Use of Acoustic Transmitter-Equipped Remote Sedation to Aid in Entangled Sea Lion Response
- Entanglement
- Ocean trash
Abstract
Free-ranging California sea lions (Zalophus californianus) with marine debris entanglements were darted with a combination of medetomidine, butorphanol, and midazolam by using acoustic transmitter-equipped darts. Of the 15 animals sedated, 13 (87%) reentered the water and were tracked by using a unidirectional hydrophone. Sea lions that entered the water continued to surface and breathe postsedation. There were three mortalities (20%) during the course of this study due to the following: suspected drowning caused by entrapment under a dock, overdose due to inaccurate weight estimation, and trauma caused by a dart puncturing the animal's abdomen. The drug combination, new dart design, and tracking techniques allowed for successful remote sedation and capture of California sea lions in high-risk situations and improved our ability to determine the final outcome for all cases. These methods allow targeting and capture of individual animals, while minimizing disturbance to other animals.
Frankfurter, G., DeRango, E., & Johnson, S. (2016). Use of Acoustic Transmitter-Equipped Remote Sedation to Aid in Tracking and Capture of Entangled California Sea Lions (Zalophus californianus). Journal of Wildlife Diseases, 52(3), 730–733.
ocean trash
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