Shields River habitat and aquatic invertebrate assessment, September 2000

MONTANA STATE LIBRARY

3 0864 0015 5614 4

SHIELDS RIVER

HABITAT AND AQUATIC INVERTEBRATE ASSESSMENT

September, 2000

STATE DOCUMENTS COLLECTION

.UN 1 Q 2001

MONTANA STATE LIBRARY

1515 E. 6th AVE.
HELENA. MONTANA 59620

Report prepared for

The Montana Department of Environmental Quality

Helena, Montana

Prepared by

Wease Bollman

Rhithron Biological Associates

Missoula, Montana

April, 2001

fi-'R 0 2

DATE

DUE

_2aui-^-

-1 LB /, ^

i

i

INTRODUCTION

Aquatic invertebrates are aptly applied to bioassessment since they are known to
be important indicators of stream ecosystem health (Hynes 1970). Long lives, complex
life cycles and limited mobility mean that there is ample time for the benthic community
to respond to cumulative effects of environmental perturbations

This report summarizes data collected in September 2000 from two sites on the
Shields River, Montana A multimetric approach to bioassessment was applied to the
data: this approach uses attributes of the benthic invertebrate assemblage in an integrated
way to measure biotic health. A stream with good biotic health has been described as
. . .a balanced, integrated, adaptive system having the full range of elements and processes
that are expected in the region's natural environment. . ." (Karr and Chu 1999).

The additive muhimetric approach designed by Plafkin et al. (1989) and adapted
for use in the State of Montana is ". . . an artay of measures or metrics that individually
provide information on diverse biological attributes, and when integrated, provide an
overall indication of biological condition." (Barbour et al. 1995). Community attributes
that can contribute meaningfully to interpretation of benthic data include assemblage
structure, sensitivity of community members to stress or pollution, and functional traits.
Each metric component contributes an independent measure of the biotic integrity of a
stream site, combining the components into a total score reduces variance and increases
precision of the assessment (Fore et al. 1994) Effectiveness of the integrated metrics
depends on the applicability of the underlying model, which rests on a foundation of
three essential elements (BoUman 1998). The first of these is an appropriate stratification
or classification of stream sites, typically, by ecoregion. Second, metrics must be selected
based upon their ability to accurately express biological condition Third, an adequate
assessment of habitat conditions at each site to be studied is advantageous to the
interpretation of metric outcomes.

Implicit in the multimetric method and its associated habitat assessment is an
assumption of correlative relationships between habitat parameters and the biotic metrics,
in the absence of water quality impairment These relationships may vary regionally,
requiring an examination of habitat assessment elements and biotic metrics and a test of
the presumed relationship between them This writer (1998) has recently studied the
assemblages of the Montana Valley and Foothill Prairies ecoregion, and has
recommended a battery of metrics specific to that ecoregion, which has been shown to be
sensitive to impairment, related to habitat assessment parameters and consistent over
replicated samples.

Habitat assessment enhances the interpretation of biological data (Barbour and
Stribling 1991), because there is generally a direct response of the biological community
to habitat degradation in the absence of water quality impairment. If biotic health appears
more damaged than the habitat quality would predict, water pollution by metals, other
toxicants, high water temperatures, or high levels of organic and/or nutrient pollution
might be suspected. On the other hand, an "artificial" elevation of biotic condition in the
presence of habitat degradation may be due to the paradoxical effect of mild nutrient or
organic enrichment in an oligotrophic setting.

METHODS

Aquatic invertebrates were sampled by Pat Newby of the Montana Department of
Environmental Quality (MT DEQ). Two sites on Shields River were sampled; Table 1
gives site locations. Both sites lie within the Montana VaUeys and Foothill Prairies
(MVFP) ecoregion.The sampling method employed is described in the MT DEQ
Standard Operating Procedures for Macroinvertebrate Sampling (Bukantis 1998). In
addition, habitat quality was evaluated by scoring various instream, streambank and
riparian zone parameters using a DEQ-modified version of the U.S. EPA's Rapid
Bioassessment Protocols. Aquatic invertebrate samples and associated habitat assessment
data were delivered to Rhithron Biological Associates, Missoula, Montana, for laboratory
and data analyses.

Table 1. Sampling locations on Sliields River. August 2000.

Sampling
station

McCloud
Johnstone

Latitude Longitude

46° 09' 56" 110° 34' 05'"
45° 57' 21" 110° 37' 57"

In the laboratory, the Montana DEQ-recommended sorting method was used to
obtain subsamples of at least 300 organisms from each sample. Organisms were
identified to the lowest possible taxonomic levels consistent with Montana DEQ
protocols.

