Resumen de The use of cardiac monitoring in the assessment of mercury toxicity in the subtropical pebble crab "Gaetice depressus" (Brachyura: Grapsidae: Varuninae)
A. Aagaard, B. Styrishave, Clifford Warman, M.H. Depledge
Heart rates were monitored in the pebble crab, Gaetice depressus using a non-invasive, computer aided cardiac monitoring system. A high degree of intra- and interindividual variability was observed, as was the presence of endogenous circatidal and circadian rhythms. Both acute and sublethal toxicities of mercury were determined. LC50's (96) for mercury were between 0.16-0.20 mg l-1. Exposure to HgCl2 above LC50 (96) (0.3 mg Hg l-1) resulted in rapid and statictically significant increases in heart rate whereas exposure to a concentration lower than LC50 (96) (0.1 mg Hg l-1) resulted in progressive reduction in heart rate similar to that of control crabs.
