Survival of Tagged and Released Atlantic Sailfish (Istiophorus Platypterus: Istiophoridae) Determined with Acoustical Telemetry

During 1974–1976, eight acoustical tracking experiments were conducted along southeast Florida to assess immediate mortality of tagged and released Atlantic sailfish, Istiophorus platypterus. All sailfish were caught by rod and reel, tagged externally with ultrasonic transmitters, and tracked for periods of 2 h 56 min to 28 h 21 min. Condition of each specimen at release was determined by observations of injury, extent of exercise period, and handling. No relationship was noted between size (age) and condition state. Seven sailfish survived. One specimen sustained severe eye injury, bled profusely, and was attacked and killed by a shark 6 h 25 min after release. Twenty minutes appeared sufficient to at least slightly exhaust most sailfish. It is recommended that anglers strive to catch specimens within this time period. The survival of seven sailfish supports the continuance of releasing programs. Effect of tagging mortality on return rates now appears less significant.