1) A lot of plants and factories contaminate the Caspian Sea, thats why all of the alive organisms are dying
2) Alco people waste water in the Caspian Sea for their own problems, for example, car washing, drinking, etc.
3) After this, from Caspian Sea people take a lot of oil, and tankers, that transport oil can be broken, and all of oil will fill to the sea.
4) Most of the fishes in this sea died because of poaching.
5) Most of the fishes in the Caspian Sea ill, because in the sea live one bactery, which can be cause of the illness