I know what I'm going to get with my tax rebate, if it comes in time: a .458 Winchester Magnum.

According to "Shooter's Bible," the rifle delivers "more than 5,000 pounds of crushing muzzle energy" from its giant bullets. Once I get one of these elephant guns, I'll enter the state's lottery for sandhill cranes; I'll luck out and get one of the licenses, then head for the marshes.Maybe I can bag one of the big gray birds when it's doing its courtship dance - bowing, dropping its wings, hopping up 15 feet into the air.

Can you imagine what would happen when I blast away at one of those spindly suckers? There it is jumping around, wingspan up to seven feet, three or four feet tall - BLAAM! Feathers everywhere! Skinny old legs flying one direction, long neck off somewhere else!

The Utah Wildlife Board has decided to issue 100 permits to kill sandhill cranes during two three-day weekends in September. The board called for applications to be filed this month, and the drawing for permits is set for Aug. 12 at 9 a.m.

Utah's sandhills are migratory birds, flying in from Idaho and Wyoming. The ones that will be hunted are in the Rocky Mountain population of sandhills.

By telephone, I traced that population to its most important nesting area and discovered the sandhills most likely are in trouble again this year.

Gray's Lake near Pocatello, Idaho, is home for the largest single group of the Rocky Mountain population. And its problems are probably typical of those of the whole population, said Stephen Bouffard, a biologist with the U.S. Fish & Wildlife Service's Southeast Idaho Refuge Complex.

"I'm not sure what the production (of sandhill cranes) will be this year, but the last couple of years it's been real low," Bouffard said. "This year's not looking real good either.'

Sandhill chicks depend on insects, while the adults eat insects, grain and amphibians. Unusual frost in the summer has been killing the insects.

"The drought doesn't help any either," he said. Nests are normally built on tufts of vegetation sticking out of the water. But the drought has lowered the water level, opening paths for predators like coyotes, foxes and badgers.

The drought also kills frogs and salamanders, among the adults' food sources.

I admit that in the overall picture, the sandhills' problems the last few years are an aberration. This crane is one of the success stories of wildlife restoration.

They were in danger once, and hunting was stopped back in 1917. But for the past half-century, the population has been coming back.

Conservation officers use sandhills as foster parents for endangered whooping cranes. Whooping crane eggs are taken from nests in Canada, and given to sandhills to incubate. So when the flocks migrate to Utah, they may well include a few of the protected whoopers.

Steve Phillips, information officer with the Utah Division of Wildlife Resources, said the Rocky Mountain sandhill cranes have come back strongly.

In fact, there are too many for the farmers' comfort. The hunt is a "depredation hunt," and will take place only in Rich and Cache counties, where cranes have been eating farmers' grains.

"They're doing some real severe damage to the standing crop," Phillips said. "They love grain and these farmers are just run ragged keeping them out of their fields."

Phillips added, "They are a good table bird. They're good to eat." He said it's easy to tell the difference between the sandhills and the larger whooping crane. Adult whoopers are white and adult sandhills are gray.

The hunt will be monitored, called off if whooping cranes show up, he said.

Whooping cranes aren't that much larger than sandhill cranes - about half a foot to one foot taller at adulthood, with wingspreads about half a foot larger. That's not a great difference.

Immature whooping cranes are reddish while young sandhills are brownish-gray. I contend it's not easy to tell them apart at a distance. And, of course, young whoopers are smaller than adult sandhills.

The sandhills' total population in the Pacific Flyway is estimated at about 18,000. With 100 permits, Phillips said, "we expect a harvest of about 30 birds . . . It's a very small piece of the pie.

"And it is a way to help farmers solve a problem and provide some recreational opportunities for hunters. Part of our mandate by law is to provide hunter opportunity.'

If only 30 birds will be killed, the farmers can expect little relief, if any.

On the other hand, it's crazy to lift a 71-year ban on killing the birds just when production is low because of drought and early frost.

Compared with the small potential benefit to grain growers, the risk of killing one of our endangered whooping cranes is too great.

After all, those who take their livings from the land - in the long run, all of us, - owe something to nature. The satisfaction of blasting one of these lovely and fascinating birds is a perverse indulgence to which our state government should never consent.