REMOTE MONITORING OF HEART-RATE AS A MEASURE OF RECOVERY IN ANGLED ATLANTIC SALMON, SALMO-SALAR (L.)

The introduction of 'Catch and Release' fishery programs are now widel y employed by fisheries managers in most Atlantic Provinces, primarily due to the recent decline of Atlantic salmon stocks on the east coast of Canada. However, there is still considerable debate among special interest groups and regulators as to the effectiveness of the techniqu e. Heart rate telemetry has been utilized as a tool for the assessment of metabolic rate in wild fish by a number of investigators, and was employed in the present study in order to assess recovery following st aged angling events in Atlantic salmon. Wild Atlantic salmon were succ essfully angled at 20 +/- 2 degrees C and 16.5 +/- 1 degrees C at Noel Paul's Brook, Newfoundland. In addition, hatchery reared Atlantic sal mon were angled at the Ontario Ministry of Agriculture and Fisheries R esearch Station, Alma, Ontario, at a temperature of 8 +/- 1 degrees C. Survival rate for the angled salmon was 20% at 20 +/- 2 degrees C; 10 0% at 16.5 +/- 1 degrees C; and 100% at 8 +/- 1 degrees C. Mean restin g heart rate for the fish angled at 16.5 degrees C and 20 degrees C wa s approximately 1.6 and 1.8 times greater than that of fish angled at 8 degrees C. Heart rate, post angling, was found to increase 1.2 fold in the 8 degrees C group, 1.3 fold in the 16.5 degrees C group and app roximately 1.15 fold in the 20 degrees C group. Time to recovery was a ssessed asa return to observed resting heart rate for each individual fish and was found to be similar for both the 8 degrees C and 16.5 deg rees C angled groups (approximately 16 h). Although heart rate telemet ry in fish is, perhaps, not an ideal measure of metabolic rate, the pr esent study has demonstrated that remote monitoring of heart rate is a good indicator of post exercise physiological activity.