The mule deer herd that winters on the mesa east of Pinedale has suffered a 46 percent population decline since 2002, despite a Bureau of Land Management policy that banned most natural gas drilling in the area in wintertime. Now, the BLM wants to allow several more companies to drill throughout the winter — and some conservationists think the change might actually result in better wildlife protection.

Starting in 2000, the BLM prohibited drilling on the mesa between Nov. 15 and April 30. But in 2003, the agency gave Questar permission to drill year-round; this September, it gave the same permission to Anschutz, Shell and Ultra. In return, the companies have agreed to bus their workers out to well sites and to use directional drilling. That will mean less traffic, less surface disturbance and less habitat fragmentation, says Shell spokeswoman Deena McMullen.

Biologist Hall Sawyer of Western EcoSystems Technology Inc., whose Questar-funded study revealed the deer’s decline, says the winter ban did not sufficiently protect wildlife, partly because it allowed truck traffic to service existing wells. He thinks wildlife survival may depend on measures similar to those proposed by the companies. Vern Stelter, habitat protection program supervisor with the Wyoming Department of Game and Fish, says that his agency supports lifting the winter ban for the companies because their mitigation plans offer enough other benefits for big game.

Though environmentalists are willing to see whether the one-year trial will stem the loss of deer, they aren’t ready to accept an industry proposal to eliminate the ban permanently. "Seasonal stipulations are not a magic wand to protect wildlife," says Peter Aengst of The Wilderness Society. But, he says, the winter ban can serve as a "trading chip," encouraging companies to offer additional environmental protections.