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Fisheries Survey of the BosqueRiver Watershed Above Lake
Waco
March through May 1998
Tim Jones
TIAER PR0005
May 2000
Texas Institute for Applied Environmental ResearchTarleton State
University •Box T0410 •Tarleton Station •Stephenville, Texas
76402V254.968.9567 • F254.968.9568
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Fisheries Survey of the Bosque River Watershed Above Lake
Waco
Acknowledgments
The research on which this report is based was financed in part
by the U.S. Department of Agriculture Natural Resources
Conservation Service.
This work was performed under the general supervision of Ron
Jones, Texas Institute for Applied Environmental Research (TIAER)
Director, and Dr. Larry Hauck, Assistant Director for Environmental
Sciences. The data collection program was designed and implemented
by Tim Jones, Senior Research Associate. Data were collected by
Jeff Stroebel, Senior Research Assistant; John Thiebaud and Todd
Adams, Research Assistants, and Gary Kendall, Chris Pearson and
Gary Prichard, Research Technicians. William Ross, Research
Assistant, produced the map. TIAER Media staff provided graphics
and final formatting. Editing was provided by Dr. Hauck and Dr.
Richard Kiesling, Research Scientist. Statistical analysis
supervision was provided by Dr. Anne McFarland, Research
Scientist.
Finally, TIAER acknowledges the support from landowners who
allowed access through their property for monitoring. Without the
willing cooperation of these landowners, this study would not have
been possible.
2
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Fisheries Survey of the Bosque River Watershed Above Lake
Waco
Abstract
From March 1998 through May 1998 field personnel from the Texas
Institute for Applied Environmental Research (TIAER) sampled the
fish populations at nine sites located in the Bosque River
watershed above Lake Waco. This study was performed to compare
present population assemblages with historical data and to
determine degree of impairment.
At each site, habitat evaluations were performed, water quality
parameters were recorded, and fish species were collected.
Twenty-six total fish species were identified. When feasible,
identifications were performed in the field and fish were released.
However, when field identifications were not possible, specimens
were preserved in 10 percent formalin and returned to the lab.
Data analysis included a species diversity index ( ), an index
of biotic integrity (IBI), an index of similarity and a habitat
quality index (HQI). Data suggest that habitat necessary to support
a diversity of aquatic life is adequate but not optimal. The HQI
for eight sites scored intermediate, while one scored limited. IBI
scores ranged from fair to good, generally correlating to HQI
scores. No sites yielded a poor or lower IBI rating; conversely, no
site was rated exceptional. Scores ranged from fair (6 sites) to
good (2 sites) while one site fell between the two. Species
diversity ( ) for all sites fell with the range (1-3) described by
Wilham and Dorris (1968) as indicative of moderate pollution. No
direct statistical correlation was found between IBI scores and
water quality.
H
H
3
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Fisheries Survey of the Bosque River Watershed Above Lake
Waco
4
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Contents
Chapter 1 Fisheries Survey of the Bosque River Watershed Above
Lake Waco . . . . . . . 11Introduction . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . 11Study Sites . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Site Descriptions . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . 12Materials and Methods . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . 15
Habitat Evaluation and Fish Sampling . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15Data
Analysis . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . 23Results . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . 24
Water Quality Parameters. . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
24Habitat Results . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . 27Fisheries Results . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . 28
Discussion . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . 36Conclusions . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . 38
Appendix A Trophic Feeding Group and Tolerance Classifications
of Fish . . . . . . . . . . 39
Appendix B Index of Biotic Integrity Scores . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . 41
Appendix C Physiochemical Data . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
Appendix D Habitat Quality Index Score Sheets . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . 59
References . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . 79
5
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Fisheries Survey of the Bosque River Watershed Above Lake
Waco
6
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Tables
Table 1 Scoring criteria used for rating the index of biotic
integrity (IBI) of the Bosque River . . . . 22Table 2
Physiochemical measurements collected at each sampling site . . . .
. . . . . . . . . . . . . . . . . . . 25Table 3 Mean water quality
values for routine grabs . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . 26Table 4 Habitat score for
each site based on HQI . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . 28Table 5 Diversity Index .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28Table 6
Comparison of multiple agency IBI scores at common sites . . . . .
. . . . . . . . . . . . . . . . . . . . . 29Table 7 Index of
similarity between sites . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
Table 8 All fishes collected from the Bosque River watershed
(Spring 1998) . . . . . . . . . . . . . . . . . . . 30Table 9 Index
of biotic integrity summary table of fishes collected in the Bosque
River . . . . . . . . . 35
Table A–1 Trophic feeding group and tolerance classification of
fish . . . . . . . . . . . . . . . . . . . . . . . . . . 40
Table B–1 Total IBI score . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . 43
Table C–1 bo020—24-hour deployment . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . 45Table C–2 bo020—1-year biweekly grabs . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . 46Table C–3 bo040—24-hour deployment . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . 47Table C–4 bo040—1-year biweekly grabs . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . 48Table C–5 bo070—24-hour deployment . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . 49Table C–6 bo070—1-year biweekly grabs . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . 50Table C–7 gc100—24-hour deployment . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . 51Table C–8 gc100—One year biweekly
grabs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . 52Table C–9 mb060—24-hour
deployment . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . 53Table C–10
hc060—24-hour deployment . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54Table
C–11 nc060 — 24-hour deployment . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
55Table C–12 bo100 — 24-hour deployment . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . 56Table C–13 sb060 — 24-hour deployment . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . 57
7
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Fisheries Survey of the Bosque River Watershed Above Lake
Waco
8
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Figures
Figure 1 Sites selected for the survey . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . 13Figure 2 Habitat Quality Index (HQI) . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . 17Figure 3 Stream Physical Characteristics
Worksheet . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . 19
9
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Fisheries Survey of the Bosque River Watershed Above Lake
Waco
10
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Fisheries Survey of the BosqueRiver Watershed Above Lake
Waco
IntroductionFrom March 1998 through May 1998 field personnel
from the Texas Institute for Applied Environmental Research (TIAER)
sampled the fish populations at nine sites located in the Bosque
River watershed above Lake Waco. The survey was conducted to
compare present population assemblages with historical data and to
determine the degree of impairment. Findings reported from this
study will inform continuing efforts to understand water quality
conditions in the Bosque River watershed.
Assessment of water quality trends has historically relied on
the characterization of the chemical and physical integrity of
water bodies. While the degradation of the abiotic environment is a
major water quality concern, studies have shown that regular
monitoring of streams and rivers for chemical pollutants or
physical modifications will underestimate the severity of the
biological degradation of some waters. Comparative studies
conducted by the Ohio Environmental Protection Agency suggest that
monitoring programs based solely on the chemical characterization
of water bodies may underestimate the number of biologically
impaired water quality sites by 30 to 40 percent (Ohio EPA, 1987).
These failure rates can be improved significantly by incorporating
biological monitoring into the assessment methodology.
Biological monitoring provides the basis for the assessment of
the biological integrity of surface waters (EPA, 1990). Biological
integrity is a necessary condition for ecosystem health and the
third component of ecological integrity as defined by the Clean
Water Act. As such, it is an important regulatory component of
water quality. However, biological integrity is an even more
important ecological consideration.
Assessing biological integrity is challenging because of the
variable nature of aquatic communities. Methods have been developed
to reduce the complexity and compress the variation found in these
biological data. For example, Yoder and Rankin (1995) review how
Ohio EPA has addressed these concerns by compressing variation
through the use of multi-metric, evaluative indices such as the
index of biotic integrity (IBI) (Karr, 1986) and the invertebrate
community index (ICI) (Yoder and Rankin, 1995). These multimetric
indices of fish and aquatic benthic macroinvertebrate communities
provide the comparative analytical tools necessary to assess the
water quality status of receiving waters. This report outlines the
result of a comparative study of water quality within the Bosque
River watershed using the fish community index tool known as the
IBI. This report builds upon earlier work characterizing the
benthic macroinvertebrate community of the watershed (Hendon et
al., 1998) and supplements the characterization of chemical water
quality analysis of the same watershed (Pearson and McFarland,
1999).
11
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Fisheries Survey of the Bosque River Watershed Above Lake
Waco
Study SitesThe study area is in the Bosque River watershed above
Lake Waco. This area included Texas Natural Resource Conservation
Commission (TNRCC) stream segments 1226 (North Bosque River
approximately 100 meters upstream from Farm Road 185 to just above
the confluence of Indian Creek in Erath County), 1255 (North Bosque
River from the confluence of Indian Creek to the confluence of the
North Fork and South Fork of the North Bosque River) and 1246 (the
Middle and South Bosque Rivers). The nine sites (Figure 1) selected
for fish sampling coincide with sites where TIAER operates
automated storm water sampling stations and conducts routine,
biweekly water quality assessments. Additionally, Dr. Marty
Matlock, Department of Agricultural Engineering, Texas A&M
University, adopted these sites for deployment of periphytometers,
instruments used in assessing the effects of nutrients on the
periphyton populations. Historical fish survey data exist for
several of these sites from collections performed by the Brazos
River Authority (BRA) (1998), Texas Water Commission (TWC) (1992),
and Texas Parks and Wildlife Department (TPWD) (Linam and
Kleinsasser, 1987).
