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12 Things You Might Not Have Known About Manatees

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In August 2015, the U.S. Fish and Wildlife Service temporarily closed Three Sisters Springs in the Crystal River after more than 300 manatees rapidly moved into the springs. “We have a record number this year,” Laura Ruettiman, an environmental education guide at the Springs, told USA TODAY. “We have 150 more manatees here than have ever been recorded in the past.” Here are a few things you might not have known about these cute, cuddly aquatic mammals.

1. "Manatee" comes from the Carab word manti, meaning “breast, udder.” These docile creatures are also called sea cows.

2. Manatees live in coastal waters and rivers, and they’re the ocean’s largest herbivores: An adult can grow up to 13 feet long and weigh as much as 1300 pounds—and consume 10 to 15 percent of its body weight in vegetation each day.

3. Using their powerful tails, manatees can swim for short bursts at 15 mph. However, the placid animals are usually content to cruise along at 5 mph.

4. There are three species of manatee: West Indian (Trichechus manatus), West African (Trichechus senegalensis), and Amazonian (Trichechus inunguis). The aquatic mammals belong to the order Sirenia, which also includes the dugong (Dugong dugon) and the Steller's sea cow, which went extinct in 1768 due to overhunting.

5. According to a ship log dated January 9, 1493, Christopher Columbus himself said that on the previous day 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.” Columbus wasn’t the only sailor to spot mermaids in the water. The reason they weren’t as beautiful as he might have imagined is because they were actually manatees.

6. Though they can hold their breath while submerged for 15 to 20 minutes, manatees usually surface every three to five minutes to breathe. With a single breath, manatees can replace 90 percent of the air in their lungs; humans, by comparison, replace just 10 percent.

7. Remember when that lady rode a manatee in Florida a few years ago and got arrested? That’s because West Indian manatees are protected by the Manatee Sanctuary Act, which states that it’s against the law for “any person at any time, by any means, or in any manner intentionally or negligently to annoy, molest, harass, or disturb or attempt to molest, harass, or disturb” the endangered animals.

8. Manatees are closely related to two land mammals: the hyrax and the elephant. While most animals have a heart that has a point, elephants and manatees have hearts that are rounded on the bottom.

9. The endangered animals are threatened by a number of things, including toxic red tide and run-ins with watercraft. According to Florida Today, 361 of Florida’s West Indian manatees died in 2014; 19 percent of the overall death toll came from watercraft.

10. Manatees have 2000 thick, whisker-like hairs called vibrissae on their faces, and 3000 on their bodies. These innervated follicles help the manatee sense and explore the world around it.

11. The manatee has a smooth brain, and the smallest brain of all mammals in relation to its body mass. But that doesn’t mean they’re stupid: According to a 2006 New York Times article on the work of Roger L. Reep, a neuroscientist at the University of Florida at Gainesville, manatees are “as adept at experimental tasks as dolphins, though they are slower-moving and, having no taste for fish, more difficult to motivate.”

12. Manatees are nearsighted and can see in blue, green, and gray—but not red!

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Whale Sharks Can Live for More Than a Century, Study Finds
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Some whale sharks alive today have been swimming around since the Gilded Age. The animals—the largest fish in the ocean—can live as long as 130 years, according to a new study in the journal Marine and Freshwater Research. To give you an idea of how long that is, in 1888, Grover Cleveland was finishing up his first presidential term, Thomas Edison had just started selling his first light bulbs, and the U.S. only had 38 states.

To determine whale sharks' longevity, researchers from the Nova Southeastern University in Florida and the Maldives Whale Shark Research Program tracked male sharks around South Ari Atoll in the Maldives over the course of 10 years, calculating their sizes as they came back to the area over and over again. The scientists identified sharks that returned to the atoll every few years by their distinctive spot patterns, estimating their body lengths with lasers, tape, and visually to try to get the most accurate idea of their sizes.

Using these measurements and data on whale shark growth patterns, the researchers were able to determine that male whale sharks tend to reach maturity around 25 years old and live until they’re about 130 years old. During those decades, they reach an average length of 61.7 feet—about as long as a bowling lane.

While whale sharks are known as gentle giants, they’re difficult to study, and scientists still don’t know a ton about them. They’re considered endangered, making any information we can gather about them important. And this is the first time scientists have been able to accurately measure live, swimming whale sharks.

“Up to now, such aging and growth research has required obtaining vertebrae from dead whale sharks and counting growth rings, analogous to counting tree rings, to determine age,” first author Cameron Perry said in a press statement. ”Our work shows that we can obtain age and growth information without relying on dead sharks captured in fisheries. That is a big deal.”

Though whale sharks appear to be quite long-lived, their lifespan is short compared to the Greenland shark's—in 2016, researchers reported they may live for 400 years. 

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Animal Welfare Groups Are Building a Database of Every Cat in Washington, D.C.
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There are a lot of cats in Washington, D.C. They live in parks, backyards, side streets, and people's homes. Exactly how many there are is the question a new conservation project wants to answer. DC Cat Count, a collaboration between Humane Rescue Alliance, the Humane Society, PetSmart Charities, and the Smithsonian Conservation Biology Institute, aims to tally every cat in the city—even house pets, The New York Times reports.

Cities tend to support thriving feral cat populations, and that's a problem for animal conservationists. If a feline is born and grows up without human contact, it will never be a suitable house cat. The only options animal control officials have are to euthanize strays or trap and sterilize them, and release them back where they were found. If neither action is taken, it's the smaller animals that belong in the wild who suffer. Cats are invasive predators, and each year they kill billions of birds in the U.S. alone.

Before animal welfare experts and wildlife scientists can tackle this problem, they need to understand how big it is. Over the next three years, DC Cat Count will use various methods to track D.C.'s cats and build a feline database for the city. Sixty outdoor camera traps will capture images of passing cats, relying on infrared technology to sense them most of the time.

Citizens are being asked to help as well. An app is currently being developed that will allow users to snap photos of any cats they see, including their own pets. The team also plans to study the different ways these cats interact with their environments, like how much time pets spend indoors versus outdoors, for example. The initiative has a $1.5 million budget to spend on collecting data.

By the end of the project, the team hopes to have the tools both conservationists and animal welfare groups need to better control the local cat population.

Lisa LaFontaine, president and CEO of the Humane Rescue Alliance, said in a statement, “The reality is that those in the fields of welfare, ecology, conservation, and sheltering have a common long-term goal of fewer free-roaming cats on the landscape. This joint effort will provide scientific management programs to help achieve that goal, locally and nationally."

[h/t The New York Times]

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