It takes more than a second before he reluctantly turns toward the humming of cars on the adjacent Interstate 680 and scrutinizes the explosion of commercial and residential development that has drastically transformed the serene open space of his childhood into the bustling urban center of the Tri-Valley.

"All of this is new in my lifetime," Koopmann said of the growth in Dublin, Pleasanton and Livermore. "It makes me appreciate my property even more ... all the blood, sweat and tears that have gone into this ranch." Koopmann, 55, is proud and protective of his not-so-little piece of rural heaven that today is penned in by the freeway, mega-mansions and an 18-hole municipal golf course.

And, like a death-row inmate who receives the governor's pardon at the eleventh hour, Koopmann's appreciation is tangible when he talks of how he deftly averted a possible forced sale of the ranch in the late 1990s.

By working in cooperation with local, state and federal officials, Koopmann has successfully established wildlife habitat easements on his 853-acre ranch, protecting the threatened California tiger salamanders, red-legged frog and the threatened California rancher.

This third-generation rancher has been honored with numerous awards recognizing his conservation efforts and for sharing his insights as a board member of the California Rangeland Trust and member of the California Cattlemen's Association. He tells his story to caution other ranchers to plan ahead to ward off the crippling effects of estate taxes.

"One of the toughest things is to go to your parents and say 'You're going to die someday. Can we sit down and talk about it?'" Koopmann said.

He and his father Herman Jr. were in the process of forming a family trust when Herman Jr. suddenly died in 1991 of a heart attack. Three years later, Koopmann's mother Tillyann died, and he found himself staring down a

$750,000 estate tax bill.

Koopmann's options were to sell off the entire ranch or subdivide and sell off 100-acre parcels to developers, who would have built "McMansions," referring to the large homes now dotting the hillside. He opted for conservation easements instead and was able to preserve the ranch and land.

"It's a way of life and a heritage that is really rich to us," Koopmann said of ranching.

While some of the more old-school ranchers would be loathe to work with environmental groups or regulatory agencies, Koopmann embraces this with enthusiasm.

On a recent tour of the ranch, Koopmann steered his extended-cab pickup over a hill while proudly pointing to the solar-powered pumps scattered on the property that draw water from a spring, bringing water to areas it hadn't before. The project, partially funded by a federal program, has helped reduce the destruction of riparian habitat, as cattle there no longer have to tromp through the creeks.

Halfway up a steep hillside, Koopmann points to a pond that serves as habitat for the endangered California tiger salamander. Ponderosa Homes paid him to establish a permanent easement preserving the 31-acre area around the pond.

To help broker that first easement deal, Koopmann turned to California Rangeland Trust, a Sacramento-based group governed entirely by ranchers, including Koopmann, who sits on the board of directors. The group, founded in 1998, works closely with ranchers to conserve open space and natural habitat provided by California's ranches.

"We're losing rangeland that provide habitat value at an astounding rate, especially in the Bay Area," said Koopmann.

In 2005, he also inked a conservation easement with the city of Pleasanton for 107 acres that serves as replacement for wildlife habitat destroyed when the Callippe Preserve Golf Course was developed. Koopmann received a little more than $1 million for the easement, which was placed permanently under the CRT's care.

Koopmann is close to signing a lease with the city to graze his cattle on a portion of open space near the golf course.

"This will helps us protect water quality and create the right habitat for the Callippe silverspot butterfly," Assistant City Attorney Larissa Seto said. "They need the local grasses grazed down to a specific level."

Koopmann's creative use of conservation easements to the benefit of the ranch and the surrounding community has earned him a reputation as a forward-thinking rancher who talks slowly, thinks quickly and comes by his rough-hewn hands and faded cowboy boots honestly.

But not every farmer or rancher can afford to be as environmentally creative as Koopmann, so groups such as the California Cattlemen's Association and the California Farm Bureau Federation have been fighting for several years to repeal the federal estate tax, arguing the agricultural community has been unfairly impacted.

"Most farmers and ranchers have their assets tied up in the land, unlike others who have assets in stocks and homes," said Jack King, national affairs manager for the California Farm Bureau. "Unlike stock, where you can sell a portion of the stock portfolio to pay the (estate) tax, it's pretty hard to sell off a portion of the land."

Koopmann's father Herman Jr. was forced to do just that when his father Herman Sr. died in 1967. The family sold 300 acres of irrigated pastures in Turlock to pay taxes.

"I vowed that my children will not go through this," Koopmann said.

Clayton Koopmann, 23, a recent University of California, Davis, graduate with a degree in agriculture management and rangeland resources, and his sister Cari Koopmann, 21, studying animal science at California State University, Fresno, both aspire to be the fourth generation of Koopmanns to preside over the family ranch.

"With the urban encroachment, it's been getting difficult to find land," said Clayton Koopmann, who leases 300 acres nearby to ranch his own cattle. "It makes it more important to me that we try and preserve the (family) ranch."

The ranch has been in the family since Tim Koopmann's grandfather and his great-uncle George bought the land for $35 an acre to start a dairy farm. Plans changed, however, when George was killed while hauling firewood out of the canyon and was hit by a train. The Koopmanns have raised cattle on the property ever since.

"We're tied to this land and entrusted to its care. We're here for its betterment," Koopmann said. "We are stewards of the land. We take pride in the variety of wildlife on the property — most folks who are out on the land everyday have a real appreciation and respect for it."