To assess invertebrate communities in this study, a multimetric index developed
in previous work for streams of western Montana (Bollman 1998) was used. Multimetric
indices result in a single numeric score, which integrates the values of several individual
indicators of biologic health. Each metric used in this index was tested for its response or
sensitivity to varying degrees of human influence. Correlations have been demonstrated
between the metrics and various symptoms of human-caused impairment as expressed in
water quality parameters or instream, streambank and stream reach morphologic features.
Metrics were screened to minimize variability over natural environmental gradients, such
as site elevation or sampling season, which might confound interpretation of results. The
multimetric index used in this report incorporates multiple attributes of the sampled
assemblage into an integrated score that accurately describes the benthic community of
each site in terms of its biologic integrity. In addition to the metrics comprising the index,
other metrics, which have been shown to be applicable to biomonitoring in other regions
(Kleindl 1995, Patterson 1996, Rossano 1995), were used for descriptive interpretation of
Shields River results. These metrics include the number of "dinger" taxa, long-lived taxa
richness, the percent of predatory organisms, and others. They are not included in the
integrated bioassessment score, however, since their performance in the ecoregions of
Montana is unknown. However, the relationship of these metrics to habitat conditions is
intuitive and reasonable.

The six metrics comprising the bioassessment index used in this study were
selected because both individually and as an integrated metric battery, they are robust at
distinguishing impaired sites from relatively unimpaired sites (Bollman 1998). In
addition, they are relevant to the kinds of impacts that are present in the Shields River
drainage, and they have been demonstrated to be more variable with anthropogenic

impairment than with natural environmental gradients Each of the six metrics developed
and tested for western Montana ecoregions is described below.

1. Ephemeroptera (mayfly) taxa richness. The number of mayfly taxa declines as
water quality diminishes Impairments to water quality which have been
demonstrated to adversely affect the ability of mayflies to flourish include elevated
water temperatures, heavy metal contamination, increased turbidity, low or high pH,
elevated specific conductance and toxic chemicals. Few mayfly species are able to
tolerate certain disturbances to instream habitat, such as excessive sediment
deposition

2. Plecoptera (stonefly) taxa richness. Stoneflies are particularly susceptible to
impairments that affect a stream on a larger or reach-level scale, such as loss of
riparian canopy, streambank instability, and alteration of morphological features such
as pool fi-equency and fijnction, riffle development and sinuosity. Just as all benthic
organisms, they are also susceptible to smaller scale habitat loss, such as by sediment
deposition, loss of interstitial spaces between substrate particles, or unstable substrate.

3. Trichoptera (caddisfly) taxa richness. Caddisfly taxa richness has been shown to
decline when sediment deposition affects their habitat. In addition, the presence of
certain case-building caddisflies can indicate good retention of woody debris and lack
of scouring flow conditions

4. Number of sensitive taxa. Sensitive taxa are generally the first to disappear as
anthropogenic disturbances increase The list of sensitive taxa used here includes
organisms sensitive to a wide range of disturbances, including warmer water
temperatures, organic or nutrient pollution, toxic pollution, sediment deposition,
substrate instability and others. Unimpaired streams of western Montana typically
support at least four sensitive taxa (Bollman 1998).

5. Percent filter feeders. Filter-feeding organisms are a diverse group, they capture
small particles of organic matter, or organically enriched sediment material, ffom the
water column by means of a variety of adaptations, such as silken nets or hairy
appendages. In forested montane streams, filterers are expected to occur in
insignificant numbers Their abundance increases when canopy cover is lost and
when water temperatures increase and the accompanying growth of filamentous algae
occurs. Some fihering organisms, specifically the Arctopsychid caddisflies
(Arctopsyche spp. and Parapsyche spp.) build silken nets with large mesh sizes that
capture small organisms such as chironomids and eariy-instar mayflies. Hence, they
are considered predators and in this study their abundance does not contribute to the
percent filter feeders metric.

6. Percent tolerant taxa. Tolerant taxa are ubiquitous in stream sites, but when
disturbance increases, their abundance increases proportionately. The list of taxa used
here includes organisms tolerant of a wide range of disturbances, including warmer
water temperatures, organic or nutrient pollution, toxic pollution, sediment
deposition, substrate instability and others.