Sites selected for the survey included:
• bo020—North Bosque River at State Highway 8 in north
Stephenville, Erath County, Texas
• bo040—North Bosque River at Erath County Road 454, ¼-mile
below the City of Stephenville Wastewater Treatment Plant effluent
outfall
• bo070—the North Bosque River at Hico City Park, Hamilton
County, Texas
• bo100—North Bosque River at Farm Road 56 near Valley Mills,
Bosque County, Texas
• gc100—Green Creek at Erath County Road 266 in Clairette, Erath
County, Texas
• nc060—Neils Creek at State Highway 6 in Bosque County,
Texas
• hc060—Hog Creek at Farm Road 185 in McLennan County,
Texas,
• mb060—Middle Bosque River at Farm Road 185 in McLennan County,
Texas
• sb060—South Bosque River at U.S. Highway 84 in McLennan
County, Texas
Site Descriptions
bo020
This site was characterized by intermittent flow with perennial
pools and moderate sinuosity. Debris on stream banks and personal
observations indicated extreme flow fluctuations result in scouring
and steam bed modification. Within the reach examined, stream
characteristics included width ranging from 13 to 32 feet, a
maximum depth of 3.7 feet and a mean depth of 1.2 feet. Presence of
cobble and gravel substrate provided suitable instream cover for
fish. Although no secondary channel alteration was apparent, bank
erosion potential during high flow existed. Riparian zone width
averaged 28 feet and was bounded on all sides by improved pasture.
Urban influences reduced the aesthetic qualities of this site.
12
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Fisheries Survey of the Bosque River Watershed Above Lake
Waco
Figure 1 Sites selected for the survey
bo040
This site was perennially influenced by effluent from the
Stephenville Wastewater Treatment Plant. The segment investigated
consisted of two well-developed riffles, two long moderately deep
pools, and moderate sinuosity. Stream characteristics included
width ranging from 14 to 42 feet, a maximum measured depth of 2.4
feet, and a mean depth of 1.1 feet. Although dominated by bedrock,
undercut banks and large submerged ledges provided suitable fish
habitat in pools. Riffle, glide, and run areas were characterized
by substrate ranging from gravel to boulder in size that provided
adequate instream cover for fish species. No secondary channel
alteration was observed but erosion potential during high flows was
evident. Riparian width averaged 42 feet, being bounded by improved
pasture used for hay and cattle grazing. The county road crossing
provided access to the stream, thus allowing dumping to occur with
relative ease. Items observed in the stream ranged from household
garbage to dead livestock. (At the time of sampling, a dead calf
was observed in the stream.) These items contributed to reduced
aesthetic quality at this site.
13
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Fisheries Survey of the Bosque River Watershed Above Lake
Waco
bo070
At this location, the North Bosque River is a perennial stream
although flows approaching zero have been observed. A long, shallow
pool extended downstream from the U.S. Highway 281 bridge to the
Hico City Park and terminated as a well-developed, though unstable,
riffle. Downstream of the park, the river flowed through a series
of pools and riffle/runs, although the channel was mostly straight.
Undercut banks, large submerged boulders, submerged logs and pebble
to cobble substrate provided suitable fish habitat. Stream
characteristics included width ranging from 38 to 60 feet, a
maximum depth of 3.1 feet, and a mean depth of 1.5 feet. Although
the riparian buffer was greater than 100 feet at some transects,
the average width was 55 feet. Human disturbances dominated this
site, such as residential and commercial development, a developed
park, and row crop agriculture lined the bank.
bo100
This site was furthest downstream from the North Bosque River
sampled above Lake Waco. The river at this site is perennial, with
large deep pools characterized by shifting sand to gravel substrate
that provided poor habitat for many fish species. Four riffles
within the area sampled, though relatively small, were dominated by
gravel to cobble substrate, providing suitable habitat for species
preferring this environment. Stream characteristics included width
ranging from 49 feet to 106 feet, a maximum depth of 5.75 feet, and
an average depth of 2.6 feet. Severe flow fluctuations were
evidenced by debris and large areas of exposed soil along steep
banks that created a potential for acute erosion. Vegetation below
the lip of the stream bank was rare. The width of the riparian
buffer averaged approximately 90 feet and was bounded on all sides
by improved pasture. Aesthetically, this area appeared natural,
though evidence of limited human use was observed.
gc100
Green Creek, a large tributary of the upper North Bosque River
(UNBR) that drains the west side of Erath County, is characterized
as intermittent with perennial pools. Several large, deep pools,
well developed riffles, and moderate sinuosity combined with gravel
to cobble instream cover to provide suitable habitat for several
fish species. Stream characteristics included width ranging from 21
to 35 feet, a maximum depth of 3.5 feet, and a mean depth of 1.5
feet. Unvegetated stream banks contributed to severe erosion
potential during high flow events. Except near the county road, the
riparian buffer ranged from 150 to greater than 500 feet.
Aesthetically, this site was considered natural, as little human
disturbance was evident.
nc060
Listed as a least disturbed stream for Ecoregion 29 (TWC, 1992),
in which the Bosque River watershed is located, Neils Creek is
intermittent with perennial pools, numerous well developed riffles,
and strong sinuosity. Patches of bedrock were observed to be
interrupted by riffles characterized by gravel to cobble substrates
providing suitable habitat for fish species. Stream characteristics
included width ranging from 14 to 68 feet, a maximum depth of 3.4
feet, and an average depth of 1.3 feet. Debris along the bank
indicated severe flow fluctuations; however, vegetation on the
banks appeared to reduce the potential of extreme erosion. The
riparian buffer averaged 80 feet and was bordered on each side by
improved pasture. In spite of a major state highway transecting
this stream, the aesthetic quality of this area was classified as
natural.
14
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Fisheries Survey of the Bosque River Watershed Above Lake
Waco
hc060
At FM 185, Hog Creek is a perennial stream with pools dominated
by bedrock. Small amounts of gravel were observed in pockets
creating riffles that were unstable and inadequate as habitat for
most aquatic organisms, particularly fish. Macrophytes in the
riffle/run areas and attached algae provided the majority of
instream cover at this site. Submerged logs and undercut banks in a
large pool, created by a man-made dam, provided adequate habitat
for several fish species. Severe flow fluctuations have been
observed during the periods of storm water runoff monitored by
TIAER staff. However, the stream banks were well vegetated and
erosion potential was not as severe as other sites monitored.
Stream characteristics included width ranging from 32 to 63 feet, a
maximum depth of 2.6 feet, and an mean depth of 0.95 feet.
Residential development existed and cattle were observed in the
stream upstream from FM 185. The riparian buffer averaged 80 feet.
Aesthetically, this area was classified as common because of
development.
mb060
This stream site on the Middle Bosque River, although
aesthetically pleasing, was sparse of suitable fish habitat and
characterized by a generally straight channel, bedrock substrate,
limited riffles and intermittent stream flow. Severe flow
fluctuations, determined from observing debris line on stream bank,
and limited riparian vegetation indicated a potential for erosion
and instability. Stream characteristics included width ranging from
40 to 82 feet, a maximum depth of 1.45 feet, and a mean depth of
0.75 feet. Little evidence of human disturbance existed, although a
small herd of calves had been observed near the stream on
occasion.
sb060
The South Bosque River is generally perennial; however, during
the late summer of 1998, flow was observed to cease throughout most
of the drainage basin. At the location sampled, a large pool
approximately 0.5 miles long was bounded by short, narrow riffles.
The pool substrate consisted primarily of bedrock covered with silt
and sand. Undercut banks, submerged vegetation, and tree trunks and
limbs provided the majority of instream cover at this location,
resulting in suitable habitat for several fish species. The
riffles, dominated with gravel to cobble sized substrate, also
provided suitable fish habitat. Debris along the shoreline and
personal observation indicated severe flow fluctuations; however,
dense riparian vegetation renders protection from severe erosion
along most of the stream reach sampled. Stream characteristics
included width ranging from 9 to 44 feet, a maximum measured depth
of 2.75 feet, and a mean depth of 1.1 feet. Though evidence of
human disturbance existed, primarily litter and a parking area for
fishermen, the reach upstream from U.S. Highway 84 was classified
as natural. The riparian buffer, except at the highway crossing,
generally exceeded 300 feet.
Materials and Methods
Habitat Evaluation and Fish SamplingHabitat of each site was
ranked as part of a categorical analysis using the habitat quality
index (HQI) instrument (Figure 2) developed by the Texas Water
Commission (TWC, 1992). This tool examines a variety of habitat
parameters (Instream Cover, Pool Depth, Bank Stability,
Riparian
15
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Fisheries Survey of the Bosque River Watershed Above Lake
Waco
Cover, Flow Fluctuation, Channel Sinuosity, Bottom Substrate,
and Aesthetics), allowing field personnel to evaluate the
suitability of the habitat for occupancy by aquatic organisms. Each
of the above parameters are scored from either 0 to 4 or 0 to 3,
for a possible total of 30 points. Once scores are tabulated, sites
are classified into one of four categories defined by the HQI
instrument.
