Sandhills Grassland Bird Study

In May of 2002, Matt Proett (graduate research assistant, UNL), and his assistants Jace Millikin (AR) and Shona Lawson (B.C., Canada) initiated field work on a study of the effects of various grazing systems on grassland birds in the Nebraska Sandhills. This project was initiated by a grant from the Sandhills Task Force and is being conducted under the direction of Dr. Larkin Powell (professor of wildlife ecology, UNL). Additional support for the study came from Nebraska Game and Parks Commission, Sampson Range and Pasture Management Endowment, the University of Nebraska, and the USDA's Sustainable Agriculture Research and Education Fund.

Prior to the field season, several Sandhills ranchers were contacted by Jim Van Winkle (STF, Projects Coordinator) about participation in the study. Twelve of these ranchers gave permission for surveys to be conducted on their land. Pastures from 8 of these ranches were selected for the study based on geographic location, landscape characteristics, and grazing systems in use. The geographic area encompassed by the study area included the eastern third of Cherry County, NE and northern Thomas County.

From these 8 ranches, 9 upland study sites were selected for use in the 2002 field season. Three sites from each of the following broadly defined grazing systems were selected: continuous grazing, medium-duration (e.g., 4-pasture systems) grazing, and short-duration (e.g., management intensive) grazing. Temporary line transects were established on the sites (3000 meters of transect per site, approximately 1.8 miles) and bird surveys were conducted along these transects. Additionally, vegetation structural characteristics were sampled along these transects and nests located in the vicinity of the transects were monitored to determine nest success.

Between June 4 and July 22, all study sites were surveyed 9 times. Surveys were conducted between approximately 5:30 am and 9:00 am. Using a technique known as distance sampling, observers recorded distances and bearings to all birds detected along the transect lines. This data will be used to calculate actual bird densities and to determine if differences exist among sites. Thirty species of birds were recorded on the sites in the 2002 field season (see complete species list). Several of these species such as Grasshopper Sparrow, Western Meadowlark, and Upland Sandpiper have experienced significant populations declines in various parts of the country, although little is known about their population status in the Sandhills.

Additional information regarding population trends may be gleaned from nest studies. Nests were located as observers walked along transect lines and were actively searched for in late mornings and early afternoons with the aid of a 100 ft. weighted rope dragged between 2 observers. Crew members returned to nests every two to four days to determine nest fate. Fifty-eight nests were located and monitored during the field season. Species whose nests were found in highest numbers were Grasshopper Sparrow (11 ), Western Meadowlark (10), and Lark Sparrow (9) (see complete nest list). Of the 39 passerine nests monitored, 11 (28%) fledged at least one host young, 26 (67%) failed or fledged only parasite young, and 2 were not successfully relocated. Only 2 (5%) nests showed visual evidence of damage resulting from cattle. Nest numbers were lower than expected as many double- and triple-brooded species presumably did not attempt multiple clutches due to extreme drought conditions.

Due to variations in stock densities and duration, historic use of pastures, and landscape characteristics, grazing system alone may not account for potential variations in bird density, diversity, and nest success among sites. Knowing this, vegetation structure was sampled on all study sites to quantify potential variation among sites. This data will be especially valuable to take into account the effects of the drought during summer 2002.

We want to especially thank all the ranchers participating in the study. They took the time to describe their grazing systems to us and show us around their ranches. All ranchers gave us unlimited access to their pastures for the summer. We enjoyed the opportunity to work with them, and we look forward to the project's next field season in 2003.

Western meadowlark

Grasshopper sparrow

Lark sparrow

Lark bunting

Upland sandpiper

Long-billed curlew

Greater Prairie chicken

Sharp-tailed grouse

Mourning dove

Common nighthawk

American crow

Field sparrow

Mallard

Brown-headed

Cowbird

Red-winged blackbird

Northern harrier

Orchard oriole

Indigo bunting

American goldfinch

Blue-winged teal

Eastern kingbird

Western kingbird

Dickcissel

Brown thrasher

Eastern towhee

Bell's vireo

Horned lark

Killdeer

Ring-necked pheasant

Common grackle

Grasshopper sparrow (11 )

Western meadowlark (10)

Lark sparrow (9)

Mourning dove (9)

Lark bunting (8)

Common nighthawk (5)

Upland sandpiper (2)

Mallard (2)

Sharp-tailed grouse (1 )

Field sparrow (1 )

Below is a fact sheet that answers the more common questions, people may have about allowing someone to survey their property.

LANDOWNER FACT SHEET

Q:  Who is responsible for this project?

A: This project is a collaboration between the Sandhills Task Force, University of Nebraska, and Nebraska Game and Parks.  Most of the field research will be done by graduate students from the University of Nebraska.

Q: How often will you need to be on my land?

A: We plan to visit each pasture during three periods of the birds’ breeding season.  Each visit will consist of three surveys, resulting in 9 total surveys during the summer.  We will do the surveys from late May until early July.

Q: Why are you doing the research?

A: The actual research will be conducted by the University of Nebraska - Lincoln.  The Sandhills Task Force is sponsoring the research.  The Sandhills Task Force is an organization consisting of ranchers and conservation agencies whose goal is to support private ranching and wildlife.  Although we know different grazing systems benefit different types of wildlife, research information will help the Task Force and ranchers to better develop grazing programs that work the best for ranching and wildlife.

Q: What happens if you find an endangered bird species on my land?

A:   It is the University’s policy that information specific to your property is confidential and will not be shared with the public, organizations, or government agencies without your permission.

Q: What will you do on my land?

A: Our researchers will conduct surveys early in the morning, from 6-9 a.m.  They may also search for nests, collect insects, and measure vegetation during other parts of the day.  The surveys will consist of walking the edges of a rectangle, approximately ½ mile by 1/4 mile.  Surveyors will be using Global Positioning Units to guide them, but they may need to use small amounts of biodegradable flagging or spray paint at certain intervals to mark the survey route.      

Q: How will you travel across my land?

A: The actual surveys will be done on foot.  Researchers will obtain your permission for where they can drive and/or walk on you property.  Researchers will be chosen on their ability to work closely with landowners, and will be instructed of the critical importance of closing gates, respecting your land, and working around your livestock. 

Q: How can I contact you if there is a problem?

A: Once you have agreed to participate in this project, we want to be sure that you continue to feel comfortable.  Please contact us if you have any questions.  A contact for the Sandhills Task Force is Gene Mack, (308) 236‑5015  ext. 27.  A contact with the University of Nebraska is Larkin Powell (402) 472-6825.  We will also supply you with a list of the researchers who will be on your land this summer.