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Archive for October, 2009

When I heard of biologists using manatees’ many boat scars to tell them apart, I pictured a fast CSI-like computer sorting flippers like fingerprints until, seconds later, MATCH flashed on the screen. Unfortunately, says wildlife biologist Cathy Beck, who runs the program for the U.S. Geological Survey, it’s a lot more slow and still requires a human to make a match. (Cops say the same thing about fingerprint matching, too.)

“Years ago we looked at various software,” she says. “It’s way out of the kind of budget we’d ever get.”

So the Geological Survey mantains a meticulous database of 2,200 known manatees known as the Manatee Photo Identification System (MIPS). Of those 300 are known to be dead. With a U.S. population roughly estimated at about 3,000 to 4,000, that could be half the population. But the facts about manatees and their populations are so uncertain that Beck doesn’t like to speculate.

Instead, she’s trying to make sure everything in the database is certain. So, she only allows in manatees that have at least two distinguishing features. There has to be pictures of each manatee’s tail, back and each side. In theory that could be done with just four pictures, she says “but that’s never happened.” And then the match has to be verified by two humans. Complicating the process, manatees are constantly aquiring new injuries and changing their appearance. “We need to keep up,” Beck says. “A new injury may obliterate an old feature.”

  • At least two distinguishing features
  • Clear pictures of the tail, back and each side
  • Match verified by two humans
  • Wounds have to be healed because they change appearance so much

People may think they’ve seen their favorite manatee, but Beck demands proof: “People are always saying ‘I saw so-and-so,’ but I ask ‘where’s your picture?'”

Complicating matter, she has a number of what she calls “twins,” manatees whose scars are nearly identical. Others, like Ilya, the manatee that recently trekked to Cape Cod and is–we hope–heading on his way down to Florida, ares easy to ID in photos, Beck says. Ilya has a distinctive chunk taken out of his tail and a white scar on his forehead. The head scar is handy for trackers to pick him out when he sticks his head up by docks up and down the East Coast. The fact that he visits docks, however, doesn’t set him apart. Since manatees need to live on the coast, with its mix of salt, brackish and fresh water, they’re naturally around docks. “That’s just what manatees in Florida do,” she says.

Because she only allows complete matches in the system, she has lots of photos that come in that are just sorted by body part, waiting for a match. “We may follow one animal for years and only get its back. We may follow one animal for years and only get its tail,” she says. “And then we find out its the same one.”

Some animals aren’t spotted for a long time. Chessie, the manatee famous for migrating to New England in the 90s, hasn’t been seen since 2001. But, they haven’t found his carcass, either. They once had a manatee that stayed out of pictures for 14 years, then was spotted again. Manatees can live 50 or 60 years, so even the pictures she has of manatees dating back to the ’70s could still be out there.

Some manatees stay out of the database by being clean of scars, while others continually get banged up. Beck has noticed that females are more apt to get entangled in fishing lines around their flippers.

And Beck is hoping to build on the database. The USGS still has thousands of pictures people send in yet to be sorted. And she’d like to track genetics, but already knows the small population is closely related. That will help eventually not only track individuals but help biologists make the population healthy.

Want to See a Manatee in the Wild? Check out this map and list of places.

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The last time anyone saw Ilya the manatee on Sept. 25, he was hanging around the docks of Milford, CT, (the middle of the state’s coast) presumably headed towards New York City and then the warm water he needs in Florida. I got to write a fun story about Ilya for New York Magazine and to talk to a bunch of manatee rescuers, identifiers and caretakers along the way.

Ilya may have already passed New York since Milford is only 60-some miles away. Manatees normally only swim about 3 mph–aside from short burst of up to 20 mph–and they sleep half the day.

If Ilya turns out to be hanging out in New England still, he’s in trouble. The U.S. Fish and Wildlife Service might try to rescue him if he lingers. Last year they tried to save Dennis the manatee from Dennis, MA, by trucking him 27 hours to Florida in the back of a rental truck, surrounded by a heating blanket and medical care. He died, but Nicole Adimey, who runs the USFWS rescue program, says that he was in bad shape to start; they can truck manatees around the country. “They’re pretty resiilent animals, actually,” she says. They would’ve grabbed him sooner if he stayed in one place.  Terry Clen, the Dennis harbor master, says Adimey instructed him to do what is normally forbidden with manatees: give him a hose to keep him happy and in place.

