Physiological and survival effects of capture of red scorpion fish Scorpaena scrofa (Osteichthyes: Scorpaenidae) by different fishing gears in the Balearic Islands (Western Mediterranean)

摘要

The red scorpionfish Scorpaena scrofa (Linnaeus 1758) is a species of high commercial value in the Western Mediterranean Sea. The market value of S. scrofa is highly related to its size, with smaller individuals, less than 25 cm, sold mixed with other species with a low commercial value with respect to the larger ones. Fishing stress and survival of the specimens of S. scrofa under 25 cm were analysed from captures by fishing line, trammel nets and trawling. Line and trammel net were the most selective fishing gears and both gears had the higher survival rates (100% and 70% respectively), while trawling recorded a 0% survival rate. Superoxide dismutase activity was significantly higher in trawling than the other capture methods and the control group, while the glutathione reductase was lower in trawling and trammel net compared to the control group. No differences were observed in catalase and glutathione peroxidase activities. Malondialdehyde levels were elevated in S. scrofa captured by trawling and trammel net when compared with the controls. Cortisol and lactate were significantly higher in individuals captured by trawling and trammel net respect fishing line and control and glucose levels were increased in individuals captured by trammel net. According to the obtained results, the establishment of measures to favour the release of smaller specimens could contribute to an improvement in the conservation of the stocks of S. scrofa and an increase in the future value of catches.