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INTRODUCTION
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Human development and changing land use patterns have altered many stream habitats in
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the U.S. and throughout the world (Bond and Lake 2003). Physical alterations to the stream
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channel cause changes in water flow (i.e. increased speed), increase the risk of erosion and
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negatively impact wildlife habitat quality both in and around the stream (Bond and Lake 2003).
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Efforts to restore human impacted creeks and reverse these effects have increased in recent years
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(Palmer et al. 1997) although success in improving habitat conditions for fish or other species are
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limited (Smokorowski et al. 1998) due in part to a lack of evaluation of restored habitats (Lake
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2001).
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Cullowhee Creek is a small stream in western North Carolina on the campus of Western
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Carolina University (WCU). Construction activity and adjacent land use had greatly altered the
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structure and flow of the portion of the creek running through campus. In 2005, efforts were
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made to restore this channel in order to improve water quality and create a stream structure more
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suitable for fish and aquatic species. Specific improvements included placing rock weirs in the
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stream channel, grading and reseeding stream banks (Allmendinger, 2005).
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The purpose of this study was to conduct a simple evaluation of major physical, land use
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and biologic attributes of Cullowhee Creek to assess conditions following restoration and to
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develop potential management steps.
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Specific objectives included:
1. Develop an evaluation to examine the physical structure, land-use and biologic
conditions at Cullowhee Creek on the campus of WCU
2. Use systematic sampling to conduct the evaluation at numerous locations along the
creek
3. Compile and analyze survey results
4. Provide specific management recommendations to either improve or maintain
conditions at Cullowhee Creek.
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STUDY AREA
Cullowhee Creek is located on the campus of WCU in the Appalachian mountains of
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western North Carolina (Figure 1). Topography ranges from nearly flat in the creek valley to
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steep and mountainous with elevation along the creek approximately 600 meters. Annual
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precipitation varies throughout the region but in the Cullowhee area is approximately 127 cm per
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year (USDA 1997). Deciduous forests dominate the landscape in the region although land use
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along the portion of the creek studied here is dominated by WCU infrastructure and recreational
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and residential facilities. Some areas adjacent to the creek are forested though limited access
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prevented extensive evaluation of these sites.
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METHODS
To evaluate Cullowhee Creek the Natural Resource Management140 (section 03) adapted
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a survey developed by Petersen (1992). Evaluation categories included land use, physical
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attributes, and biologic attributes. Specific criteria within each category were adapted to reflect
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conditions at the study area and to be easily calculated by observers. Individual criteria were
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scored on a 0-1 scale with 1 being optimal (Table 1). A complete survey is included in
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Appendix A.
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Table 1. Sample question from a survey adapted for use at Cullowhee Creek.
Land Use
Land use in riparian zone (adjacent to or w/in 10 meters of channel)
Points
_____Natural or undisturbed forest or wetland
1.0
_____Minor disturbance (walking path, road) with some natural vegetation
.75
_____Mostly grass/lawn with parking lot, road, buidlings, within ____m/ft
.50
_____No or very little vegetation, adjacent roads, lots, buildings etc.
.25
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Types of man-made structures
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We sampled systematically recording scores for each criterion at 100 ft intervals along
_____No man made structures
1.0
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the creek. Scores for all groups and locations were compiled and the entire section of creek
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sampled
here and
average with
scores
werelot,
calculated.
Management
recommendations
_____Mostly
grass/lawn
parking
road, buildings,
within ____m/ft
.50 were made
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_____No
or very
little vegetation,
lots, buildings
based
upon these
scores
and from adjacent
general roads,
observations
of theetc.
conditions at the .25
creek.
_____Minor disturbance (walking path, road) with some natural vegetation
.75
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Landuse adjacent to riparian zone (Within_____________m/ft)
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RESULTS
____Undisturbed forest, wetland or other natural habitat
OfLimited
the 3 disturbance
major categories
evaluated,
____
(park, trails
etc.)
1.0
land-use scored consistently between
.75 0.50-0.60
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____Lower
impact human
use (no
industry,
mining,
farming
etc.)
