Survey on some biological aspects of the shrimps of the Caspian Sea in the coastal water of the Golestan province.

This study was conducted from january. 2002 to April .2004. During this survey four research cruises were carried out on aquatic animals. This survey was based on cruise and area which are as follow: 1. Identification of species _ Palaemon adspersus _ Palaemon elegans 2. Length and weight frequencies 3. Length and weight Relationships 4. Distribution according Catch Per Unit Area (CPUA) separately for each sampling station. 5. Sex ratio of P. adspersus 6.Biomass P. adspersus: Following results for p. adspersus was obtained in The Gorgan bay: Min. and Max. of carapace length (CL) in 1st cruise were : 11.50 and 18.40 mm ( female ) 9.60 And 15.70 mm (male) respectively. CL mean was 13.99 ±1.51 and 13.61 ± 1.37 mm for female and male respectively. Min. and Max. of total weight (TW) was 0.7 and 3 gr. (female ), 0.2 and 1.80 gr. (male) which their mean was 1.36 ±0.51 and 1.23±0.32 for female and male and female respectively. Min. and Max. of CL in 2nd cruise were: 8.70 and 18.70mm ( female),8.70 and 15.60mm(male)which the mean were 13.89±2.4 and 11.59±1.62mm for females and males respectively. Min. and Max. of TW in Second cruise were 0.6 and 3.80 gr (female), 0.5 and 2.70 gr (male) which the mean were:2.13±0.7 and 1.22 ±0.43 for females and males respectively. L/W relationship equations were as follow in the 1st and 2nd cruises: 1st cruise: TW = 0.0007CL . .8418, R²= 0.7623, (female) TW=0.0014CL. .5872, R²=5402, (male) 2nd cruise: TW=0.0066 CL. .1847, R²=0.8146, (female) TW= 0.0044 CL. .2859, R²=0.8149, (male) Sex ratio (M/F) in the 1st and 2nd cruises were 1.18:1 and 0.44:1Respectively. Distribution in the 1 st cruise obtained in the East, eastern south near coasts (less than 1 n mile) and in the 2nd cruise obtained in the North east, North and South parts near coasts. In the South east of the Caspian Sea: Min. and Max. CL were 5.6mm (1st cruise) and 17.50mm (3rd and 4th cruises). L/W relationship equations were: TW = 0.0019 CL. .6037, R²=0.7814 (3rd cruise) And TW = O.0023lCL. .5475, R²=0.8804. In general numbers of shrimps were less in the 1st and 2nd cruises. Sex ratio (M/F) obtained 1:1, 1:1, 0.52:1, and 1.02: 1 respectively from 1st to 4th cruises. Shrimps were present in all depths however, when the temperature dropped this species moved toward deep water. P.elegans: CPUA and Biomass were estimated . The biomass was 46.64 Kg and 97.62 Kg in TheGorgan Bay and south east of The Caspian Sea respectively . The number of P.elegans was very few both in the Gorgan Bay and the South east of the Caspian Sea. The review of The P.elegans is described at The very end of the present research report.