At each site, five cross sections were selected to represent
each of the following habitats: riffle, run, glide, and pool. The
length of streams evaluated ranged from 0.25 to 0.75 miles
depending on the availability of habitat at each site. Generally,
the section surveyed was bounded at its upper and lower limits by a
riffle. To assess each habitat type, more than one riffle, pool,
glide or run may have been contained within the selected
boundaries. At each cross section, width, slope, percent erosion,
depth (at least 10 points across the cross section), velocity (at
the same interval), substrate type, instream cover,
algae/macrophyte abundance and riparian buffer width were
evaluated. Velocity measurements were later converted to flow.
Additionally, general information about each site was recorded on a
data form Figure 3 including stream type, stream bends, number of
riffles, flow fluctuation, channel modifications, types, and
percentage of dominant riparian vegetation and aesthetics. Data
from these evaluations were used in developing a habitat score for
each site.
Exceptional 30 - 26
High 25 - 21
Intermediate 20 - 15
Limited < 14
16
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Fisheries Survey of the Bosque River Watershed Above Lake
Waco
Figu
re 2
Hab
itat
Qua
lity
Inde
x (H
QI)
Ratin
g Pa
ram
eter
Attr
ibut
es o
f Sub
cate
gorie
s (Ra
ting
Scor
e)Sc
ore
Inst
ream
cove
rC
omm
on (>
50%
)
(4)
Occ
asio
nal (
30-5
0%)
(3)
Rar
e (1
0-30
%)
(2)
Non
e (<
10%
)
(0)
Rif
fles
Com
mon
(> 5
riff
les)
(4)
Occ
asio
nal (
2-4
riff
les)
(3)
Rar
e (1
rif
fle)
(2)
Non
e
(0)
Pool
dep
thL
arge
and
dee
pM
axim
um p
ool d
epth
> 4
ft.
(4)
Mod
erat
eM
axim
um p
ool d
epth
> 2
-4 ft
.
(3)
Smal
lM
axim
um p
ool d
epth
> 1
ft.
(2)
Non
eN
o ex
isti
ng p
ools
onl
y sh
allo
w a
uxili
ary
pock
ets
(1)
Ban
k st
abili
tySt
able
Lit
tle
evid
ence
(< 1
0%) o
f er
oded
ban
ks s
ide
slop
es
gene
rally
<30
o
(3)
Mod
erat
ely
stab
leSo
me
evid
ence
(11-
30%
) of
erod
ed b
anks
; sm
all a
reas
of
eros
ion
mos
tly
heal
ed o
ver.
Sid
e sl
opes
up
to 4
0o o
n on
e ba
nk
(2)
Mod
erat
ely
unst
able
Mod
erat
e fr
eque
ncy
(31-
50%
) an
d s
ize
of e
rod
ed a
reas
. Sid
e sl
opes
up
to 6
0o o
n so
me
bank
s
(1)
Uns
tabl
eL
arge
and
freq
uent
(< 5
0%)
erod
ed a
reas
. Raw
are
as
freq
uent
alo
ng s
teep
ban
ks;
sid
e sl
opes
>60
o
(0)
Rip
aria
n co
ver
Ext
ensi
veW
idth
of n
atu
ral c
over
>
350
ft.
(3)
Wid
eW
idth
of n
atu
ral c
over
15
0-35
0 ft
.(2
)
Mod
erat
eW
idth
of n
atu
ral c
over
15
-150
ft.
(1)
Nar
row
Wid
th o
f nat
ural
cov
er
> 1
5 ft
.(0
)
17
-
Fisheries Survey of the Bosque River Watershed Above Lake
Waco
Fig
ure
2: H
abit
at Q
ual
ity
Ind
ex (H
QI)
(con
tinu
ed)
Ratin
g At
trib
utes
of S
ubca
tego
ries (
Ratin
g Sc
ores
)Sc
ore
Flow
fluc
tuat
ions
Min
orLi
ttle
or
none
from
bas
e fl
ow
(3)
Mod
erat
eE
vid
ence
of d
ebri
s al
ong
mid
dle
por
tion
of b
anks
(2)
Seve
reE
vid
ence
of d
ebri
s hi
gh o
n ba
nks
(0)
Seve
re in
term
itte
nt s
trea
m
(0)
Cha
nnel
si
nuos
ity
Hig
h>
2 w
ell d
efin
ed o
utsi
de
bend
s w
ith
deep
out
sid
e ar
eas
and
shal
low
insi
de
area
s
(3)
Mod
erat
e1-
2 be
nds
wit
h at
leas
t one
be
nd w
ell d
efin
ed
(2)
Low
1-2
poor
ly d
efin
ed o
utsi
de
bend
s; s
light
mea
nder
ing
wit
h m
odif
ied
ben
ds
(1)
Non
est
raig
ht c
hann
el; m
aybe
ch
anne
lized
(0)
Bot
tom
su
bstr
ate
Stab
le50
% c
obbl
es, r
ubb
le o
r gr
ave
(3)
Mod
erat
ely
stab
le31
-50%
gra
vel o
r la
rger
su
bstr
ate
(2)
Mod
erat
ely
unst
able
10-3
0% g
rave
l or
larg
er
subs
trat
e
(1)
Uns
tabl
eBo
ttom
uni
form
san
d, c
lay,
silt
or
bed
rock
(0)
Aes
thet
ics
Wild
erne
ssO
utst
andi
ng n
atur
al b
eaut
y;
usua
lly w
ood
ed o
r unp
astu
red
area
; wat
er c
lari
ty e
xcep
tion
al
(3)
Nat
ural
are
aTr
ees
and
/or
nati
ve v
ege-
tati
on c
omm
on; s
ome
dev
elop
men
t evi
den
t (fr
om
fiel
ds,
pas
ture
s, d
wel
lings
); w
ater
cla
rity
dis
colo
red
(2
)
Com
mon
set
ting
Not
off
ensi
ve, d
evel
oped
but
un
clu
tter
ed; w
ater
may
be
colo
red
to tu
rbid
(1)
Off
ensi
veSt
ream
doe
s no
t enh
ance
ae
sthe
tics
; clu
tter
ed, h
ighl
y d
evel
oped
, du
mpi
ng a
rea;
w
ater
dis
colo
red
(0)
Tota
l sco
re fo
r al
l su
bcat
egor
iesa
a. K
ey to
HQ
I Sco
res:
30
–26
exce
ptio
nal
25–2
1 hi
gh20
–15
inte
rmed
iate
>14
limit
ed
TNR
CC
-WQ
S - H
QI_
PHY
S.T
B2
Rev
ised
06/
26/
97P
rint
ed S
epte
mbe
r 23
, 199
7
18
-
Fisheries Survey of the Bosque River Watershed Above Lake
Waco
Figu
re 3
Stre
am P
hysi
cal C
hara
cter
isti
cs W
orks
heet
Obs
erve
rs:_
____
____
____
____
____
____
Dat
e:__
____
____
____
_ Ti
me:
____
____
____
___
Wea
ther
con
diti
ons:
____
____
____
____
____
____
____
____
____
___
Stre
am:_
____
____
____
____
____
____
___
Loc
atio
n of
Sit
e___
____
____
____
____
____
____
___L
engt
h of
str
eam
eva
luat
ed:_
____
____
____
____
____
____
____
Wit
hin
Stre
am S
egm
ent N
o.: _
____
__ O
bser
ved
Str
eam
Use
s:__
____
____
____
____
____
____
____
____
____
____
____
____
____
____
____
____
____
____
____
_A
esth
etic
s (c
ircl
e on
e): (
1) w
ilder
ness
(2) n
atur
al (3
) com
mon
(4) o
ffen
sive
St
ream
Typ
e (c
ircl
e on
e): p
eren
nial
or
inte
rmit
tent
w p
eren
nial
poo
lsSt
ream
Ben
ds:
No.
Wel
l Def
ined
____
_; N
o. M
oder
atel
y D
efin
ed__
___;
No.
