Reproductive biology of the silver-rag driftfish, Ariomma bondi (TELEOSTEI: ARIOMMATIDAE), in the southeastern Brazilian bight, Brazil

Abstract

Ariomma bondi, the silver-rag driftfish, is a common and abundant species distributed on the shelf break and the upper slope of the Southeastern Brazilian Bight. It is a bycatch discarded by trawlers. It occurs together with and constitutes the prey for important target resources of fisheries. In this study, the reproductive biology of A. bondi was analyzed. Samples were obtained from surveys during 2001-2002. Standard length, weight, sex, and gonadal maturation data were obtained from each fish and used to analyze length frequency distributions, length-weight relationships, and reproductive patterns (sex-ratio, spawning time, and first maturation length). A total of 1,317 individuals were analyzed (standard length between 47 and 185 mm). Males tended to predominate (2:1) in the autumn and summer. The "b†coefficients of the length-weight relationship varied between 2.7963 and 2.9786. Spawning occurred from autumn to spring. Recruitment occurred in the spring, when young were identified in the adult stock, and the first maturation was completed at 100.15 mm standard length. These results were determined using virgin stock, and they are the first regarding A. bondi biology, allowing the understanding of the biology of this species in the target area. The use of the proper technology to avoid/reduce bycatch, the exclusion of fisheries activities in some zones, and the reduction of fishery effort applied to other fish found in deep Brazilian waters will be beneficial to the adult stock of A. bondi.