Scoring criteria for each of the six metrics are presented in Table 2. Metrics differ in
their possible value ranges and in the direction the values move as biological conditions
change. For example, Ephemeroptera richness values may range fi-om zero to ten taxa or

higher. Larger values generally indicate favorable biotic conditions. On the other hand,
the percent filterers metric may range from 0% to 100%, in this case, larger values are
negative indicators of biotic health. To facilitate scoring, therefore, metric values are
transformed onto a single scale. The range of each metric has been divided into four parts
and assigned a point score between zero and three. A score of three indicates a metric
value similar to one characteristic of a non-impaired condition. A score of zero indicates
strong deviation from non-impaired condition and suggests severe degradation of biotic
health. Scores for each metric were summed to give an overall score, the total
bioassessment score, for each site in each sampling event. These scores were expressed
as the percent of the maximum possible score, which is 18 for this metric battery.

Table 2. Metrics and scoring criteria for bioassessment of streams of western Montana

ecoregions

(Boilman 1998).

Score

Metric

3

2

1

0

Ephemeroptera taxa richness

>5

5-4

3-

2

<2

Plecoptera taxa richness

>3

3 -2

1

0

Trichoptera taxa richness

>4

4-3

2

<2

Sensitive taxa richness

>3

3-2

1

0

Percent filterers

0-5

5.01 - 10

10.01

-25

>25

Percent tolerant taxa

0-5

5.01 - 10

10.01

-35

>35

The total bioassessment score for each site was expressed in terms of use-support.
Criteria for use-support designations were developed by MT DEQ and are presented in
Table 3a For descriptive purposes, scores were also translated into impairment
classifications according to criteria outlined in Table 3b.

Table 3a. Criteria for the assignment of use-support classifications / standards violation thresholds (from
Bukantis, 1997)

% Comparability to reference

Use support

>75

25-75

<25

Full support—standards not violated

Partial support-moderate impairment-standards

violated

Non-support-severe impairment-standards violated

Table 3b. Criteria for the assignment of impairment classifications (from Plafldn et al. 1989).

% Comparability to reference

Classification

>83

54-79
21-50
<17

nonimpaired
slightly impaired
moderately impaired
severely impaired

In this report, certain other metrics were used, when appropriate, as descriptors of
the benthic community response to habitat or water quality but were not incorporated into
the bioassessment metric battery, either because they have not yet been tested for
reliability in streams of western Montana, or because results of such testing did not show
them to be robust at distinguishing impairment, or because they did not meet other
requirements for inclusion in the metric battery. These metrics and their use in predicting
the causes of impairment or in describing its effects on the biotic community are
described below.

• The modified biotic index. This metric is an adaptation of the Hilsenhoff Biotic
Index (HBI, Hilsenhoff 1987), which was originally designed to indicate organic
enrichment of waters. Values of this metric are lowest in least impacted
conditions. Taxa tolerant to saprobic conditions are also generally tolerant of
warm water, fine sediment and heavy filamentous algae growth (BoUman,
impublished data). Loss of canopy cover is often a contributor to higher biotic
index values. The taxa values used in this report are modified to reflect habitat
and water quality conditions in Montana (Bukantis 1998). Ordination studies of
the benthic fauna of Montana's foothill prairie streams showed that there is a
correlation between modified biotic index values and water temperature, substrate
embeddedness, and fine sediment (Bollman 1998). In a study of reference
streams, the average value of the modified biotic index in least -impaired streams
of western Montana was 2.5 (Wisseman 1992).

• Taxa richness. This metric is a simple count of the number of unique taxa present
in a sample. Average taxa richness in samples from reference streams in western
Montana was 28 (Wisseman 1992). Taxa richness is an expression of biodiversity,
and generally decreases with degraded habitat or diminished water quality.
However, taxa richness may show a paradoxical increase when mild nutrient
enrichment occurs in previously oUgotrophic waters, so this metric must be
interpreted with caution.

• Percent shredders. Shredding organisms consume large particles of detritus such
as leaves, needles and wood. Foothill and prairie streams with healthy riparian
vegetation and sufficient instream structure to retain detritus will have large
numbers of shredders Often, this feeding group dominates the fauna of headwater
streams. The abundance of shredders generally increases in the fall, when leaf and
blade input to streams maximizes. In another study, average shredder contribution
in western Montana reference streams was 8% (Wisseman 1 992).

• Percent predators. Aquatic invertebrate predators depend on a reliable source of
invertebrate prey, and their abundance provides a measure of the trophic
complexity supported by a site. Less-disturbed sites have more plentiful habitat
niches to support diverse prey species, which in turn support abundant predator
species.

