PNAMP Macroinvertebrate Planning Group, 2012-04-13
Literature review focused on literature that informs the topics of protocol comparisons and the
relationships of macroinvertebrates to habitat and fish productivity
(Compiled from submittals from planning group participants; contact Kathryn Thomas with comments or
additional submittals. Copies of individual articles are available by request for those that cannot access
them directly. Kathryn_a_thomas@usgs.gov)
Keyword index: TO BE DEVELOPED (SUGGESTIONS WELCOMED)
Bailey, R.C., R.H. Norris, and T.B. Reynoldson. 2004.
Bioassessment of Freshwater Ecosystems: Using the Reference Condition Approach.
Norwell, MA: Kluwer Academic Publishers.
Keywords: Benthic macroinvertebrates as indicators of fish habitat quality
Abstract: Aquatic ecosystem assessment is a rapidly developing field, and one of the newer approaches to
assessing the condition of rivers and lakes is the Reference Condition Approach. This is a significant advancement
in biomonitoring because it solves the problem of trying to locate nearby control or reference sites when studying
an ecosystem that may be degraded, a problem that bedevils traditional approaches. Rather than using upstream
reference sites in a river system or next-bay-over references sites in a lake, an array of ecologically similar, leastexposed to stress sites scattered throughout a catchment or region is used. Once the reference condition has been
established, any site suspected of being impacted can be assessed by comparison to the reference sites, and its
status determined. The Reference Condition database, once formed, can be used repeatedly.
The Reference Condition is established by standardized sampling of both the biota and its environment at
a number of reference sites. A variety of environmental variables is measured in conjunction with sampling the
biota (usually benthic invertebrates). Bioassessment of Freshwater Ecosystems describes the basic methods
involved in selecting and sampling appropriate reference sites, comparing test sites to appropriate reference sites
using predictive modeling, and determining whether or not test sites are in the reference condition. This provides
a rapid assessment method that can deal with everything from large-scale, national issues to local-scale problems
with the same approach, and often parts of the same database.
Baxter, C. V, K. D Fausch, M. Murakami, and P. L Chapman. 2004.
Fish Invasion Restructures Stream and Forest Food Webs by Interrupting Reciprocal Prey Subsidies.
Ecology 85 (10): 2656–2663.
Keywords: Trophic interactions between macroinvertebrates and fish
Abstract: Habitat alteration and biotic invasions are the two leading causes of global environmental change and
biodiversity loss. Recent innovative experiments have shown that habitat disturbance can have drastic effects that
cascade to adjacent ecosystems by altering the flow of resource subsidies from donor systems. Likewise, exotic
species invasions could alter subsidies and affect distant food webs, but very few studies have tested this
experimentally. Here we report evidence from a large-scale field experiment in northern Japan that invasion of
nonnative rainbow trout (Oncorhynchus mykiss) interrupted reciprocal flows of invertebrate prey that drove
stream and adjacent riparian forest food webs. Rainbow trout usurped terrestrial prey that fell into the stream,
causing native Dolly Varden charr (Salvelinus malma) to shift their foraging to insects that graze algae from the
stream bottom. This indirectly increased algal biomass, but also decreased biomass of adult aquatic insects
emerging from the stream to the forest. In turn, this led to a 65% reduction in the density of riparian-specialist
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spiders in the forest. Thus, species invasions can interrupt flows of resources between interconnected ecosystems
and have effects that propagate across their boundaries, effects that may be difficult to anticipate without indepth understanding of food web relationships.
Bayley, P.B., and H.W. Li. 2008.
Stream Fish Responses to Grazing Exclosures.
North American Journal of Fisheries Management 28 (1): 135–147.
Keywords: Trophic interactions between macroinvertebrates and fish
Abstract: Eight paired reaches of northeastern Oregon streams were selected such that one reach was an
established livestock exclosure and a neighboring, geomorphologically similar reach was open to grazing.
Exclosures varied in length from 123 to 436 m. Teams of snorkelers recorded fish species and size-groups in the
enclosure and grazed reaches simultaneously so that diurnal changes in fish behavior did not confound results.