Clen says this year Ilya looked healthier and so Adimey told him to be sure the manatee didn’t get food or drink so he’d keep moving. Clen says the toughest part of New York harbor (aside from the busy boat traffic) will be Hell Gate, the narrow passage to the East River with tough currents.
We only know of a handful of manatees making it through New York harbor. In 1995, biologists were so alarmed to see a manatee as far north as Chesapeake Bay they named him Chessie and flew him home. Tagged, he went up up the next two years, reaching Rhode Island and passing right by the Statue of Liberty, says Cathy Beck, a wildlife biologist who runs the manatee identification program for the USGS.
About every other year since, a manatee spotted north of the Chesapeake and all of the ones they’ve ID’d have been males, Beck says. In 2006, one popped up next to Chelsea Piers, then near the Tappan Zee Bridge in Westchester. Did he miss the turn for Long Island Sound? Maybe–but a manatee did make it to Cape Cod that year. And manatees have been spotted by Montauk, meaning they bypassed Manhattan.
Manatees were spotted in the Chesapeake in the 1800s, Beck says. Did they used to come here before we killed them all? Is global warming letting them push north? Are these just bachelors looking far and wide for a female? Or is Florida getting crowded with manatees because they’ve recovered so much? All of those are going theories, but nobody knows.
Becks, like all manatee scientists, likes to emphasize how little we know about the endangered, enigmatic species everyone loves. We don’t know why they travel or how many there are–or were. We think it’s 4,000 or so and numbers are up. But, Save the Manatee doesn’t want anyone to get too self-congratulatory about manatee recovery.
Becks was surprised when she figured out it was Ilya heading north. She’s seen pictures of him for years–all either around Miami, where he was first sighted with his mom in 1994, or more recently in the Keys. Already a boat propeller had taken a hunk of his tail. Ilya played with another manatee calf named Napolean, so a biologist who was a fan of The Man from Uncle named him Ilya. The next year he took a boat in the forehead, which left him with a white circle there. Those make him easy to identify. Biologists know he’s tried to mate, says Becks. But since male manatees for a mating herd that chases a female, we don’t know if he was successful.

The few manatees that have ventured north have peculiarly stopped at the same towns (Dennis, MA; Port Judith, RI, for example) and in some cases even visited the same storm drains for a freshwater drink.”We’re seeing them at the same places because those are the best places for manatees,” says Becks–not because they’re following a trail. They can detect subtle differences in how warm or salty water is. They need to live close to the shore to eat leaves and stay warm in winter. That means they’re around boat docks in Florida. “It’s not unusual for Ilya to come into a marina,” Becks says. “That’s just what manatees in Florida do.”

We may never know how Ilya’s journey home went. One manatee went 14 years between sightings, Beck says. Or he could pop back up at the dock he drank from in New Jersey. I hope somebody sees him soon and it’s down south.

Want to see manatees? Your best bet is by power plants in Florida in the winter. Check out this map of where to see manatees and other unusual animals.

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Think that smiling dolphin is happy to see you? Think again. If you’re looking at brochures for Florida’s hundreds of dolphin tours, you and the dolphin may be better off if don’t fall for the smiley dolphin tour ads. That familiar pose is really a dolphin begging for food–something wild dolphins shouldn’t do, says Jessica R. Powell, biologist from the National Marine Fisheries Service.

“It’s a very unnatural behavior,” says Powell. “You never see a wild dolphin doing this unless it’s fed or conditioned to people. It’s actually an indication of a number of problems” with how people are treating that dolphin.
That’s why the Fisheries Service voluntary guidelines for tours, Dolphin Smart, bans the begging dolphin grin pictures in ads–along with anything else that gives you the idea you’re going to be hanging out with some wild dolphins that will be thrilled to make your acquaintance. The program’s main thrust is about not disturbing the dolphins. Operators go through training, learning keep respectful 50 yards from dolphins, learn signs that they’re getting annoyed with you (they may “chuff”–a kind of angry dolphin huff–for example) and put their engines in neutral when a dolphin approaches. Plus, they have to teach the public about dolphins.

But teaching tourists dolphin etiquitte is a hard in market where hundreds of tours compete for tourists. Powell recently counted 107 outfits doing tours just on the west coast of Florida from Tampa south. For 66, dolphins are their primary business. The task isn’t made any easier by all the programs to “swim with dolphins.”

What tourists may not realize is that the dolphins in pictures smiling, dancing or hauling adults around are captive and trained. And those interactions greatly stress them, behavioral biologist Toni Frohoff has found. Frohoff, director of research at TerraMar Research and Trans-Species Institute of Learning has found that people overestimate their ability to read dolphins.

“An open jaw display might look like a laugh,” she writes in Dolphin Mysteries. “but to the trained observer, this conveys agitation or aggression.” Plus, they may have been caught in places like Taiji, where dolphins are also slaughtered, as The Cove showed.

Even though the ads are just a small part of the program, they’re the biggest reason tour guides say no, Powell says. To display the Dolphin Smart sticker, the tour companies can’t show or describe people touching, swimming or communicating with dolphins–or dolphins begging. “Typical dolphin begging behavior generally entails an animal that approaches people in a begging pose, with its head fully out of the water,” the guidelines say.

Powell hopes to expand the Dolphin Smart program, which started with four Florida tour groups in the Keys in 2007, to a broader area.Preliminary research shows both the dolphins and the Dolphin Smart tours doing better. Meanwhile, before the program spreads, watch out for that smiling dolphin. It may be a sign that either the operator isn’t treating dolphins right or that they’re overpromising what you’ll see. Either way, something to avoid.

Want to See Dolphins Around the Country?

Where Can You See More Animals in the Southeast?

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