• Number of "dinger" taxa. So-called "dinger" taxa have physical adaptations that
allow them to cling to smooth substrates in rapidly flowing water. Aquatic
invertebrate "dingers" are sensitive to fine sediments that fill interstices between
substrate particles and eliminate habitat complexity. Animals that occupy the
hyporheic zones are included in this group of taxa. Expected "dinger" taxa

richness in unimpaired streams of western Montana is at least 14 (Bellman,
unpublished data).

Number of long-lived taxa. Long-lived or semivoltine taxa require more than a
year to completely develop, and their numbers decline when habitat and/or water
quality conditions are unstable. They may completely disappear if channels are
dewatered or if there are periodic water temperature elevations or other
interruptions to their Life cycles. Western Montana streams with stable habitat
conditions are expected to support six or more long-lived taxa (Bollman,
unpublished data).

i

RESULTS

Habitat assessment

Figure 1 compares habitat assessment results for the two sites studied. Breakdown
of total scores into the nine evaluated components is presented in Table 1.

Figure L Total habitat assessment scores, expressed as percent of maximum, for two sites on Siiields
River, August, 2000.

McCloud station

Johnstone station

Habitat assessments indicate that conditions contrasted sharply between McCloud
station and Johnstone station. Overall assessment at McCloud station suggested sub-
optimal conditions, whereas Johnstone station was judged to have marginal habitat. At
McCloud station, all but one of the instream indicators were scored optimally; the
exception was sediment deposition, since some point bar formation was noted. In
addition, flow status was judged sub-optimal, as were all of the streambank and riparian
indicators.

In contrast, degradation of instream habitats was indicated by the assessment
conducted at Johnstone station. Substrate embeddedness was noted, and sediment
deposition was judged to be heavy. The investigator detected marginal flow status at this
location. Streambank stability and vegetation were given poor scores, and the riparian
zone was noted to be minimally intact.

4

Table 4. Stream and riparian habitat assessment: Shields River, August 2000.

Maximum

possible

score

Location:

McCloud
station

Johnstone
station

Parameter

10

Riffle development

9

9

10

Benthic substrate

9

6

20

Embeddedness

16

6

20

Channel alteration

20

18

20

Sediment deposition

15

4

20

Channel flow status

14

7

10/10

Bank stability (left/right)

12

4

10/ 10

Bank vegetation protection
(left/right)

7/7

2/2

10/10

Riparian vegetation zone width
(left/right)

7/7

2/2

160

TOTAL SCORE

123

62

PERCENT OF MAXIMUM:

77

39

CONDITION'

SUB-
OPTIMAL

MARGINAL

'Optimal >8I%, Sub-Optimal 75-56%, Marginal 49-29%, Poor <23%. (Plafkin et al. 1989.)

Bioassessment

Aquatic invertebrate taxa lists, metric results and other information for each
sample are given in the Appendix. Figure 2 compares the total bioassessment scores
calculated for invertebrate communities collected at each of the two sites. Breakdown of
scores for each metric calculated from Shields River invertebrate samples is presented in
Table 5.

Figure 2. Total bioassessment scores, expressed as percent of maximum, for two sites on Shields River,
August 2000.

McCloud station

Johnstone station

The benthic assemblage sampled at McCloud station scored maximal values for
all but one of the bioassessment metrics, resulting in a total score indicating excellent
biotic health. Full support of designated uses was indicated. The percentage of filter-
feeding organisms was higher than expected for an unimpaired site. At Johnstone station,
on the other hand, mayfly richness, stonefly richness and caddisfly richness were all
lower than expected in undisturbed conditions, and no sensitive taxa were collected. In
addition, a large proportion of sampled organisms were tolerant, and a large proportion
were filter-feeders The total bioassessment score calculated for the assemblage sampled
at this site indicated moderate impairment of biotic health and partial support of
designated uses.

Table 5. Metric values and bioassessments for Shields River, August 2000.

Sites

McCloud

Johnstone

station

station

Metric

Ephemeroptera richness

8

3

Plecoptera richness

8

1

Trichoptera richness

9

4

Sensitive taxa richness

5

0

Percent tolerant taxa

3

26

Percent filter-feeders

9

29

Metric scores

Ephemeroptera richness

3

1

Plecoptera richness

3

1

Trichoptera richness

3

2

Sensitive taxa richness

3

0

Percent tolerant taxa

3

1

Percent filter-feeders

2

0

Total score (maximiun = 18)

17

5

Percent of maximum

94

28

Use support*

FULL

PARTIAL

Impairment classification'

NON

MOD

1. Classifications; (NON) non-impaired, (SLI) sUghUy impaired, (MOD) moderately impaired, (SEV)

severely impaired. See Table 3b.

