The Secret Lives of Dolphins

By staff March 1, 2008

The skinny kid with the glasses really wanted to work at Mote Marine Laboratory. He would do anything to work there—cut up fish, clean the tanks, sweep up—anything.

His name was Randy Wells. His family used to live in Peoria, Ill. Up there, he had watched Flipper on TV and read Jacques Cousteau’s books, but that was as close as he could get to the undersea world that so fascinated him.

Now here he was living in Sarasota, on Siesta Key—and nearby was a marine science lab. This was his chance to stop watching Cousteau and actually be Cousteau!

The only problem was that Mote didn’t want him. He was too young—just 16.

Then one day in 1969, a man named Blair Irvine walked into his dad’s real estate business, looking for a house. Irvine mentioned he was a scientist and he had just been hired at Mote. Irvine wound up getting a sales pitch on a potential assistant, too.

Wells’ dad “told me about this really bright kid who was really bored at school,” Irvine recalls. Intrigued, Irvine agreed to give the boy a chance.

At first, Wells cut up fish, cleaned the tanks and swept up. But Irvine had a contract from the Navy to study bottlenose dolphins. So soon that’s what Wells was working on too, helping to train a dolphin named Simo.

More than 30 years later, Simo is long gone, and Irvine lives on the other side of the country. But Randy Wells is still at Mote, and he’s still studying dolphins. The research he and Irvine began so long ago has become the longest-running study of wild dolphins in the world—37 years old and still going strong.

These days Wells is no longer a skinny kid. He’s 53, a veteran marine biologist whose beard is streaked with gray, someone sought out by scientists around the world for his expertise on dolphins. He now oversees a team of nearly 60 staffers, graduate students, volunteers and student interns.

He easily rattles off the names of five generations of dolphins in one family, tells stories about their behavior and identifies the places in the bay where they like to hang out—all while steering a boat through choppy waves and keeping an eye peeled for a tell-tale dorsal fin breaking the surface.

Not bad for a kid whose first job nearly required him to be shark bait.

* * *

The goal of Irvine’s original study was dictated by the Navy: Train a dolphin to attack a shark and chase it away from a diver. If it worked, Mote would get to train a whole squad of dolphins to protect Navy divers in shark-infested waters.

Irvine planned to spend a year training Simo at Mote with different kinds of sharks. Then would come the ultimate test: Irvine would take Simo and his teenaged assistant down to Bimini and put them in the water together. Then his assistant would “draw the sharks in and then have the dolphin demonstrate how it keeps them away,” Wells recalls, chuckling.

During his training at Mote, Simo did all right with lemon sharks and sand sharks, Wells says. The dolphin would chase them off, just as they had trained him to do.

But every time Irvine put a bull shark in the tank, Simo “would freak out completely,” Wells says, grinning.

Unfortunately, a bull shark was exactly the kind of shark the Navy wanted Simo to attack. After Simo’s repeated failures with the bull shark, Irvine notified the Navy that the plan wouldn’t work. Wells claims to have mixed emotions about the outcome.

“I didn’t get the trip to Bimini,” Wells says. “But I didn’t get the last vacation I would ever take, either.”

With the Navy-sponsored training over, he and Irvine released Simo into the Gulf of Mexico. The dolphin leaped three times and disappeared, never to be seen by the scientists again.

But the notion of studying dolphins didn’t go away—it just grew. Soon Irvine and Wells were experimenting with ways to tag wild dolphins in the bay to see where they went.

To their surprise, they found that most of the dolphins in Sarasota Bay didn’t stray far at all. The bay offered plenty of fish to eat—pinfish, pigfish, spot and mullet were all on the menu—and the temperature didn’t get too cold. They would spend the summer in the shallow seagrass beds, then in winter move into the deeper parts of the bay, but that was the extent of their migration. Since they could breed and feed in nearly ideal conditions, most had no reason to go anywhere else.

Irvine and Wells captured some of the dolphins to take their vital statistics, then released them. They documented where the dolphins went and what they did. Then their funding sputtered out, “and it was catch as catch can,” Irvine says.

But Wells stuck with it, even when he went away to college, even as he pursued a Ph.D. He would come back on weekends or holidays to continue the dolphin study.

“He was like a bulldog,” says Irvine, who left marine biology years ago. “He never let it go.”

Wells and Irvine discovered that about 150 Atlantic bottlenose dolphins use Sarasota Bay on a regular basis. The Mote-based research, which is run jointly with the Chicago Zoological Society, has documented some 35,000 sightings of Sarasota Bay’s dolphins since 1975. The catalogue of Sarasota Bay dolphins contains 3,900 different animals.

One dolphin, Killer, has been spotted 1,100 times over the course of the study, making it one of the best-documented dolphins in history.

