As part of a multi-phase study aimed at examining the impact, habitat use, and movement patterns of the invasive rodent the nutria (Myocastor coypus), we developed a methodology to most effectively capture and implant these animals with radiotransmitters. Using a hand-held fishing net, we captured 20 adult nutrias from an airboat and implanted them with intraperitoneal radiotransmitters. We used the anesthetic tiletamine-zolazepam (Telazol®, Ft Dodge Animal Health, Ft. Dodge, Iowa) to immobilize the animals during surgery. We released all individuals back into a fresh water floating marsh habitat within 24 hours of implantation. There was increased survivorship when we placed animals in a predator-free enclosure for a minimum of 3 days. We found that the combination of airboat capture, Telazol® anesthesia, and 24-hr post-surgery release was successful only if animals could be kept in a predator-free environment for at least 72 hours. Therefore, if holding facilities and sufficient temporal, monetary, and human resources are available, these methods may result in sufficient survivorship to allow for the monitoring of these and other medium-sized, semi-aquatic mammals.