Several dozen bighorn sheep west of Great Falls likely will be trapped this winter and sent to Utah as Montana officials try to deal with a population surplus, and Utah officials try to build their state's sheep numbers.

Montana wildlife commissioners Thursday supported a plan to trap about 60 bighorn sheep in January, using nets deployed from helicopters, then send them to Utah.

States often ask Montana about availability of wildlife for transplanting, and sheep are among the species that have been relocated previously.

Sheep populations west of Great Falls are too large, said Quentin Kujala, a wildlife manager for the Department of Fish, Wildlife and Parks. That raises concern about competition for food, the health of sheep and their eventual susceptibility to disease.

Sheep numbers ''ebb and flow with habitat conditions, with climate conditions,'' Kujala said. Population targets are based on what the land can support, he said. In two wildlife management districts that lie in the Sun River area west of Great Falls, the goal is for each to have 200 wild sheep that are observed from the ground or the air, Kujala said. The observed population in each district is approaching 300, he said.

About 5,800 bighorn sheep in 48 distinct populations inhabit Montana, according to the Web site maintained by Fish, Wildlife and Parks.

Wildlife officials do not wish to transplant Sun River sheep within Montana at this time.

There are some potential ''receiving'' sites but they must be studied to determine, among other things, their proximity to private land, access by hunters and proximity to domestic sheep. The risk of wild sheep becoming sick rises when domestic sheep are close by, Kujala said.

He also said that increasing the hunting quota for wild sheep to lower the Sun River population is not a sound option, because hunters' removal of the animals would not be sufficiently dispersed. To best manage the population, sheep should be removed from a mix of locations within the Sun River area, Kujala said.

Helicopter removal involves flying the sheep out either aboard the chopper or in a sling below it, after nets trap them.

Sheep received from Montana would be released in a northeastern Utah area that has no wild sheep, Kent Hersey of the Utah Division of Wildlife Resources said in a telephone interview Thursday. Utah has received animals from other states previously and has found transplant projects largely successful, Hersey said. Getting 60 this winter is an attractive prospect, he said.

''Once you get above 50 you have a lot of sheep out there and you can get some reproduction and start growing the population,'' Hersey said.

The Foundation for North American Wild Sheep supports sending 60 animals to Utah, a representative of the sheep advocacy group told the Montana Fish, Wildlife and Parks Commission.