02 April 2009

Survey Underway to Determine Bird Values of Playa Wetlands

Surveys of playa wetlands in central Nebraska are underway to determine the importance of these habitats for different species of birds.

Aerial view of playa wetlands west of Broken Bow, Custer County. Image courtesy of Ben Wheeler.

"We are conducting aerial surveys for waterfowl and whooping cranes and ground surveys for shorebirds," said Ben Wheeler, wildlife biologist with the Nebraska Natural Legacy Project. "We are very excited to see what these survey efforts uncover. The Central Table Playa wetland system is a very unique ecosystem and we have very little information about the animals that use this area. This will be the most comprehensive attempt to inventory the water-related birds of the area to date."

These surveys are a part of the Nebraska Natural Legacy Project (NNLP), Nebraska's state wildlife action plan, Wheeler said. "The NNLP seeks to conserve at-risk species and their habitats in several specifically identified landscapes throughout the state. Although many of the NNLP efforts are focused on habitat projects, monitoring species and population trends is also necessary to direct the location and extent of these implementation efforts."

The Central Table Playa wetland system occurs throughout many central Nebraska counties, with higher densities of wetland complexes occurring in Custer, Lincoln and Logan Counties.

The series of flights started in early March and are expected to continue through the beginning of May, Wheeler said. "The weekly aerial survey follows a particular route based upon the location of dense wetland clusters and historic whooping crane observations. Wetlands along the route that have waterfowl or whooping cranes are mapped on a computer to be analyzed with wetland characteristics at a future date. Although the flights are not at an altitude where we can differentiate waterfowl species, the data on use by overall waterfowl is still valuable.

"Waterfowl use of these wetlands has been great. In these shallow wetlands, we see a lot of dabbling ducks (mallards, northern pintails, gadwall, northern shovelers, and teal), with a few diving ducks (ring-necked ducks, redheads, lesser scaup) in the larger and deeper wetlands."

A ground survey for shorebirds will be conducted in early May. "We are fortunate to have information about shorebird migration through efforts in other wetland systems, like the Rainwater Basin. With such information, we can intersect our survey efforts with the migration timing of many shorebirds."

Whooping cranes may be detected later in the season during their period of migration, with numerous confirmed sightings within the county in previous years.

Although there is only a small amount of information known on the birds of these playa wetlands, a breeding bird survey along a 25-mile route through the area, does convey typical species during June. A survey done in 2005 – with a "full" level of water - by T.J. Walker, an employee of the Nebraska Game and Parks Commission, noted at least these 33, representative species:

Baltimore Oriole
Bell's Vireo
Black-billed Magpie
Blue Grosbeak
Brown-headed Cowbird
Burrowing Owl
Chipping Sparrow
Common Grackle
Cooper's Hawk
Eastern Kingbird
Eastern Phoebe
Field Sparrow
Grasshopper Sparrow
Greater Prairie-Chicken
Indigo Bunting
Lark Sparrow
Loggerhead Shrike
Northern Bobwhite
Northern Mockingbird
Northern Pintail
Orchard Oriole
Pied-billed Grebe
Red-headed Woodpecker
Red-tailed Hawk
Red-winged Blackbird
Ring-necked Pheasant
Say's Phoebe
Spotted Towhee
Upland Sandpiper
Western Meadowlark
Yellow-billed Cuckoo
Yellow-breasted Chat

"The Central Table Playas are generally smaller than other popular wetland complexes, such as the Rainwater Basin in south-central Nebraska," Wheeler said. "However, the smaller size is made up for in the frequency of occurrence. For instance, in some areas of high density, we can find as many as 15 to 20 playas with a mile or two."

Many of these wetlands have been drained and farmed, according to state officials.

Aerial Photograph of playa wetlands in Township T17N R22W. Image courtesy of the National Map.

The remaining playas are classified as isolated wetlands, and are not covered under Section 404 which regulates the placement of fill into a wetland, according to John Moeschen, of the Army Corp of Engineers which is the federal regulatory agency.

"We are making some headway to conserve wetlands with programs such as the Wetlands Reserve Program, the Continuous Conservation Reserve Program and the Nebraska Natural Legacy Project," Wheeler said. "Most landowners who get involved in these programs are very pleased with the results. Often these programs offer financial incentives for ground that is only marginally productive.

"Information gained from these survey efforts will be used to modify existing wetland conservation programs or develop new programs specifically designed for the Central Table Playas. Details such as wetland size and degree of alteration are sometimes used to prioritize program implementation. Consequently, these features are also important to the critters that use the area. We need to make sure that our well-intended programs reflect the biological need and make changes if necessary.

"The success of this project will be merely based upon it's completion," Wheeler said. "No matter what we find it will be more information than we have at this point. Ultimately, we will need to begin thinking about how we can extend this project into future years. Once we have several years of information, we will be able to track changes in bird use of the area and evaluate whether our habitat projects are working or not."

This effort is a partnership which includes the Nebraska Game and Parks Commission, Rainwater Basin Joint Venture, and the U.S. Fish and Wildlife Service. Major funding has been provided through the Nebraska Partnership for All-Bird Conservation, the Nebraska Environmental Trust Fund, and the U.S. Fish and Wildlife Service.

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