*Use support designations; See Table 3a.

Aquatic invertebrate communities

Shields River at McCloud station supported a benthic assemblage typical of a
weatem Montana stream with little disturbance. The community was diverse (37 taxa
were present in the sample) and most functional components were adequately
represented. Nine percent of the sampled assemblage were fiher-feeders, a proportion

elevated slightly above that expected Most of the filter-feeding organisms were the
caddisfly Hydropsyche sp. This finding suggests that suspended fine organic particulates
were plentifijl in this reach, perhaps compromising water quality to a slight degree. It also
correlates with the finding of slight streambank instabiUty, sub-optimal riparian zone
integrity, and light deposition of fine sediments noted in the habitat assessment. The
overall affect of these conditions on biotic health, however, appears to be very slight.
Eight mayfly taxa and a low biotic index value (2 36) suggest that water quality
perturbations do not substantially impair biotic health in this reach Excellent large-scale
habitat is indicated by the high number of stonefly taxa, among them were the sensitive
shredder Zapada columbiatKi and the perlid Doroneuria sp., which is also sensitive to
many types of habitat disturbance Long-lived taxa, including three different species of
perlid stoneflies and the caddisfly Arctopsyche grandis were abundant, indicating
adequate year-round streamflow and no periodic disruptive events. The presence of 9
caddisfly taxa and 18 "dinger" taxa suggests that the slight sediment deposition noted by
the field investigator does not compromise biotic health to any great extent. Predator taxa
were abundant and diverse, ten taxa comprised 16% of the sampled assemblage. This
suggests good instream habitat. Sixteen percent of the organisms sampled were
shredders, indicating good riparian inputs of large organic material, and stream
morphology and flow conditions adequate for retention of such material

At Johnstone station, on the other hand, only 3 mayfly taxa were represented in
the sample, and the biotic index value (4.89) was considerably higher than expected. In
addition, 33% of the assemblage were midges. These findings suggest that water quality
impairs biotic health in this reach of Shields River Abundant filter-feeders (29°/o of the
assemblage) suggest that fine suspended organic material was abundant here, and may be
an indication of poor streambank stability and associated erosion, heavy sediment
deposition, and embeddedness of benthic substrates noted in the habitat assessment. No
sensitive taxa were present in the sample Only two predator taxa (1% of the assemblage),
most of them the tolerant svn^t^y Atherix sp , were collected, suggesting monotonous
substrates and poor instream habitat quality. Further, 4 caddisfly taxa, dominated by the
sediment-tolerant Hydropsyche sp , and 10 "dinger" taxa were present in the sample,
indicating that sediment deposition limited the diversity of benthic invertebrates here.
Only 20 unique ta.xa were collected A single shredder taxa was present, indicating very
limited riparian contribufions of large organic material.

CONCLUSIONS

• With the exception of a slightly elevated filter- feeder component to the
assemblage, the benthic invertebrates at the McCloud station indicate essentially
unimpaired biotic health Increased filter-feeders may indicate excessive
suspended fine organic particulates, which in this reach of Shields River may be a
consequence of some degree of streambank instability and associated erosion.

• Both water quality perturbations and habitat degradation appear to impair biotic
health at the Johnstone station. Impairment was classified as "moderate", but the
score was very low Metric performance and taxonomic composition of the
assemblage suggested that water quality was impaired by nutrient and/or organic
enrichment. Habitat degradation appears to have resulted in heavy fine sediment
deposition with the resultant loss of instream habitat

• The relationship between habitat assessment scores and bioassessment scores
suggests that neither water quality nor habitat degradation limited biotic health at
McCloud station. However, both habitat degradation, and, to a lesser extent,
diminished water quality combined to impair integrity at Johnstone station. Figure
3 illustrates these relationships. The point representing McCloud station lies high
in the upper right quadrant of the graph, where its high habitat assessment score is
coupled with a high bioassessment score. In contrast, the point representing
Johnstone station lies slightly below a line describing the expected relationship
between habitat and biotic health when water quality is unimpaired.

Figure 3. Total bioassessment scores plotted against habitat assessment scores for two sites on Shields
River, August 2000. The red line describes the hypothetical relationship expected when water quality is
good and biotic health is determined predominantly by habitat quality (Barbour and Stribling 1991).