Observed densities of age-0 redband trout Oncorhynchus mykiss in pools, corrected for snorkeler range of vision,
were significantly different (P , 10_9), increasing by an average of 2.5-fold in exclosed reaches. Conversely,
warmwater fishes (dominated by speckled dace Rhinichthys osculus) were negatively related to exclosures (P ,
0.001). Densities of age-0 warmwater fish and age-0 O. mykiss were uncorrelated (P ¼ 0.18). No first-order
interactions existed among exclosure –control treatment, stream, and pool temperature variables in either age-0
analysis. Combined juvenile and adult O. mykiss results indicated significant interactions between several streams
and temperature and only a marginal effect (P ¼ 0.05) of exclosure. No significant exclosure effect existed on
combined juvenile and adult warmwater fish (P . 0.90).The greater density of age-0 O. mykiss in exclosures was
attributed to the potential food supply and cover due to increases in undercut banks, instream bank vegetation,
width : depth ratio, and several riparian vegetation variables. Bioenergetic and scale arguments are presented that
are consistent with the failure to detect a parallel effect with juvenile and adult O. mykiss. A marginally significant
(P¼0.04) mean drop in pool water temperature of 0.78C in exclosures was observed, but continual temperature
monitoring indicated no significant difference (P . 0.50) between reaches in 7-d means of daily maxima or minima.
These results are promising with respect to improvement of salmonid habitat through prevention of grazing, but
the exclosures are too small and infrequent to be effective at the population or basin-wide level.
Blocksom, K.A., B.C. Autrey, M. Passmore, and L. Reynolds. 2008.
A Comparison of single and multiple habitat protocols for collecting macroinvertebrates in wadeable
streams.
J. of the American Water Resources Association 44(3): 557- 593.
Keywords:
ABSTRACT: In 2003, we compared two benthic macroinvertebrate sampling methods that are used for rapid
biological assessment of wadeable streams. A single habitat method using kick sampling in riffles and runs was
compared to a multiple habitat method that sampled all available habitats in proportion of occurrence. Both
methods were performed side-by-side at 41 sites in lower gradient streams of the Piedmont and Northern
Piedmont ecoregions of the United States, where riffle habitat is less abundant. Differences in sampling methods
were examined using similarity indices, two multimetric indices [the family-level Virginia Stream Condition Index
(VSCI) and the species-level Macroinvertebrate Biotic Integrity Index (MBII)], their component metrics, and
bioassessment endpoints based on each index. Index scores were highly correlated between single and multiple
habitat field methods, and sampling method comparability, based on comparison of similarities between and
within sampling methods, was particularly high for species level data. The VSCI scores and values of most of its
component metrics were not significantly higher for one particular method, but relationships between single and
multiple habitat values were highly variable for percent Ephemeroptera, percent chironomids, and percent
Plecoptera and Trichoptera (Hydropsychidae excluded). A similar level of variability in the relationship was
observed for the MBII and most of its metrics, but Ephemeroptera richness, percent individuals in the dominant
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five taxa, and Hilsenhoff Biotic Index scores all exhibited differences in values between single and multiple habitat
field methods. When applied to multiple habitat samples, the MBII exhibited greater precision, higher index
scores, and higher assessment categories than when applied to single habitat samples at the same sites. In streams
with limited or no riffle habitats, the multiple habitat method should provide an adequate sample for biological
assessment, and at sites with abundant riffle habitat, little difference would be expected between the single and
multiple habitat field methods. Thus, in geographic areas with a wide variety of stream types, the multiple habitat
method may be more desirable. Even so, the variability in the relationship between single and multiple habitat
methods indicates that the data are not interchangeable, and we suggest that any change in sampling method
should be accompanied by a recalibration of any existing assessment tool (e.g., multimetric index) with data
collected using the new method, regardless of taxonomic level.
Bryce, S. A, G. A Lomnicky, P. R. Kaufmann, L. S McAllister, and T. L Ernst. 2008.
Development of Biologically Based Sediment Criteria in Mountain Streams of the Western United States.
North American Journal of Fisheries Management 28 (6): 1714 – 1724.
Keywords: Benthic macroinvertebrates as indicators of fish habitat quality
Abstract: Sediment has long been recognized as a leading cause of impairment of biological condition in rivers and
streams of the United States. Recently, federal and state agencies have shown increased interest in developing
sediment criteria to maintain or improve habitat quality for the protection of aquatic species. To develop
biologically based sediment criteria, sediment amounts must be linked with aquatic vertebrate response. For our
analysis, we related an aquatic vertebrate index of biotic integrity (IBI) with a measure of the areal percentage of
streambed surficial fines (_0.06 mm). The association suggested that fine sediment limits the biological potential of
mountain streams. We used quantile regression to model the upper limit of IBI response; the regression equation
predicted a 4.7% decline in IBI for each 10% increase in areal surficial fines. However, the limiting relationship itself
did not suggest a specific sediment level above which impairment was evident. To develop more specific evidence
regarding sediment impairment and to describe possible impairment thresholds along the continuous relationship,
we sought additional information from (1) the range of areal percent fines at the 169 least disturbed reference
sites in our sample, (2) sediment tolerance values calculated for sediment-sensitive salmonids in the Mountains
ecoregion, (3) a review of studies that describe IBI scores representing very good to excellent condition in
coldwater (trout) streams of the United States, and (4) a second literature review of laboratory and field research
relating the effects of sediment on the survival of salmonid eggs. Placing our initial results in the context of this
additional information, we concluded that streambed areal surficial fine sediment (particle size _ 0.06 mm) levels
of 5% or less retain habitat potential for sediment-sensitive aquatic vertebrates in mountain streams. We offer
these results as scientific guidance for the process of establishing sediment criteria.
