U.S. Geological Survey Manatee Captures and Health Assessments

Back in December, NMLC Animal Care Staff was privileged to have to opportunity to assist the U.S. Geological Survey with their winter manatee captures and health assessments in Crystal River, Florida. The U.S. Geological Survey has been running a manatee health assessment program in Crystal River since 2006, with assessments performed a couple times throughout the months of December through February.

Our team participated in a two-team capture approach, examinations, and release to add to sample and data archives of West Indian manatees at the Crystal River National Wildlife Refuge to determine the fitness related to environmental and medical issues.

Roughly 150 volunteers formed a team of experienced biologists, veterinarians and technicians from around the world. One team set up the medical tents on a thin, muddy stretch of beach, while another team gathered around the bend where they prepared to corral and capture the manatees for assessments. The last team was anchored on the top of a bridge to scout for animals. Once an animal was spotted, the boat team spread a green net in a semicircle from shore to shore, enclosing the manatee from swimming away.

Land based volunteers reeled in the net as the manatee emerged from the water, repeatedly slapping the ground with it’s powerful tail. The animal was removed from the net, and restrained to calm the animal before stretching the manatee to be loaded onto the boat and brought over to the medical tent.

Immediately after the manatee was pulled from the water, vital signs were monitored. Sea cows have the heaviest of any mammal bones. These critters are not meant to be on land, but when they do, manatees only have about 50% lung capacity due to the pressure of being out of water. To maintain breathing, every minute a bucket of water was poured over their heads to stimulate breathing as if they were in the water. A CO2 reading was recorded during every exhale and oxygen was given during each inhale.

Once the animal was in the medical tent, sheltered from the sun, a Frisbee was places under the body to collect a urine sample. Skin and blood samples were collected for analysis. A tiny incision was made in the skin of both shoulders to insert a pit tag, just
like the microchips that are placed in our pets. Measurements including girths were also recorded. The manatee was then stretched to the weighing arch, where the animal was levitated off the ground by a small crane to collect a weight.

2015 was a special year; it was the first time all females were ultrasound to monitor pregnancies. Sure enough, one of the last females was 4-5 months pregnant. Everyone gathered around the monitor to watch the fetus move around inside its mothers belly.

Animals were then put back on the boat, where a small chunk of tail was removed for genetic testing. The boat then would drive to deeper water, where the animal was then released.

THANK YOU U.S. Geological Survey for allowing our team to take part in such important marine mammal field research!!!