fisheries survey of the bosque river watershed above lake wacotiaer.tarleton.edu/pdf/pr0005.pdf ·...

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

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.

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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.

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H

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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

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6

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

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8

Figures

Figure 1 Sites selected for the survey . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13Figure 2 Habitat Quality Index (HQI) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17Figure 3 Stream Physical Characteristics Worksheet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

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10

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).

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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.

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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.

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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.

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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

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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

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Figu

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17


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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


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


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


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


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


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


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


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


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


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 (


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


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


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


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


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


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


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


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


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

fisheries survey of the bosque river watershed above lake wacotiaer.tarleton.edu/pdf/pr0005.pdf ·...

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