New biological data on Fistularia commersonii in the central Mediterranean Sea
Preliminary data on age, growth and diet of bluespotted cornetfish Fistularia commersonii Rüppell, 1838 (Fistulariidae) in the central Mediterranean Sea are provided. In the study area, this invasive Lessepsian fish showed piscivorous behaviour, focusing mainly on labrids, clupeids and sparids. Prey composition suggests that bluespotted cornetfish explores various habitats for hunting. Prey fishes were mainly juveniles and their size showed positive correlation with predator size. Estimated by vertebrae readings, ages of bluespotted cornetfish, having sizes from 73.0 to 107.5 cm total length, ranged from 2 to 4 years; these are the first estimates of age for this species. The parameters of von Bertalanffy growth curves were L∞ = 102.39 cm, k = 0.49 year-1, t0 = –0.57 years. The analysis of growth rates indicates that bluespotted cornetfish is a fast-growing species. Growth performance index was Φ’ = 3.71, and weight-length relationship, W = 0.0001 x TL3.372 (R2 = 0.857), described positive allometric growth of F. commersonii.