The jaguar captured and collared in Arizona a few weeks ago, Macho B, was recaptured by wildlife officials when the big cat’s tracking device showed him to be lethargic. Tests revealed that the jaguar suffered from severe, untreatable kidney failure, a common ailment among older cats. Biologists put the jaguar to sleep the same day. Macho B was estimated to be 14-16 years old.
For more info: National Geographic.