In May 2004, a dead white-tailed deer (Odocoileus virginianus) radiocollared in 1991 was found in Carbondale, Illinois, and was aged at 16 years old via cementum annuli analysis. She was a member of an unharvested, free-ranging population and likely died of natural causes. Given the average longevity of deer in unharvested populations at about 8 years of age, our finding is quite rare. Increased longevity of deer can heighten lifetime reproductive output, which may contribute to elevated deer abundance and concentrated herbivory in urban settings.
Nielsen, Clayton K., Swan, Jennifer L. and Schauber, Eric M. "Record of a Sixteen-year-old White-tailed Deer (Odocoileus virginianus) in Carbondale, Illinois: a Brief Note.." Transactions of the Illinois State Academy of Science 104 (Jan 2011): 147-149. doi:http://ilacadofsci.com/archives/400.