Pronghorn: Return of the Native
By Steve Mark
One of the reasons people come to national parks is to see large animals. The most ubiquitous large animals in North American national parks have been called ungulates. Although this classification for exclusively herbivorous mammals with horns or antlers is no longer used, three families comprise the order Artiodactyla, or hoofed mammals. Members of two families, Cervidae (deer and elk) and Antilocapridae (pronghorn antelope), are found in Crater Lake National Park.
A glimpse of the common Columbian black tail deer, Odocoileus hemionus columbianus, is enough for many visitors to stop and take a second look. The larger and lighter-colored Odocoileus hemionus hemionus whose comparatively long ears give it the name "mule deer" is also often seen. Sometimes it can be difficult to tell these subspecies apart because they can hybridize along the crest of the Cascade Divide, where their respective ranges overlap. Much more rarely seen is the yellow tail deer, Odocoileus virginianus ochrourus. It should not be confused with the two subspecies of O. hemionus or their hybrid because this animal has a distinguishing and largely white tail.
A bigger member of the family Cervidae is the wapiti, though often referred to as elk. The names are a small point of distinction in that wapiti is a Shawnee word from eastern North America, whereas elk originally referred to European moose. Most of them seen in the park are members of a herd which migrates circuitously from the Prospect area (20 miles southwest of Crater Lake) to the northern Klamath Basin. They often utilize the meadows in Munson Valley throughout the summer and into fall. Being no strangers to the southern rim of the Crater Lake caldera, nor even to the top of Crater Peak, the elk can sometimes be seen kicking up dust throughout August and September.
Like the two subspecies of deer, there is reason to believe that the wapiti have undergone some degree of hybridization. This is because of the general belief that hunters greatly depleted the native Roosevelt elk, Cervus canadensis roosevelti, by the early years of this century. State game officials brought a herd of Rocky Mountain elk, Cervus canadensis nelsoni, from Yellowstone National Park and released them into the wild near Fort Klamath in 1917. The two subspecies probably interbred because the Roosevelt elk had not been completely extirpated from the west slope of the Cascade Range in southern Oregon. The park thus plays an important role in perpetuating the existence of a large and striking animal-- though one not fully native by lineage.
Less evident than deer or elk at Crater Lake National Park are pronghorn antelope, Antilocapra americana oregona. As a fully native wild species, the pronghorn is known for its speed (up to 60 mph) and keen eyesight which allows them to spot moving objects three to four miles away. These creatures are generally the size of a small deer and bear cinnamon-buff coloration. Supplying emphatic contrast are black and white markings on the head and neck. Pronghorn have a rump patch which can be spread when the animal is alarmed into a large white rosette, or remain small and inconspicuous when closed. They are not true antelope (in this regard they are like the "elk"), but belong instead to a family of one pronged hollow- horned animals peculiar to this continent. It differs from other hollow-horned mammals by having permanent horn cores. A horn-like sheath covering these bony processes is shed annually.
Within the boundaries of what is now Crater Lake National Park, the earliest record of pronghorn is from 1887. During September of that year one explorer encountered sufficiently large numbers of them on the Pumice Desert to name the place "Antelope Prairie. " Several hundred pronghorn could still be seen there during the late summer of 1896, but hunting pressures associated with encroaching settlement forced their general retreat into the high desert east of the park shortly thereafter. Despite a report of two antelope on the south rim of Crater Lake in 1931, none had been seen in other parts of their original range (which extended from southeastern Oregon to the Cascade Range and included the Klamath Basin) for several decades. By the 1940s, researchers doubted whether anyone might ever again see pronghorn west of U.S. highway 97.
More recent observations, however, show that antelope use the park each summer by way of the Desert Creek drainage. A disappearing snowpack in this part of the park usually makes June and July the best times to see them, though other times of the year should not be discounted. In recent years several individuals have even been spotted near Roundtop, along Crater Lake's northeast rim. They appear to be part of a herd which migrates from the Fort Rock area, some 70 miles northeast of the park. When they are present, the pronghorn seem to prefer the forested habitat between Pumice Desert and the park's east boundary instead of more open areas. This may be due to the pronghorn's characteristically slow natural return to former range, even when hunting has been restricted for more than 80 years. Upon their return to former range, researchers have noticed the pronghorn's inclination to take up forested habitat more often associated with mule deer. These areas can offer sanctuary for antelope, though they may be somewhat different from the open places so characteristic of where they roam.
What makes pronghorn reappearance at Crater Lake interesting is that it seems to be part of a general reclamation of their range after being absent in many places for most of the past century. Even in the flat and open country of the Klamath Basin, where sightings had not been recorded since 1886, antelope have reappeared. Several weeks after an acquaintance of mine noticed a herd of 20 pronghorn in an open field ten miles south of Klamath Falls, I came across a single antelope on highway 62 near Klamath Agency. This occurred in December 1994, when a foot of snow sat along the roadside. Since antelope do not hurdle perceived barriers, it started running along the highway's fog line. By the time we reached a road intersection (which resulted in the antelope heading west toward Agency Lake while I continued southward), we were traveling almost 50 mph. There are few things more impressive than antelope in full flight, but speed alone is not responsible for their apparent recovery in this part of Oregon. Restrictions on hunting, accompanied by state and federal agencies managing for pronghorn throughout eastern Oregon, have brought about this success story.
Like the antelope, deer and elk populations within the park appear to be viable, meaning that they are capable of continuing to perpetuate themselves in this habitat. High elevation and winter conditions, however, make the park a refuge for only part of the year. These animals are dependent on management practices outside park boundaries to sustain them, whether this means protection from poaching or controlled hunting for herd reduction so that starvation is averted.
Steve Mark is the park historian at Crater Lake. He has been editor of Nature Notes since its revival in 1992.
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