Bryce, S. A., G. A. Lomnicky, and P. R. Kaufmann. 2010.
Protecting Sediment-sensitive Aquatic Species in Mountain Streams Through the Application of
Biologically Based Streambed Sediment Criteria.
Journal of the North American Benthological Society 29 (2) (June): 657–672. doi:10.1899/09-061.1.
Keywords: Benthic macroinvertebrates as indicators of fish habitat quality
Abstract: We evaluated several lines of evidence to identify bedded fine sediment levels that should protect and
maintain self-sustaining populations of native, sediment-sensitive aquatic species in the western US. To identify
these potential criterion values for streambed sediments ƒ0.06 mm (fines) and ƒ2 mm (sand and fines) diameter,
we examined: 1) the range of areal % fines and areal % sand and fines values at 169 least-disturbed reference sites
in our sample, 2) sediment tolerance values calculated for a selection of sediment-sensitive aquatic vertebrate and
macroinvertebrate taxa for both particle size ranges, 3) quantile regression predictions of the declines in
vertebrate and macroinvertebrate Indices of Biotic Integrity (IBIs) at progressively higher ambient levels of
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streambed sediment from synoptic survey data acquired in 557 mountain stream sampling sites in 12 western
states, 4) a literature review of the effects of sand and fines on the survival of salmonid eggs to hatching, and 5) a
literature review of studies that quantitatively linked macroinvertebrate response to the pertinent size ranges of
streambed sediment in mountain streams. Predicted maximum vertebrate Index of Biotic Integrity (IBI) declined
4.4 points (SE = 1.0) and macroinvertebrate IBI declined 4.0 points (SE = 0.60) for each 10% increase in % fines.
Similarly, for each 10% increase in % sand and fines, the predicted maximum vertebrate IBI decreased 3.7 points
(SE = 0.50) and macroinvertebrate IBI decreased 3.0 points (SE = 0.50). Combining all lines of evidence, we
concluded that for sediment-sensitive aquatic vertebrates, minimum-effect sediment levels were 5% and 13% for
% fines and % sand and fines, respectively, both expressed as areal percentages of the wetted streambed surface.
For aquatic macroinvertebrates, minimum-effect levels for the 2 sediment size classes were 3% and 10%,
respectively. We encourage managers to consider these biologically based minimum effect values when
developing sediment criteria for mountain streams. Quantifying and comparing both vertebrate and
macroinvertebrate assemblage responses to streambed sedimentation informs the criteria setting process and
allows managers to set stream restoration priorities.
Bjornn, T. C. Bjornn, M. A. Brusven, and W. F. A. Duncan. 1989.
Energy-flow Response Models for Evaluation of Altered Riparian Vegetation in Three Southeast Alaskan
Streams.
Water Research 23 (8): 965.
Keywords: Trophic interactions between macroinvertebrates and fish
Abstract: First approximation production-response models to riparian vegetation alteration for low order
southeast Alaskan streams are presented. The models reflect negative and positive production responses with
respect to estimated maximum production values (kcal). Using the models we predict the response of
autochthonous of allochthonous production, benthic and terrestrial macroinvertebrate production, and potential
salmonid tissue elaboration to variation in riparian cover, riparian composition and stream nutrients. Higher
amounts of net usable allochthonous input are predicted with increasing riparian cover and percentage deciduous
composition. Autochthonous production and net usable allochthonous production form the primary energy base
of the stream ecosystem and are linked via energy transfer coefficients to higher trophic levels, e.g. benthic
macroinvertebrate (BMI) production. Like the energy transfer coefficients derived for autochthonous and
allochthonous production, the terrestrial invertebrate and salmonid production estimates are first approximations
and require validation. These models provide resource managers with criteria to assess probable consequences of
different riparian management strategies on fisheries resources in S.E. Alaska.
Budy, P., M. Baker, and S. K. Dahle. 2011.
Predicting Fish Growth Potential and Identifying Water Quality Constraints: A Spatially-Explicit
Bioenergetics Approach.
Environmental Management 48 (4) (July 17): 691–709.