Poo
rly
Def
ined
____
__
Cha
nnel
Obs
truc
tion
s/M
odif
icat
ions
:___
____
____
____
____
____
No.
of R
iffle
s: _
____
____
Flo
w F
luct
uati
ons
(cir
cle
one)
: min
orm
oder
ate
seve
reE
vide
nce
of F
low
Flu
ctua
tion
s: _
____
____
Rip
aria
n V
eget
atio
n(%
): Tr
ees_
___
Shru
bs__
___
Gra
sses
, For
bes
____
___
Cul
t. Fi
eld
s___
____
_ O
ther
___
____
Loca
tion
of Tr
anse
ctSt
ream
Wid
th (f
t.)Le
ft B
ank
Slop
e (o
)Le
ft B
ank
Eros
ion
(%)
Stre
am D
epth
s (ft
.) at
Poi
nts A
cros
s Tra
nsec
tRi
ght B
ank
Slop
e (o
)Ri
ght B
ank
Eros
ion
(%)
Tree
Ca
nopy
(%)
Stre
am T
ype
(Cir
cle
One
) R
un
Rif
fle
Glid
ePo
olD
omin
ant S
ubst
rate
Typ
eD
omin
ant T
ypes
of R
ipar
ian
Veg
etat
ion:
% G
rave
l or
Lar
ger
Alg
ae/M
acro
phyt
e (C
ircl
e O
ne)
Abu
ndan
tC
omm
onR
are
Abs
ent
Wid
th o
f Rip
aria
n B
uffe
r V
eget
atio
n (f
t.)In
stre
am C
over
Typ
es:
% In
stre
am C
over
Loca
tion
of Tr
anse
ctSt
ream
Wid
th (f
t.)Le
ft B
ank
Slop
e (o
)Le
ft B
ank
Eros
ion
(%)
Stre
am D
epth
s (ft
.) at
Poi
nts A
cros
s Tra
nsec
tRi
ght B
ank
Slop
e (o
)Ri
ght B
ank E
rosio
n (%
)Tr
ee
Cano
py (%
)
Stre
am T
ype
(Cir
cle
One
) R
un
Rif
fle
Glid
ePo
olD
omin
ant S
ubst
rate
Typ
eD
omin
ant T
ypes
of R
ipar
ian
Veg
etat
ion:
% G
rave
l or
Lar
ger
Alg
ae/M
acro
phyt
e (C
ircl
e O
ne)
Abu
ndan
tC
omm
onR
are
Abs
ent
Wid
th o
f Rip
aria
n B
uffe
r V
eget
atio
n (f
t.)In
stre
am C
over
Typ
es:
% In
stre
am C
over
19
-
Fisheries Survey of the Bosque River Watershed Above Lake
Waco
Figu
re 3
: Str
eam
Phy
sica
l Cha
ract
eris
tics
Wor
kshe
et (
cont
inue
d)
Loca
tion
of Tr
anse
ctSt
ream
Wid
th (f
t.)Le
ft B
ank
Slop
e (o
)Le
ft B
ank
Eros
ion
(%)
Stre
am D
epth
s (ft
.) at
Poi
nts A
cros
s Tra
nsec
tRi
ght B
ank
Slop
e (o
)Ri
ght B
ank
Eros
ion
(%)
Tree
Ca
nopy
(%)
Stre
am T
ype
(Cir
cle
One
) R
un
Riff
leG
lide
Pool
Dom
inan
t Sub
stra
te T
ype
Dom
inan
t Typ
es o
f Rip
aria
n V
eget
atio
n:%
Gra
vel o
r L
arge
rA
lgae
/M
acro
phyt
e (C
ircl
e O
ne)
Abu
ndan
tC
omm
onR
are
Abs
ent
Wid
th o
f Rip
aria
n Bu
ffer
Veg
etat
ion
(ft.)
Inst
ream
Cov
er T
ypes
:%
Inst
ream
Cov
er
Loca
tion
of Tr
anse
ctSt
ream
Wid
th (f
t.)Le
ft B
ank
Slop
e (o
)Le
ft B
ank
Eros
ion
(%)
Stre
am D
epth
s (ft
.) at
Poi
nts A
cros
s Tra
nsec
tRi
ght B
ank
Slop
e (o
)Ri
ght B
ank
Eros
ion
(%)
Tree
Ca
nopy
(%)
Stre
am T
ype
(Cir
cle
One
) R
un
Riff
leG
lide
Pool
Dom
inan
t Sub
stra
te T
ype
Dom
inan
t Typ
es o
f Rip
aria
n V
eget
atio
n:%
Gra
vel o
r L
arge
rA
lgae
/M
acro
phyt
e (C
ircl
e O
ne)
Abu
ndan
tC
omm
onR
are
Abs
ent
Wid
th o
f Rip
aria
n Bu
ffer
Veg
etat
ion
(ft.)
Inst
ream
Cov
er T
ypes
:%
Inst
ream
Cov
er
Loca
tion
of Tr
anse
ctSt
ream
Wid
th (f
t.)Le
ft B
ank
Slop
e (o
)Le
ft B
ank
Eros
ion
(%)
Stre
am D
epth
s (ft
.) at
Poi
nts A
cros
s Tra
nsec
tRi
ght B
ank
Slop
e (o
)Ri
ght B
ank
Eros
ion
(%)
Tree
Ca
nopy
(%)
Stre
am T
ype
(Cir
cle
One
) R
un
Riff
leG
lide
Pool
Dom
inan
t Sub
stra
te T
ype
Dom
inan
t Typ
es o
f Rip
aria
n V
eget
atio
n:%
Gra
vel o
r L
arge
rA
lgae
/M
acro
phyt
e (C
ircl
e O
ne)
Abu
ndan
tC
omm
onR
are
Abs
ent
Wid
th o
f Rip
aria
n Bu
ffer
Veg
etat
ion
(ft.)
Inst
ream
Cov
er T
ypes
:%
Inst
ream
Cov
erTN
RC
C-W
QS
hqi_
phys
.tbl
Rev
ised
11/
13/
96Pr
inte
d N
ovem
ber
13, 1
996
20
-
Fisheries Survey of the Bosque River Watershed Above Lake
Waco
Fish were collected from March 2 - 5 and on May 13, 15, 19, 21
and 22, 1998. The gap from March to May resulted from an extremely
large rainfall event that occurred on March 15, 1998. This storm
caused extensive flooding and water levels remained elevated for
several weeks, making fish monitoring unfeasible until levels
subsided.
Methods of fish collection included backpack electroshock,
seining and, where water depth allowed, setting a gill net. Each
habitat type listed above was sampled with the gear-type most
suited for the habitat.
Electrofishing was performed using a Smith-Root, Inc. Model 12-B
Backpack Electrofisher.TM1 All types of stream habitats were
sampled with the electroshocker to a maximum depth of approximately
three feet. One field person shocked while two others collected the
stunned fish using dip nets. Electrofishing was performed for a
minimum of 15 minutes as described in the TNRCC Receiving Waters
Assessment Manual (TNRCC, 1997). Seining was performed in riffle,
run and glide areas as a supplement to electrofishing. The seine
used for sampling measured 4.9 m long, 1.8 m deep with 3.1mm ace
mesh. Habitats were seined in 10 meter intervals for a minimum of
60 meters until no new species were observed (TNRCC, 1997).
Experimental gill nets were used to collect large, pelagic
species not susceptible to seining or electroshocking. These nets
were 2-m deep consisting of six 8-m long panels with monofilament
stretched webbing of 25 mm, 38mm, 51mm, 64mm, 76mm and 89mm. Gill
nets were set at three sites (Green Creek, the North Bosque River
at FM 53 and the South Bosque River) where pool length and depth
were sufficient to allow the deployment of the net. Except at the
South Bosque River site, the gill net was deployed for at least 12
hours. Fishing traffic at the South Bosque River site jeopardized
leaving the net unattended for an extended period; therefore, the
net was deployed for approximately four hours.
Larger fish and many smaller individuals were identified,
measured (in mm) in the field and released. Fish not identified in
the field were preserved in 10 percent formalin and returned to the
lab for identification and measurement. All fish were examined
externally for condition, lesions, tumors, fin degradation, and
external parasites. Taxonomic references included Hubbs et al.
(1991), Blair et al. (1968) and Page and Burr (1991).
Dissolved oxygen (DO in mg/L), pH (standard units), water
temperature (°C) and specific conductance (µmhos/cm) were recorded
in situ for a period of 24-hours by deploying a Hydrolab Recorder
logging datasonde at each site. At some time during the deployment,
biological sampling occurred. Velocity was measured with a Global
Water Flow-Probe and converted to flow using software created
in-house by TIAER staff.
1 Mention of trade names or equipment manufacturers does not
represent endorsement of these products or manufacturers by
TIAER.
21
-
Fisheries Survey of the Bosque River Watershed Above Lake
Waco
Tab
le 1
Scor
ing
crit
eria
use
d fo
r ra
ting
the
inde
x of
bio
tic
inte
grit
y (I
BI)
of t
he B
osqu
e R
iver
Cate
gory
Met
ricSc
orin
g Cr
iteria
53
1Sp
ecie
s ri
chne
ss a
nd
com
posi
tion
1To
tal n
umbe
r of
fish
spe
cies
a
a. T
hird
ord
er s
trea
ms:
> 9
(5),
8-4
(3),
< 3
(1)
b
b. F
ourt
h or
der
stre
ams:
> 1
2 (5
), 11
-6 (3
), <
5 (1
)
c
c. F
ifth
ord
er s
trea
ms:
> 1
4 (5
), 13
-7 (3
), <
7 (1
)(L
inam
and
Kle
insa
sser
, 198
7)
2To
tal n
umbe
r of
dar
ter
spec
ies
> 2
10
3To
tal n
umbe
r of
sun
fish
spe
cies
> 2
1 - 2
04
Tota
l num
ber
of c
ypri
nid
spe
cies
oth
er th
an c
omm
on c
arp
> 3
3 - 2
0 - 1
5To
tal n
umbe
r of
into
lera
nt s
peci
es>
21
06
Prop
orti
on o
f ind
ivid
ual
s as
tole
rant
s<
5%5
- 20%
> 20
%
Trop
hic
com
posi
tion
7P
ropo
rtio
n of
ind
ivid
ual
s as
om
nivo
res
< 20
%20
- 45
%>
45%
8Pr
opor
tion
of i
ndiv
idu
als
as in
vert
ebra
te fe
eder
s>
80%
> 40
- 80
%<
40%
9Pr
opor
tion
of i
ndiv
idu
als
as p
isci
vors
5%5
- 1%
< 1%
Fish
abu
ndan
ce a
nd
cond
itio
n10
Num
ber
of in
div
idu
als
in s
ampl
e>2
00>5
0 - 2
00
0 - 1
%>
1%12
Pro
port
ion
of in
div
idu
als
as w
ith
dis
ease
or
othe
r an
omal
y<
2%>
2 - 5
%>
5%
22
-
Fisheries Survey of the Bosque River Watershed Above Lake
Waco
Data AnalysisSpecies diversity was calculated using two similar
species diversity index equations, as follows:
1. The equation proposed by Wilhm (1970) using log base 2 ( )
where diversity is calculated as:
2. A species diversity index proposed by Lind (1985) using
natural log (ln) where diversity is calculated as:
where
= species diversity,
= number of individuals in the species,
= number of individuals in the sample and
= number of species.
