Tourists feeding stingrays have changed the creatures' feeding habits along with behavior and mating habits, a new study finds. Researchers say the research finding raises questions about the impact of interactive tourism on marine wildlife, reports e!sciencenews.

Stingrays are commonly found in shallow coastal waters in temperate regions, according to the National Geographic. Their toxin can be fatal to humans.

The study was conducted by researchers from Nova Southeastern University's Guy Harvey Research Institute in Hollywood, Fla. and the University of Rhode Island who assessed the population and behavior of Southern stingrays, Dasyatis Americana, found in the Stingray City Sandbar, Grand Cayman, which draws about a million visitors each year.

"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 Guy Harvey, co-author of the study, according to e!sciencenews.

Researchers found that stingrays in Stingray City have distinct feeding habits than stingrays living in wildlife.

For the study, researchers studied stingray movements for over two years by attaching wild and tourist-fed stingrays with sensors.

Stingrays are known to be solitary feeders, foraging at night and rarely crossing the paths of other stingrays. The present study showed that the stingrays fed by tourists have started feeding in the day and resting at night. Their behavior has also changed, with stingrays in tourist places forming groups and getting aggressive, and sometimes even attacking other stingrays. Aggression among these creatures in the wild is fairly uncommon.

The study has also shown that while wild stingrays reproduce only during a particular season, stingrays in tourist spots mated and reproduced throughout the year.

The study is published in the journal PLOS ONE.

"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," said Mahmood Shivji, director of the Guy Harvey Research Institute and NSU Oceanographic Center professor, co-author of the study, reports e!sciencenews. Stingray tourism generates a lot of money for Cayman Islands, sometimes $500,000 for each stingray, Harvey added.