Keywords: Trophic interactions between macroinvertebrates and fish
Abstract: Anthropogenic impairment of water bodies represents a global environmental concern, yet few
attempts have successfully linked fish performance to thermal habitat suitability and fewer have distinguished
covarying water quality constraints. We interfaced fish bioenergetics, field measurements, and Thermal Remote
Imaging to generate a spatially-explicit, high-resolution surface of fish growth potential, and next employed a
structured hypothesis to detect relationships among measures of fish performance and co-varying water quality
constraints. Our thermal surface of fish performance captured the amount and spatial-temporal arrangement of
thermally-suitable habitat for three focal species in an extremely heterogeneous reservoir, but interpretation of
this pattern was initially confounded by seasonal covariation of water residence time and water quality.
Subsequent path analysis revealed that in terms of seasonal patterns in growth potential, catfish and walleye
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responded to temperature, positively and negatively, respectively; crappie and walleye responded to eutrophy
(negatively). At the high eutrophy levels observed in this system, some desired fishes appear to suffer from
excessive cultural eutrophication within the context of elevated temperatures whereas others appear to be largely
unaffected or even enhanced. Our overall findings do not lead to the conclusion that this system is degraded by
pollution; however, they do highlight the need to use a sensitive focal species in the process of determining
allowable nutrient loading and as integrators of habitat suitability across multiple spatial and temporal scales. We
provide an integrated approach useful for quantifying fish growth potential and identifying water quality
constraints on fish performance at spatial scales appropriate for whole-system management.
Clough, J.S. 2009
AQUATOX (Release 3): Modeling Environmental Fate and Ecological Effects in Aquatic Ecosystems.
Washington DC. Available through: http://water.epa.gov/scitech/datait/models/aquatox/index.cfm
Keywords: Benthic macroinvertebrates as indicators of fish habitat quality, Trophic interactions
between macroinvertebrates and fish
Abstract: AQUATOX is a simulation model for aquatic systems. AQUATOX predicts the fate of various pollutants,
such as nutrients and organic chemicals and their effects on the ecosystem, including fish, invertebrates, and
aquatic plants. This model is a valuable tool for ecologist, biologists, water quality modelers, and anyone involved
in performing ecological risk assessments for aquatic ecosystems.
Deal, R.L. 2007.
Management Strategies to Increase Stand Structural Diversity and Enhance Biodiversity in Coastal
Rainforests of Alaska.
Biological Conservation 137: 520–532.
Keywords: Trophic interactions between macroinvertebrates and fish
Abstract: Coastal rainforests of southeast Alaska have relatively simple species composition but complex
structures with high diversity of tree ages, sizes and forest canopy layers, and an abundant understory plant
community. Wildlife and fisheries resources also play an important role in the ecological functioning of forest and
aquatic systems. Clearcutting has greatly altered these forest ecosystems with significant decreases in structural
diversity of forest stands and greatly reduced wildlife habitat. This paper synthesizes information on management
options in older forests that have never been actively managed, and in younger forests to increase diversity of
stand structures and their associated effects on biodiversity. Light to moderate levels of partial cutting in oldgrowth forests can maintain the original diversity of overstory stand structures and understory plant communities.
In younger forests that develop after clearcutting, mixed alder-conifer stands provide more heterogeneous
structures and significantly higher understory biomass than in pure conifer forests. Research has shown that red
alder increases diversity and abundance of understory plants, and provides forage for deer and small mammals.
Results also show a clear linkage between alder and improved invertebrate diversity in aquatic systems. A
combination of light partial cutting in older forests along with inclusion of red alder in conifer-dominated forests
could provide the greatest amount of diversity and maintain the complex stand structures that are an important
component of these forest ecosystems.
Duncan, W, M Brusven, and T Bjornn. 1989.
Energy-flow Response Models for Evaluation of Altered Riparian Vegetation in Three Southeast Alaskan
Streams.
Water Research 23 (8) (August): 965–974.
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Keywords: Trophic interactions between macroinvertebrates and fish
Abstract: First approximation production-response models to riparian vegetation alteration for low order
southeast Alaskan streams are presented. The models reflect negative and positive production responses with
respect to estimated maximum production values (kcal). Using the models we predict the response of
autochthonous of allochthonous production, benthic and terrestrial macroinvertebrate production, and potential
salmonid tissue elaboration to variation in riparian cover, riparian composition and stream nutrients. Higher
amounts of net usable allochthonous input are predicted with increasing riparian cover and percentage deciduous
composition. Autochthonous production and net usable allochthonous production form the primary energy base
of the stream ecosystem and are linked via energy transfer coefficients to higher trophic levels, e.g. benthic
macroinvertebrate (BMI) production. Like the energy transfer coefficients derived for autochthonous and
allochthonous production, the terrestrial invertebrate and salmonid production estimates are first approximations
and require validation. These models provide resource managers with criteria to assess probable consequences of
different riparian management strategies on fisheries resources in S.E. Alaska.
Flinders, C.A., R.J. Horwitz, and T. Belton. 2008.
