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Western Nebraska’s landscape is very unique considering it has everything from agricultural,
to river valleys, to short-grass prairies, to pine forest. A large portion of the
pine forest consists of Ponderosa pine trees and resembles the Black Hills in the
southwest corner of South Dakota. The Black Hills contain a large amount of bird
species with many possibly being isolated groups that are not found in other areas
in the high plains. With the Pine Ridge occurring just south of the Black Hills
it was feasible to conceive that some of these almost endemic species of the Black
Hills would occur in the Nebraska Pine Ridge and potentially the Wildcat Hills region.
The Pine Ridge and the Wildcat Hills regions were the focus of these studies and
are deemed Biologically Unique Landscapes (BUL) (Schneider et al. 2005), 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), which 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 do occur in Nebraska’s pine forest for a better understanding of what birds
are breeding there, what Tier I and II species are breeding there, and what type
of specific habitats these birds are using. To achieve this I was put on the Breeding
Bird Atlas Project, run by Wayne Mullhoff, to determine what birds are breeding
in these forest, and I did distance sampling transects to get primarily data on
detection in these areas for possible future research studies. To further our knowledge
of these areas, we also did some reptile studies using sheets of plywood to see
what reptiles might be using the boards to stay warm.
Breeding Bird Atlas
The Breeding Bird Atlas surveys went from mid-June to the first week or so of August.
The Breeding Bird Atlas surveys are set up in 3 x 3 mile square blocks and cover
a span of five years. Most of the surveys were done on public lands, like the State
Parks and the Wildlife Management Areas (WMAs), but a few were also done on private
lands using County roads. Detection of the birds was by either sight or sound, with
sound detections then attempted to be backed up by confirmed sighting, but 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 with several actions to determine this like courtship, a pair,
territorial, visiting or building probable nest to name a few; and then confirmed
breeding again with several actions to determine this from carrying food or nesting
material, to distraction displays, to actual nests with eggs or young, with several
other actions not mentioned. Confirmed breeding of all species observed would have
been the ideal goal for each area, but is very time consuming to achieve.
In total, 18 wooded areas were surveyed that occurred in Sioux, Dawes, Sheridan,
Scottsbluff, and Banner Counties with more sites occurring in the Pine Ridge. In
the Pine Ridge, 11 sites were surveyed, while 7 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
over all habitats, with around 75% of those occurring in upland coniferous habitats.
Only 1 Tier I species was observed, while 18 Tier II species were observed throughout
all the surveyed sites. The 1 Tier I species was a Long-billed Curlew and was observed
in grassland in the Sowbelly Canyon survey site, while 16 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 2 other Tier II
species were a Brewer’s Blackbird recorded in grassland habitat in the Sowbelly
site, while the other was a Swainson’s Hawk seen in grassland/shelterbelt habitat
in the Bighorn WMA site. Of all the species observed, only 4 were observed in all
18 surveyrd sites with them being: Mourning Dove, Chipping Sparrow, Lark Sparrow,
and American Goldfinch.
Distance Sampling Transects
The Breeding Bird Atlas surveys were then followed up, in most of the same areas,
with transects using distant sampling to give us some idea of detection within these
forested habitats of the Pine Ridge and Wildcat Hills. The assumption of the transects
was that species were harder to detect the further away they were. The transects
were all done throughout the month of July, with 10 points per transect, with 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 with all of them being done in the Wildlife Management
Areas (WMAs) and in the State Parks. Two of the transects were only partially done
due to equipment problem and time of day. A total of 34 species were recorded, with
0 Tier I and 8 Tier II species. The Tier II species were: Pygmy Nuthatch, Yellow-breasted
Chat, Western Tanager, Mountain Bluebird, Golden Eagle, Ovenbird, Cooper’s Hawk,
and Blue-gray Gnatcatcher. What the transects tell us is that there is only a handful
of species that seemed 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 very known that they are not happy with that human being
so close to their area. There were only 3 species seen in all 12 transects, which
were: Spotted Towhee, Mourning Dove, and Chipping Sparrows, while 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 very frequently seen
as they were also 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. The idea was to place 4 foot by 2 ¾ foot pieces of plywood out
in the WMAs and State Parks to see what reptiles were using them to stay warm. At
least 2 boards were placed in each area with one being on the edge of the tree line
and the second board being placed well into the forest. We hoped to see what species
were around tree line and what species occurred well into the forest. Once the boards
were in place and UTM coordinates were taken, they were left alone for at least
2 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 3 boards, with 1 on the edge of tree line and 2 in the forest
in different locations to increase our sample size. The boards were checked in the
morning or right at dusk. After checking all the boards, we were disappointed to
find no reptiles at all. The only assumption that we take from this was it was already
too late in the season and thus, too hot for reptiles to be using the boards.
Literature Cited
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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.
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Contact:
Bart Bly
Bart.Bly@rmbo.org
State: Nebraska
Funder:
- Nebraska Environmental Trus
- Nebraska Game and Parks Commission
- University of Nebraska - Lincoln
Cooperators:
Materials:
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