Generally, values less than 1 indicate severely degraded
conditions, 1-3 indicate moderately polluted streams and above 3
indicate clean water streams (Wilhm and Dorris, 1968).
Index of similarity, a measure of the degree of resemblance in
species composition between two sites, was calculated using the
following equation from Odum, (1971):
where
= index of similarity,
= the number of species in sample A,
= the number of species in sample B and
= the number of species common to both samples.
Values can range from zero, meaning the sites are totally
dissimilar, to 1.0, which indicates sites are identical in numbers
of species present.
An index of biotic integrity (IBI) is a multimetric tool used to
calculate the condition of a stream site based on zoogeographic,
ecosystem, community, population, and individual perspectives
(Plafkin et al., 1989). The IBI used in calculating stream
condition for this study was developed for Texas streams by Linam
and Kleinsasser (1987), as modified from the IBI developed by Karr
et al. (1986). The scoring criteria used in developing the IBI
score for each site sampled are depicted in Table 1. See Appendix
A, ”Trophic Feeding Group and Tolerance
2log
H ni n⁄( ) 2 ni n⁄( )log
i 1–
s
∑–=
H n1 n⁄( ) n1 n⁄( )ln
i 1–
s
∑–=
H
ni ith
n
s
S 2C( ) A⁄ B+=
S
A
B
C
23
-
Fisheries Survey of the Bosque River Watershed Above Lake
Waco
Classifications of Fish” for further information derived from
Linam and Keinsasser (1998). IBI integrity class scores and
attributes are listed in Appendix B, ”Index of Biotic Integrity
Scores”.
Results
Water Quality ParametersPhysical sampling site information and
mean values for physiochemical data collected from deployed logging
datasondes, unless otherwise noted, are presented in Table 2. Raw
physiochemical data appear in Appendix C, ”Physiochemical Data” and
include max., min. and median values. Dissolved oxygen (DO) values
recorded over a 24-hour (30-minute intervals) period during fish
sample collection are available only for sites bo100, nc060, hc060,
mb060 and sb060. DO values logged at sites bo020, bo040, bo070 and
gc100 were all well above saturation levels and deemed
questionable. Because pre- and post-calibration identified no
equipment malfunction, it was speculated that the original logging
frequency (10 minutes) was too short to allow the instrument
sufficient time to stabilize between sampling. Therefore, mean DO
values for sites bo020, bo040, bo070 and gc100 were calculated from
biweekly grab sampling data collected by TIAER during a 1-year
period prior to performing the fish monitoring. Mean values of
dissolved oxygen (DO), pH and water temperature did not appear to
be a limiting condition for the occurrence of aquatic life.
DO values recorded from the 24-hour deployment indicated that
hc060 yielded the lowest range, 3.94 to 6.06 mg/l, with a mean of
4.94 mg/l. The highest DO values recorded during a 24-hour
deployment were at sb060, ranging from 8.87 to 13.42mg/l, with a
mean of 10.42 mg/l. Generally, data (2-year mean) collected at
sites in the upper North Bosque River (bo020, bo040 and bo070) and
Green Creek (gc100) showed large variations in DO levels Table 3.
DO values above saturation (approximately 9 mg/l @ 20oC) were
recorded at all sites, while values below the criteria standard
were measured at all sites except bo100 and nc060. Data collected
at bo020 revealed the widest range of DO values of all sites (0.3
to 15.0 mg/l).
Historical mean water quality grab sample data, collected
biweekly from 1 January 1997 through 31 December 1998, are listed
in Table 3. Chlorophyll-a levels from these data reveal that
concentrations often exceed the TNRCC 16.5 µg/l screening level
(TNRCC, 1998) at all sites on the North Bosque River and Green
Creek. At the remaining sites (hc060, hc060, mb060 and sb060),
chlorophyll-a values exceeding this level were only recorded at
sb060 five percent of the time. The elevated chlorophyll-a values
at the North Bosque River sites and Green Creek suggest an
abundance of phytoplankton. This abundance of algae may influence
the range of DO values recorded at the North Bosque River sites and
Green Creek.
Additional, examination of the two year mean values for biweekly
grab samples Table 3 indicate that nitrate plus nitrite as nitrogen
(NO2+NO3-N) levels exceeded the screening levels presented by the
TNRCC only at sb060. Surprisingly, the mean chlorophyll-a value
calculated for this site (4.85 µg/l) did not approach the TNRCC
screening level. Mean values for all nutrient constituents
calculated for bo040 approached the screening levels but did not
exceed the values. However, Pearson and McFarland (1999) reported
individual nutrient values for biweekly grabs at bo040 exceeded the
TNRCC screening levels for NO2 + NO3-N (51 percent of the time),
ammonia (NH3-N, 31 percent), orthophosphate as phosphorous (PO4-P,
30 percent) and total phosphorous (Total-P, 30 percent). Each of
these parameters exceeded the TNRCC screening levels sufficiently
to be rated Not Supporting/Concern for supporting aquatic life. The
only other site yielding a less than Fully Supporting/No Concern
rating occurred at bo020.
24
-
Fisheries Survey of the Bosque River Watershed Above Lake
Waco
Tab
le 2
Phys
ioch
emic
al m
easu
rem
ents
col
lect
ed a
t eac
h sa
mpl
ing
site
Site
ID
Loca
tion
Data
sond
e Da
te:
Tim
e De
ploy
edCh
anne
l W
idth
Mea
n De
pth
Disc
harg
eM
ean
DOM
ean
pHM
ean
Tem
pM
ean
Cond
uctiv
ityCa
nopy
Co
ver
Drai
nage
Ar
ea
Nor
th B
osqu
e Ri
ver
ddm
myy
:hh:
mm
(ave
rage
in
m)
(m)
(m3 /
s)(m
g/L)
(0C)
(um
hos/
cm)
(mea
n%)
(mi.2
)
bo02
0 H
ighw
ay 8
N. S
teph
envi
lle02
Mar
98:0
0:30
03
Mar
98:0
0:00
6.6
0.37
11.1
87.
56a
a. 1
-yea
r av
erag
e fr
om b
iwee
kly
dat
a
8.36
8.84
1231
2383
.08
bo04
0E
rath
CR
454
02M
ar98
:14:
00
03M
ar98
:13:
308.
50.
349.
548.
13a
8.17
10.3
312
6021
99.1
1bo
070
U.S
. Hw
y 28
1 an
d H
ico
Cit
y Pa
rk04
Mar
98:1
6:00
05
Mar
98:1
5:30
14.9
0.46
76.5
59.
86a
8.26
14.5
176
08
359.
22bo
100
FM 5
6 ne
ar V
alle
y M
ills,
TX
20M
ay98
:14:
00
21M
ay98
:13:
3023
.60.
7995
.30
8.56
7.68
26.3
156
62
1166
.09
Gre
en C
reek
gc10
0 E
rath
CR
266
04M
ar98
:16:
00
05M
ar98
:15:
308.
50.
4622
.77
8.13
a8.
1814
.16
830
1310
1.00
Nei
ls C
reek
nc06
0 N
eils
Cre
ek a
t TX
SH
619
May
98:0
9:00
20
May
98:0
8:30
12.5
0.40
9.16
7.96
7.57
25.2
950
08
135.
60M
idd
le B
osqu
e C
reek
mb0
60FM
185
nea
r C
raw
ford
, TX
13M
ay98
:11:
00
14M
ay98
:10:
3018
.60.
237.
115.
507.
7124
.27
389
611
9.39
Hog
Cre
ekhc
060
FM 1
85 n
ear
Oce
e, T
X14
May
98:1
6:00
15
May
98:1
3:30
14.5
0.29
5.84
4.94
7.80
24.4
240
611
78.8
9So
uth
Bos
que
Riv
ersb
060
Sout
h B
osqu
e at
U.S
. Hw
y 84
20M
ay98
:13:
00
21M
ay98
:12:
308.
10.
342.
