the park has ireland's only remaining wild herd of native deer ("cervus elaphus"), comprising approximately 700 individuals. an increase from 110 individuals in 1970. they are found in upland areas of the park, mostly on mangerton and torc mountains. this herd has been continuously in ireland for 4,000 years, since the return of red deer to the island, possibly aided by humans, after the last ice age, approximately 10,500 years ago. they were protected in the past by the kenmare and muckross estates. the herd is not completely pure because stags were introduced to the herd to improve antler quality in the 19th century.