100
90
80
70
60
50
40
30
20
10

TT

10

20

— I —
30

i

40 50 60

Habitat assessment score

70

80

90

-McCloud station O Johnstone station

LITERATURE CITED

Barbour. M T.. J B Stribling and JR. Karr. 1995 Multimetric approach for establishing biocriteria and
measuring biological condition Pages 63-79 in W.S. Davis and T.P Simon (editors) Biological Assessment
and Criteria: Tools for Water Resource Planning and Decision Making. Lewis Publishers. Boca Raton.

Barbour. M.T. and J.B. Stribling 1991 Use of habitat assessment in evaluating the biological integrit>' of
stream communities In: Biological Criteria: Research and Regulation Proceedings of a S>Tnposium. 12-
13 December 1990, Arlington, Virginia. EPA-440-5-9 1-005. U.S. Environmental Protection Agency,
Washington. DC.

BoUman. VV 1998. lmpro\ing Stream Bioassessment Methods for the Montana Valleys and Foothill
Prairies Ecoregion Unpublished Master's Thesis University of Montana. Missoula, Montana.

Bukantis, R. 1997. Rapid bioassessment macroinvertebrate protocols: Sampling and sample analysis
SOP'S Working draft, 1998. Montana Department of Environmental Quality. Planning Prevention and
Assistance Division. Helena, Montana.

Fore, L.S.. JR. Karr and L.L. Conquest. 1994. Statistical properties of an inde.x of biological integrity used
to evaluate water resources. Canadian Journal of Fisheries and Aquatic Sciences. 51: 1077-1087

Fore, L S.. JR. Karr and R.W Wisseman. 1996. Assessing invertebrate responses to human activities:
evaluating alternative approaches. Journal of the North American Benlhological Society 15(2): 2 12-23 1.

HilsenhofF, W.L. 1987. An improved biotic index of organic stream pollution. Great Lakes Entomologist.
20: 31-39.

Hynes. H B N. 1970 The Ecology of Running Haters. The University of Toronto Press. Toronto.

Kleindl, W.J 1995 A benthic index of biotic integrit\- for Puget Sound Lowland Streams, Washington,
USA. Unpublished Master's Thesis University of Washington, Seattle. Washington.

Omermk J.M. 1997. Level Ill-Level IV ecoregions of Montana. Unpublished First Draft. August, 1997.

Patterson, A.J. 1996. The effect of recreation on biotic integrity of small streams in Grand Teton National
Park. Unpublished Master's Thesis University of Washington, Seattle. Washington

Plafkin. J L . M T. Barbour, K.D. Porter, S K. Gross and R.M.Hughes 1989. Rapid Bioassessment
Protocols for Use in Streams and Rivers. Benthic Macroinvertebrates and Fish. EPA 440-4-89-001. OfBce
of Water Regulations and Standards, US. Environmental Protection Agency, Washington, DC.

Rossano, EM. 1995. Development of an inde.x of biological integrity for Japanese streams (IBI-J).
Unpublished Master's Thesis. University of Washington, Seattle, Washington.

Wisseman, R.W. 1992. Montana rapid bioassessment protocols. Benthic invertebrate studies, 1990.
Montana Reference Streams study. Report to the Montana Department of Environmental Quality. Water
Quality Bureau. Helena. Montana.

Barbour, M T. and J.B. Stribling. 1991. Use of habitat assessment in evaluating the biological integrit)' of
stream commumties. In: Biological Criteria: Research and Regulation. EPA-440-5-9 1-005. U. S.
Environmental Protection Agency, Office of Water, Washington, DC.

i

APPENDIX

Aquatic invertebrate taxonomic and metric data,
Shields River, August 2000.

Aquatic Macroinvertebrate Taionomic Data

Site NamerShields River
Site ID: Johnstone station
Taion

9/19/00

Approx. percent of sample used: 6
Quantity Percent

Amiocentrus aspilus
Brachycentrus occidentalis
Hydropsyche sp
Lepidostoma sp -sand case larvae

Cncotopus sp,

Eukieffenella Pseudomontana Gr.

Microtendipes sp

Orthocladms sp

Tvetenia sp

HBI

FFG

Physidae
Acari

32
3

9,76
0,91

8

5

CG
PA

Total Misc. Taxa

35

10.67

Ephemerellidae - early instar
Rhithrogena sp.
Triconthodes minutus

1
1

1

030
0,30
0,30

1
0
4

CG
SC
CG

Total Ephemeroptera

3

0.91

Skrwala sp-

I

0,30

2

PR

Total Plecoptera

1

0.30

14

4,27

3

CG

1

0.30

1

OM

95

28.96

4

CF

18

5.49

1

SH

Total Trichoptera

128

39.02

\iicroc\ltoepiis sp.
Optioservus sp.

