Mexico's ecological diversity is among the broadest of any country in the world, with an abundance of ecosystems ranging from the northern deserts to the central conifer forests, and the southern tropical rainforests. Mexico also supports 111 million people and welcomes more than 20 million visitors each year. Tourism is one of the country's biggest and most lucrative industries, and while tourism has brought jobs and growth to much of Mexico, it has also created and even accelerated many of Mexico's ecological problems. Cancún might be the highest-profile example: Rapidly developed from a rural outpost to an international resort destination, Cancún imported turf from Florida for its golf courses, inadvertently introducing a disease that wiped out the local coconut palms. The region's mangroves, a key habitat for native species and vital to protecting the land from hurricanes and erosion, have also suffered.

However, tourism has also encouraged development of ecological conservation. Mexico is home to seven of the world's eight species of sea turtle, though the entire turtle population was decimated on both coasts as a result of tourism growth and local overfishing. Recent success stories such as Puerto Escondido, in Oaxaca, where sea turtles are now protected by the locals, or the Riviera Maya, in the Yucatán, where marine biologists are working with hotels to guard nesting turtles and their eggs, have demonstrated the benefits of linking tourism with local knowledge.

Mexico's people are proud of their land and culture, and through your travels, especially in rural areas, you will likely encounter ejidos and cooperativos, or local cooperatives, that offer small-scale tourism services -- this may be as simple as taking visitors on a boat ride through a lake or as visible as controlling access to archaeological ruins. Ejidos will also run tours to popular ecotourism destinations similar to those offered by large travel agencies. When you deal with ejidos, everyone you encounter will be from the community and you know that your money goes directly back to them. States with a strong network of cooperatives include Chiapas, Oaxaca, Quintana Roo, and Yucatán.

The Mexican Caribbean supports the Great Mesoamerican Barrier Reef, the second-largest reef in the world, which extends down to Honduras. This reef and other marine ecosystems face increasing pressure from sedimentation, pollution, overfishing, and exploitative recreational activities, all newly associated with growing regional tourism. The Coral Reef Alliance (CORAL; www.coral.org) is an example of an organization that, by teaming up with the World Wildlife Fund (WWF; www.wwf.org) and United Nations Environmental Programme (UNEP; www.unep.org), has been working to address threats to the Mesoamerican Barrier Reef and improve environmental sustainability throughout the region. CORAL partners with Mexican Amigos de Sian Ka'an, Conservation International, and the Cozumel Reefs National Park in an effort to build sustainability into mass tourism (such as cruise ships and hotels). CORAL assists marine tourism operators in implementing a voluntary code of conduct for best environmental practices. CORAL is soon to spread its influence to the Yum Balam region of the Yucatán Peninsula, where guidelines for whale shark interactions are greatly needed.

Biodegradable Sunscreen -- Recent scientific studies have shown that the chemicals in commercial sunscreen can do long-term damage to coral reefs, collect in fresh water, and even build up in your own body system. The Riviera Maya, Mexico's Caribbean Coast, receives more than 2.5 million visitors every year, many of them drawn to its rare marine environment -- a unique combination of freshwater cenotes and the world's second-largest coral reef. A few ounces of sunscreen multiplied by 2.5 million is equal to a substantial amount of harmful chemicals suspended in the ocean and fresh water. That's why tours to the Sian Ka'an Biosphere Reserve and water parks Xcaret and Xel-Ha ask that you use only biodegradable sunscreen or wear none at all when swimming in their ocean or cenotes.

The label of a biodegradable sunscreen should state that it is 100% biodegradable (and only 100% will do). You can buy it at the parks, but you'll get a better price from local markets. If you're curious, you can obtain a list of banned chemicals by contacting the parks directly. Buy a supply of biodegradable formula before you go from www.mexitan.com or www.caribbean-sol.com.

Animal-Rights Issues

Bullfights -- Bullfighting is considered an important part of Latin culture, but before you attend a correo, you should know that in all likelihood the bulls (at least four) will ultimately be killed in a gory show. That said, a bullfight is a portal into understanding Mexico's Spanish colonial past, and traditional machismo is on full display. Bullfights take place in towns as different as Tijuana and Puerto Vallarta, and they afford a colorful spectacle like no other, with a brass band playing; the costumed matador's macho stare; men shaking their heads at less-than-perfect swipes of the cape; and overly made-up, bloodthirsty women chanting "Ole," waving their white hankies, and throwing roses, jackets, and hats at the matador's feet. There is also the extremely minuscule chance that if the bull puts up a good enough fight or pierces his horn through the matador's leg, he will be spared for breeding purposes. It does happen, if only rarely. To read more about the implications of attending bullfights, see the website of People for the Ethical Treatment of Animals (PETA) at www.peta.org.

Swimming with Dolphins -- The capture of wild dolphins was outlawed in Mexico in 2002. The only dolphins added to the country's dolphin swim programs since then were born in captivity. This law may have eased concerns about the death and implications of capturing wild dolphins, but the controversy is not over. Local organizations have been known to staple notes to Dolphin Discovery ads in magazines distributed in Cancún hotels. Marine biologists who run the dolphin swim programs say the mammals are thriving and that the programs provide a forum for research, conservation, education, and rescue operations. Animal rights advocates maintain that keeping these intelligent mammals in captivity is nothing more than exploitation. Their argument is that these private dolphin programs don't qualify as "public display" under the Marine Mammal Protection Act because the entry fees bar most of the public from participating.

Visit the website of the Whale and Dolphin Conservation Society at www.wdcs.org or the American Cetacean Society, www.acsonline.org, for further discussion on the topic.

Note: This information was accurate when it was published, but can change without notice. Please be sure to confirm all rates and details directly with the companies in question before planning your trip.