Workshop introduces participants to the habits, struggles and beauty of magnificent mountain animals

By Ann Haver-Allen, Earth Odyssey Editor

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I have long thought bighorn sheep were especially magnificent animals.  I hoped against hope that one day I would spot at least one of these beautiful animals while out hiking.  But that never happened, even though I have hiked through their territories numerous times.

I’m not sure where my fascination with these mountain dwellers originated, but I have always found them intriguing. Perhaps it’s because I’m an Aries and the ram rules my sign. Maybe it’s that I admire an animal who can survive and thrive in areas that appear desolate.

Who can’t admire an animal that is able to snack on a barrel cactus—just lean over and take a bite right out of the cactus?  Whatever the reason, for years, I have longed to see bighorn sheep in the wild.  Imagine my delight when I learned that the Arizona Game and Fish Department would be holding a Bighorn Sheep Workshop that included an evening’s lecture and a field trip the following day.

Literature cautioned that sightings were not guaranteed, but were probable. As far as I was concerned, probable increased my odds dramatically, so I promptly signed up.  I was not disappointed. On our field trip, we spotted about 50 bighorn sheep.

We saw rams butting heads, rams chasing each other, ewes ignoring rams, sheep snacking on mesquite bushes and barrel cacti and many, many other wonderful, memorable sights.

But most importantly, we learned about bighorn sheep—their habitat and the challenges they face as they struggle to survive.

“These workshops offer wildlife enthusiasts an opportunity to learn about the sure-footed desert bighorn sheep and view them in their native habitat,” said Zenon Mocarski, information and education program manager for the Game and Fish Kingman office. “You can’t begin to appreciate these animals until you’ve seen them in the wild.”

About bighorn sheep

The number of bighorn sheep in North America in pristine times is unknown, but pre-Columbian numbers of all subspecies has been estimated at 1.5 to 2 million. Three subspecies of bighorn sheep exist under the species umbrella.

Bighorn sheep live in separate male and female groups and only come together during breeding season.

The subspecies, desert bighorn sheep (Ovis canadensis nelsoni), is named in commemoration of American naturalist Edward William Nelson (1855-1934). Populations of the desert bighorn sheep declined drastically with European colonization of the American Southwest, primarily between 1860 and 1920.

Exposure to livestock-borne parasites and diseases nearly decimated the bighorn sheep, which lack resistance to the pathogens carried by domesticated animals.

Even conjunctivitis, commonly known as pinkeye, can be deadly to bighorn sheep that depend on their eyesight for survival. Bighorn sheep can see other animals up to a mile away. They can run 30 miles per hour on level ground and 15 miles per hour when climbing. Imagine being blind and running up a mountainside at 15 miles per hour and you get the idea of how deadly this combination can be.

By 1960, the overall bighorn sheep population in the United States, including desert bighorns, had dwindled to 15,000 to 18,000.  Today, Arizona’s Black Mountains contain the largest contiguous desert bighorn sheep population in the world and is the primary transplant source of the nelsoni subspecies.

A 1998 survey found 1,800 desert bighorn sheep living in the Black Mountains—about one-third of the state’s total population.  But at the beginning of this decade a combination of factors—drought, disease and predation—reduced the herd to only about 600 to 800.

“We believe drought and disease have run their course,” said Jeff Pebworth, wildlife program manager in Kingman. “The herd needs time to recover, however.”

Bighorn sheep have a slow rate of population growth, which means their ability to recover from a die-out is slower than that other species.

Mocarski said predators are not the enemy “When you’ve got 1,800 animals running around, lions are not an issue,” Mocarski said. “When you cut the number of animals down to 600, now you’ve got a problem. Lions need a big kill a week. After the negative impacts of disease and draught, predation can be a real problem.

“We have seen a small rebound and stabilization of the population,” Mocarski continued. “This is an animal worth saving and we have to do whatever we have to do to save these animals.”

Males

Males are called rams and are most noted for their head-butting behavior during mating season.  Rams generally begin mating at about 4 years of age and will charge each other at up to 20 miles per hour. This head-butting behavior determines dominance.

The horns have space (or sinuses) that reduces the weight while maintaining strength.  A ram’s horns and head can weigh as much as 30 pounds.

The age of a ram can be determined by counting the rings on his horns, which continue to grow throughout his life. An adult ram’s horns may measure up to 40 inches along the outside curl with a basal circumference between 13 and 16 inches. If horns begin to impede vision, rams will shave, or broom, the ends.

Rams weigh from 150 pounds to 220 pounds, although the average is 170 to 175 pounds. They stand 3 to 31/2 feet tall and measure 4 to 41/2 feet from head to tail.

Females

Females are called ewes. The biggest visual difference between rams and ewes is the horns. Ewe horns are generally 10 to 13 inches long with a circumference of 3 to 6 inches. A ewe’s age cannot be determined by her horns, which do not grow throughout life.

Ewes generally begin mating at 2 years of age. Mating season is July through December.  Ewes are about half the weight of a ram—90 to 120 pounds.

Babies

Babies are called lambs. The gestation period is about six months with lambs generally born in winter. Multiple births are extremely uncommon.  Newborns weigh 8 to 10 pounds and are active within minutes of birth.  Lambs are very susceptible to predation by golden eagles, bobcats, coyotes and mountain lions. Only about one-third survive to adulthood.

Lambs have dark eyes and fuzzy, dark-gray hair. As they mature, their eyes lighten to the characteristic amber color. Horns begin to grow about two months after birth. Within a few months, the coat

mimics that of the adults—buff to chocolate-brown with a white muzzle and a white rump patch.  Lambs stay with their mothers for about two years, at which time they will join either a ram or ewe herd.

Bighorn sheep facts

Can live 10 to 12 years, but may live as long as 17 years. Usually one lamb is born, but only about one-third survive to adulthood.  Juveniles stay with their mother for about two years.

•  Live in areas too dry for many predators.

•  Mountain lions are the primary predator of adult bighorn sheep. Coyotes and golden eagles prey on lambs.

•  Can lose up to 30 percent of their body weight and survive. Desert bighorns can go extended periods without water and quickly recover from dehydration

•  Can drink more than four gallons of water in two minutes.

•  Have a nine-stage digestive process to obtain maximum nutrition from the desert plants they eat.

•  Hooves are designed for mountain climbing: hard on the edges and spongy inside, which creates a suction grip.

•  Can see up to a mile away—equivalent to 8-powered binoculars.

For more information about Desert Bighorn Sheep, see www.azgfd.gov/.