Zaitze\'ia sp.

1

37

9

0.30
11.28

2.74

7
4
4

SC
SC
CG

Total Coleoptera

47

14.33

Athenx sp
Antocha sp,

3

1

0.91
0,30

4
3

PR
CG

Total Diptera

4

1.22

1

3.35

7

CG

5

1.52

8

OM

2

0.61

6

CG

»1

27.74

6

CG

1

030

5

CG

Total Chironomidae

110

33.54

Grand Total

328

100.00

Aquatic Macroinvertebrate Summary Data

9/19/00

Site Name: Shields River

Site ID: McCloud station

TOTAL ABUNDANCE
Ephemeroptera + Plecoplera +
Trichoptera (EPT) abundance

TOTAL NUMBER OF TAXA
Number EPT taxa

TAXONOMIC GROUP COMPOSITION

322

264

37
24

GROUP

Misc. Taxa

Odonata

Ephemeroptera

Plecoptera

Hemiptera

Megaloptera

Trichoptera

Lepidoptera

Coleoptera

Diptera

Chrionomidae

#TAXA ABUNDAN PERCENT

2

2

0.62

0

0

0.00

8

80

24.84

8

49

15.22

0

0

0.00

0

0

0.00

8

135

41.93

0

0

0.00

3

10

3.11

3

6

1.86

5

40

12.42

CONTRIBUTION OF DOMINANT TAXA

TAXON ABUNDANCE

Glossosoma sp.

Cinygmula sp.

Lepidostoma sp.-sand case larv.

Hydropsyche sp.

Orthocladius sp

SUBTOTAL 5 DOMINANTS

Zapada cinctipes

Rhithrogena sp

Hesperoperla pacifica

Arctopsyche grandis

Brachycentrus americanus

TOTAL DOMINANTS

SAPROBIC INDICES
HilsenhofFBiotic Index

CE :

PERCENT

41

12.73

38

11.80

28

8.70

27

8.39

23

7.14

157

48.76

22

6.83

16

4.97

14

4.35

12

3.73

10

3.11

231

71.74

2.36

RATIOS OF TAX GROUP ABUNDANCES
EPT/Chironormdae

6.60

FUNCTIONAL FEEDING GROUP (FFG) COMPOSITION

GROUP

Predator

Parasite

Collector-gatherer

Collector-filterer

Macrophyte-herbivore

Piercer-herbivore

Scraper

Shredder

Xylophage

Omnivore

Unknown

RATIOS OF FFG ABUNDANCES
Scraper/Collector-filterer
Scraper/( Scraper + C filterer)
Shredder/Total organisms

#TAXA ABUNDAN PERCENT

10

52

16.15

0

0

0.00

15

63

19.57

2

29

9.01

1

5

1.55

1

9

2.80

4

103

31.99

3

51

15.84

0

0

0.00

1

10

3.11

0

S

0

0.00

3.55
0.78
0.05

DIVERSrrY MEASURES
Shannon H (loge)
Shannon H (Iog2)
Evenness
Simpson D

2.68
3.87
0.74
0.06

COMMUNITY VOLTINISM ANALYSIS
TYPE ABUNDANCE PERCENT

Multivoltme 40 12.42

Univoltine 224 69.57

Semivoltine 58 18.01

Tolerant

Intolerant

dinger

#TAXA ABUNDANCE PERCENT
2 10 311

6 24 7.45

18 198 61.49

Aquatic Macroinvertebrate TaxoDomic Data

Site Name: Shields River

9/19/00

Site ED: McCloud station
Taxon

Approx. percent
Quantity

of sample used:
Percent

17

HBI

FFG

Polycelis coronata
Nais vanabilis

1

1

0.31
0.31

4
8

CG
CG

Total Misc. Taxa

2

0.62

Baetis tricaudatus
Diphetor hageni
Caudatella helerocaudala
Drunella doddsi
Drunella grandis
Ephemerella sp.
Cinygmula sp.
Rhithrogena sp

2
1
4
6
4
9
38
16

0.62
031
1.24
1.86
1.24
2.80
II 80
4.97

CG
CG
CG
CG
CG
CG
SC
SC

Total Epbemeroptera

80

24.84

Sweltsa sp
Zapada cwctipes
Zapada columbiana
Claassenia sabulosa
Doroneuria sp
Hesperoperla pacifica
Perlodidae-early instar
Skwala sp

