Pollock Conservation Cooperative Research Center
2000 Awarded Research Projects
Validating the use of satellite-linked mortality transmitters in rehabilitated California sea lions and juvenile Steller sea lions
Award: $60,460
Estimated Completion: February 28, 2003
Abstract
This project addresses the recovery of the Steller sea lion research priority in the PCCRC solicitation. The proposed work represents a significant and vital enhancement of an already funded project: "Determining Survival and Long-term Foraging Behavior of Juvenile Steller Sea Lions through Implanted, Satellite Mortality Transmitters" (funded by a North Pacific Marine Research Program grant to M. Horning). In connection with the already funded project, the proposed work will contribute to testing the leading causal hypothesis for the decline (or failure of the population to recover), as well as to the analysis of seasonality in Steller sea lion dive efforts, mortality, and the relationship of these parameters to fishing activity.
Hence, we propose to implant dual redundant Satellite-linked Mortality Transmitters (SMXs) into ten rehabilitated California sea lions at the Marine Mammal Center in Sausalito, CA. In a second step, we propose to implant dual SMX devices into six transient juvenile Steller sea lions, captured and temporarily held in the Alaska Sea Life Center under a separate project. All sixteen implanted animals will be released into the wild after observation periods ranging from two to eight weeks. After their release, the SMX devices will be monitored through service ARGOS for up to five years.
The primary objectives of the proposed work are:
1. the refinement of surgical procedures for intraperitoneal implantation of SMX devices into California sea lions and Steller sea lions, based on procedure that were developed at the recent Steller Sea Lion Implant Workshop;
2. the validation of the absence of post-surgical complications resulting from the implantation procedures, at first on rehabilitative California sea lions, and then on transient Steller sea lions;
3. the validation of the concept of delayed transmission, implanted mortality transmitters for post-release survival monitoring of free-ranging sea lions.
In addition, we expect to:
4. provide an initial estimate of the failure rate of SMX devices, based on the implantation of the dual redundant SMX unit into ten rehabilitated California sea lions, and six juvenile transient Steller sea lions; and
5. contribute to the validation of a new experimental paradigm in the study of marine endotherms by relating body condition, indicators of health and immunocompetence determined prior to release, to individual survival.
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