. The gray oak woodlands are found in slightly moister soils than the pinyon woodlands. The richest and most diverse of the woodlands and forests in the Davis Mountains are the mesic forests found from . These forests are found in stream valleys and other well-watered areas. Indicator species are ponderosa pine and southwestern white pine, plus two small groves of quaking aspen at elevations of at the base of the cliffs surrounding the summit of Mount Livermore. Aspens are more characteristic of the higher elevations in the Rocky Mountains. The mesic woodlands are remnants of past glacial ages in which the climate of West Texas was more humid and cooler than at present. Fauna Over 277 species of birds have been seen at Davis Mountains State Park. Many species found here are characteristic of more northerly mountain climes or alternatively of nearby Mexico, including 10 species of hummingbirds. Large mammals found here include whitetail deer, mule deer, elk, black bear, cougar, pronghorn, peccary, and introduced species such as aoudad and feral hogs. There is only one record of grizzly bears in Texas; it was killed in the Davis Range in 1890. Several private ranches in the Davis Mountains offer hunting opportunities. Climate Nearly all of the Davis Mountains fall into the climate classification of BS (semiarid steppe) in the Köppen climate classification system. However, the highest elevations may transition into a cooler, wetter Cfb climate (subtropical humid with warm summers). Conservation Most of the Davis Mountains are in private ownerships. However, since 1996, the Nature Conservancy has acquired 33,000 acres (130 km²) in the Davis Mountains range, along with conservation easements on 70,000 adjoining acres (280 km²) of private ranchland. The Davis Mountain Preserve is open to the public at specified times. Facilities McDonald Observatory is accessed by Spur 78 from State Highway 118. Spur 78 is the highest state maintained road in Texas at 6,791 feet near the summit of Mt. Locke where the older telescopes of the observatory are located. Spur 77 branches off from Spur 78 providing access to the newer research equipment atop Mt. Fowlkes. Texas separatist standoff The Texas separatist organization known as the Republic of Texas has its origins in the Davis Mountains. On April 27, 1997, the leader of the group, Rick McLaren, staged an attack on his neighbor's house and demanded that he cede his property to the Republic of Texas.