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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.

Cetaceans can be considered good natural samplers of biodiversity due to the different hunting strategies they adopt. In this study, the stomach contents of 28 Tursiops truncatus (15 females and 13 males), stranded along Tuscany coasts, NW Mediterranean, between 2008 and 2021, were analyzed. The prey items were identified at the lowest taxonomic level possible, and assessed in terms of abundance, weight, and frequency of occurrence. The index of relative importance (IRI) was also computed. Overall, 2201 bony fishes and 406 cephalopods were identified. The trophic spectrum resulted in high diversity (69 taxa) and the prey species, 53 fishes and 16 cephalopods, live at different levels of the water column. Predation was mainly based on European hake, Merluccius merluccius (%IRI 26.9), and conger eel, Conger conger (%IRI 25.1). The abundant presence of nocturnal species, such as Conger and Ophidion, indicates the nocturnal hunting activity of the bottlenose dolphin. Furthermore, evidence is presented of the dolphins’ ability to capture fish at night, taking advantage of the sound produced by these fish to locate them. Diet did not show any statistical differences among sexes, except that females preyed upon a significantly higher quantity of octopods than males.