Mills-Parker, K., J. K. Gaydos, M. Ziccardi, C. Fiorello, D. Mulcahy, E. Whitmer, L. I. Vilchis, and S. De La Cruz. 2012. Post-release monitoring of Western Grebes using implanted satellite transmitters. 39th Meeting of the Pacific Seabird Group, Turtle Bay, HI, February 2012.
Type: Technical report or proceeding
Link: Not available. Please email us at seadoc -@- seadocsociety.org to request a copy of the paper.
Western grebes are in decline along the western coast of the United States and often are impacted by oil spills and natural seeps when wintering along the Pacific coast. There is a dearth of information regarding the efficacy of post-oil spill rehabilitation and the evaluation of rehabilitated grebes post-release has been prevented by a lack of suitable tracking capability. This study was designed to answer several questions including: 1) can satellite transmitters be implanted successfully in Western grebes, 2) how long do the grebes survive post-release, and 3) what are their wintering and migrating patterns? Previous work resulted in a modified surgical technique to implant this species with satellite transmitters. In this next phase of the research, we used this modified technique to implant satellite transmitters in 10 Western Grebes captured in early December 2010 in San Francisco Bay, California. Nine of ten birds survived surgery and were released. Post-release, all birds survived at least 25 days suggesting a lack of complications related to surgery. After 25 days, survival showed a steady decline and currently only two grebes are still transmitting. One bird did not migrate, while the other migrated to Upper Klamath Lake in Oregon in July and recently returned to San Francisco Bay in November 2011. This is the first study to document winter site fidelity and migration of a Western grebe from its marine wintering ground to an inland breeding colony and back. It provides the first step for developing a safe technique for using intracoelomic satellite transmitters for post-oil spill tracking of Western grebes.