DURANGO, Colo. (AP) - The U.S. Forest Service has delayed its expected announcement on whether to continue allowing domestic sheep grazing in Colorado's largest wilderness area.

In February 2016, the Forest Service released a proposed decision that determined domestic sheep grazing would continue in the Weminuche Wilderness in southwest Colorado, despite environmental concerns.

Forest Service officials previously said a final decision would be announced this winter.

However, Forest Service spokeswoman Ann Bond tells The Durango Herald that the Forest Service is still responding to public comments, and the final decision remains under internal review.

Those challenging the grazing allotments contend that domestic sheep can transmit deadly diseases to native, wild bighorns. They say the Forest Service's environmental study downplays such impacts.

Meantime, studies are being done to better understand the reclusive bighorn sheep.