The whale shark is the biggest fish in the world. It has a massive body that can reach up to 18 meter (60 feet). Its coloration is gray or dark blue on its back, with circular spots and light colored white or yellowish horizontal and vertical lines and a white belly. In Mexico these patterns give the whale shark its local name: "domino."

Named after the shark’s nickname Domino: The Mexican Atlantic Whale Shark Project was created in Mexico in 2003. The project was established for whale shark conservation and allows whale shark tour operations to run Whale Shark excursions for visitors that would like to swim with the animals. 

The whale shark is present in several international protection lists; the sharks are listed as “Vulnerable” on the IUCN Redlist. In Mexico the whale shark is protected by the Mexican Secretary for Natural Resources (SEMARNAT).

To protect the whale sharks and to give greater security to the tourists who visit them during whale shark season the following rules and regulations have been established for whale shark tours in Yucatan, Mexico:

•    The conditions established in the permits will be respected.
•    Tourists will be informed, before the trip, regarding the conduct they should use during activities with the whale sharks.
•    Tourists will only be taken to swim freely and snorkel.
•    The number of boats in the whale shark sighting area will be limited.
•    Boats longer than 12 m, or 40 ft , are not allowed.
•    The maximum capacity for each boat depends on its size: 6,7,8,9, or 10 people for boats with 25, 26, 27, 28 and 29 ft or more, respectively.
•    The maximum velocity of 3 knots for boats within the sighting area will be respected.
•    Tourists will be asked to use biodegradable sun blocks and sun tan lotions.
•    The boat will be at a distance of at least 10m from the animals.
•    There will be a maximum of one boat per whale shark.
•    The tourists will be at least 2m away from the whale shark at all times.
•    There will always be a guide with a maximum of two people in the water.
•    Use of life jacket is compulsory.
•    The maximum time of permanence per boat with the whale shark will be of 30 minutes when there are other boats waiting.
•    The distance between boats will be of 100m.
•    Activities will start half hour after sunrise until half hour before sunset, always with day light.
•    Trash will not be left in the area.
•    Liquid residues (gasoline, lubricants, cleaning products, etc) will not be discarded in the sea.
•    Recorders, microphones or any apparatus that produces noise or sounds that can disturb the sharks will not be used.
•    Monitoring will be supported to assure that the agreements and the dispositions established in the permits are fulfilled.
•    Indications made in training courses will be followed to improve the services provided.

For more information on Whale Shark Tours please visit the link.