Antonio Rivera; a member of United for Conservation, one of the project partners, Carlos Manterola; and a photographer with the National Geographic Society, Steve Winter.

We quickly down a frugal breakfast of coffee and cookies. The trucks are ready. Our pack of dogs is led by Sombra (whose name means "Shadow"), a bitch of undefined lineage, who seems anxious to start the difficult run in the jungle. One of the dogs has barkedall night, as though he could sense the presence of a jaguar. Just after four in the morning, we start off on the only dirt road that goes into the jungle and begin our search for the jaguar.

Revered by the Mayas and Aztecs as powerful, mysterious deities, jaguars are among the most attractive and charismatic species of animals in the Americas. Until the beginning of last century, jaguars ranged over vast expanses of land, from the holm oak forests and arid bush of Arizona and New Mexico in the southern United States to the province of Misiones in northern Argentina. Indiscriminate hunting and the destruction of their habitat have eradicated them in many areas, to the point that the entire species has practically disappeared from the United States and El Salvador and is endangered in many other countries, including Argentina, Mexico, Costa Rica, Ecuador, and Panama.