Study of reproductive characteristics of white bream, Blicca bjoerkna (Linnaeus, 1758) in Anzali Wetland

Abstract

Introduction: The study carried out in reproduction status project of commercial fishes of
Anzali wetland from April 2016 until March 2017.
Material & Methods: Samples were caught using electroshocker in different points of studied
area.
Results: The studied adult males (n=173) weight varied between 1.08 and 33.22 with an
average of 7.12±4.06g and adult females (n=271) between 0.71 and 59.9 with an average of
12.66±9.16g. Total length were measured between 45.5 and 136 with an average of
80.02±14.03mm in adult males and between 41.3 and 166 with an average of 92.81±22.06mm in
adult females, too. Age composition was from 2 to 11 and 1 to 15 years old for adult males
(n=57) and females (n=130), respectively. Adult males and females formed 38.96% and
61.04% of adults. Monthly average of gonado-somatic index was determined 1% in August
and 13.7% in April with an annual average of 6.54±7.08%for adult females. Spawning period
of the fish species was determined on basis of gonado-somatic index and composition of gonad
maturity stages of adult females from April to July. Absolute fecundity of studied fish (n=16)
was calculated 3805-11483 with an average of 6898.1±1997.89 eggs and average of egg
diameters was 0.9±0.1 mm.
Conclusion: Although this fish has no economic value but this species is caught in Anzali
wetland for consumption. Due to its Reproduction season, its overfishing should be avoided.