Surveying a playa in native prairie, Colorado
Playas, a numerous but elusive wetland type in our region, fill only periodically
from heavy rainfall. These shallow, round temporary lagoons support great biodiversity
as an essential component of the Shortgrass Prairie ecosystem. The wet-dry cycles
of playas produce high abundances of insects and annual plants that provide nutritious
seeds, especially important to migrating waterfowl and shorebirds in our region
that stop over on playas to rest and refuel during their long journeys between wintering
and breeding grounds. These shallow, seasonal wetlands also provide other important
societal wetland functions, including capture of surface runoff, flood attenuation,
and aquifer recharge. Threats to playas include pressure from growing urban development
and agricultural uses that lead to increased sedimentation rates, pit excavation,
road construction, feedlot runoff, overgrazing, and deliberate filling.
We have been studying playa wetlands in eastern Colorado since 2004, to improve
understanding of the locations and conditions of these important wetlands. Our overall
goal is to enhance the conservation of playa habitat on the Shortgrass prairie for
the future. Our research provides vital information for designing strategic conservation
efforts at the landscape scale as well as for informing the specific prescriptions
of future habitat enhancement projects. Our research approach combines field data
for bird use and playa condition with digital maps of playa locations in a Geographic
Information System (GIS).
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Playa in Shortgrass Prairie, Colorado
We have created and verified a GIS map indicating the locations of approximately
7800 playas in eastern Colorado. Through our study, we have compiled information
on the plant life, bird use, and general ecological characteristics of over 1100
playas, creating the only dataset of its kind (see report). We found playas are
not randomly distributed in eastern Colorado and playas are larger and more numerous
in certain counties. We are creating maps to summarize what we have learned about
the conditions of playas in Colorado – where they average to be larger sizes, occur
in higher densities on the landscape, are primarily located in farmland or prairie,
etc. In addition, we are relating bird use to the characteristics of playas, to
learn what features are most important in comprising high-quality migratory bird
habitat. These analyses will be completed and posted online by the end of 2008.
In addition to this research, Rocky Mountain Bird Observatory also directly conserves
playa habitats through on-the-ground habitat improvements. We work with private
landowners (more than 80% of eastern Colorado is in private ownership) through Prairie
Partners, which offers voluntary, incentive-based
Playa in farmland in Phillips County, CO
programs to enhance and restore playas for future generations. These are win-win
situations for wildlife as well as agricultural producers. Private landowners are
interested in conservation programs for playas for a variety of reasons, including
the recreational opportunities (hunting and wildlife viewing), aquifer recharge
benefits, and because playas can be problematic for farming and ranching. Conservation
programs may entail grazing management and alternate water development or retirement
and buffering the playa from farming and usually entail cost-share agreements and/or
rental payments.
Related Projects
In a related project, Floristic Quality and Wildlife Habitat Assessment, we investigate
how bird use, plant composition, and human disturbance relate within playa wetlands
of eastern Colorado (cick
here for the report). We are also conducting a Biological
Inventory and Buffer Evaluation of Nebraska’s Southwest Playas.
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Playa bisected by the road, Colorado
More about Playas
Playas are shallow, depressional wetlands of the Great Plains that fill periodically
from heavy rainfall and associated runoff (Smith 2003). Over 60,000 occur throughout
northern Texas, western Oklahoma, Kansas, Nebraska, and eastern New Mexico and Colorado
(Playa Lakes Joint Venture 2008). Playa wetlands provide important ecological and
societal functions (Haukos and Smith 1994), including flood abatement, recharge
to the Ogallala aquifer (Zartman 1994, Wood 2000), water for livestock (Ostercamp
and Wood 1987), support for biodiversity (Bolen et al. 1989), critical shorebird
migration stopover habitat (Skagen and Knopf 1993; Davis and Smith 1998), and winter
and migration habitat for waterfowl (Nelson et al. 1983). Playas are threatened
by development pressures and agricultural uses that have led to increased sedimentation
rates, pit excavation, road construction, feedlot runoff, urban development, overgrazing,
and deliberate filling (Haukos and Smith 2003). Finally, because these clay-lined
wetlands occur in closed watersheds, they are considered geographically isolated
and not currently protected under the Clean Water Act (Haukos and Smith 2003).
To learn more about playas go to www.pljv.org.
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Literature Cited
Bolen, E.G., L.M. Smith, and H. L. Schramm Jr. 1989. Playa lakes: prairie wetlands
of the Southern High Plains. Bioscience 39:615–623.
Davis, C.A., and L.M. Smith. 1998. Behavior of migrant shorebirds in playas of the
southern high plains, Texas. The Condor 100:266-276.
Smith, L.M. 2003. Playas of the Great Plains. University of Texas, Austin, TX.
Haukos, D.A., and L.M. Smith. 1994. The importance of playa wetlands to biodiversity
of the Southern High Plains. Landscape and Urban Planning 28:83–98.
Haukos, D.A., and L.M. Smith. 2003. Past and future impacts of wetland regulations
on playa ecology in the southern Great Plains. Wetlands 23:577-589.
Nelson, R.W., W.J. Logan, and E.C. Weller. 1983. Playa wetlands and wildlife on
the Southern Great Plains: a characterization of habitat. US Fish and Wildlife Service,
Albuquerque, NM.
Ostercamp, W.R. and W.W. Wood. 1987. Playa-lake basins on the Southern High Plains
of Texas and New Mexico, Part I. Hydrologic, geomorphic, and geologic evidence of
their development. Geological Society of America Bulletin 99:215-223.
Skagen, S.K., and F.L. Knopf. 1993. Toward conservation of midcontinental shorebird
migration. Conservation Biology 7:533-541.
Wood, W.W. 2000. Ground-water recharge in the Southern High Plains of Texas and
New Mexico. U.S. Geological Survey. FS-127-99.
Zartman, R.E. 1994. Playa lakes on the Southern High Plains: reevaluating infiltration.
Journal of Soil and Water Conservation 49:299–301.
Programs
We are joined many others in the conservation community that also offer playa conservation
programs, including the Colorado Division of Wildlife (CDOW), Nebraska Game and
Parks Commission, (NGPC), U.S. Fish and Wildlife Service (USFWS) Partners for Fish
and Wildlife Program, Playa Lakes Joint Venture (PLJV), and the Natural Resources
Conservation Service (NRCS).
Photos
American Avocet, a common migrant on Colorado playas, courtesy of Tony Leukering
Long-billed Curlew, a species of conservation concern that uses playas, photo courtesy
of Tony Leukering
The rich seed source provided by playa wetlands
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Contact:
Alison Cariveau
Alison.Cariveau@rmbo.org
State: Colorado
Funders:
- Colorado Division of Wildlife
- US Environmental Protection Agency
- Playa Lakes Joint Venture
- U.S. Fish and Wildlife Service
Cooperators:
- Colorado Natural Heritage Program
- Ducks Unlimited, Inc.
- The Nature Conservancy
Materials:
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