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Between 2007 and 2022, 112 specimens of newborn and young pelagic sharks were recorded in the waters of Tuscany Region, in the South Ligurian–North Tyrrhenian Seas (north-western Mediterranean basin). The sharks belonged to the Carcharhinus plumbeus (n = 14), Prionace glauca (n = 66), Isurus oxyrinchus (n = 16), Mobula mobular (n = 5) Alopias vulpinus (n = 7) and Hexanchus griseus (n = 4) species. Each animal was correctly identified thanks to the photographs or videos collected. All specimens were incidentally captured with set nets in inshore shallow waters, except bluntnose six-gill sharks, which were bycatch of deep-water bottom-trawl fishery. Body mass, sex, total length and biometric measurements were recorded in 34 baby sharks following the Mediterranean Large Elasmobranches Monitoring (MEDLEM) protocol. The presence of very evident and often non-healed umbilical scar confirmed that some of the sample specimens were newborn. Further confirmation came from the comparison between the total length observed and the size at birth known for the sampled species as reported in the literature. Some baby sharks were preserved in the Museums of Natural History of Pisa and Florence University collections. The importance of the coastal area studied as a possible shark nursery is discussed.

Bottlenose dolphin Tursiops truncatus (Montagu, 1821) is a cosmopolitan species; it is found in all tropical and temperate coastal waters of the world. The bottlenose dolphins in the Mediterranean Sea mainly show coastal habits, which often lead it to interact with fishing activities. In this study, first data on the diet of specimens of T. truncatus stranded in Tuscany, north-western Mediterranean, are provided. The stomachs contents of thirty-five bottlenose dolphins were analysed; this allowed characterising the main aspects of the trophic spectrum of this coastal cetacean.

Per- and poly fluoroalkylsubstances (PFAS) were measured in liver,muscle, blood and brain of 26 stripped dolphin Stenella coeruleoalba stranded along Tuscany coasts (Italy), from 2020 to 2022. Using high performance liquid chromatography coupled with high resolution mass spectrometry 18 target were quantified in each sample. PFOS, PFHxS, FOSA were found in all samples with PFOS blood concentration level ranging from some tens to some hundreds of µg/kg. The concentrations follow the trend PFOS>FOSA>PFHxS and the PFOS concentration appears to be inversely proportional to the weight of the animals.

A specimen of Synagrops japonicus was collected in the north-western Mediterranean during an exploratory cruise using bottom trawl nets, aimed at the evaluation of possible consequences of lost- at-sea drums containing toxic materials. The discovery of this specimen follows the first record that occurred in the same area 28 years previously, fished by a bottom trawler in the waters of Portofino (Genoa, Italy) in 1987. The morphometric and meristic details of the new specimen are provided. The presence of this individual in the north-western portion of the Mediterranean is likely related to an accidental transport of larvae via ballast water by ships coming from outside the Mediterranean basin., Uzorak Synagrops japonicus sakupljen je u sjeverozapadnom Mediteranu tijekom istraživačkog krstarenja pridnenim povlačnim mrežama, s ciljem procjene mogućih posljedica izgubljenih u moru bubnjeva koje sadrže otrovne materijale. Otkriće ovog primjerka slijedi prvi zapis koji se dogodio na istom području prije 28 godina, a primjerak je bio ulovljen pridnenom koćaricom u vodama Portofina (Genova, Italija) 1987. godine. Navedeni su morfometrijski i meristički detalji novog uzorka. Prisutnost ove jedinke u sjevero- zapadnom dijelu Sredozemnog mora je vjerojatno povezana sa slučajnim transportom ličinki balast- nom vodom u brodovima koji dolaze izvan mediteranskog bazena.