Hi, I’m Holly Strand of Stokes Nature Center in beautiful Logan Canyon.
Bighorn sheep used to be quite common in UT. They were a frequent subject of pictographs and petroglyphs indicating their importance to prehistoric people. In 1776 Father Escalante a Spanish Franciscan missionary-explorer, wrote about a site near the Colorado river in Utah “here wild sheep live in such abundance that their tracks are like those of great herds of domestic sheep.”
While not so common today, you can still see two subspecies of bighorn in Utah: Rocky Mountain bighorn and the desert bighorn. In 1997 twenty three California bighorn sheep were transplanted to
Antelope Island. Formerly thought to be a subspecies, the California bighorn is now usually considered to be a separate population not a subspecies of Rocky mountain bighorn sheep.
So what’s the difference between the Rocky Mountain and the desert bighorn sheep ? Rocky Mountain bighorns are noticeably larger–about 1/3 again the size of the desert bighorn. Not surprisingly, the desert bighorn is better adapted to arid environments. It can go several days without drinking free water and lose up to 10% of its body weight in water. Then it can make up for it in a single drinking spree. Since drinking sources are limited in deserts, a significant portion of water intake comes from plants. Prickly pear, pincushion and barrel cactus are often necessary parts of their diet. Rutting season for the desert bighorn lasts from July to December while the Rocky Mountain bighorn sheep is generally limited to November and December.
The geographic boundary between the 2 subspecies is hard to define but in general you can use I 70 as a rough dividing line.
By the 1960’s Utah had almost lost most of its bighorn populations due to overhunting, habitat loss and competition with domestic sheep. Now, thanks to transplants from WY, CO, NV and Canada, we have 800 sheep in 6 areas in the northern half of the state. There are 2800 desert bighorn found in a large number of sites in southeast Utah. Some of them are even the original Utah herds rather than transplants.
All bighorn are known for their surefootedness, remarkable eyesight, and preference for canyons, gulches, talus cliffs, steep slopes, and mountain tops. Look for them within 200 meters from “escape terrain” or landforms that are too rugged for both human and non-human predator.
On November 14-15, Friday and Saturday of this week, the Utah Division of Wildlife sponsors its annual Bighorn Sheep festival. Bring your binoculars to see rams running headlong into each other and bashing their heads in an attempt to win females. For a link to more information about this festival see wildaboututah.org
Thanks to the Rocky Mountain Power Foundation for supporting research and development of Wild About Utah topics.
For Wild About Utah and Stokes Nature Center I’m Holly Strand.
Photo: Courtesy Utah Division of Wildlife Resources, Photo by Brent Stettler, http://wildlife.utah.gov/news/08-10/bighorn_festival.php
Text: Stokes Nature Center: Holly Strand
Sources & Additional Reading:
Bill Bates, Utah Division of Wildlife Resources, personal communication November 10, 2008)
Utah Division of Wildlife Resources. 1999-2005 Statewide Management Plan for Bighorn Sheep. http://wildlife.utah.gov/hunting/biggame/pdf/bighorn_plan.pdf
Valdez, Raul, and Paul Krausman eds., 1999. Mountain Sheep of America. Tucson: University of Arizona Press
For more information on the bighorn sheep festival see: