Telemetry on Wild Sea Lions: Surgeries

surgeryLHX1 tags are relatively small compared the size of a Steller sea lion. Each tag accounts for less than 0.1% (one tenth of one percent) of the typical mass (weight) of a one year old sea lion. This is substantially less than the recommended limit of 3% of an animal’s mass. Using full gas anesthesia and many of the same aseptic procedures as for human surgeries, a marine mammal veterinarian surgically implants two sterilized tags inside the body cavity of the sea lion near the abdomen. The tags are specially coated with an inert material used in some human biomedical implants that prevents body tissue from growing around and sticking to it. This is important, since the coating allows the tag to freely move around the abdomen and come out of the body easily if a predator dismembers an animal. Each sea lion gets two tags to maximize the likelihood that the scientists will receive data if the animal dies (see the LHX Tags page for more information). The first 15 animals that received LHX implants in 2005 through 2008 were monitored for four to eight weeks after surgery to monitor healing of the incision as well as their general health and well being. Results from this initial monitoring showed that normal wound healing is completed within 6 weeks or less and that the surgery is well tolerated. Now animals are monitored for only 1-2 weeks before receiving a final checkup and being released back into the wild.