Illustration by Sara Nettle
Florida manatees see a more stable future
Even after 25 years of working with manatees, Robert Bonde can still remember his first swim with them.
He broke the surface of the water, sinking down until his head submerged. Everything was quiet. He could hear the squeaky sounds manatees make, which he can approximate with an otherworldly “ee ee.”
“All your senses are alert,” he said. “It’s not what we’re going to experience sitting on the verandah or on a swing outside. It’s just totally different to immerse yourself.”
Manatees have spent decades floating along on the Endangered Species List, steadily increasing in number. The current state of the manatee is, at first glance, a paradox. Manatees just suffered their most deadly year on record. Manatees may be downlisted from endangered to threatened.
The change would acknowledge that the sea cows are not on the brink of extinction. And despite above average death rates over the past five years, manatees have made a resilient comeback.
Both Bonde and his wife, Cathy Beck, are wildlife biologists working on the United States Geological Survey Sirenia Project, which is dedicated to studying manatees. The project’s Manatee Individual Photo-identification System has cataloged snapshots of manatees since 1978 and is used as a representation of the full population to predict survivability. Last year, a high number of manatees didn’t show up. Researchers can’t say for sure — yet — if that means they died or found greener waters for winter.
This year, the monitoring will carry more weight than usual. If the manatees return, they will be one data point closer to downlisting.
For many of the 3,000 animals in the system, each year of photos adds to a scrapbook of births, injuries, recoveries. Researchers initially identify the different manatees by their scar patterns.
“It’s really ironic that . . . we’re looking at their survival by their scars,” Beck said.
Bonde and Beck have spent most of their married life working to save the manatees. They moved to Gainesville in 1978 when the Sirenia Project started. At the time, neither knew much about the animals.
“We starting reading everything there was to know, real quick,” Beck said.
When they arrived in Florida, manatees were precariously close to dying out. No one knew the cause, so there was no solution. The Endangered Species Act, passed in 1973, gave researchers the funding and infrastructure to evaluate the state of the manatee. As they learned about the animals, they were able to institute regulations such boating speed zones. The population steadily grew. Bonde estimates around 6,000 manatees currently live in Florida, compared to around 1,000 in the ‘70s.
But from 2008 until 2012, cold snaps, algal blooms and red tide started chipping away at the population.
Then came 2013. With 830 tallied carcasses, it was the deadliest year on record for the sea cows. And that only accounts for the found bodies. Hundreds of others could have died without the Florida Fish and Wildlife Conservation Commission recovering them.
The isolated numbers may look bleak, but the bigger question is if the birth rate is outpacing mortality. And Bonde is optimistic.
“From what I’ve seen in every model we’ve predicted and hind-casted back, manatees have outperformed what we’ve given them credit for,” he said.
Manatees have superpowered immune systems. Their boat propeller scars are reminders of encounters that could have been fatal, but weren’t. A manatee can completely repair a wound that cuts down to the muscle in a year. It can lose a rib, heal the tissue over the deep gash and keep on swimming.
So just as the scars are proof of the manatee’s ability to survive, the fact that the species even approached extinction is a sombering indicator of the damage humans can wreck.
As the manatees survive and thrive in Florida, they compete for the same resources. They chow down on seagrass for eight hours a day, and the vegetation supply can’t increase with the population.
“I don’t think the last manatee is going to die because we’re going to hit it by a boat,” Bonde said. “It would die because maybe the boat stirred up the water around the sea grass and the sea grass died.”
Climate change will also play a large role in the manatee’s future. A shift in temperature could lower the salinity of the water and slow the growth of the seagrass. The water quality of the springs could decline. A shift in the delicate environmental balance could violently disrupt the manatee population.
“With a little bit of effort and sacrifice on our parts, we protect manatees and have them around,” Bonde said. “They will reward us with that. So why drive them to extinction? Let your children see the manatees. Let them enjoy the manatees and learn from them. I think we can all learn something from the passive, docile, friendly, intelligent creature who is the size of an elephant who lives in your backyard.”