Paddlefish Polyodon spathula were tagged with 1.25-mm-long coded wire tags (CWTs) to determine rate of tag loss and identify a suitable tagging location. Tag loss was 77% for paddlefish held 51 d in rectangular fiberglass tanks (tank study), and 3% for fish held 96 d in ponds (pond study). We believe the difference in tag loss between the two studies was related to fish behavior. In intensive culture operations, a paddlefish tends to injure the tip of its rostrum by striking i1 against the walls of the tank; thus, it is likely that high tag loss is a result of rostra being continually scraped. Mortality rate of tagged fish in tanks was 4% and not influenced by tagging procedures. In the pond study, paddlefish with tags implanted 5 mm into the distal end of the rostrum, slightly off the center axis, had significantly lower tag loss (0%) than those implanted 2 mm into the center of the ventral side (3%) or 2 mm into the distal end, slightly off the central axis, (3%). However, we recommend implanting CWTs 2 mm deep into the tip of the rostrum, slightly off the central axis, to allow biologists and anglers to remove a small portion of the rostrum containing the tag and return the fish to the water relatively unharmed.