Amigos de Isla Contoy
Lonely Planet review for Amigos de Isla Contoy
The trip gives you about two hours of free time to explore the island's two interpretive trails, skim through materials in the visitors center and to climb the 27m-high observation tower. For around $100 per person, a park biologist will take you on a tour of Laguna Puerto Viejo, a prime nesting site; funds go toward park upkeep and research projects. Contact the Park Headquarters on Isla Mujeres.
Amigos de Isla Contoy has a website which has good information on the island's ecology.