2810
.42
7.58
25.6
758
311
88.1
1
25
-
Fisheries Survey of the Bosque River Watershed Above Lake
Waco
Tab
le 3
Mea
n w
ater
qua
lity
valu
es fo
r ro
utin
e gr
abs
Janu
ary
1997
to D
ecem
ber
1998
Site
CHLA
(µ
g/L)
NH3-
N (m
g/L)
NO2+
NO3-
N (m
g/L)
PO4-
P (m
g/L)
TKN
(mg/
L)To
tal-P
(m
g/L)
Mea
n DO
a (m
g/L)
a. M
ean,
min
imum
and
max
imum
pro
vide
d fo
r D
O.
DO
(coe
f. va
r.) M
in D
O (m
g/L)
Max
DO
(mg/
L)
(TNR
CC
Scre
enin
g Le
vel)
(>16
.5 µ
g/L)
(>0.
3 m
g/L)
(>3.
1 m
g/L)
(>1.
4 m
g/L)
(>1.
6 m
g/L)
(> 4
.0 o
r 5.0
m
g/L)
(>4.
0 or
5.0
mg/
L)
bo02
041
.93
0.09
1.01
0.29
41.
670.
457.
10.
510.
315
.0bo
040
32.4
30.
232.
361.
112
1.83
1.56
7.9
0.37
3.2
14.3
bo07
042
.20
0.07
0.35
0.15
60.
940.
319.
80.
404.
916
.7bo
100
16.6
00.
050.
800.
032
0.64
0.13
9.3
0.27
6.1
14.9
gc10
035
.69
0.11
0.61
0.09
21.
030.
028.
20.
314.
413
.0nc
060
3.65
0.04
0.49
0.01
80.
300.
078.
90.
275.
012
.6hc
060
3.65
0.05
0.95
0.02
30.
430.
088.
70.
312.
913
.6m
b060
3.21
0.05
1.79
0.02
10.
040.
089.
50.
354.
015
.9sb
060
4.85
0.05
8.42
0.02
90.
560.
158.
00.
323.
412
.9
26
-
Fisheries Survey of the Bosque River Watershed Above Lake
Waco
for ammonia (NH3-N) which received a Partially
Supporting/Potential Concern rating. With the exception of NO2 +
NO3-N at sb060, the higher nutrient concentrations were generally
observed at sites of the UNBR watershed, i.e., bo020, bo040, bo070
and gc100.
Elevated DO levels, coupled with DO values recorded below the
screening level established by the TNRCC, may be an indicator of
potential threat to aquatic life. Although algae are commonly
recognized as producers of oxygen, it is not generally realized
that they are oxygen consumers as well. The threat that occurs
under bloom situations is that during hours of darkness
photosynthesis ceases and algae can deplete DO to levels lethal to
some aquatic species. This is particularly problematic during warm
months when the oxygen-carrying capacity of water is reduced,
stream flow is often low and calm winds diminish the potential for
oxygen diffusion into the water from the atmosphere. Consequently,
mortality of aquatic organisms may occur as these DO reducing
factors act together. Data recorded from sites bo020, bo040, hc060
and sb060 (Table 3) indicate that each site has yielded DO values
below the TNRCC minimum standard of 4 mg/l (TNRCC, 1998).
Additionally, the high coefficient of variance for DO data (0.51)
(Table 3) collected from bo020 indicates a high degree of
variability in DO levels at this site.
Values for pH (7.8 – 8.7), though highest at the North Bosque
River sites, were within the range (6.5 – 9.0) deemed suitable for
supporting aquatic life at all locations. Specific conductance
readings were also highest in the North Bosque River, especially at
bo020, above the City of Stephenville, and at bo040, below the City
of Stephenville wastewater treatment plant discharge. Linam and
Kleinsasser (1987) reported similar values below the WWTP outfall
and attributed this to be an influence of the treatment plant.
However, specific conductance values recorded at the Highway 8
bridge (above the WWTP outfall) during this study suggest other
influences, possibly from animal feeding operations (McFarland and
Hauck, 1995).
Though not measured using a Secchi disk, water transparency was
observed to be poorest in pools of the North Bosque River, Green
Creek and South Bosque River. The Middle Bosque River site had the
greatest transparency, as the substrate was visible at all
transects. Neils Creek was similar to the Middle Bosque River in
transparency, as TIAER field personnel were able to observe and
identify several individuals of large, pool habitants (Moxostoma
congestum and Carpiodes carpio) that were not susceptible to
seining or electroshock. Reduced transparency in the North Bosque
River correlates with the high levels of chlorophyll measured at
these sites which indicates an abundance of phytoplankton. Poor
transparency in the South Bosque River, however, cannot be
attributed to elevated populations of phytoplankton as mean
chlorophyll-a levels for the 3-months preceding the fish sampling
were very low (
-
Fisheries Survey of the Bosque River Watershed Above Lake
Waco
All sites scored low, 1–0, for flow fluctuations, as all are
subject to flow extremes. Lack of bank stability adversely impacted
scores at all sites except sb060. Diminished riparian cover reduced
the HQI scores for all except mb060 and sb060. HQI scores at sites
in the upper North Bosque River, bo020, bo040, bo070, were reduced
due to poor aesthetic quality. A lack of instream cover, which
affords shelter for small fish and habitat for species of
invertebrates that serve as a food source, rated poorly at bo070,
mb060 and bo100. Substrate, in conjunction with instream cover to
provide refuge, scored low at both nc060 and bo100. Both sites were
dominated by sand to gravel sized particles, which are constantly
shifting and altering habitat availability. Site mb060 scored lower
than all other sites in the parameters of pool depth and channel
sinuosity.
Fisheries ResultsAn index of diversity for this report was
calculated for each site sampled using log2 (Wilhem, 1970).
However, as ln is sometimes used (Lind, 1985), calculations using
this base were performed as well. Diversity index values for each
site using both equations are listed in Table 5, both for reference
and for comparison.
Results from the index of similarity calculation are shown in
Table 6. Scores calculated using the index of biotic integrity tool
for fish data collected by TIAER are depicted in Table 7.
Additionally, IBI scores calculated from historical data collected
by other agencies are listed for comparison. Information inTables 7
and 9 will be referred to in the following site-by-site
discussions.
.
Table 4 Habitat score for each site based on HQI
Site Habitat Score % of Possible Category
BO020 17 57 IntermediateBO040 17 57 IntermediateBO070 16 53
IntermediateBO100 17 57 IntermediateGC100 18 60 IntermediateNC060
19 63 IntermediateHC060 17 57 IntermediateMB060 14 47 LimitedSB060
20 67 Intermediate
Total Possible 30
Table 5 Diversity Index
Site log2 ln
bo020 2.10 1.45
bo040 2.67 1.84
bo070 1.20 0.83
bo100 1.70 1.17
gc100 2.99 2.07
nc060 2.70 1.87
hc060 2.79 1.93
mb060 2.07 1.43
sb060 2.99 2.06
28
-
Fisheries Survey of the Bosque River Watershed Above Lake
Waco
Fish species collected from the nine sites in the Bosque River
watershed are listed in Table 8. A total of 26 fish species were
identified, including two that are considered pollution intolerant,
the mimic shiner (Notropis volucellus) and the bigscale logperch
(Percina macrolepidia). The North Bosque River watershed (all sites
accumulative) and the South Bosque River each yielded 20 species of
fish, while 11 species were collected at Hog Creek and only nine in
the Middle Bosque River. Only the mimic shiner was collected from
the North Bosque River watershed (Neils Creek only), while both
pollution intolerants were collected from the South Bosque River.
No pollution intolerant species were identified from either Hog
Creek or the Middle Bosque River. Longear Sunfish (Lepomis
megalotis) which was common to all sites, was previously considered
intolerant, however, Linam and Kleinsasser (1998) have reclassified
the tolerance of this species as intermediate. Specimens of the
genus Micropterus are not reported as species. TIAER field
personnel desired to release, unharmed, as many individuals of this
genus as possible, and many were too small to clearly exhibit the
color patterns distinguishing spotted bass (M. punctulatus) from
largemouth bass (M. salmoides). Examination, which included
dissection, of the few individuals returned to the lab indicated
largemouth bass and spotted bass were present together in the
watershed.
Four earlier collections from at least one site common to this
study have been reviewed Table 7. A 1953 effort by Hubbs and Strawn
identified 20 species from the Bosque River. Only the dusky darter
(Percina sciera), reported in the 1953 study, was not collected in
this study. Nine species collected in this study that were not
reported in the 1953 collection include: Longnose gar (Lepisosteus
osseus), alligator gar (Lepisosteus spatula), gizzard shad
(Dorosoma cepedianum), common stoneroller (Campostoma congestum),
mimic shiner (Notropis volucellus), pugnose minnow (Opsopoedus
emiliae), river carpsucker (Carpiodes carpio), black bullhead
(Ameiurus melas) and inland silversides (Menidia beryllina).
