Use of oviduct-inserted acoustic transmitters and positional telemetry to estimate timing and location of spawning: a feasibility study in lake trout, Salvelinus namaycush

Table 1 Summary of results from a laboratory study of retention and expulsion of oviduct transmitters in female lake trout

Stage	Inserted	Implanted
Initial sample size (N)	22	22
Retained oviduct transmitter until end of spawning period	18 (82%)	21 (95%)
Became ovulatory (ripened)	17 (94%)	18 (86%)
Percent of ripe trout that expelled transmitter with eggs	15 (88%)	16 (89%)
Percent of total trout that expelled transmitter with eggs	68%	73%

Oviduct transmitters were either ‘inserted’ into the body cavity via the oviduct or ‘implanted’ surgically just anterior to the genital pore. Values are the number of lake trout that reached each stage and percentages in parentheses are based on the number of lake trout that made it to the previous stage.