Study of world-famous Stingray City finds human interaction drastically alters stingray behavior

Mar 18, 2013
Tourists interact with Southern stingrays at Stingray City/Sandbar at the study site in the Cayman Islands. Credit: Guy Harvey

Stingrays living in one of the world's most famous and heavily visited ecotourism sites—Stingray City/Sandbar in the Cayman Islands—have profoundly changed their ways, raising questions about the impact of so-called "interactive ecotourism" on marine wildlife, reports a new study published March 18 in the journal PLOS ONE.

Researchers from Nova Southeastern University's Guy Harvey Research Institute in Hollywood, Fla., and the University of Rhode Island studied the southern stingray population of Stingray City—a sandbar in the Cayman Islands that draws nearly a million visitors each year to feed, pet and swim with its stingrays—to assess how the intensive ecotourism has affected the ' behavior.

"Measuring that impact is important because there's a lot of interest in creating more of these interactive ecotourism operations, but we know little about the life histories of the animals involved or how they might change," said study co-author Guy Harvey, who initiated the project.

The researchers found that Stingray City's stingrays show distinctly different patterns of activity than their wild counterparts, who don't enjoy daily feedings or close human contact.

"We saw some very clear and very prominent , and were surprised by how these large animals had essentially become homebodies in a tiny area," said study co-author Mahmood Shivji, director of the Guy Harvey Research Institute and NSU Oceanographic Center professor, who led the study.

Wild stingrays are active at night and solitary—they forage through the night over large distances to find food, and rarely cross paths with other stingrays. To see if Stingray City's fed stingrays stray from this behavior, Mark Corcoran, lead author of the study who did the research as part of his graduate work at NSU, and the research team tagged and monitored both wild and fed stingrays over the course of two years and compared their patterns of movement.

They found that fed stingrays swapped their normal nighttime foraging for daytime feeding, and in contrast to their wild counterparts, began to rest at night. They also didn't mind rubbing shoulders with their neighbors: At least 164 stingrays abandoned the species' normal solitary behavior, crowding together in less than a quarter square mile of space at Stingray City. They even formed schools and fed together. The fed stingrays mated and became pregnant year-round, instead of during a specific mating season, and also showed signs of unusual aggression, biting each other more frequently than their wild counterparts.

These results suggest that human-provided food can dramatically change how even large, highly mobile ocean animals behave—with potentially serious consequences, the researchers conclude.

"There are likely to be some health costs that come with these behavior changes, and they could be detrimental to the animals' well-being in the long term," Shivji said.

Stingray City means big business in the Cayman Islands, where each stingray generates as much as $500,000 annually in tourism income, Harvey said. The team plans to continue to monitor Stingray City's population to track its health—and the industry's impact—over time.

"Right now, these animals have no protection at all," Harvey said. "Without more studies like these, we won't know what that means for the wildlife or if we need to take action. It's unclear how much of the stingray's daily diet comes from tourism provided food, but the good news is we have seen the animals forage when tourists are absent suggesting that these animal are not completely dependent on these handouts."

Explore further: Male monkey filmed caring for dying mate (w/ Video)

add to favorites email to friend print save as pdf

Related Stories

First definitive guide to Borneo's sharks and rays

Jun 10, 2010

(PhysOrg.com) -- Which island of South-East Asia has the most stingray species in the world? According to the new book 'Sharks and Rays of Borneo', the island of Borneo has 30 different stingrays: not surprising ...

Recommended for you

Male monkey filmed caring for dying mate (w/ Video)

Apr 18, 2014

(Phys.org) —The incident was captured by Dr Bruna Bezerra and colleagues in the Atlantic Forest in the Northeast of Brazil.  Dr Bezerra is a Research Associate at the University of Bristol and a Professor ...

Orchid named after UC Riverside researcher

Apr 17, 2014

One day about eight years ago, Katia Silvera, a postdoctoral scholar at the University of California, Riverside, and her father were on a field trip in a mountainous area in central Panama when they stumbled ...

In sex-reversed cave insects, females have the penises

Apr 17, 2014

Researchers reporting in the Cell Press journal Current Biology on April 17 have discovered little-known cave insects with rather novel sex lives. The Brazilian insects, which represent four distinct but re ...

Fear of the cuckoo mafia

Apr 17, 2014

If a restaurant owner fails to pay the protection money demanded of him, he can expect his premises to be trashed. Warnings like these are seldom required, however, as fear of the consequences is enough to ...

User comments : 2

Adjust slider to filter visible comments by rank

Display comments: newest first

katesisco
2.3 / 5 (3) Mar 18, 2013
If one was to note the human condition, it would compare to the description of how the stringrays, formerly wild, changed their behavior upon dependence for food.
JWnTX
1 / 5 (2) Mar 20, 2013
You know what? In the end, they're friggin' stingrays. They're not being harmed and they're providing a chance for people to see them up close and personal. Until and unless they adversely affect the humans who seek contact with them, this is research money in search of a cause as far as I'm concerned and proof that there's way too much of it floating around.

More news stories

Easter morning delivery for space station

Space station astronauts got a special Easter treat: a cargo ship full of supplies. The shipment arrived Sunday morning via the SpaceX company's Dragon cargo capsule.