Relationship of Fish and Macroinvertebrate Communities in the mid-Atlantic Uplands: Implications for
Integrated Assessments.
Ecological Indicators 8: 588–598.
Keywords: Benthic macroinvertebrates as indicators of fish habitat quality
Abstract: Indices developed for stream bioassessment are typically based on either fish or macroinvertebrate
assemblages. These indices consist of metrics which subsume attributes of various species into aggregate
measures reflecting community-level ecological responses to disturbance. However, little is known about the
relationship between fish and macroinvertebrate metrics, or about how ecological health assessments are affected
by assemblage specific responses to disturbance. We used principal component analysis (PCA) and regression
analysis of existing fish (n = 371) and macroinvertebrate (n = 442) stream bioassessment data from a multi-source
dataset to determine broad scale, within-assemblage metric patterns, and to examine the intercorrelation of fish
and macroinvertebrate metrics (n = 246) and their response to watershed area and land use/land cover gradients.
Fish and macroinvertebrate metrics expressed as principal components (PCs) accounted for 72.4 and 85.4% of
dataset variance, respectively, with PC-metric patterns reflecting aspects of stream impairment including water
and habitat quality. Model components predicting fish metric response differed among fish PCs, with watershed
area and macroinvertebrate metric response strongly correlated with the first fish PC, and remaining fish PC
models consisting of watershed area, land use, and macroinvertebrate PCs. Correlation between fish and
macroinvertebrate PCs, and models relating fish and macroinvertebrate PCs generally explained less variation (13–
27%) than metric response models of fish (25–34%) and macroinvertebrates (8–38%) to watershed area and land
use/land cover variables. Best-response models integrating fish and macroinvertebrate PCs, watershed area, and
land use/land cover variables accounted for the greatest variation in fish PCs (32–50%) across sites. Because fish
and macroinvertebrate metrics provide different information on ecological condition, integrated use of
information from multiple groups may be appropriate when developing monitoring programs.
Gerth, W. J. and A. T. Herlihy. 2006.
Effect of sampling different habitat types in regional macroinvertebrate bioassessment surveys.
J.N. Am.Benthol. Soc. 25(2): 501-512
Keywords:
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Abstract: One of the dilemmas in designing any large-scale macroinvertebrate bioassessment is deciding where to
sample within streams. Streams contain a wide variety of habitats with varying macroinvertebrate assemblages,
yet consistency in sampling protocol is needed to interpret results across sites in a region. The Environmental
Monitoring and Assessment Program (EMAP) conducted large regional probability surveys in the mid-Atlantic
(1993–1998) and the western US (2000–2001). In these surveys, 2 macroinvertebrate sample types were collected
at each site: pool and riffle in the mid-Atlantic region, and reachwide and riffle in the western US. We analyzed
data from sites where both types of samples had been collected (206 mid-Atlantic and 293 western US sites) to
examine the effects of sample type on typical metric and multivariate analyses done in bioassessments. Sample
types differed in terms of taxon richness measures and assemblage composition, and differences were more
pronounced between mid-Atlantic riffle and pool samples than between western US reachwide and riffle samples.
Nonetheless, sample-type differences did not obscure the overall pattern in ordination analyses, nor did they
influence detection of important environmental gradients. In addition, bioassessments based on Ephemeroptera,
Plecoptera, and Trichoptera taxon richness showed that regional assessments differed little with sample type. Our
analyses indicate that
typical bioassessment methods are relatively robust with respect to sample type in regional surveys. Reachwide
sampling could be used with little risk to the quality of assessments in surveys covering large geographic areas
where a single targeted habitat may not occur at all sites. Reachwide sampling is also easy to apply consistently at
most sites and requires approximately the same effort and cost as single-habitat sampling.
Grafe, C.S., C.A. Mebane, M.J. McIntyre, D.A. Essig, D.H. Brandt, and D.T. Mosier.
2002.
The Idaho Department of Environmental Quality Water Body Assessment Guidance, Second Edition Final.
Boise, ID: Idaho Department of Environmental Quality.
Available at: http://www.deq.idaho.gov/media/457010-wbag_02_entire.pdf
Keywords: Benthic macroinvertebrates as indicators of fish habitat quality
Abstract: This Water Body Assessment Guidance (WBAG) is intended as an analytical tool to
guide individuals through a standardized assessment process. The WBAG
describes Idaho Department of Environmental Quality (DEQ) methods used to
evaluate data and determine beneficial use support of Idaho water bodies. This
document is a revision of the 1996 WBAG (DEQ 1996).
Griffith, M.B., B.H. Hill, F.H. McCormick, P.R. Kaufmann, A.T. Herlihy, and A.R.
Selle. 2005.
