THE STUDY OF THE TOXIC EFFECTS OF MERCURY-II-CHLORIDE TO CHUB Leuciscus cephalus (L., 1758)

ABSTRACT Mercury is one of the most harmful heavy metals, present in many aquatic media. This study was aimed to determine the acute toxicity of   mercury-II-chloride and behavioral changes in    Leuciscus cephalus insert ignore into journalissuearticles values(L., 1758);. Leuciscus cephalus were selected for the bioassays experiments and caught in Kirmir branch of Sakarya river. Behavioral changes at each mercury-II-chloride concentration were recorded. The experiments were repeated 3 times. Water temperature was regulated at 22±1 o C. The 96-h LC 50 value of mercury-II-chloride insert ignore into journalissuearticles values(HgCl 2 .H 2 O); on Leuciscus cephalus was found to be 0.55 mg/L insert ignore into journalissuearticles values(0.53-0.57); according to Probit Analysis. There were significant changes observed in the behavior of the fish as the concentration of the toxic compound increased.   Key Words: Leuciscus cephalus; Mercury-II-chloride; Lethal concentration; Bioassay