ALBUQUERQUE (AP)--The trust that manages the Valles Caldera National Preserve is replacing its grazing program.

The trust on Dec. 16 approved a temporary steer-only grazing program that will replace an existing one that allows ranchers to graze their cow-calf pairs in the preserve while they rehabilitate their own drought-stricken pastures.

The new program, which goes into effect in 2006, would allow between 1,200 and 1,800 steers--mostly from out of state--to fatten up on the preserve's grasslands.

Several board members agonized over the decision, but they said the program has its advantages.

Supporters said it will bring in more revenue and provide scientists an opportunity to collect data on how cattle affect the pastures.

"We haven't tested steers yet," said board member Raymond Loretto. "We don't know what that story's going to tell us. We need to give steers a chance at least for a year."

The decision drew criticism from local ranchers and environmentalists who had hoped the existing program would be extended. Larry Armijo, president of the Jemez Pueblo Livestock Association, said the trust is taking away "alternative grazing opportunities when we need it the most."

Last year, local ranchers and the association participated in the interim program. The program cost more than $100,000 and brought in about $40,000, according to preserve figures.

Land managers have been trying to determine grazing impacts before implementing permanent grazing programs. So far, the preserve's interim programs have lost money.

Board members also raised the possibility of a future conservation program.

The board estimated that a conservation program would lose more than $83,000, while a steer-only program would lose far less--no more than $36,000.

Foregoing any grazing program for the year would be a $21,000 loss, the board estimated.

"You have to look at what you're wrestling with and put yourself in our position," board Chairwoman Tracy Hephner said. "Because part of what we have to do is figure out how to become financially self-sustaining."

Congress had mandated that the preserve, purchased by the federal government in 2000, become financially self-sustaining by 2015.