Fishery and reproductive biology of the spotted sardinella Amblygaster sirm (Walbaum, 1972) exploited along the southern coast of India

stock dynamics of spotted sardinella

Abstract

The study focused on the fishery and biological aspects of the spotted sardinella
Amblygaster sirm (Walbaum, 1972) exploited along the southern coast of India from 2015
to 2020. The summary of the fishery reveals noticeable annual fluctuations in landing, with
peak landings reported from November to March along the coast. The study included fish
with total length (TL) ranging from 149 to 208 mm in males and 152 to 217 mm in females.
The peak in gonadosomatic Index (GSI) in January indicates its spawning season, and Lm50
was estimated at 172 mm TL in females. The sex ratio (F: M) was determined at 1:1.2, with
males dominating most months. Fecundity ranged from 11632 to 43200 eggs per spawning.
Five stages of maturity in A. sirm were identified through external analysis of gonads. Seven
histological ovarian stages of A.sirm were recorded, providing a primary reference for
future studies. These findings aim to assist fishery managers and policymakers in adopting
effective management practices for the sustainable harvesting of this resource.

Keywords:
Amblygaster sirm, Gonadosomatic index, Sex ratio,
Fecundity, Lm50, Histology