Comparative Application of Indices of Biotic Integrity Based on Periphyton, Macroinvertebrates, and Fish
to Southern Rocky Mountain Streams.
Ecological Indicators 5: 117–136.
Keywords: Benthic macroinvertebrates as indicators of fish habitat quality
Abstract: To assess the relative sensitivity of assessments using community metrics for macroinvertebrates,
periphyton, and fish assemblages, we compared the results of three parallel assessments using these assemblages
at 86 stream reaches sampled in 1994 and 1995 by the Regional Environmental Monitoring and Assessment
Program (R-EMAP) in the mineralized zone or historical mining region of the Southern Rockies Ecoregion in
Colorado. We contrasted assessments using community metrics for each taxa group selected to be diagnostic of
the two large-scale stressor gradients identified in this ecoregion: discharges from historical hardrock metal mines
and agriculture, particularly pasturing of livestock. While principal components analysis (PCA) extracted axes from
the metrics for all three assemblages correlated with increased metal concentrations, the axes differed in their
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sensitivity to different environmental gradients. Two axes extracted from the fish metrics were correlated with
dissolved metals, suspended solids, and sediment embeddedness or with sediment metals. Two axes extracted
from the macroinvertebrate metrics partially separated these two stressor gradients, while the single correlated
axis extracted from the periphyton metrics did not. The second macroinvertebrate PCA axis was correlated with an
environmental gradient correlated both with agricultural effects and with stream size, as were the second and
third periphyton PCA axes. The third fish PCA axis was correlated with stream size and slope, but was not sensitive
to agricultural effects. Fish, macroinvertebrates, and periphyton differ in their sensitivity to different stressors, and
combining metrics for these assemblages into a mixed assemblage index of biotic integrity may increase the utility
of the multimetric approach to diagnose environmental stressors at impaired reaches.
Hawkins, C. P, R. H Norris, J. N Hogue, and J. W Feminella. 2000.
Development and Evaluation of Predictive Models for Measuring the Biological Integrity of Streams.
Ecological Applications 10 (5): 1456–1477.
Keywords: Benthic macroinvertebrates as indicators of fish habitat quality
Abstract: The ratio of the number of observed taxa to that expected to occur in the absence of humancaused stress (OIE) is an intuitive and ecologically meaningful measure of biological integrity. We
examined how OIE ratios derived from stream invertebrate data varied among 234 unimpaired
reference sites and 254 test sites potentially impaired by past logging. Data were collected from streams
in three montane ecoregions in California. Two sets of River Invertebrate Prediction and Classification
System (RIVPACS) predictive models were built: one set of models was based on near-species taxonomic
resolution; the other was based on family identifications. Two models were built for each level of
taxonomic resolution: one calculated 0 and E based on all taxa with probabilities of capture (Pj) > 0; the
other calculated 0 and E based on only those taxa with Pc ≥ 0.5. Evaluations of the performance of each
model were based on three criteria: (1) how well models predicted the taxa found at unimpaired sites,
(2) the degree to which OIE values differed among unimpaired reference sites and potentially impaired
test sites, and (3) the degree to which test site OIE values were correlated with independent measures
of watershed alteration. Predictions of species models were more accurate than those of family models,
and pre-dictions of the Pc ≥0.5 species model were more robust than predictions of the PC > 0 model.
OIE values derived from both species models were related to land use variables, but only assessments
based on the Pc > 0.5 model were insensitive to naturally occurring differences among streams,
ecoregions, and years.
Hayes, J. W., N. F. Hughes, and L. H. Kelly. 2007.
Process-based Modelling of Invertebrate Drift Transport, Net Energy Intake and Reach Carrying Capacity
for Drift-feeding Salmonids.
Ecological Modelling 207 (2-4) (October 10): 171–188.
Keywords: Trophic interactions between macroinvertebrates and fish
Abstract: We present an overview of a process-based modelling approach for predicting how change in
flow affects drift density, net rate of energy intake (NREI) and numbers of drift-feeding salmonids. It
involves linking an existing two-dimensional flow model (River2D) with models of invertebrate drift
transport and drift-foraging which we have developed. We describe, demonstrate and partially test our
models in an application on a 80m×20m pool on a New Zealand river. We show how these models
realistically capture hydraulic, drift dispersion and bioenergetics drift-foraging processes to predict the
relationship between stream flow, habitat quality and quantity (in terms of NREI), and carrying capacity
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for drift-feeding salmonids. Overall, the 2D hydraulic model made good predictions of water levels,
depths and water velocity at the calibration flow and a lower (validation) flow. The drift transport model
made good predictions of the spatial distribution of invertebrate drift density throughout the pool at
low flow after it was calibrated against observed drift density at the higher flow. The model correctly
predicted that drift density would decline downstream and into the margins due to the process of
settling dominating over entry from the stream bed, and that drift would be carried further downstream
and laterally as flow increased. The foraging model made a reasonable prediction (6–7) of the numbers
of 0.5m adult brown trout observed (5) in the pool. It accurately predicted that trout should be
distributed down the thalweg where net rate of energy intake (NREI) was highest, but when NREI was
adjusted for depletion by feeding fish the predicted drift-feeding locations were more closely spaced
(bunched) than observed fish locations. Our process based modelling approach has important
implications for improving biological realism in predictions of the response of drift-feeding fishes to flow
change within the context of the IFIM.
