efe_epaSydney, Australia

The saturation of the dolphin-watching market in several Asian countries is endangering the population of the marine mammals, according to an international study released on Friday.

The research focused on seven popular areas of dolphin watching in Cambodia, Indonesia, Malaysia, Thailand and the Philippines between 2008 and 2014, and in almost all cases the market was found to be saturated.

"At this point, the industry ceases to be profitable for individual boatmen who enter it; there are too many players," said Putu Liza Mustika, a researcher of James Cook University, in a statement from the institution.

There are more than 90 operators in Chilika Lake, India, and in Lovina, Bali, Indonesia, and the vessels sailing in these places pose a danger to dolphins because of the large numbers and the lack of appropriate management strategies, according to the study.

Coming from the universities of Melbourne, Australia; Los Baños, the Philippines; Prince of Songkla, Thailand; and Sarawak, Malaysia, the researchers of the study were told by villagers that the number of dolphins has declined dramatically in the tourist zones.

"We know that having too many boats around is not good for dolphins. They can't rest and their feeding is disrupted. It can disturb the mother-and-calf bond, especially because they communicate by sound and whistling. With the sound of the boat engine being so loud, the mother cannot hear the calf and there is a rupture in their bond," said Mustika.

The group of scientists have proposed to introduce a regulation that controls the dolphin watching in those places, the number of boats and the maximum approach distance, as well as the time limit of the activity.

In 2008, there were 857 individual operators of dolphin watching in Asia and it is estimated that this number have doubled, at least at present.