Research - Ecosystems & Habitats:

Pine Ridge and Wildcat Hills Inventory

Western Nebraska’s unique landscape has everything from agricultural to river valleys to short-grass prairies to pine forest. Much of the pine forest consists of Ponderosa pine trees and resembles the Black Hills in southwest South Dakota, which has a large number of bird species including many that may be isolated groups not found in other areas in the high plains. It is feasible that some of these almost endemic species of the Black Hills would occur in Nebraska’s Pine Ridge just south of the Black Hills and potentially the Wildcat Hills region. The Pine Ridge and the Wildcat Hills regions are the focus of these studies and are deemed Biologically Unique Landscapes (BUL) by The Nebraska Natural Legacy Project. These landscapes were selected based on known occurrences of ecological communities and at-risk species (Schneider et al. 2005), and could possibly contain Tier I and Tier II bird species.

Nebraska Prairie Partners (NPP), a cooperative between Rocky Mountain Bird Observatory (RMBO) and the Nebraska Game and Parks Commission (NGPC), wanted to know what bird species occur in Nebraska’s pine forest, to better understand what birds are breeding there, what Tier I and II species are breeding there, and what type of specific habitats these birds are using. We joined the Breeding Bird Atlas Project, run by Wayne Mullhoff, to determine what birds are breeding in these forests and did distance sampling transects to get data on detection in these areas for possible future research studies.

Breeding Bird Atlas

The Breeding Bird Atlas surveys went from mid-June to early August. The surveys are set up in 3 x 3-mile square blocks and cover a span of five years. Most were done on public lands, such as State Parks and the Wildlife Management Areas (WMAs), but a few were done on private lands using county roads. Detection of the birds was by either sight or sound; we attempted to back up sound detections by confirmed sightings, but that was not always achieved. The birds were recorded by either: observed possible breeding if bird is present in suitable habitat or male is singing in suitable habitat; probable breeding determined by courtship, a pair, territorial, visiting or building probable nest to name a few; and confirmed breeding determined by carrying food or nesting material, to distraction displays, to actual nests with eggs or young, or several other actions. Confirmed breeding of all species observed would have been the ideal goal for each area, but would require considerable time to achieve.

Eighteen wooded areas were surveyed in Sioux, Dawes, Sheridan, Scottsbluff and Banner counties. Eleven sites were surveyed in the Pine Ridge, while seven sites were surveyed in the Wildcat Hills. Of the areas surveyed, 10 of the 18 were surveyed more than once due to the distance sampling transects. A total of 78 species were observed in the surveys in all habitats, with about 75 percent of those occurring in upland coniferous habitats. Only one Tier I species was observed, while 18 Tier II species were observed throughout all the surveyed sites. The Tier I species was a Long-billed Curlew and was observed in grassland in the Sowbelly Canyon survey site. Sixteen of the 18 Tier II were observed in upland or mixed, coniferous habitats. The 16 Tier II species observed in the wooded habitats were: Pygmy Nuthatch, Mountain Bluebird, Yellow-breasted Chat, Western Tanager, Blue-gray Gnatcatcher, Dark-eyed Junco, Pine Siskin, Plumbeous Vireo, Ovenbird, Cassin’s Kingbird, Black & White Warbler, Brown Creeper, Common Poorwill, Cooper’s Hawk, Golden Eagle and a Prairie Falcon. The other two Tier II species were a Brewer’s Blackbird recorded in grassland habitat in the Sowbelly site and a Swainson’s Hawk seen in grassland/shelterbelt habitat in the Bighorn WMA site. Only four of the observed species were found in all 18 surveyed sites: Mourning Dove, Chipping Sparrow, Lark Sparrow and American Goldfinch.

Distance Sampling Transects

The Breeding Bird Atlas surveys were followed up, mostly in the same areas, with transects using distant sampling to give us some idea of detection within the forested habitats of the Pine Ridge and Wildcat Hills. The assumption for the transects was that species were harder to detect the farther away they were. The transects were done throughout July, with 10 points per transect and each point about 200 meters away from the previous point. Each point was five minutes long and birds were recorded in 360 degrees by visual, singing, calling or drumming. Birds were not included if they were flying through the survey area unless they were seen before flying.

In total 12 transects were done in the Wildlife Management Areas (WMAs) and the State Parks. Two of the transects were only partially done due to equipment problems and time of day. A total of 34 species were recorded, with zero Tier I and eight Tier II species, which were: Pygmy Nuthatch, Yellow-breasted Chat, Western Tanager, Mountain Bluebird, Golden Eagle, Ovenbird, Cooper’s Hawk and Blue-gray Gnatcatcher. The transects tell us that only a handful of species seem unconcerned about humans or pay no attention to humans. Some species are more secretive around humans, but still sing or call, while others like House Wrens make it known that they are not happy with a human being so close to their area. Only three species were seen in all 12 transects: Spotted Towhee, Mourning Dove and Chipping Sparrows. House Wrens and Pygmy Nuthatches were seen in 11 of the 12 transects. Black-capped Chickadee and Western Wood-Pewee were recorded in 10 of the 12 transects. The most observed species throughout the transects were: Western Wood-Pewee, Spotted Towhee, Black-capped Chickadee, House Wren and Mourning Doves. These top five were frequently seen as they were recorded in 10 of the 12 transects or more. The next most observed species on the list was Pygmy Nuthatch, which is a Tier II species.

Reptile Study

An attempt was made to also look at what reptile species occurred in the Pine Ridge and Wildcat Hills. Four-foot by two-and-three/fourths-foot pieces of plywood were placed out in the WMAs and State Parks to see what reptiles would use them to stay warm. At least two boards were placed in each area – one on the edge of the tree line and the second well into the forest to see what species were in each area. After the boards were in place and UTM coordinates taken, they were left for at least two weeks until they were checked.

The boards were placed in: Gilbert-Baker WMA, Fort Robinson, Ponderosa WMA, Bighorn WMA, Chadron State Park, Chadron Creek Ranch WMA, Bordeaux WMA, Metcalf WMA, Cedar Canyon WMA, Wildcat Hills SRA, and Buffalo Creek WMA. Gilbert-Baker WMA and Wildcat Hills SRA each had three boards, with one on the edge of tree line and two in different forest locations to increase our sample size. The boards were checked in the morning or at dusk. We were disappointed to find no reptiles at all and assume that it was too late in the season and too hot for reptiles to use the boards.

Literature Cited

Schneider, R., M. Humpert, K. Stoner, G. Steinauer. 2005. The Nebraska Natural Legacy Project: A comprehensive wildlife conservation strategy. Nebraska Game and Parks Commission, Lincoln, NE.