Birds & Science >
Colorado IBAs
Pawnee National Grassland
Weld County
Size: 193,060 acres
Elevation: 4500 - 5500 feet
Habitats:
Primary – grassland
Secondary – open water, rocky arroyos, bluffs, woodland
Ownership:
Federal (U.S. Forest Service)
Land Use:
Nature and wildlife conservation, hunting/fishing, recreation/tourism, utility/right-of-way, research
IBA Criteria: 1, 2, 3, 4 (waterfowl, shorebirds, raptors, landbirds), 5
ABC Status:
Globally significant
Site description
Location:
Pawnee National Grassland is located in northeastern Colorado, near the town of Briggsdale.
Vegetative/natural features:
This shortgrass prairie ecosystem is bordered on the north by the High Plains (500 feet higher) with a transition zone between known as the Chalk Bluffs. Within the shortgrass prairie are the Pawnee Buttes, two 500-foot remnants of the High Plains. The Colorado Native Plant Society has identified several plant communities at the site worthy of special study.
Historic features:
The federal government created the Pawnee Grassland during the 1930s Dust Bowl to reclaim land that had been inappropriately farmed. There are numerous pre-historical and historical sites in the area, on both public and private land.
Ornithological Importance
This is one of the main breeding grounds in the world for Mountain Plovers. The Chalk Bluffs area is habitat for many raptor species.
Breeding species:
|
Average #
|
Maximum #
|
Burrowing Owl
|
50
|
|
Mountain Plover
|
~1500
~1500
|
|
Ferruginous Hawk
|
|
6-50
|
American White Pelican
|
100
|
|
Brewer’s Sparrow
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|
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Baird’s Sparrow
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|
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Swainson’s Hawk
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~60+
|
|
American Avocet
|
|
|
Northern Harrier
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~100
|
|
Prairie Falcon
|
|
|
McCown’s Longspur
|
>3000
|
|
Cassin’s Sparrow
|
|
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Lark Bunting
|
>5000
|
|
|
|
|
|
Migrant species:
|
Average #
|
Maximum #
|
Sandhill Crane
|
1000 (spring)
|
|
Long-billed Curlew
|
~20 (spring)
|
|
Swainson’s Hawk
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>400 (fall)
|
|
raptors
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>1000 (fall)
|
|
shorebirds
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>750 (spring)
|
|
waterfowl
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>2000 (fall)
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|
|
|
|
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Wintering species:
|
Average #
|
Maximum #
|
Ferruginous Hawk
|
|
2-10
|
|
|
|
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Research and educational activities:
The University of Northern Colorado, Colorado State University, U.S. Fish and Wildlife Service, and U.S. Forest Service have conducted research at the site for many years.
Conservation/Management Issues
Serious threats:
- predators (swift fox on Mountain Plover);
- disturbance to birds (the causes of decline of Mountain Plover and other grassland species is unknown).
Minor threats:
- development;
- impact from increasing recreation.
Management details:
The ownership pattern in the Pawnee Grassland is checkered – private and public. The public land is managed under the U.S. Forest Service’s "multiple-use" concept, while surrounding private land is grazed and farmed for wheat, corn, alfalfa, beans, and sunflowers. There are two Colorado Watchable Wildlife sites within the Grassland.
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