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Given the poor conservation status of chondrichthyans (sharks, rays and chimeras) and the severe impairments caused by fishing activity in animals that are released, the aim of my research was to investigate energetic and reproductive consequences of fishing-capture stress in chondrichthyans. Results show that animals invest more energy to face the stress and survive, but, when the stress is too severe, a prolonged metabolic depression is triggered, saving the little energy left for life sustenance. However, this reduces energy allocation to pregnancy in viviparous species and, in turn, causes impairments in neonates, possibly impacting neonate survival and population abundance.

The common thresher shark, Alopias vulpinus, has shown a marked decline in abundance in the Mediterranean Sea. Through the analysis of long-term fishery time series (1966–2013), this study highlights that an important driver of the presence of A. vulpinus in the northern Adriatic Sea, one of the most exploited basins of the Mediterranean, is the abundance of its prey, the sardine Sardina pilchardus. From 1997-2013, an annual average of 14 thresher sharks was landed at Chioggia (Italy), the main fish market in the area, mainly from July to October. More than 75% of the landed thresher sharks were sexually immature, with some specimens weighing less than 10 kg, indicating that a high proportion of the catch was composed of small young and newborn individuals. These results support the occurrence of a nursery area in the northern Adriatic Sea, highlighting the need for proper management of A. vulpinus catch in this area., Zabilježen je značajan pad zastupljenosti psa lisice, Alopias vulpinus, u Sredozemnom moru. Analizom dugoročnog vremenskog niza podataka u ribarstvu (1966-2013), ovo istraživanje pokazuje da je važan pokretač prisutnosti A. vulpinus, u sjevernom Jadranu kao jednom od najiskorištenijih bazena na Sredozemlju, obilje njegova plijena srdele, Sardina pilchardus. U razdoblju 1997.-2013. godišnji prosjek ulova psine lisice je iznosio 14 primjeraka donesenih na glavnu ribarnicu u mjestu Chioggia (Italija) i to poglavito od srpnja do listopada. Više od 75% primjeraka ulovljenog psa lisice bili su spolno nezreli, od kojih su neki primjerci imali manje od 10 kg, što ukazuje da je visok udio ulova bio sastavljen od malih nedoraslih jedniki i mlađi. Ovi rezultati podupiru pojavu rastilišta u sjevernom Jadranu, ujedno naglašavajući potrebu pravilnog upravljanja ulovom A. vulpinus u ovom području.