“Killer was one of the first ones we tagged in the 1970s, and she was a bit of a handful,” Wells says, explaining the name.

The number of dolphins in the bay at any moment varies. The peak came in 2002, when Wells’ crew counted 182, but in 2006 it dropped to 152.

The Sarasota dolphins aren’t exactly a “community,” because some dolphins do wander away. One male left the bay and returned eight years later. Some go north to Tampa Bay on a somewhat regular basis. Some of the females breed with males from other areas. But because they are a coherent unit, largely contained in a 48-square-mile area, they are considered a distinct population.

Examining one dolphin population for so long “allows us to put together pieces of their lives in ways that wouldn’t otherwise be possible,” Wells explains.

Trying to put the pieces together, to figure out the dolphins’ behavior—that’s almost all Wells thinks about.

“I dream about these creatures sometimes,” he admits.

* * *

The glare of the August sun bounces off the waves, making them shine like a thousand tiny spotlights. Wells steers the boat through the northern reaches of Sarasota Bay headed for the Cortez Bridge. The boat slides beneath its shadow as trucks rumble overhead.

Wells and his field coordinator, Jason Allen, squint at the shimmering water ahead, searching. Suddenly a dark fin slices through the brightness, there and gone.

Allen snaps a photo, then studies the digital image of the fin. After checking the fin’s nicks and notches, Allen calls out, “F173.”

Another dolphin identified. Wells nods at the 28-year-old Allen, then mentions that F173 is a juvenile and its mother is Pumpkin.

“There are a bunch of juveniles out there,” Wells comments. “Juvie girls, that’s the future of the population right there. They’ve got an incredibly long reproductive cycle.”

Bottlenose dolphins can grow to more than nine feet long and weigh up to 600 pounds. They are social and highly intelligent, but under certain circumstances they can be violently aggressive, battling among themselves by using their flukes or their teeth, sometimes even ramming each other.

And their sex lives can seem downright promiscuous, featuring both heterosexual and homosexual couplings, no matter the season, sometimes with other dolphin species.

One of the most intriguing discoveries the Mote study has turned up is that more than half the males form what are known as “pair bonds,” with two male dolphins spending virtually all their time swimming together and even teaming up to court a female. The male pair bond can last all of the animals’ lives.

When Wells and Irvine began their dolphin study, most of what was known about the species came from studying captive dolphins. People thought dolphins lived perhaps 25 years in the wild.

The Mote researchers discovered that dolphins can live twice that long, and that some females, which begin bearing young around age six, can bear calves into their 40s. One, named Jagged Mama, had a calf at age 48.

The scientists can figure out a dolphin’s age by capturing the dolphin, pulling one of the 20 to 25 teeth in its cone-shaped beak and then sectioning it to measure the growth. But there’s little need to do that anymore, Wells says.

“Most of these animals, we know their age because we know their mothers and we’ve been following them over time,” he explains. “There are dolphins older than me on this project.”

Well, just a couple of them, he adds with a chuckle.

* * *

Soon, the sky turns gray. Drops of rain dimple the water. Suddenly three, four, five fins pop up near the boat. It’s like being in a tank at Sea World.

Dolphins signal each other underwater with whistles and chirps, Wells explains as he eases the 24-foot Palmer along after them. Heavy rain hitting the surface sounds like white noise, so they swim closer together. That way, in spite of the rain, they can still hear each other, he says.

Then he warbles a few bars of Singin’ in the Rain.

As well as Wells knows the dolphins, he doubts that the dolphins know him at all.

“I think they recognize when our boat approaches,” he says. “Most boats go by at high speed. We have had occasions over the years where mothers would bring their babies over to our boat and let us do the babysitting for them while the mom goes off and feeds.”

And on one memorable occasion, Wells says, a dolphin tangled in fishing line appeared to seek out his boat for help getting free.

One of the dolphins Wells and Allen have spotted today is named Nosepicker because its fin seems to have a finger-like hook on its tip. They are quick to explain that they didn’t come up with the name. A federal official whose agency was providing the funding for one part of the study dreamed that one up.

Nosepicker usually hangs out in Tampa Bay, near Safety Harbor, but this summer while visiting Sarasota Bay it gave birth to a calf, they say. They’re particularly delighted when they see calves like Nosepicker’s, which they call Yoys, short for “young of the year.”

Other occasional visitors from Tampa Bay have helped the Sarasota Bay dolphins. For instance, one frequent visitor from Tampa Bay named Pecan Sandie taught the other dolphins a new way to hunt for food, a method Wells calls “kerplunking.”

Pecan Sandie drags its tail through the water, creating a geyser of water that creates bubbles beneath the surface. The bubbles flush out small fish, making them easier to catch and eat.

