Abstract

MARTINS, Rodrigo Silvestre  and  SCHWINGEL, Paulo Ricardo. Biological aspects of the Sailfin dory Zenopsis conchifer (Lowe, 1852) caught by deep-sea trawling fishery off southern Brazil. Braz. j. oceanogr. [online]. 2012, vol.60, n.2, pp. 171-179. ISSN 1982-436X.  http://dx.doi.org/10.1590/S1679-87592012000200007.

Biological aspects of sailfin dory, Zenopsis conchifer, were studied from 839 individuals obtained from deep-sea commercial bottom trawling off southern Brazil at depths up to 526 m in 2002 and 2003. Samples included fish from 101 mm Lt and 15 g up to 640 mm Lt and 2,9 g. The sex-ratio was 50% at 150 mm Lt and between 300-350 mm Lt, with females outnumbering males in the remaining size classes. Reproductive activity seems to peak between July and August (austral winter). Size at attainment of 50% maturity (Lt₅₀) was 311 mm Lt in females. The mean length and maturity of the specimens increased with depth, suggesting that larger fish concentrate in deeper waters.

Keywords : Zeidae; size structure; sex ratio; maturity; bathymetry; southern Brazil.