One national forest near the New Mexico-Arizona border has had a problem with feral cattle for years.
Federal wildlife agents plan to put more of a dent in the population next week by gunning down the animals via helicopter.
But the New Mexico Cattle Growers' Association is concerned about the agents' ability to delineate branded from unbranded livestock.
There also are concerns that leaving cow carcasses on the landscape will only help attract wolves and put livestock at greater risk of predation.
Federal officials didn't immediately say how many cattle will be targeting during the operation on the Gila National Forest.