Inserting an Acoustic Telemetry Tag into a Lake Trout, Lake Superior

Biologist Mike Lowe, USGS, is surgically inserting an acoustic telemetry tag into a lake trout in Lake Superior. These tags emit a 'ping' which can be heard with a sensistive hydrophone that tells the scientist the location of the fish so their movements can be tracked, in this case, to help us understand spawning behaviour. This photo was taken prior to the COVID-19 pandemic