.50land use however
(Figure
3). Confidence
intervals
show
slightly
greater
variation
in the adjacent
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____ High impact human use (industry, farming, business)
.25
average
values were similar to other land use characteristics. Both physical and
biologic
Landuse adjacent to riparian zone (Within_____________m/ft)
3
____Undisturbed forest, wetland or other natural habitat
1.0
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categories had much greater variation among measured criteria with stream channel and bank
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average scores at or below 0.5 and stream bottom and surface were at or above 0.7 (Figure 3).
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Among biologic criteria, both aquatic vegetation and animal species scored approximately 0.40
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while terrestrial vegetation and wildlife were much higher with an average score of 0.60 and 0.80
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respectively. Confidence intervals around average scores were generally 0.1 or less for all values
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(Figure 3).
1.00
0.90
0.80
0.70
0.60
0.50
0.40
0.30
0.20
0.10
0.00
Riparian
Land Use
Structures
Adjacent
Land Use
Stream
Channel
Stream Bank
Stream
Bottom
Surface
Aquatic
Vegetation
Terrestrial
Vegetation
Aquaitic
species
Terrestrial
w ildlife
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Figure 3. Average scores for criteria measured within the three major categories Land Use
(Gray), Physical Attributes (Blue) and Biologic Attributes (Green).
DISCUSSION
The prevalence of human land use adjacent to the creek likely explains why land use
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scores were low and consistent across sample sites (e.g. Bond and Lake 2003). Most sites
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sampled were either directly affected by human activity or adjacent to human activity and land
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use such as residential and recreational facilities. Higher variation in the physical aspects of the
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channel indicates much less consistency in stream quality across the study area. The lower
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scores for the stream channel likely reflect the ‘channelized’ pattern. While restoration did focus
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on returning some structure into the channel (Allmendinger 2003) it is not possible to entirely
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restore a meandering pattern hence this value will likely remain low even with management.
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With the restoration occurring recently, the stream bank still showed signs of exposed soil hence
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this value remains fairly low and presumably will increase as vegetation recovers.
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The presence of pools, runs, and riffles indicate a variety of bottom structure and the
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addition of structures into the stream further enhanced this which likely accounts for the marked
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difference between stream bottom and surface measures and the channel values. The physical
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structure was not quantified thus it is difficult to evaluate the nature of the stream bottom in
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detail.
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While there was a great deal of variation within the biologic factors, the low score
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assigned aquatic vegetation may also reflect the time of year when this study was conducted.
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The absence of fish in the main channel may also reflect the time of year but may be indicative
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of remaining work needed to further enhance fish habitat. It is somewhat surprising that
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terrestrial vegetation scored high given the level of human activity. This may be due to the
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nature of the sample questions and may reflect a need to sample more quantitatively and look
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specifically for natural vegetation. A number of terrestrial wildlife species were seen but no
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effort was made to quantify the numbers or to group by species. The conspicuous nature of some
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species such as songbirds may also have helped to inflate this value. Future efforts should
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examine actual habitat quality for species of interest in order to assess the true value of the site to
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wildlife. Restoration of more natural vegetation around the creek channel would improve habitat
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value both within and around the stream by providing increased habitat and forage opportunities
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for terrestrial wildlife and by reducing soil erosion and water temperatures in the stream itself
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(Bond and Lake 2003).
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LITERATURE CITED
Allmendinger, N. 2005 The Cullowhee Creek Stream Enhancement Project. From Western
Carolina University Department of Geology:
http://www.wcu.edu/as/GeosciencesNRM/Geology/allmendinger/restoration.html
Bond, N. R. and P. S. Lake 2003. Local habitat restoration in streams: Constraints on the
effectiveness of restoration for stream biota. Ecological Management and Restoration 4:
193-198.
Lake, P. S. 2001. Restoring streams: re-building and reconnecting. In Third Australian Stream
Management Conference 369-371.
Palmer, M. A., R. F. Ambrose, and L. N. Poff. 1997. Ecological theory and community
restoration. Restoration Ecology 5: 291-300.
Smokorowski, K. E., K. J. Withers, and J. R. Kelso. 1998. Doest habitat creation contribute to
management goals? An evaluation of documenting habitat rehabilitation or enhancement
projects. Canadian Technical Report of Fisheries and Aquatic Sciences. Number 2249.
United States Department of Agriculture. 1997. Soil Survey of Jackson County, North Carolina.
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