Like many people, I’m very fond of manatees. Despite being mossy and a little bit potato-like, there’s something incredibly engaging about them. And, like many people, I’ve also spent a lot of time teleworking over the last few months. Fortunately, the first situation has made the second a little easier. At noon, several days a week, I spend time watching manatees having lunch in real time at Homosassa Springs Wildlife State Park, Florida. They’re fed lettuce (iceberg, I think) and their meal is live-streamed on the Explore website.
Most of the time, if you don’t watch at noon, you’re more likely to see schools of fish crevalle jack, black-striped mullet and others, meandering slowly through the seagrass. That’s a tranquil scene in itself but seeing a manatee come up in front of the camera is like watching the moon rise at close range, its back textured with forest of algae and scars.
Watching them eat is pretty amazing too. They sort of attach to a head of lettuce munch on it until its gone. It led me to wonder how they manage it. Those fins aren’t quite long enough reach their mouths effectively, so they can’t hold their food in place. How do they manage it? The answer lies in their complicated, muscular mouth structure. Relatives of the elephant, they have a also have a prehensile upper lip that it uses to pull food into their mouth. Each side of the lip can move independently of the other. Behind the lips, horn-liked ridged pads break food down to smaller pieces. Manatees are one few mammals that keep replacing their teeth their entire lives. They have four sets of six to eight “marching” molars that fall out as they wear down. New molars then move in behind them.
So that’s one lunchtime mystery solved. It’s hard, though, to think about manatees very much and not think about their conservation. “Save the Manatee,” an organization devoted to maintaining sirenian species lists a the major causes of mortality. Topping a list that includes monofilament line, fishing nets, fishing hooks, litter, poaching is collision with watercraft. It’s easy to miss them in the water, especially in a low boat traveling at speed. Many manatees, and their cousins the dugongs, Awareness is vital in this and Save the Manatee does an important job.
One thing they don’t mention specifically is anthropogenic climate change. According to Blown Away, a 2019 report by Dr. Shaye Wolf of the Center for Biological Diversity, the manatee is on a list of ten species that are especially vulnerable to the huge storms that wrack Florida, and which are on the increase. They say that increased storm intensity, rainfall and storm surge cause considerable issues for manatees:
Long-term studies have found that adult manatee survival drops significantly after strong hurricanes. Although they tend to hunker down in sheltered waters during storms, hurricane storm surge can push manatees out to sea, injure them with debris and destroy the seagrass beds that they rely on for food. They can also get stranded when the high waters recede, and manatees have ended up in drainage ditches, roads and people’s backyards. In 2016 Hurricane Hermine left seven manatees stranded in a golf-course pond, while a mother and her calf were discovered a mile inland in a mud puddle in the forest. (Page 6.)