Fishery biological characteristics and changes in the annual biomass of bigeye kilka (Clupeonella grimmi) in the Caspian Sea


Citation

H. Fazli, . and Zhang C. I., . and Hay D. E., . and Lee C. W., . Fishery biological characteristics and changes in the annual biomass of bigeye kilka (Clupeonella grimmi) in the Caspian Sea. pp. 943-960. ISSN 0116-6514

Abstract

Through most of the last century three endemic kilka species supported the major commercial species in the Caspian Sea. Recent changes in the Caspian Sea ecosystem have occurred as a consequence of climate change and ecological change caused by the invasive ctenophore Mnemiopsis leidyi. We examined the impact of these changes on the population biology of bigeye kilka (Clupeonella grimmi) in Iranian waters of the Caspian Sea from 1995 to 2001. The overall sex ratio (male:female) was 1.65:1. The length-weight regression was 851.2 W 00922.0 L (females) and 907.2 W 008021.0 L (males) indicating a negative growth for both sexes. Growth parameters were estimated as L 142 mm K 0.28 yr-1 t0 -1.39 yr. The instantaneous coefficient of natural mortality was estimated as 0.460 yr-1 and the instantaneous coefficient of fishing mortality varied between 0.469 to 0.980 yr-1. Biomass of the bigeye kilka increased from about 36 900 mt in 1995 to more than 53 500 mt in 1998 but declined to less than 5 900 mt in 2001. This decrease in bigeye kilka was simultaneous with a sharp reduction in anchovy kilka due to the combined effects of fishing and changes in zooplankton abundance and composition soon after the appearance of Mnemiopsis leidyi in the Caspian Sea.


Download File

Full text available from:

Abstract

Through most of the last century three endemic kilka species supported the major commercial species in the Caspian Sea. Recent changes in the Caspian Sea ecosystem have occurred as a consequence of climate change and ecological change caused by the invasive ctenophore Mnemiopsis leidyi. We examined the impact of these changes on the population biology of bigeye kilka (Clupeonella grimmi) in Iranian waters of the Caspian Sea from 1995 to 2001. The overall sex ratio (male:female) was 1.65:1. The length-weight regression was 851.2 W 00922.0 L (females) and 907.2 W 008021.0 L (males) indicating a negative growth for both sexes. Growth parameters were estimated as L 142 mm K 0.28 yr-1 t0 -1.39 yr. The instantaneous coefficient of natural mortality was estimated as 0.460 yr-1 and the instantaneous coefficient of fishing mortality varied between 0.469 to 0.980 yr-1. Biomass of the bigeye kilka increased from about 36 900 mt in 1995 to more than 53 500 mt in 1998 but declined to less than 5 900 mt in 2001. This decrease in bigeye kilka was simultaneous with a sharp reduction in anchovy kilka due to the combined effects of fishing and changes in zooplankton abundance and composition soon after the appearance of Mnemiopsis leidyi in the Caspian Sea.

Additional Metadata

[error in script]
Item Type: Article
AGROVOC Term: Clupeonella grimmi
AGROVOC Term: Mnemiopsis leidyi
AGROVOC Term: Fishes
AGROVOC Term: Aquatic animals
AGROVOC Term: Aquatic organisms
AGROVOC Term: Climate
AGROVOC Term: Climate change
AGROVOC Term: Ecology
AGROVOC Term: Ecosystems
AGROVOC Term: Mortality
Depositing User: Mr. AFANDI ABDUL MALEK
Last Modified: 24 Apr 2025 00:53
URI: http://webagris.upm.edu.my/id/eprint/7842

Actions (login required)

View Item View Item