Adopt A Bighorn Program
Junior Biologists' Report 2002
This year I was given an awesome opportunity to assist the National Bighorn Sheep Interpretive Center in the Adopt-A-Bighorn project. I took an Environmental Science class that allowed me to have this opportunity. I began helping with this project in November 2001.
Yellow 38, better known as Y-38, the ewe that the National Bighorn Sheep Center adopted, was collared in May 2001. She was collared with a yellow GPS (Global Positioning System) collar. GPS is a satellite navigation system that provides specially coded satellite signals that can be processed in a GPS receiver on the ewe. The receiver can compute positions in time (there is a receiver clock on the collar) and space (in three dimensions on a north/south axis, east/west axis, and height above sea level). This GPS collar recorded where she went from May to December by receiving satellite signals. In December, the Wyoming Game and Fish Biologists, John Mioncznski used an electronic devise to make the collar fall off without hurting Y-38.
All of the recorded information was downloaded to a floppy disk in the program Excel. This information had the following categories: year, day, hour, minuet, second, Easting, Northing, zone, altitude, and temperature (in Celsius). All positional information was in UTM (Universal Transverse Mercator) format. I didn't know what it all meant, so I asked around and found out that UTM is a format used on typographical maps to find out where a point is located on the map. This is so there are simple numbers to make plotting precise locations easier than using the complex degrees, minutes, and seconds of latitude and longitude. Learn more here and here. "Eastings" are coordinates telling how far east in the zone the point is and are referenced to the centerline of the zone known as the central meridian. "Northing" coordinates that tell how far north the point is in the zone (here). Line up the Northings and Eastings coordinates till they meet, then a point can be located on a map. "Zone" is the area where the information was taken (here. Zone 12 is the zone where Y-38 and the other Whiskey Mountain Bighorn sheep herd live. "Altitude" is how high from sea level the point is located. After I knew what all the numbers meant and how to use them with a typographical map, I started to map out where Y-38 was from May to December. There were many pages of information and I just wanted an overview of where Y-38 went, so I only mapped out her location every third day.
I found out that she moved around the territory a lot. She wasn't one to just stay in one place all summer or winter. She would migrate around the mountain, but her main hang out was on Whiskey Mountain. This mountain is the fall and winter (September and December) range for the Whiskey Mountain Bighorn Sheep heard. Some of the winter days she would migrate to the winter range, just 8 miles out of Dubois, which is called Trail Lake area. There are natural mineral licks in that area. These mineral licks give bighorn sheep nutrients that they need to survive like, selenium. Selenium is an essential nutrient in order for the bighorn sheep to survive. Without this nutrient many lambs get sick with such symptoms as a stiff-legged gate and eventually die. After she was at the winter range for a few days she would go back up Whiskey Mountain.
It was a neat experience for me to find out where Y-38 went. I learned that Whiskey Mountain and Middle Mountain were indeed where the Bighorn sheep are in the summer. I plan to continue with this project by helping make an educated guess of why Y-38 went where she went. I will start doing this by comparing where the salt blocks are to where she went. John Mioncznski placed the salt blocks on Middle and Whiskey Mountain to help give the bighorn sheep the selenium that the need to survive.
If you come to the National Bighorn Sheep Center, in Dubois Wyoming, you can see the map I plotted of Y-38's journey from May to December.
By,
Melissa Glenn
Interview with Forest Service Wildlife Biologist Mark Hinschberger
Mark Hinscberger is a member of the Whiskey Mountain Bighorn Sheep Technical Committee and past president of the National Bighorn Sheep Interpretive Association. His knowledge and dedication to wildlife come across loud and clear when you meet him. We hope you will enjoy this opportunity to "meet" him in this brief interview.
What does the Forest Service do that involves the bighorns?
National Forest System lands managed by the Forest Service provide habitat for all most all of the Rocky Mountain Bighorn sheep in the Nation. The Forest Service also manages habitat for Dall sheep on the Chugach National Forest in Alaska.
2. What do you do to help the habitat of the Rocky Mountain bighorn sheep?
As a member of the Whiskey Mountain Bighorn Sheep Technical Committee, I am involved in the management of this population of Rocky Mountain bighorn sheep. That involvement includes planning and conducting habitat improvement projects for bighorns. Those habitat improvement projects have included prescribe burning and mechanical treatments of timber stands to increase forage and re-establish migration corridors for sheep, herbicide treatments to reduce mat-forming forbs and increase grasses for sheep, and fertilization treatments to improve vegetation production and vigor on sheep winter ranges.
