APPENDIX 5.

Distribution of Mnemiopsis in the Kazakhstan sector of the Caspian.

L.Khvan, Yu.Kim

To date no large numbers of Mnemiopsis have been discovered in the Caspian territorial waters of Kazakhstan, these waters remain largely under our control. Unfortunately, the only studies we can reference are form the planned fisheries monitoring. The opportunity to carry out meaningful research to determine the levels of distribution only presented itself in second half of 2001.

Scientific Academy of Kazakhstan Research Institute of Fisheries carried out range of researches in August-September 2001 in Northern-Eastern part of Caspian and partially in Middle Caspian; there aim was to determine distribution and concentration of Mnemiopsis Leidyi in territorial water of Kazakhstan Republic. Atyrau Fund of Environment Protection funded the researches.

Due to the absence of special fishing gear, the samples were taken with Jeddy, Caspian type of net (d=50 and 36sm, gas #49).

During the expedition to the shallow waters of the North-Eastern Caspian (maximum depth 4 m, salinity 4-7 0/00) no evidence of any form of jelly type organisms was found in squares 72-76 and 132-135. The presence of jelly formless organisms has rarely been discovered in the deep-see zones (squares 154-157), which have maximum depth 10 m and salinity of about 8 0/00. They have been found both in water column and at bottom layers, on plants, which were rising up during beam-trawl creeping. Attempts to detect separate organisms were unsuccessful. It may probably be animals’ "depression". Depressed jelly type organisms were also discovered in 2000 in the regions of Western and Eastern Kashagan. However, due to the lack of specialists they fixed all jelly type organisms. Since the process of separation became impossible, it has been determined only total volume of studied organisms in the measuring drum during one creeping. Maximum volume did not exceed 22 ml per creeping.

The most possible reason why Mnemiopsis Leidyi is absent in the North-Eastern Caspian shallow zone is explained by turbid water and rapid salinity level fluctuations, due to constant surges.

Besides that, planned fisheries monitoring also included monitoring of presence of jelly type organisms. However, their presence in region was discovered neither in April, nor in July.

An expedition to the Middle Caspian had place in September 2001. Due to the absence of deep-see vessel, the monitoring was carried out near coastal shallow waters within the border of Turkmenistan (N 42⁰- E 50⁰) till Mangystau and Atyrau regions (N 45⁰- E 50⁰). The depth of the explored regions was about 20m, salinity level – 10 0/00. Water clarity was 8m maximum.

Significant number of jelly type organisms was discovered at N 42⁰- E 50⁰ point. Scientists managed to select 11 organisms which size were 2-15mm. The weights of the biggest ones were not more than 0.6g. Total maximal weight of one sample did not exceed 10g.

The rest of the studied squares had larger number of jelly type organisms. It may probably be explained by impossibility to explore deeper sea zones, where, as known from scientific sources, the groups of jelly type organisms are larger.

Unfortunately, due to the bad weather conditions, the number of carried out assays were insufficient.

We tried to inform people via media about appearance of this alien organism in the Caspian and asked to send us the information. Fisheries are mostly concentrated in the shallow waters and sea fisheries are practically absent due to lack of the navy, that is why we still have no any notifications about the presence of large groups of Mnemiopsis in our waters.