Herbst, D. B. and E. L. Silldorff. 2006.
Comparison of the performance of different bioassessment methods: similar evaluation of biotic
integrity from separate programs and procedures.
J. of the North American Benthological Society. 25(2): 513-530.
Keywords:
Abstract. Regional bioassessment programs of states, various federal agencies, and other governmental and
private groups often use different methods to collect and analyze stream invertebrate samples. This lack of
uniformity has created concern and confusion over the comparability of disparate sources of data, but few studies
have attempted to evaluate differences in performance between methods or to reconcile the results produced
from different methods. We conducted concurrent sampling at 40 sites in the eastern Sierra Nevada of California
using 3 bioassessment methods to obtain directly comparable data sets. The rifflebased methods (University of
California Sierra Nevada Aquatic Research Laboratory [UC-SNARL, Lahontan Water Board], California Stream
Bioassessment Protocol, and US Forest Service Region 5) differed at each stage from field sample collection to
laboratory processing and data analysis. We used a performance-based methods system to compare precision,
uniformity, discrimination, accuracy, and correlations among multimetric Index of Biotic Integrity (IBI) scores and
multivariate River Invertebrate Prediction and Classification System (RIVPACS)-type observed/expected (O/E)
ratios. Reference and test sites were identified using local and upstream-watershed disturbance criteria, and
invertebrate community measures and models were then developed to discriminate between reference and test
sites. The more intensive UC-SNARL method showed slightly, but consistently, greater sensitivity for discriminating
impairment than the other 2 methods. The UC-SNARL method produced greater differences between referenceand test-site means relative to lower reference-site standard deviations than the other 2 methods. However,
assessment scores were highly correlated among methods and distinguished reference from test sites with similar
accuracy among methods despite the slight differences in performance. Our results show that differing
bioassessment methods can yield very similar, effective discrimination of impaired biological condition even
though they have multiple differences in field and laboratory protocols (mesh size, replication, area sampled,
taxonomic resolution, total counts). Moreover, this conclusion did not depend on the approach taken to data
analysis because both multimetric IBIs and multivariate RIVPACS-type O/Es were in close agreement.
Methodological uniformity is important when coordinating monitoring programs, but our results suggest that data
from multiple sources could potentially be used interchangeably and for cross-validation of assessments of stream
biological integrity.
Hetrick, N. J., M. A. Brusven, W. R. Meehan, and T. C. Bjornn. 1998.
Changes in Solar Input, Water Temperature, Periphyton Accumulation, and Allochthonous Input and
Storage After Canopy Removal Along Two Small Salmon Streams in Southeast Alaska.
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Transactions of the American Fisheries Society 127 (6): 859–875.
Keywords: Benthic macroinvertebrates as indicators of fish habitat quality
Abstract: We assessed changes in availability and consumption of invertebrates by juvenile coho
salmon Oncorhynchus kisutch in a small stream in southeast Alaska where patches of dense secondgrowth riparian
vegetation bordering the stream had been removed. Benthic invertebrate populations were assessed during
summer 1988 and 1989 with a Hess sampler. Aerial invertebrates were sampled during summer 1989 with wiremesh sticky traps hung just above the water surface and with floating clear-plastic pan traps. Invertebrate drift was
assessed during summer 1989 with nets placed at the downstream end of closed- and open-canopy stream
sections. Diets of age-0 and age-1 coho salmon were sampled by flushing stomach contents of fish collected from
closed- and open-canopy stream sections. Abundance and biomass of benthic invertebrates were larger in openthan in closed-canopy stream sections and were primarily dipterans, ephemeropterans, and plecopterans. More
insects were caught on sticky traps in open than in closed sections on two of four dates sampled, and composition
of the catch was primarily dipterans (74% in both closed- and open-canopy sections). Catch rates of invertebrates
in the pan traps were significantly higher in closed than in open sections on 12 July and were greater in open than
in closed sections on 11 August. No significant canopy effect was detected with regard to dry weight of insects
captured in pan traps. Composition of the pan-trap catches was primarily dipterans in both closed and open
sections (65% and 72%). Abundance of invertebrates in the drift was significantly higher in closed sections than in
open sections on two of four dates sampled; dry weight of invertebrate drift did not differ significantly between
canopy types. Dry weight of stomach contents of age-0 and age-1 coho salmon was greater for fish sampled in
closed- than open-canopy sections on one of four dates sampled; no significant canopy effect was detected for the
other three dates sampled. Aerial insects were more abundant in drift and in diets of age-0 and age-1 coho salmon
in closed- than in open-canopy sections. Diet of age-0 coho salmon in both closed and open sections and diet of
age-1 fish in closed sections overlapped significantly with composition of the drift. Diet of age-1 coho salmon in
open sections, however, did not overlap significantly with drift, an indication of selectivity in feeding behavior.
