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Alamosa and Rio Grande Counties
Size: 11,169 acres (Alamosa NWR), 15,831 acres (Monte Vista NWR)
Elevation: 7500 feet

Habitats:
Primary – wetlands, semidesert shrubland
Secondary – rural/agricultural, open water, high elevation riparian

Ownership:
Federal (U.S. Fish & Wildlife Service)

Land Use:
Primary – nature and wildlife conservation, agriculture/livestock, hunting
Secondary – recreation/tourism, research

IBA Criteria: 1, 4 (waterfowl, heronries, shorebirds, gulls/terns, raptors, landbirds), 5

Site description

Location:
Located in the San Luis Valley in south-central Colorado, Alamosa National Wildlife Refuge is east of the town of Alamosa in Alamosa County, while Monte Vista National Wildlife Refuge is west of the town of Alamosa in Rio Grande County.

Vegetative/natural features:
Alamosa NWR consists of wet meadows, river oxbows, and riparian corridors within the floodplain of the Rio Grande River, and dry uplands containing greasewood and saltbrush. The site also contains a cottonwood riparian area, willows, and cattail and bullrush wetlands.

Wetland habitats in Monte Vista NWR include shallow wet meadows, open water, bullrush and cattail meadows. The site also contains isolated patches of cottonwoods, high desert shrubland (greasewood and rabbitbrush communities), and farmland that produces grain for cranes and other wildlife.

Ornithological Importance

Concentrations of waterfowl at the refuge complex exceed 20,000 annually. The complex provides important habitat for migrating and breeding waterfowl and shorebirds, and serves as an important migration corridor along the Rio Grande for migrating passerines. Species that use the refuges include Black-necked Stilt, Sora and Virginia Rail, American Bittern, Peregrine Falcon, American White Pelican, American Avocet, and Wilson’s Phalarope.

Alamosa NWR may host Southwestern Willow Flycatchers. The Migratory Bird Conservation Commission established the Monte Vista National Wildlife Refuge in 1953 to provide habitat for wildlife, particularly waterfowl, in the San Luis Valley. The site is a major stopover for migrating Greater Sandhill Cranes moving between their wintering area around Bosque del Apache National Wildlife Refuge in New Mexico and breeding grounds in the northern U.S. and southern Canada. Two remaining Whooping Cranes, from a failed attempt to establish a wild migratory population, migrate with the sandhills. The site contains a number of heronries (exceeding 200 pairs) that produce White-faced Ibis, Snowy and Cattle Egrets, and Black-crowned Night Heron.

Research and educational activities:
Researchers have surveyed 171 miles of waterfowl nesting transects at the refuge complex two to three times a year since 1965. Monitors conduct waterfowl pair counts and brood counts every summer during the breeding season. Annual population estimates are made for nesting colonies of ibis, egrets, and night herons. San Luis Valley and refuge-wide crane counts are conducted each spring and fall at peak migration.

Conservation/Management Issues

Serious threats:

• invasive/non-native plants;
• introduced animals.

Potential threats:

• disturbance to birds and habitat.

Efforts to address threats:
The Alamosa and Monte Vista National Wildlife Refuge Complex is currently being researched for the effects of livestock grazing on weed species and nesting waterfowl.

Management details:
Alamosa is less intensively managed than Monte Vista. Land managers manipulate water at the site to some extent, however, and also utilize burning and grazing. Water from the Rio Grande River is supplemented by artesian wells and pumped water from the Closed Basin Project.

Water is intensively managed at Monte Vista to create wetland habitats ranging from shallow wet meadows to open water. Land managers utilize mowing, grazing, prescribed burning, and farming to manage habitat.

The headquarters and visitor center for both Alamosa and Monte Vista National Wildlife Refuges are located at Alamosa NWR. Alamosa and Monte Vista National Wildlife Refuges are Colorado Watchable Wildlife sites.