Death of Last U.S. Jaguar

The Phoenix Zoo had the unfortunate task of euthanizing the last living wild jaguar in the United States in March. Dubbed "Macho B" by researchers who had photographed him sporadically for more than a decade, the 16-year-old animal was accidentally captured by the Arizona Game and Fish Department in February after being caught in a snare set to catch cougars and black bears for research.

The jaguar was sedated and fitted with a radio collar for tracking, and then released. In the following weeks, researchers began to notice Macho B’s abnormal weight loss and limited movement, which led to his intentional recapture on March 2. The decision to euthanize came when they discovered he was suffering from severe kidney failure.

Dr. Dean Rice, the executive vice president of the Phoenix Zoo who assisted in Macho B’s necropsy, told the Arizona Daily Star that the jaguar’s kidneys had likely started deteriorating prior to the capture, but that the stress of being trapped and tranquilized exacerbated the problem, which led to the animal’s death. State officials say, however, that kidney failure is common in older cats, and that Macho B’s lifespan was longer than any other known wild jaguar.

Jaguars, who once used to inhabit much of the southern U.S., were added to the federal Endangered Species List in 1997. Macho B was the only known surviving individual in the wild.

The Center for Biological Diversity in Tuscon, Ariz., however, won a federal court case to help preserve critical habitat for jaguars and implement a species recovery plan. By next year, the U.S. government will issue a new decision on jaguar protection, which may include the species’ reintroduction into its native lands.