If left unchecked, growing numbers of elk and wild cattle could leave New Mexico's Bandelier National Monument eroded and overgrazed, park officials say. Nearly 30 cows and over 2,000 elk now trample the park's fragile hillsides and brittle archaeological ruins and, according to an environmental assessment released Jan. 13, the cattle herd could double in three years. The report recommends that managers shoot the feral cattle by March and leave the carcasses for local scavengers. However, during the two-week public comment period, more than 30 people volunteered to round up and keep the cows, says manager Charisse Sydoriak. She worries a roundup would damage park resources and fail to catch all the cows. She says the park may combine a restricted roundup with some shooting. The agency's plans for dealing with elk are less definite. Since a massive fire in 1977 created new meadows, elk numbers in Bandelier have grown exponentially, concludes another report. But before they can limit Bandelier's elk, park managers need a detailed study of their impact, a project Sydoriak says could take over three years. For more information, contact Bandelier National Monument, Los Alamos, NM 87544 (505/672-3861).