9th January: Manatees

On this date in 1493 Christopher Columbus reported in his log his first sighting of manatees. Here are ten fascinating facts about these creatures.

1. Christopher Columbus reported in his ship's log on this date that he “distinctly saw three mermaids, which rose well out of the sea; but they are not so beautiful as they are said to be, for their faces had some masculine traits.” This is because he was looking at manatees, not mermaids.
2. Manatees are placid, usually slow moving aquatic mammals (usually swim at 5 to 8 kilometres per hour (3 to 5 mph), but can manage up to 30 kilometres per hour (20 mph) in short bursts) sometimes known as sea cows.
3. They belong to the family Trichechidae, which consists of three species: the Amazonian manatee (Trichechus inunguis), the West Indian manatee (Trichechus manatus), and the West African manatee (Trichechus senegalensis). The African and Amazonian species are shy and secretive, so most of what we know about these animals relates to the West Indian variety which migrate to the coast of the US and are frequently found in Florida.
4. They have been spotted as far north as Cape Cod and New York, but this is rare because they don't like the cold. They cannot survive below 15 °C (60 °F), and will suffer stress in temperatures of less than 60 degrees F. Despite their rotund appearance they are not that well insulated. Most of their bulk is made up of their digestive system. In winter they seek out warm springs and even power plant output areas.
5. The closest living relative of the manatees are Elephants and hyraxes.
6. They differ from most mammals in several ways. Most mammals have seven neck vertebrae. Manatees and tree Sloths are the only mammals which have just six. Manatees also replace their teeth throughout their lifetime, and the only other mammals with this characteristic are elephants and Kangaroos.
7. The manatee has a smooth brain, and the smallest brain of all mammals in relation to its body mass. They are not stupid, however. Studies have shown they perform as well as Dolphins in discrimination and learning tests and their long term memory is good. They can learn basic tasks, are extremely sensitive to touch and can differentiate colours, although they cannot see the colour red. It's harder to study their intelligence than it is for dolphins, though, partly because they move slower but also, according to scientist Roger L. Reep "because having no taste for fish, they are more difficult to motivate.”
8. Manatees don't have any natural predators other than people. Native Americans made war shields, canoes, and shoes from manatee hides, and they used to eat their meat. They also used their ground up bones to treat asthma and earache. Now endangered, it is illegal to hunt them or even harass them (as Ana Gloria Garcia Gutierrez, of St. Petersburg found to her cost in 2012 when she was arrested after being photographed riding one). The greatest danger to manatees nowadays is boats. Because they move quite slowly and their hearing is in a higher frequency range than might be expected for such a large animal, they don't always hear a larger boat coming. In Florida, people can often identify individual manatees by their propeller scars.
9. In West African folklore, manatees were considered sacred and were thought to have been human. Killing one was taboo and required penance.
10. The oldest manatee in captivity is Snooty, who lives at the South Florida Museum's Parker Manatee Aquarium in Bradenton, Florida. He was born at the Miami Aquarium and Tackle Company and at time of writing is 66 years old.