Declining Production of Cockles in Relation to Ammonia Concentrations in Sungai Buloh River, Selangor

Abstract

This research was conducted in Kampung Bagan, Sungai Buloh, one of the major areas for cockles farming in Selangor. Based on the Fisheries Annual Statistic Report 2000, issued by the Department of Fisheries Malaysia, the total production of cockle landings in Selangor was 6,922 mt utilizing 654 ha farming area with a production rate of 11 mt/ha. Meanwhile, in the 2011 report, the total production of cockle landings had increased remarkably to 26,505 mt with further expansion of 5,593 ha of cockle farming area. It shows an increasing number of productions and area of cockle’s farming. However, the production rates for 2011 had declined to 4.7 mt/ha. The declining of cockle’s production rate was due to several factors. One of the factors is high ammonia concentration in the water. To test this hypothesis, several water samples were collected from the site to test the ammonia concentration in the water by using the colorimeter base on Salicylate method. From these tests, the readings for ammonia concentration in the farm area ranged from 0.3 mg/L up to 4 mg/L. This indicates that ammonia concentration had exceeded the cockle maximum tolerance level towards ammonia. Thus, high ammonia concentration is one of the factors that cause cockles mortality resulting in declining of cockle production in Selangor.

Keywords: Cockles, Ammonia concentration, production rate