</i>

<div><p>Our current understanding of the mechanisms that lead to successful biological invasions is limited. Although local adaptation plays a central role in biological invasions, genetic studies have failed to produce a unified theory so far. The bluespotted cornetfish, a recent invader of the Mediterranean Sea from the Red Sea via the Suez Canal, provides an ideal case study to research the mechanisms of invasive genetics. Previous genetic work based on mitochondrial markers has shown the genetic diversity of the Mediterranean population was greatly reduced in comparison to the natural population in the Red Sea. In the current study, we expand upon these studies by adding mitochondrial and nuclear markers. Mitochondrial results confirm previous findings. The nuclear marker, however, does not show evidence of reduction in diversity. We interpret these results as either a differential dispersal capability in males and females, or the presence of selection on the invading Mediterranean population.</p></div

Unpublished Mediterranean records of marine alien and cryptogenic species

Good datasets of geo-referenced records of alien species are a prerequisite for assessing the spatio-temporal dynamics of biological invasions, their invasive potential, and the magnitude of their impacts. However, with the exception of first records on a country level or wider regions, observations of species presence tend to remain unpublished, buried in scattered repositories or in the personal databases of experts. Through an initiative to collect, harmonize and make such unpublished data for marine alien and cryptogenic species in the Mediterranean Sea available, a large dataset comprising 5376 records was created. It includes records of 239 alien or cryptogenic taxa (192 Animalia, 24 Plantae, 23 Chromista) from 19 countries surrounding the Mediterranean Sea. In terms of records, the most reported Phyla in descending order were Chordata, Mollusca, Chlorophyta, Arthropoda, and Rhodophyta. The most recorded species was Caulerpa cylindracea, followed by Siganus luridus, Magallana sp. (cf. gigas or angulata) and Pterois miles. The dataset includes records from 1972 to 2020, with the highest number of records observed in 2018. Among the records of the dataset, Dictyota acutiloba is a first record for the Mediterranean Sea. Nine first country records are also included: the alga Caulerpa taxifolia var. distichophylla, the cube boxfish Ostracion cubicus, and the cleaner shrimp Urocaridella pulchella from Israel; the sponge Paraleucilla magna from Libya and Slovenia; the lumpfish Cyclopterus lumpus from Cyprus; the bryozoan Celleporaria vermiformis and the polychaetes Prionospio depauperata and Notomastus aberans from Malta.</p