Thinning the herd

Tuesday, Oct. 11, 2005 | 9:13 a.m.

Nevada Wildlife Division officials are re-evaluating how they should monitor man-made water sources in the wilderness after learning a valve to a water tank in the area where 22 desert bighorn sheep died in July was turned off when it should have been on. Read about it online at lasvegassun.com.

Some of the desert bighorn sheep that descend daily from River Mountain to drink water and graze at Boulder City's Hemenway Park will be making that trek for the last time later this month.

Nevada's Wildlife Division plans to move about two dozen of that herd's ewes and lambs to the Virgin Mountains near Mesquite, biologist Patrick Cummings said.

"We want to assure the people of Boulder City who enjoy watching the bighorn sheep that we are not taking all of them away -- we're just thinning the herd," which currently numbers about 200, Cummings said. "The 50 to 60 sheep a day that currently come down to that park are not desirable from a management standpoint."

The operation, tentatively set for Oct. 22, will involve firing a 10-by-10-foot net from a Hughes 500 helicopter to capture one animal at a time.

"If it is done properly, it is much less stressful than darting the animals," said Jim Pope of Leading Edge Aviation of Lewiston, Idaho, which conducts 100 to 200 operations a year to capture various animal species for research or relocation.

"We are capable of doing darting captures, but we prefer the net gun because no drugs are used. It's safer for the animal. The animal's safety is our top priority."

State wildlife workers and volunteers will chase the sheep from the park up the mountain, where the helicopter will be waiting for them, hovering above flatter ground.

Pope said the helicopter will fly low to the rocky surface so that one of his five crew members -- a certified net-gunner -- can discharge his pneumatic weapon from within 15 to 20 feet of the targeted animal.

"Firing at that close distance is safest for the animal," Pope said.

After the net is fired, the helicopter is lowered to within inches of the ground so animal handlers can jump off and blindfold the sheep to calm it down, Pope said.

Leather hobblers are then attached to the animal's legs, and the sheep is placed in a customized bag that allows it to be moved in an upright position as it hangs from a cable extended from the helicopter's belly.

"The animal is gently lifted and gently lowered to the ground on its feet at the base camp," Pope said.

The animals are examined by a team veterinarian who draws blood for tests to determine if the animal is healthy, Pope said. Some animals also are fitted with tracking collars to monitor them in their new environment.

That part of the operation will cost $15,000, which will be paid for by a donation from the Fraternity of the Desert Bighorn, a local sportsman's group, wildlife spokesman Geoff Schneider said.

The Las Vegas-based organization also will pay the estimated $7,000 to move the animals in eight crates to their new home east of Mesquite, Schneider said.

Wildlife officials insist the move is not to benefit hunters. Hunting of bighorns is allowed in the Virgin Mountains, but not in the River Mountains.

It's a nonissue because "there are so few hunting tags issued statewide for bighorn sheep," Schneider said. Just two resident tags have been issued to hunt bighorn rams in the Virgin Mountains during the upcoming hunting season Nov. 12-Dec. 11. No nonresident tags were issued.

Male lambs that will be moved this month won't be targeted. They won't be hunted until they reach adulthood, Schneider said. No tags are issued to hunt ewes.

This season 125 resident tags, each costing $120, and 19 nonresidential tags, each costing $1,200, will be issued to hunt mature bighorn rams at 20 locations throughout the state.

There are between 5,000 and 5,500 bighorn sheep statewide, officials said. The bighorn is Nevada's state mammal.

Cummings said the Virgin Mountains herd currently numbers about 70, and eight rams have been seen in that herd.

A new water system has been installed in the area where the captured sheep will be taken.

As uncomfortable as the relocation procedure might sound, environmentalists say such operations are necessary.

"It's prudent for the animals' safety," said Jane Feldman of the local Sierra Club.

Feldman said the Clark County Habitat Conservation Plan, which her organization helped implement, allows for moving sheep to appropriate habitats.

Relocation operations "raise the interesting problem of how urbanization is encroaching on the animal's habitat," she said.

"Hemenway Park is a lovely place, and the sheep love to be there -- they are drawn to it. You have competing claims of man and animal. Something has to be done to address what is best for both."

Since the late 1980s, bighorn sheep from the River Mountain herd have made daily treks to Hemenway Park, especially during the summer months.

The sheep not only have become popular with residents, many of whom provide them food and water, but also are viewed daily by hundreds of tourists from Hoover Dam tour buses that take detours to the park to see them.

Cummings said the bighorns that are moved "will have far less contact with humans and other urban dangers such as being killed by vehicles and harassed by domestic dogs."

Ed Koch can be reached at 259-4090 or at koch@lasvegassun.com.