Behavioural Responses in Mudskipper (Periopthalmus Papilio) Exposed to Sodium Bromide under Laboratory Conditions

One hundred and eighty (180) mudskipper (Periophthalmus papilio) of equal size (mean length 18.74 ± 2.64cm and mean weight 156.68 ± 1.81g) were exposed to different concentrations (0.0mg/l – control, 5.0, 10.0, 15.0, 20.0 and 25.0mg/l) of sodium bromide a biocide, to determine the Behavioural responses of opercula beat frequency (OBF), tail beat frequency (TBF), 96 hour lethal concentration (96h.LC50 and median lethal time (MLT50). The result obtained indicated that P. papilio showed initial stress responses such as increased opercula ventilator rate, erratic swimming and gasping for air. The pattern of response of TBF to time and concentrations of the biocide was irregular, whereas that of OBF tended to decrease with increase in time, but increased with increase in concentrations. Also cumulative mortality values increased with exposure time and concentrations