3. Is bighorn sheep habitat affect by weather?
Short answer: Yes. Drought conditions that occur occasionally reduce vegetative production and thus the amount of herbaceous vegetation available to foraging bighorns is reduced. During these times the vegetation that is produced can be over utilized and the plant species composition or vigor can change, affecting future vegetative conditions in these important sheep ranges. It appears that drought or very wet years with increased deposition of pollution such as nitrates in high elevations may affect availability of some trace minerals in the soils, such as selenium, to plant uptake and thus the sheep's ability to acquire these important nutrients in their diet. Also, large snow storms can cover vegetation on the winter range that makes winter forage not readily available for periods of time. During the winter of 1990/91 extreme winter weather conditions of unusually deep snow, severe cold temperatures, and very strong winds for an extended period of time was indirectly responsible for an all age pneumonia die-off that reduce the Whiskey Mountain herd by about 300 to 400 animals.
4. Do forest fires affect the bighorn sheep?
Generally forest fires have no direct effects to bighorn sheep. They are mobile and quick and can get out of the way of forest fires. Wildfire and prescribed fire in winter range areas after the vegetative growth (summer, fall or winter) can indirectly affect sheep by limiting available forage during the critical period - winter. Forest fires have greatest impact for bighorns in a beneficial way. They can open up areas by removing timber in historic migration corridors. This allows sheep to access ranges during travel with reduced susceptibility to predation. It also increases usable forage in these areas. Easier access/migration to larger sheep habitat areas with improved habitats (vegetation) can reduce mortality and sustain larger and healthier sheep populations. Fire can enlarge foraging areas that have been lost due to fire suppression since the settlement and fire suppression activities of European man. Fires can also improve existing vegetative communities by improving plant composition, vigor, and health.
5. What inspired you to become a wildlife biologist?
My love of the outdoors and interest in biology and sciences in high school inspired me to continue my education in college in natural resources field. I got involved in a work-study program early in college working with graduate students on some wildlife research projects and was "hooked".
6. What was your first experience with bighorns and was it exciting?
I helped with a bighorn sheep transplant on the Bridger-Teton National Forest in the Wyoming Range west of Big Piney, Wyoming in 1981. These sheep came from the Whiskey Mountain bighorn sheep population. Watching 35 sheep being released into their new home was very exciting and gratifying to re-establish bighorn sheep into their historic range.
7. Do you have any advice for our readers who would like to become wildlife biologists and work with bighorns?
I suggest that you study and work hard to acquire knowledge in school. Get involved in as many projects that provide you with the experience, knowledge, and skills that employers are looking for in applicants. Don't avoid the English, speech, creative writing, psychology, sociology, and other humanity classes while in school, because wildlife management in our society involves more than just managing wildlife, populations, and habitats. It involves a lot of oral and written communication and people skills.
Bighorn FAQs: We Have More Answers
Q.
Where are the Whiskey Mountain Bighorn sheep?
A. The Whiskey Mountain Bighorn sheep herd lives on the Whiskey Mountain by Dubois, Wyoming. It is just 8 miles southeast of town. However, the sheep migrate from the top of Whiskey Mountain and around Middle Mountain (the summer range) to their winter range down the mountain in the trail lake area (winter and fall range). The bighorn sheep migrate from one range to another.
Q. When is the best time of year to go see the bighorn sheep?
A. In Dubois, Wyoming it is best to come see the sheep in the winter because they are in there winter range and that is closer to the trail lake road where you can drive up an see them. It is also not as far of a hike to see them, we also have winter tours that we take people on to go see the bighorn sheep. In the summer they are so far up that it would be a day or two hikes to go see them. Call the National Bighorn Sheep center if you are interested in coming to Dubois, Wyoming to see the Whiskey Mountain Bighorn Sheep.
Q. Do bighorn sheep migrate?
A. Yes, they have different ranges that they go to throughout the year. In the winter they are on Torrey Rim, BLM Ridge, Sheep Ridge, and occasionally the get down into the Torrey Creek Valley near Trail Lake. During the spring, ewes are in lambing areas between winter and summer range. In the summer, sheep move up even higher into the mountains such as Middle and Arrow Mountain. In the fall they return to slightly lower elevations like Whiskey Mountain.