Table 6 Index of similarity between sitesFish collected March
1998 through May 1998
Sites BO020 BO040 BO070 BO100 GC100 NC060 MB060 HC060 SB060
BO020 - - - - - - - - -BO040 0.75 - - - - - - - -BO070 0.78 0.70
- - - - - - -BO100 0.45 0.50 0.75 - - - - - -GC100 0.67 0.70 0.91
0.77 - - - - -NC060 0.70 0.64 0.75 0.71 0.75 - - - -MB060 0.53 0.55
0.60 0.58 0.50 0.73 - - -HC060 0.56 0.50 0.55 0.54 0.55 0.71 0.70 -
-SB060 0.52 0.62 0.58 0.57 0.52 0.73 0.55 0.63 -
Table 7 Comparison of multiple agency IBI scores at common
sitesa
a. (P/F = Poor to Fair, F = Fair, F/G = Fair to Good, G =
Good)
Site TIAER 1998 BRA 1997 TPW 1987 TNRCC 1991
bo020 40 F 38 P/F -bo040 40 F 42 F 42 Fbo070 40 F 46 F/G -bo100
46 F/G - -gc100 42 F 44 F -nc060 50 G - - 46 F/Ghc060 40 F - -mb060
40 F - 46 F/Gsb060 52 G - 48 G
29
-
Fisheries Survey of the Bosque River Watershed Above Lake
Waco
Tab
le 8
All
fish
es c
olle
cted
from
the
Bos
que
Riv
er w
ater
shed
(Spr
ing
1998
)
Taxa
Com
mon
Nam
ebo
020
bo04
0gc
100
bo07
0nc
060
bo10
0m
b060
hc06
0sb
060
Lep
isos
teus
oss
eus
Lon
gnos
e G
ar18
116
Lepi
sost
eus
spat
ula
Alli
gato
r G
ar1
Dor
osom
a ce
ped
ianu
mG
izza
rd S
had
7
Not
emig
onu
s ch
ryso
leu
cas
Gol
den
Shin
er3
Pim
ephl
as p
rom
elas
Fath
ead
Min
now
328
519
536
68
Pim
phal
es v
igila
xB
ullh
ead
Min
now
109
93
816
231
Cyp
rine
lla lu
tren
sis
Red
Shi
ner
6814
3192
79
1325
219
Cyp
rine
lla v
enus
taBl
ackt
ail S
hine
r21
214
109
552
5810
4
Not
ropi
s vo
luce
llus
Mim
ic S
hine
r13
81
Ops
opoe
du
s em
iliae
Pu
gnos
e M
inno
w1
Cam
post
oma
anam
olu
mC
omm
on S
tore
rolle
r2
Car
piod
es c
arpi
oR
iver
Car
psuc
ker
11
12
Mox
osto
ma
cong
estu
mG
rey
Red
hors
e60
4
Am
eiur
us n
atal
isYe
llow
Bul
lhea
d2
52
222
22
Am
eiu
rus
mel
isB
lack
Bul
lhea
d2
1
Icta
luru
s pu
ncta
tus
Cha
nnel
Cat
fish
34
313
425
1
Pyl
odic
tis o
livar
isFl
athe
ad C
atfi
sh2
43
4
Fund
ulu
s no
tatu
sBl
acks
trip
e To
p M
inno
w4
1
Gam
busi
a af
fini
sM
osqu
itof
ish
28
3
Men
idia
ber
yllin
aIn
land
Silv
ersi
des
3
Lepo
mis
cya
nellu
sG
reen
Sun
fish
5026
1450
99
5122
14
Lepo
mis
meg
alot
isLo
ngea
r Su
nfis
h15
3020
3212
2933
1748
Lep
omis
mac
roch
irus
Blue
gill
1323
206
11
12
10
Mic
ropt
eru
s sp
.B
ass
31
115
52
Ethe
osto
ma
spec
tabi
leO
rang
ethr
oat D
arte
r5
613
3562
Per
cina
mac
role
pid
iaBi
gsca
le L
ogpe
rch
2
Tota
l Ind
ivid
uals
161
114
141
1240
203
1971
344
193
664
30
-
Fisheries Survey of the Bosque River Watershed Above Lake
Waco
Linam and Kleinsasser (1987) sampled the North, Middle and South
Bosque Rivers above Lake Waco and reported 26 species of fish.
Species not collected in this study but reported in the 1987
sampling included: threadfin shad (Dorosoma petenense), warmouth
(Lepomis gulosus), orangespotted sunfish (L. humilis), dollar
sunfish (L. marginatus), redear sunfish (L. micropholus) spotted
sunfish (L. punctatus) and white crappie (Pomoxis annularis).
Species collected in this study but not collected in 1987 include:
longnose gar (Lepisosteus osseus), alligator gar (L. spatula),
golden shiner (Notemigonus chrysoleucas), river carpsucker
(Carpiodes carpio), black bullhead (Ameiurus melas), and flathead
catfish (Pylodictus olivaris).
In 1997, fish samples were collected from the North Bosque River
by field personnel from the TNRCC assisted by the BRA and TIAER.
Four sites from the North Bosque River watershed were common to
both the TNRCC effort and this study. The 1997 study collected fish
from three sites not visited by TIAER while TIAER personnel sampled
two sites not visited by the TNRCC. Twenty-six total species were
collected from all sites sampled in 1997, while only 20 were
collected from the North Bosque River in this study. Species not
collected in this study but identified in the 1997 effort included:
spotted gar (Lepisosteus oculatus), gizzard shad (Dorosoma
cepedianum), European carp (Cyprinus carpio), blue catfish
(Ictalurus furcatus), spotted bass (Micropterus punctulatus),
smallmouth bass (M. dolomieui), redear sunfish (Lepomis microphus),
white crappie (Pomoxis annularis) and freshwater drum (Aplodinotus
grunniens). Species collected in 1998 but not identified in 1997
included: longnose gar (L. osseus), alligator gar (L. spatula),
fathead minnow (Pimephales promelas) and black bullhead (Ameiurus
melis).
Neils Creek was sampled by the TNRCC in 1989 as part of the
Texas Aquatic Ecoregion Project: An Assessment of Least Disturbed
Streams (TWC, 1992). Fifteen species were collected from this
location in 1989 and compared with 13 collected in this study.
Species collected in 1989 but not collected in 1998 included:
blackstrip topminnow (Fundulus notatus), mosquitofish (Gambusia
affinis) and Redear sunfish (Lepomis microlophus). Species
collected in 1998 but not identified in 1989 included: fathead
minnow (Pimephales promelas), mimic shiner (Notropis volucellus)
and flathead catfish (Pylodictis olivaris). TIAER personnel
observed, but did not collect, grey redhorse (Moxostoma congestum)
and river carpsucker (Carpiodes carpio). Additionally, TNRCC
reported an unidentified Lepomis hybrid and two species of
Micropterus (M. salmoides and M. punctulatus) which most likely are
both represented in the taxonomic category Micropterus sp. reported
by TIAER.
Though each agency made thorough efforts in sampling, some
differences in sampling methods were employed. The 1953 and 1987
efforts used seining only. The 1989, 1997 and 1998 efforts combined
seining and backpack electroshock. The 1997 and 1998 efforts also
utilized a gill net at specific locations where pool depth and
length allowed the net to be deployed. These differences may have
been responsible for some differences in species collected at
similar locations. For comparability, IBI scores were calculated
for the BRA study and recalculated for the 1987 TPW study based on
adjusted tolerance values developed by Linam and Kleinsasser
(unpublished draft, 1998). Additionally, BRA species diversity
values calculated using natural log, were recalculated using log2
for consistency with TPWD and TIAER.
bo020
No intolerant or darter species were collected, among the seven
fish species identified at this site (Table 8). The species
diversity value for this site was compared to
in 1997 (BRA, 1998), both in the range considered to indicate
moderate pollution ( ; Wilhm and Dorris, 1968). The index of
similarity (Table 6) indicated the fish community from this site
was most like bo070 and least like bo100.
H 2.01 2log( )=H 2.00=H 1 3–=
31
-
Fisheries Survey of the Bosque River Watershed Above Lake
Waco
The IBI integrity value of 40 (Table 7) indicated a rating of
fair compared to the poor to fair rating score (38) developed from
the 1997 BRA data (1998). A reason for the difference in these
score may have been a result of sampling differences. In 1997, the
backpack electroshock equipment malfunctioned, so only seine data
were presented in the BRA data. Low species richness, an absence of
darter and intolerant species, low numbers of cyprinid species and
an extremely high percentage of tolerant species resulted in a less
than excellent IBI rating. Approximately one-third of the community
were piscivors; however, this category was dominated (94 percent)
by a single species (Lepomis cyanellus).
bo040
No intolerant or darter species were collected among the nine
species identified at this site (Table 8). The species diversity
value for this site was , compared to reported by Linam and
Kleinsasser (1987) and reported from 1997 (BRA, 1998). All were in
the range considered to indicate moderate pollution ( ; Wilhm and
Dorris, 1968). The index of similarity (Table 6) indicated this
site was most like bo020 and least like hc060 and bo100.
The IBI value of 40 (Table 7) indicated a rating of fair. Though
the IBI yielded a slightly lower value than the score of 42
reported by both TPWD (Linam and Kleinsasser, 1987) and BRA,
(1998), the fair rating was consistent with each previous study.