2
22
1
2
4
14
2
2

0.62
683
0.31
0.62
1 24
4,35
0,62
0,62

PR
SH
SH
PR
PR
PR
PR
PR

Total Plecoptera

49

15.22

Arctopsyche grandis
Brachycentrus amencamis
Micrasema sp
Glossosoma sp
Hydropsyche sp

Lepidosloma sp.-sand case larvae
Rhyacophila-early mslar
Rhyacophila Brunnea Gr
Rhyacophila Coloradensis Gr.

Cricotopus nostococtadius

Micropsectra sp

Orthocladius sp

Pa gas ti a sp

Tvetenia sp

12

10

5

41

27

28

1

6

5

3,73
3 11
1.55
12 73
839
8.70
0,31
1.86
1 55

9

1

23

6

2.80
0.31
7,14
1 86
0,31

PR
OM
MH
SC
CF
SH
PR
PR
PR

Total Trichoptera

135

41.93

Heterlimnnis sp
Narpus sp
Optioservus sp

1
1
8

0.31
0.31
2.48

4
4
4

CG
CG
SC

Total Coleoptera

10

3.11

Simulium sp
Anlocha sp
Hexatoma sp

2
2
2

0.62
0,62
0,62

6

3
2

CF
CG

PR

Total Diptera

6

1.86

3

PH

7

CG

6

CG

1

CG

5

CG

Total ChiroDomidae

40

12.42

Grand Total

322

100.00

Aquatic Macroinvertebrate Summary Data

9/19/00

Site NameiShields River

Site ID: Johnstone station

TOTAL ABUNDANCE
Ephemeroptera + Plecoptera +
Trichoptera (EPT) abundance

TOTAL NUMBER OF TAXA
Number EPT laxa

TAXONOMIC GROUP COMPOSITION

328

132

20
8

GROUP

Misc. Taxa

Odonata

Ephemeroptera

Plecoptera

Hemiptera

Megaloptera

Trichoptera

Lepidoptera

Coleoptera

Diptera

Chrionomidae

#TAXA ABUNDAN PERCENT

2

35

10.67

0

0

0.00

3

3

0.91

1

1

0.30

0

0

0.00

0

0

0.00

4

128

39.02

0

0

0.00

3

47

14.33

2

4

1.22

5

110

33.54

CONTRIBUTION OF DOMINANT TAXA

TAXON ABUNDANCE

Hydropsyche sp

Orthocladius sp

Optioservus sp.

Physidae

Lepidostoma sp.-sand case larv.

SUBTOTAL 5 DOMINANTS

Amiocentrus aspilus

Chcolopus sp.

Zaitzevia sp.

Eukiefferiella Pseudomontana C

Acan

TOTAL DOMINANTS

SAPROBIC INDICES
Hilsenhoff Biotic Index

;cE :

PERCENT

95

28.96

91

27.74

37

11.28

32

9.76

18

5.49

273

83.23

14

4.27

11

3.35

9

2.74

5

1.52

3

091

315

9603

4.89

RATIOS OF TAX GROUP ABUNDANCES
EPT/Chironorrudae

1.20

FUNCTIONAL FEEDING GROUP (FFG) COMPOSITION

GROUP #TAXA ABUNDAN PERCENT

Predator

Parasite

Collector-gatherer

Collector-filterer

Macroph>1e-herbivore

Piercer-herbivore

Scraper

Shredder

Xylophage

Ommvore

Unknown

RATIOS OF FFG ABUNDANCES
Scraper/Collector-filterer
Scraper/(Scraper + C filterer)
Shredder/Total organisms

2

4

1.22

1

3

0.91

0

163

49.70

1

95

28.96

0

0

0.00

0

0

0.00

3

39

11.89

1

18

5.49

0

0

0.00

2

6

1.83

0

0

0.00

0.41
0.29
0.02

DFVERSrrY MEASURES
Shannon H (loge)
Shannon H (log2)
Evenness
Simpson D

1.66
2.39
0.55
0.16

COMMUNITY VOLTINISM ANALYSIS
TYPE ABUNDANCE PERCENT

Multivoltine 109 33 31

Umvoltine 171 52.06

Semivoltine 48 14.63

Tolerant
Intolerant
C linger

#TAXA ABUNDANCE PERCENT

6 85 25.91

0 0 000

10 171 52.13