Catch composition and fishing trend of kilka in Iranian part of the Caspian Sea
Publish place: Iranian Journal of Fisheries Sciences، Vol: 7، Issue: 3
Publish Year: 1386
نوع سند: مقاله ژورنالی
زبان: English
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شناسه ملی سند علمی:
JR_JIFRO-7-3_006
تاریخ نمایه سازی: 13 دی 1400
Abstract:
Population structure of three kilka fishes (Clupeonella spp.), particularly anchovy kilka (C. engrauliformis), in Iranian waters of the Caspian Sea was surveyed in ۲۰۰۳. A total of ۳۲۳۰ biweekly samples were collected from commercially landed kilka at ۳ stations in Mazandaran and Guilan provinces. Catch and effort statistics were obtained from the relevant organization. Results showed a great decline in the commercial kilka catch from ۹۵۰۰۰ tons in ۱۹۹۹ to ۱۵۴۹۷ tons in ۲۰۰۳. The contribution of anchovy kilka to the total kilka fishery also showed a decline from ۷۱% in ۱۹۹۹ to ۵۲.۵% in ۲۰۰۳, while common kilka (C. cultriventris) increased from ۱۳.۷% in ۱۹۹۹ to ۴۸.۹% in ۲۰۰۳. Fork length range of anchovy kilka showed an increase from ۸۹.۲±۱۲mm in ۱۹۹۹ to ۱۰۰.۴±۴.۹mm in ۲۰۰۳. The age composition of anchovy ranged between ۱+ to ۷+ years and the dominant group was ۵+ years old (age group of ۴+ and ۵+ comprised ۸۴.۶% of population). The K value and L∞ calculated ۰.۵۹۸/year and ۱۱۰.۱۳ mm respectively. Natural, fishing and total mortality coefficient was estimated ۰.۶۹, ۰.۳۱ and ۱ per year respectively. The results showed a sex ratio of F: M= ۶۸.۲: ۳۱.۸.
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