Q. Does the Whiskey Mountain Bighorn sheep herd come right into town?
A. No; however they are just 8 miles out of town and you can drive to the winter range. Dubois residents can look out their windows with spotting scopes or binoculars and see them. They aren't right in town, but they are so close they are seen often.
Q. 1. Can you pet the Whiskey Mountain Bighorn sheep?
A. No, the Whiskey Mountain Bighorn sheep are wild animals. They don't like to be too close to people. You can see them but it is not a good idea to feed or touch the bighorn sheep. Getting too close to the bighorn sheep frighten them. It is not good for the sheep or for the people to touch the bighorn sheep.
Q. Is the Whiskey Mountain Bighorn sheep herd still one of the largest?
A. Yes, many bighorn sheep were dying off but biologist have been working hard on trying to save the bighorn sheep. There were around 800 sheep counted last year and we are hoping that the numbers stay high without over population. Right now they are doing ok.
Q. Why do bighorn sheep bang heads?
A. They bang heads to show dominance, and to fight for a ewe. The clashing of heads comes mostly during the rut. The clashing determines a dominance order and the higher-ranking rams get to do most of the breeding.
Q. When to Rocky Mountain bighorn sheep have their rut and what is it?
A. The rut is the breeding season for the bighorn sheep. The rut is usually in November and extends to January. The Rams will fight for dominance by clashing their heads. The clashing determines the dominance order and the higher-ranking rams can do the most breeding. The bighorn sheep have a gestation period of 6 months and give birth to one lamb every year.
Q. How big are Rocky Mountain Bighorn Sheep?
A. The Adult Rocky Mountain bighorns averagely weigh around 125-275 lbs and some rams weigh up to 300 lbs. The ewes typically weigh 75-150 lbs. Rocky Mountain Bighorns can grow to a height of 2.5-3.5 feet. The length of the Bighorn Sheep including the tail is about 5.5-6 feet.
Q. When is lambing season for the Rocky Mountain Bighorn Sheep?
A. The lambing season mostly occurs in late-May through mid-June. Before the ewes give birth they will isolate themselves in rocky areas. The lambs when they are newborns typically weigh from 8 to 10 lbs. Lambs are able to walk within hours after they were born. The steep terrain where the ewes have their lambs is to help protect themselves from the predators. Lambs stay with the ewes for the first year of the lamb's life so ewes can teach them their home range and how to behave and survive.
Q. How can you tell the difference between the Stone sheep and the Rocky Mountain Bighorn sheep?
A. A Rocky Mountain Bighorn sheep is a "bighorn" and a Stone Sheep is a "thinhorn" the bighorns (Rocky Mountain Bighorn, Desert Bighorn, California Bighorn) horns make a simple circle (full curl), half circle, or smaller (banana horn). The thinhorn's (Stone's Sheep, Dall's Sheep) horns are generally smaller in diameter than the "bighorns" and they spiral and twist outward so they usually escape breaking or broom off the tips in dominance fights. Stone sheep are a contrasting, and often have a dark gray and white coloration in their fur.
Our Adopted Ewe:
The Travels of the Ewe with Yellow Collar 38 from May to December
In May 2001, biologists from the Wyoming Game and Fish Department, Bureau of Land Management, and the Forest Service attached a yellow collar around the neck of a Rocky Mountain bighorn ewe on Torrey Rim near Trail Lake Road just south and east of Dubois. In addition to the big plastic collar with the black number 38, the collar had a global positioning unit attached to it. Four times a day the collar sent [radioed] a message to a satellite and the satellite sent back the coordinates to the collar.
In December when the collar was removed, it contained a record of where this ewe had traveled for the eight months she wore the collar.
The National Bighorn Sheep Center's Junior Biologist Melissa Glenn of Dubois used the recorded data from Y38's collar to plot the points on this map.
Melissa took the coordinates from the collar's record every three days, marked the points on the US Geological Service Topographical Maps, and then drew a line between the points.
Each color represents a different month. Notice that in July, Y38 was very high in the Wind River Mountains near the Continental Divide.
With modern technology we can track one bighorn ewe on her seasonal migrations up into the Wind River Mountains during the summer following the melting snows looking for the best grazing. In the fall and winter months, the open wind-swept slopes of Whiskey Mountain became her preferred habitat. "As the crow flies" this ewe's range is just over 14 miles, but the GPS data reveals a tremendous movement within this range.
