SCIENTIFIC REVIEW OF FISH MORTALITY CASE ON FISH CAGE AND FISH NET AT FOUR VILLAGES OF MARTAPURA RIVER BANJAR  REGENCY

Mass fish mortality case that heppened at Martapura river of Banjar Residence Province of South Kalimantan hapenned at two subdistrict, Astambul subdistrict village of Pingaran Ulu, and Karang Intan Subdistrict Village of Loktangga, Mali-mali and Sungai Arpat starting on Friday October 6th 2012. Sign of the beginning of  this case is mortality from a few of fish and continue to Sunday October 28th 2012 with many more died fish that almost fully on fish cage and fish net.

Fish species that was died is an aquacultre fish type like belly fish, Carp and tilapa, whereas the wild fish that was died is Catfish, wild carp, eels and swollen fish with range of  each weight 250-350 gr/fish. Total of died fish is more than 2 billion with total weights are ± 4.600 Kg.

Fish mortality pattern is acute with clinical signs is weaks breathing om water surface, starts from adult fishes and follows by smaller until fries, shown that fish are weak and not responsif  with the shock, if looking at the gills shows hiperemi. The fish that shows weakness cut open and observed. Visceral organs shows normal. With the histology method for visceral organs shows hyperlasia and sekunder lamelle fusion, oedema and or hyperthropi on primer lamelle until missing of many of sekunder lamelle. Liver shows congestion on capillary and sinusoid, whereas spleen shows vacuole.

To complete the data concerned with fish mortality, water was taken to laboratory analized and also checking at that time. Result of that test are generally DO : < 3 mg/l and ammonia > 0,02 mg/l.

From sampling spot Sungai Arpat village, subdistrict of Karang Intan DO 1,4  mg/l, BOD 32,3 mg/l, ammonia 0,85mg/l, Fe 0,46 mg/l, Zn 0,07 mg/l, Chloride 7,5 mg/l, Phosphat 3,93 mg/l dan Sulfide 0,9200 mg/l. Sampling spot Pingaran Ilir Village Subdistrict of Astambul BOD 8,4 mg/l, ammonia 2,94 mg/l, Fe 0,21 mg/l, Mn 0,2 mg/l, Zn 0,06 mg/l, Chloride 4,9 mg/l, Phosphate 1,89 mg/l, Sulfate 4,7 mg/l, Sulfide 0,7271 mg/l dan Flouride 0,79 mg/l, whereas on sampling spot Pingaran Hulu village Subdistrict of Astambul shows BOD 7,7 mg/l, ammonia 2,27 mg/l, Fe 0,35 mg/l, Zn 0,08 mg/l, Chloride 6,0 mg/l, Phosphate 1,2 mg/l, Sulfate 4,6 mg/l, dan sulfide 0,1768 mg/l.

From test that had done concluded that cause of mass fish mortality is from the environment or  water quality in this case is low is Dissolved Oxygen,  high of ammonia concentration and also other causes from the water.