WSP08457 - Laserfiche WebLink

Home Browse Search

4 2684 marked fish, All fish captured during this p~riod were measured to the nearest millimeter (mm) total length (TL), weighed to the nearest gram (g), marked with a numbered Carlin dangler tag, and released, The 12 fish captured in March and April were anesthesized with a solution of unbuffered MS222, and surgically instrumented with radiotransmitters. The surgical procedure used was similar to the one discussed in Bidgood (1980) and used by Tyus et al, (1981), Lateral incisions, approximately 1.5 centimeters (cm) in length, were made anterior, and dorsal to the insertion of the pelvic fins and closed with 3 to 4 individual sutures, The suture material used was non-absorbable, black monofilament nylon attached to an FS-I cutting needle. Following surgery each implanted fish was also marked beneath the dorsal fin with a numbered Carlin dangler tag, The fish were then held in a flow through live car until they had recovered from the anesthetic and then released, The transmitters were approximately 4,3 cm in length, I,B em in diameter and weighed ll,8 to 12.3 g in the air. The operating frequency was in the 30 MHz band, The transmitters were powered with Lithium cells and had an expected life of 270 days, Eleven of the transmitters were temperature sensitive. Temperature data were transmitted as a function of transmitter pulse frequency, Calibration points of temperature, 0 to 40oC, and transmitter pulse frequency were used to derive regression equations for temperature versus pulse frequency for each unit, The pulse frequency data collected in the field were then used in the equations to obtain temperature, The high, low and mean temperatures of the fish and water temperature of their habitat were plotted for each fish,