OSLOB, Cebu, Philippines — The increasing number of tourists coming to Oslob, a quiet, laidback town in the southern part of Cebu, to view the famed whale sharks or butanding, as they are called in the local dialect, which have appeared in waters here are alarming local officials, prompting the latter to enact an ordinance to protect the huge water mammals.

The ordinance, Oslob Mayor Ronald Guaren said, seeks to regulate whale shark-watching activities in his town as tourists come in groups daily following media coverage of the presence of friendly butanding in Oslob's sea waters.

The ordinance requires the registration of fishermen to be allowed to guide tourists and handle the sea animals. It also strictly prohibits motorboats from going near the butanding, Guaren said.

The town plans to set up ticketing and briefing offices, the latter for giving visitors an orientation about the whale sharks and providing them with safety instructions.

Guaren said that since the whale sharks appearing in local waters here were featured by national media as well as by local newspapers, groups of divers have flocked daily to the site.