It is not that extensive though the Isla Contoy presents one of the few land ecosystems in natural state in the Mexican Caribbean on its 238-hectare surface.
The hand of man has not intervene in any way whatsoever in here, therefore it is possible to realise scientific investigations regarding the processes of colonisation, dispersion and adaptation of many flora and fauna species in far-off places on the continent and under adverse conditions.
Located on the limit of the Gulf of Mexico and the Caribbean Sea, in the Municipality of Isla de Mujeres (State of Quintana Roo), the Island has a length of 8.75 kilometres and its width fluctuates between 200 metres on the northernmost tip and 700 in its central part. Regarding the morphology, Contoy is flat and long although it has rough grounds in some sectors.
This originates a rather similar land environment, however 98 plant species have been identified (70 percent of them mangroves). Regarding the sea area, there are reports of 41 species of large algae and 2 of seaweeds.
Besides the land environment, Contoy has other natural environments such as coastal dunes, restricted lagoons, an intercontinental canal, an opened beach and a superb cluster of coral reefs in its southern zone, which marks the beginning of the Great Mesoamerican Reef, the second largest on the planet.
In spite of the inexistence of mammals on the island, due to the lack of fresh water sources, the Park hosts an attractive fauna amongst which 152 bird species have been identified, with the frigate (Fregata magnificens), the cormorant (Phalacrocorax auritas), the brown pelican (Pelecanus occidentales), and the river alder (Sula leucogaster) standing out; besides 14 types of reptiles and 6 of butterflies.
On the other hand, 17 species of scleractinious corals, 14 of gorgonaceous and 12 sea sponges have been registered in the southern part, the one with the most biological diversity.
But the Island is not important for its coral diversity alone, but for being the nesting zone of the brown pelican, the largest in the Atlantic, refuge for the loggerhead sea turtle (Caretta caretta), the white turtle (Chelonia mydas) and the carey (Eretmochelys imbricata), which arrive in the summer to lay their eggs, and for being the habitat of the black mangrove (Avicennia germinans), a species protected in Mexico.
The waters of Contoy, from the Mayan word "Pontoj" meaning Pelican, are extremely rich in nutrients such as plankton, which originates an abundance of marine species with 234 registered so far, being the shark whales (Rhincodon typus) and the mantle rays (Manta birostris) the most prominent inhabitants.
For all these reasons the Island was declared Natural Park and Flora and Fauna Refuge in 1961, becoming the first protected area within the State of Quintana Roo. In 1998 it would ascend to the category of National Park.
It is located at 50 kilometres from Cancun and at 32 from Isla de Mujeres. The boats authorised to enter the Park weigh anchor at these two places and at Puerto Juarez as well.
According to the regulations enforced by the authorities only 200 individuals a day can enter to the 2 hectares that the State has destined for tourist purposes.