Tuesday, January 6, 2009

Sheep Capture, Part 1: Overview

During the first weekend of January 2009 members of Montana Fish, Wildlife & Parks, Utah Division of Wildlife Resources, and a crew from Pathfinder Helicopters of Salt Lake City captured 60 bighorn sheep near Sun River Canyon. While this wasn’t something new--Montana has been translocating bighorns since before 1941—the science behind managing bighorn sheep is unique.

As the sun rises on Saturday, 3 January 2008, the temperature is about -28 F. This view is taken looking east of Montana's Rocky Mountain Front on the Benchmark/Willow-Beaver Creek Road southwest of Augusta. Mountain on the right is Haystack Butte.

As one of Montana’s Rocky Mountain bighorn sheep nimbly hops from crag to crag or casually grazes on a rocky ledge in frigid weather it is easy to believe them hard, sturdy animals.
In their own right, they are. However, like many of God’s creatures they are at the mercy of humans.

Some experts believe that bison were the only animal in the United States to outnumber bighorn sheep before Lewis & Clark and the subsequent settlement of the west. Diseases and unlimited hunting decimated wild sheep in North America. Domestic sheep carried diseases that affected wild sheep much like human diseases ravages Native Americans.

Bighorn numbers were so low in Montana that legal hunting of the species was closed from 1915 until 1953. A few sheep were brought from out of state to start new herds. Twelve sheep from Banff, Alberta were released at the Moiese Bison Range in 1922, and 16 sheep from Colorado were released in the Missouri Breaks in 1947.

Even with these measures, Montana’s bighorn numbers remained small. Montana Fish, Wildlife & Parks estimated that there were only 1200 bighorns in Montana in 1950.

Since then wildlife managers have worked to grow Montana’s bighorn population. There were about 4800 by 1997. That is the good news. The not so good news is that crowded herds can damage habitat and allow diseases to race through a herd quickly. During a trapping operation in the Sun River area in January 2005, Quentin Kujala, Management Bureau Chief, FWP Wildlife Division, (then area biologist) and Graham Taylor, Region 4 Acting Regional Supervisor agreed that having sheep numbers above target was “spooky.” Each voiced their opinion that being under target and working toward it was easier than keeping a population at target and healthy.

In January 2008, current area biologist Brent Lonner said there is a minimum of 900 sheep in the Sun River area. He said that FWP’s goal is to stay within 10 percent of their target of 775 head for the Sun River complex. That would translate into a herd of 852 sheep.

To reach that target FWP uses both hunting and translocating sheep to locations both in and out of the state. Lonner said that he has taken a wide range of comments concerning translocating Montana bighorns. Some believe it is a good program, some don’t care to have Montana sheep taken from the state, and still others wonder why objectives can’t be met by allowing more hunting.

Locations for sheep taken out of Montana are sought only after FWP finds no areas that need sheep within the state, Lonner said. He added that Montana only pays for some manpower and a few tests when sheep are moved to other states. All other trapping and translocating costs are born by the receiving states. It cost about $900-$1000 per sheep to capture, do testing and blood work. That was paid for State of Utah with funds provided by the Federation of North American Wild Sheep. Additional cost for manpower, radio collars, per diem and truck costs were born by Utah.

Kujala addressed the reason for not allowing more hunting best when he said that if 30 more ewe permits were issues for two of the areas within the Sun River complex, hunters would focus on a specific piece of ground and harvest sheep in the most accessible areas. In contrast, he said that by capturing a few animals over a wide area sheep herds continue to habitat areas were sheep currently live. He and most wildlife biologist contend that sheep are not pioneers--like whitetail or elk. Bighorns avoid dispersion and once eliminated from a specific area tend to not return of their own volition.

Since sheep that have been extirpated from areas won't recolonize, and other areas have an excess of sheep, which may destroy habitat or pose a disease risk to their own herd, managers believe tranlocating sheep is essential.  Kujala said, "Translocating is prescribed, almost necessary in sheep managment."

The 60 sheep that were captured in the Sun River area this winter were released to Utah's Uitna Mountains.  Randall Thacker, a biologist for Utah's Division of Wildlife Resources, said, "All the sheep were released Monday (5 January), and they look great."

Links to this post:

Sheep Capture, Part 1: Overview

Sheep Capture, Part 2: Net Gunning

Sheep Capture, Part 3: Processing

Sheep Capture, Part 4: THERE IS NO PART 4

Sheep Capture, Part 5: Past and Future

No comments: