Desert Bighorn Sheep
Desert bighorn sheep (Ovis Canadensis nelsonii) are an esthetic, cultural and economically important big game species on the Hualapai Indian Reservation. Resident Desert bighorn sheep populations are located on the rocky cliffs and canyon walls along the northern edge the Hualapai Tribal Lands. Depending on the time of year desert bighorn sheep roam along the flatlands on top of the Southern rim of the Grand Canyon down to the Colorado River. With multiple use management activities on their home range, and big game hunting to generate revenue for the Hualapai Tribe, it is important to conduct annual surveys to determine distribution, overall population size, and sex ratios to maintain and properly manage the resident herd. Survey information for desert bighorn sheep exists from 1981 until present. This survey data varies in time conducted, survey methods and personnel conducting survey.
This video shows a number of Desert Bighorn Sheep found in their natural environment upon the Hualapai Indian Reservation within the Grand Canyon. Helicopter flights are scheduled annually by the Hualapai Department of Natural Resources Wildlife Program to count the number of Bighorn Sheep.
Desert bighorn sheep generally prefer habitat consisting of rocky outcrops, canyon cliffs and the flatlands above these cliffs. Abundant feed in the form of annual grasses, small shrubs and forbes in close proximity to a water source is an important habitat factor. Rock shelves, wind-cut caves and pockets among the boulders of talus slopes provide cover for the Desert bighorn sheep. On this survey observers looked in all these areas with special emphasis on the sheep trails where the talus slopes and cliff walls meet.
The Desert bighorn sheep seen during annual surveys are classified as lambs, ewes, yearlings or rams. Yearlings are classified as either male or female. The rams are broken into four classes: Class I, II, III, IV. A class I ram is characterized by having mass at the bases of the horns only and horns appearing triangular from the front and are widespread. A class II ram has mass at the 1/4 curl point and have a “sickle-horn” appearance. A class III ram has mass at the ½ curl point with the horn reaching a 3/4 curl plus. A class IV ram has mass at the 3/4 curl point with the horns appearing squarish and having a tight curl. Class IV rams usually have a curl larger than 3/4 approaching a full curl with extensive “brooming” at the horn tips. Regulation rams are characterized as class III and IV only. These individuals are considered trophy animals and are hunted on a yearly basis. Non-regulation rams are characterized as class I and II and yearling rams. These individuals are not harvested.
A total of 232 desert bighorn sheep were seen and classified during the 2002 surveys. The population survey consisted of 28 regulation rams, 37 non-regulation rams, 128 ewes (includes 4 yearling ewes), and 21 lambs.
One of the most critical habitat requirements is water. The Wildlife Program's management activities includes providing supplemental water in habitats where water is limited or redesigning water sources to increase its availability to wildlife.
During periods of prolonged drought surface water sources and their impounded runoffs can become hard to find. As part of the Hualapai Tribe's drought mitigation plan, the Wildlife Program has established a number of rain water catchments in remote areas of the canyon to provide water for wildlife.
Desert Bighorn Sheep "Banding" on the cliffs located on tribal lands
To view other areas of Bighorn Sheep "Banding" on the Hualapai Reservation
Please go ahead and (click here) for pictures of Mohawk and National Canyon