Fishery and biological aspects of anchovy Kilka ( Clupeonella engrauliformis) in the southern Caspian Sea



  This paper aimed to investigate
the fishery and biological characteristics of anchovy Kilka in Iranian waters
of the Caspian Sea from 2005-2007, including length and age structure ,Von Bertalanffy growth parameters, length and age at
first capture, condition factor, sex ratio,
natural and fishing mortality. The examination of
catch data approved that Kilka population in the Caspian Sea have been declined
a few years ago following entrance jellyfish Ctenophora Mnemiopsis leidyi.
The greatest destruction of anchovy kilka catch was occurred while the catch of
anchovy from 4250 tonnes in 2005 reached to 924 tonnes in 2007.
The results showed that K value and L∞ calculated 0.375/year,
131.7mm, respectively. The instantaneous coefficient of natural mortality was
estimated 0.49/year.The instantaneous coefficient of fishing mortality and total mortality was 0.51 /year and 1/year, respectively. The
Exploitation rate was calculated as 0.51. The length and age ranges restricted comparison
to last decade and sharply decreased recruitment. In
the past few years, the main reasons of
disintegrates among anchovy Kilka stocks in the Caspian
Sea were synchronized
overfishing competitive anchovy Kilka with M. leidyi.