Absence of darter and intolerant species, a low number of cyprinids
and invertebrate feeders, a high percentage of tolerant species and
low numbers of individuals resulted in a less than excellent IBI
rating for this study. These qualities were similar to those
expressed by Linam and Kleinsasser (1987).
bo070
No intolerant or darter species were identified among the 11
fish species collected at this site (Table 8). The species
diversity value for this site was , compared to recalculated from
the 1997 BRA study (BRA, 1998). For both studies, calculated
diversity index values indicated moderate pollution ( ; Wilhm and
Dorris, 1968). The index of similarity (Table 6) indicated this
site was most like gc100 and least like hc060.
The IBI value of 40 (Table 7) indicated a rating of fair. This
was lower than the value (42) developed from data collected in
November 1997 (1998). Low species richness; absence of darters and
intolerant species; a large percentage of tolerant species; and a
low percentage of piscivors resulted in a less than excellent IBI
rating. The difference between the BRA IBI and the one presented
here can be attributed to the presence of darter species, increased
species richness and more cyprinid species collected in November
1997.
bo100
Of the 15 fish species collected at this site (Table 8), one
darter species was identified, but no intolerant species were
collected at this site. Species diversity for this site was , the
second lowest value of all sites visited. Most likely, this value
was negatively impacted by an extremely large number of red shiners
(C. lutrensis). The diversity index value calculated for this site
is indicative of moderate pollution ( ; Wilhm and Dorris, 1968).
The index of similarity (Table 6) indicate bo100 is most like gc100
and least like bo020.
The IBI value of 46 (Table 7) calculated for this site was
higher than the previous sites discussed, resulting in a rating of
fair to good. Low number of darter species; absence of
H 2.672
log( )= H 1.25=H 2.00=
H 1 3–=
H 1.20 2log( )= H 2.34=
H 1 3–=
H 1.70 2log( )=
H 1 3–=
32
-
Fisheries Survey of the Bosque River Watershed Above Lake
Waco
intolerant species; high percentage of tolerant species; and a
very low percentage of piscivors resulted in a less than excellent
IBI rating.
gc100
No darter or intolerant species were collected among the 11
species identified at this site (Table 8). The species diversity
value for this site was , the highest of all sites monitored, and
higher than the diversity values calculated from data reported by
the BRA ( ; 1998). Though near the upper range of values considered
indicative of moderate pollution ( ; Wilhm and Dorris, 1968), the
diversity indices from both studies indicate moderate pollution.
The index of similarity (Table 6) indicates this site is most like
bo070 and least like mb060.
The IBI value of 42 (Table 7) calculated for this site from
March data was two points lower than November, 1997 data (BRA,
1998); however, both values are within the range considered fair.
The absence of darter and intolerant species, a high percentage of
tolerant species, a low number of total individuals and a low
number of cyprinid species resulted in a less than excellent IBI
rating. The difference between the IBI developed from the BRA data
and data collected by TIAER was a larger number of individuals
collected in 1997. Lower numbers of cyprinid species collected in
1998 than in 1997 was offset by a higher percentage of piscivors
collected in 1998 than in 1997. The difference in piscivors may
have been a result of deploying a gill net in 1998 that was not
done in 1997, resulting in the collection of several piscivorous
longnose gar (Lepisosteus osseus).
nc060
Thirteen fish species were collected at this site (Table 8),
including one darter species. No intolerant species were collected
at Neils Creek. Species diversity for this site was
, indicating moderate pollution ( ; Wilhm and Dorris, 1968). The
index of similarity (Table 6) revealed nc060 is most like bo070 and
gc100 and least like bo040.
The IBI value of 50 (Table 7) calculated for this site was the
second highest of all sites sampled, resulting in a rating of good.
Low numbers of darter species, no intolerant species and a low
percentage of invertebrate feeders resulted in a less than
excellent IBI rating. The higher rating than previously discussed
sites was a result of a reduced percentage of tolerant species.
Data from the 1987 sampling effort (TWC, 1992) yielded an IBI of
46, which results in a rating of fair to good. Differences that
resulted in a lower IBI score in 1987 were fewer numbers of
cyprinids, a lower percentage of piscivors and the presence of
hybrid species.
hc060
Eleven species were collected at this location (Table 8),
including one darter species. No intolerant species were collected
at this site. Species diversity for this site was , third highest
of all sites sampled but still in the range that indicates moderate
pollution (Wilhm and Dorris, 1968). The index of similarity (Table
6) indicated this site was most like nc060 and least like
bo040.
The IBI value of 40 (Table 7) calculated for this site resulted
in a rating of fair. Low species richness, few darter and cyprinid
species, no intolerant species, an elevated percentage of tolerant
species, a low percentage of invertebrate feeders and a low number
of total individuals resulted in a less than excellent IBI rating.
No other samples from this location were found for comparison.
H 2.99 2log( )=
H 1.77=H 1 3–=
H 2.70 2log( )= H 1 3–=
H 2.79 2log( )=
33
-
Fisheries Survey of the Bosque River Watershed Above Lake
Waco
mb060
Nine fish species were collected at this site (Table 8),
including one darter species. No intolerant species were collected
at this location. Species diversity for this site was
, compared to in 1987 (Linam and Kleinsasser, 1987). Although
for this site was below the average for all sites, it was in the
range indicating moderate pollution (Wilhm and Dorris, 1968).
Though community composition between the two surveys was similar,
the very low diversity index from 1987 most likely resulted from an
extremely high percentage (88 percent) of blacktail shiners
(Cyprinella venusta) which negatively impacted the index. The index
of similarity (Table 6) indicated this site was most similar to
nc060 and least like bo020.
The IBI score for this site of 40 (Table 7) resulted in a rating
of fair. Low numbers of species and darters, no intolerant species,
high percentages of tolerant species and omnivores, and a low
percentage of invertebrate feeders resulted in a less than
excellent IBI rating. The IBI score for the 1987 study was 46,
giving this site a rating of fair to good (Linam and Kleinsasser,
1987). The major differences between the two scores were: lower
percentages of tolerant and omnivore species; and a higher
percentage of invertebrate feeders.
H 2.07 2log( )= H 0.86= H
34
-
Fisheries Survey of the Bosque River Watershed Above Lake
Waco
Tab
le 9
Ind
ex o
f bio
tic
inte
grit
y su
mm
ary
tabl
e of
fish
es c
olle
cted
in th
e B
osqu
e R
iver
w
ater
shed
(Spr
ing1
999)
bo02
0bo
040
bo07
0gc
100
mb0
60hc
060
nc06
0bo
100
sb06
0
Spec
ies R
ichne
ss a
nd Co
mpo
sitio
n/M
etric
Sco
re
Tota
l num
ber
of s
peci
es7
39
311
311
510
311
313
515
520
5D
arte
rs0
10
10
10
11
31
31
31
32
5Su
nfis
h3
53
53
53
53
53
53
53
53
5C
ypri
nids
23
23
33
33
35
23
55
55
65
Into
lera
nts
01
01
01
01
01
01
01
11
25
Tole
rant
s86
%1
61%
180
%1
62%
179
%1
35%
117
%3
11
49%
1Tr
ophi
c Com
posit
ion
/Met
ric S
core
Om
nivo
res
1%5
7%5
0.4%
54%
570
%1
20%
39%
515
%5
12%
5In
vert
ebra
te fe
eder
s66
%3
48%
395
%5
72%
314
%1
64%
377
%3
83%
553
%3
Pisc
ivor
s33
%5
23%
50.
2%1
15%
515
%5
16%
514
%5
1%1
2%3
Fish
Abu
ndan
ce a
nd C
ondi
tion
/ Met
ric S
core
Tota
l num
ber
of in
divi
dua
ls16
13
114
312
405
141
334
45
193
320
35
1971
566
45
Hyb
rids
0%5
0%5
0%5
0%5
0%5
0%5
0%5
0%5
0%5
Dis
ease
d0%
50%
50%
50%
50%
50%
50%
50%
51.
40%
5To
tal m
etri
c sc
ore
4040
4042
4040
5046
52R
atin
gfa
irfa
irfa
irfa
irfa
irfa
irgo
odfa
ir to
goo
dgo
od
35
-
Fisheries Survey of the Bosque River Watershed Above Lake
Waco
sb060
Twenty fish species, the highest species richness of all sites
sampled, were collected at this site (Table 8), including two
darter species and two intolerant species. Species diversity for
this site was , compared to 2.94 in 1987 (Linam and Kleinsasser,
1987). This value, though second highest of all sites sampled, was
still in the range indicating moderate pollution (Wilhm and Dorris,
1968). The index of similarity (Table 6) indicated the fish
community was most like nc060 and least like bo020 and gc100.
The IBI score of 52 (Table 7) calculated for this site resulted
in a rating of good to excellent. Sb060 yielded the highest IBI of
all sites monitored by TIAER, and was two points higher than the
value calculated by Linam and Kleinsasser (1987). A large
percentage of tolerant species, moderate percentage of invertebrate
feeders and moderate percentage of piscivors prevented this site
from achieving a rating of excellent.
DiscussionData collected from the Bosque River drainage suggests
that the habitat necessary to support a diversity of aquatic life
is adequate but not necessarily optimal. The habitat quality index
(HQI) scores for eight sites were in the intermediate range; the
next to lowest of the four scoring categories. Only mb060
scored