BIOLOGY, SPATIAL-DISTRIBUTION AND POPULATION-DYNAMICS OF LEPIDOTRIGLA-CAVILLONE (PISCES, TRIGLIDAE) IN THE CENTRAL TYRRHENIAN SEA

Specimens of Lepidotrigla cavillone (the large-scaled gurnard) were co llected in the Central Tyrrhenian Sea during trawl surveys carried out in April-May and September 1985, 1986, 1987, 1994, and in October 199 5. The species was fished between 30 and 200 m depth. A significant si ze-depth relationship (p < 0.001), was observed for juveniles (S.L. < 7 cm) and adults: the former migrated deeper from the coastal nursery, at the end of the first year of life; the latter moved shallower towa rd the spawning grounds at 60-100 m depth. Principal Component Analysi s, indicated gonadal development as the main factor affecting L. cavil lone depth-size relationships. Mature females were observed with signi ficantly higher abundance (p < 0.001) at depth of 80-100 m. Large-scal ed gurnards accomplished more than half of their growth during the fir st two years. Reduction of growth coincided with attainment of sexual maturity. An increase of the mesh size towards the legal size may brin g the age at first capture from 1.5 years up to the age of first matur ity (second year) improving current Y/R. (C) 1997 Elsevier Science B.V .