Now that Pecan Sandie has taught other dolphins in Sarasota Bay how to do its move, Wells says, “They’ll kerplunk in a circle sometimes, and then go in and feed.”

Wells has traveled the globe teaching other scientists his techniques for capturing dolphins, and visitors have flocked to Mote to study with the master. On this particular trip he’s accompanied by an Indian biologist, looking for tips he can use with a species in the Ganges River that’s endangered by commercial fishing and pollution.

Over the years Wells has seen changes in Sarasota Bay. Some are good—the city stopped dumping raw sewage—and some not so good—speeding boats have increased. Research by Wells’ team has shown that Sarasota Bay’s dolphins encounter a boat every six minutes on average. Since there are 40,000 registered boats around the bay, that’s not a surprise, Wells explains.

“It gets crazy out here. We won’t come out and do any work on the weekends because so many boats are passing by,” Wells says. The Fourth of July is particularly bad—and that’s right in the middle of the dolphins’ calving season, he says.

Then there’s all the polluted stormwater runoff, which pours into the bay every time there’s a hard rain. The pollution carries a variety of contaminants, including pesticides.

Pesticide residue has shown up in dolphin blubber and milk, and it could be the reason some calves die, Wells’ studies have found. Other environmental contaminants have him concerned as well. Some male dolphins register PCB levels of over 800 parts per million, far above the 1 part per million considered safe for humans.

Considering the problems with pollution, the loss of mangroves along the shoreline and the increase in boating and development, Wells says, “The big surprise is that the dolphins are still here. They haven’t gone away.”

* * *

These days the dolphins seem to prefer the less developed north end of the bay, near Cortez, because the water there is clearer and quieter, Wells says. “There are a lot of seagrass beds here and a lot of the mangroves along the shore are still intact,” he explains.

But that didn’t help when a major red tide bloom hit last year, wiping out many of the fish the dolphins eat. Hungry, some dolphins went after anglers’ baited hooks and wound up tangled in fishing gear. Two of them died.

Finally, near noon, the rain lets up. As Wells steers the boat back under the Cortez Bridge, a dolphin pops up off the port side, grabs a pinfish, rolls on its back and dives beneath the surface.

Wells watches it go. It was moving too fast to identify and he’s not sure which dolphin it was. He’s just happy to be on the water and not stuck in his office, trying to raise money to meet the study’s $1.1-million annual budget.

“You have to be creative with your funding,” he explains. “We’ve outlasted most of our funding sources.”

It’s a well-organized office, with nautical charts on the wall and one bookshelf lined with dissertations written by Wells’ many students over the years. There’s a poster from China about a kind of dolphin that Wells was supposed to help save, except it turned out to be already extinct, the apparent victim of severe industrial pollution.

The office windows look out on the bay, and sometimes Wells’ gaze strays over to look out to the water, where the dolphins are, where he ought to be, instead of stuck indoors, tapping on a keyboard.

“The whole idea of sitting in front of a computer trying to find money for people to do what I want to do, there’s something wrong with that,” Wells grumbles.

He has no idea how many more years his dolphin study will continue—perhaps for as long as there are dolphins in Sarasota Bay.

“The changes I’ve seen over the course of this study,” he says, “give me hope that maybe the dolphins won’t ever leave. Maybe we can learn to co-exist.”

Craig Pittman, an environmental reporter for the St. Petersburg Times, is a three-time winner of the Waldo Proffitt Award for Distinguished Environmental Reporting in Florida, and a series he co-wrote with Matthew Waite on Florida's vanishing wetlands has won a pair of national awards for investigative reporting from the Society of Environmental Journalists. A book version of that series is being published by the University Press of Florida this year.

Dolphin Discoveries

Ten things Wells has learned in his research.

1. About 150 Atlantic bottlenose dolphins use Sarasota Bay as home year-round.

2. Males pair up with each other at an early age, and the pair bond lasts until death.

3. Females can have calves well into their 40s.

4. Dolphins can live into their 50s in the wild.

5. Dolphins sometimes whack fish into the air with their tails, stunning them so they can be easily caught and eaten.

6. Some dolphins drag their tails through the water, creating a geyser of water that leaves a trail of bubbles beneath the surface, flushing out fish so they’re easier to catch.

7. When Sarasota Bay’s population of the dolphins’ main predator, the shark, was depleted by overfishing, sting rays then became the top dolphin predator.

8. Pesticide residue has shown up in dolphin blubber and milk, and could be the reason some calves die.

9. Some male dolphins have registered PCB levels of over 800 parts per million, far above the 1 part per million considered safe for humans.

10. When red tide wiped out much of Sarasota Bay’s fish, hungry dolphins tried to steal bait and got tangled in fishing gear. Two died.

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