Baca National Wildlife Refuge, National Wildlife Refuge in San Luis Valley, Colorado.

Baca National Wildlife Refuge is a federally protected area in Colorado's San Luis Valley, covering wetlands, grasslands, and shrublands at the foot of the Sangre de Cristo Mountains. The land is managed to support native wildlife, including birds, fish, and large mammals that move through the valley.

Congress authorized the refuge in 2000 in the same legislation that created Great Sand Dunes National Park. It was formally established in 2003 under the U.S. Fish and Wildlife Service. The land came largely from the historic Baca Ranch: about 97,036 acres were bought by the Nature Conservancy before transfer to the federal government, and some 3,300 acres previously managed by the Bureau of Reclamation were reassigned to the refuge.

The refuge occupies part of the Luis Maria Baca Grant No. 4, a land grant tied to the Baca family. The historic Baca Ranch headquarters and other ranch buildings still stand on the refuge, and grazing and hay production continue on a limited basis, including several thousand acres of irrigated hay meadows.

The refuge lies on the west side of the Sangre de Cristo Range, about 30 miles northeast of Alamosa and roughly 17 km from Crestone, at an elevation of about 2,299 metres. Grazing and hay production continue on a limited basis, and the original ranch headquarters buildings stand on the refuge. Mineral rights belong to a third party, Lexam Explorations, so access for gas exploration is governed by federal agreements.

Crestone Creek, which runs through the refuge, shelters four native fish species that are found in very few places outside this valley. Their survival depends on the specific mix of cold mountain water and the flat valley floor, which makes this creek an unusual habitat.