Based on higher abundance of aerial invertebrates above the water surface and increased standing crop of benthic
invertebrates that we observed in open- versus closed canopy sections of Eleven Creek, it appears that canopy
removal has the potential to increase the carrying capacity of juvenile coho salmon in streams where populations
are food limited.
Hetrick, N. J., M. A. Brusven, T. C. Bjornn, R. M. Keith, and W. R. Meehan. 1998.
Effects of Canopy Removal on Invertebrates and Diet of Juvenile Coho Salmon in a Small Stream in
Southeast Alaska.
Transactions of the American Fisheries Society 127 (6): 876–888.
Keywords: Trophic interactions between macroinvertebrates and fish
Abstract: Changes in solar radiation, water temperature, periphyton accumulation, and allochthonous inputs and
storage were measured after we removed patches of deciduous, second-growth riparian vegetation bordering two
small streams in southeast Alaska that produce coho salmon Oncorhynchus kisutch. Solar radiation and leaf litter
input were measured at the water surface at random locations dispersed through six alternating closed- and opencanopy stream sections. Water temperature, periphyton, and stored organic samples were collected near the
downstream end of each section. Solar radiation intensity was measured with digital daylight integrators and
pyronometers, periphyton biomass and chlorophyll a were measured on red clay tile substrates, allochthonous
input was measured with leaf litter baskets, and benthic organic matter was measured with a Hess sampler.
Average intensity of solar radiation that reached the water surface of open canopy sections was significantly higher
than in closed-canopy sections of two streams measured during daylight hours in summer 1988 and of one stream
measured day and night in summer 1989. Average daily water temperature was similar in the two canopy types in
summer 1988, but was higher in open- than in closed-canopy sections in 1989. Accumulation of periphyton
biomass was significantly higher in open- than in closed-canopy sections of the two streams studied in the summer
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of 1988 and of the one stream sampled in 1989. Accrual of periphyton biomass on tiles placed in the stream for 30d colonization periods during the summer months of 1989 was also significantly higher in the open than closed
sections. Accumulation of chlorophyll a was significantly higher in the open- than in closed-canopy sections of the
two streams in 1988 but did not differ significantly between canopy types in 1989. Thirty-day accrual of chlorophyll
a was greater in open- than in closed-canopy sections of the one stream studied in 1989. Allochthonous input to
the streams decreased after canopy removal, but the amount of organic material stored in the substrate did not
differ significantly between open- and closed-canopy sections. Weather was predominantly overcast and rainy in
summer 1988 and mostly sunny with infrequent rain in 1989. We speculate that advective heat transfer and high
stream discharge from frequent rains moderated the effect of canopy removal and increased solar radiation on
water temperatures in open-canopy stream sections in 1988. In 1989, solar radiation was a significant factor in
regulating water temperature, especially when streamflows were low. Using a model, we predicted that water
temperatures would change little in a 160-m open-canopy reach of Eleven Creek during any weather condition
when flows were high. With low flows, however, stream temperatures in open sections of Eleven Creek were
predicted to exceed the optimum for growth of juvenile coho salmon in about 20 m during clear sunny weather
and in about 50 m when cloudy and overcast.
Hubler, S. 2009.
High Level Indicators of Oregon’s Forested Streams.
Oregon Department of Environmental Quality.
Available at: http://www.deq.state.or.us/lab/techrpts/docs/10-lab-003.pdf
Keywords: Benthic macroinvertebrates as indicators of fish habitat quality
Abstract: In January of 2007 the Oregon Board of Forestry endorsed the “Oregon Indicators of Sustainable Forest
Management” (OISFM; Oregon Department of Forestry, 2007). The document outlines seven environmental,
economic, and social strategies for measuring and discussing sustainable forestry management in Oregon. Each of
the seven strategies has a set of endorsed indicators that will be used by the Board of Forestry and other
Oregonians to evaluate Oregon’s progress towards sustainable Forest management.
This report provides information on two indicators outlined in OISFM “Strategy D: Protect, maintain, and
enhance the soil and water resources of Oregon’s forests.” The Oregon Water Quality Index (OWQI) is used to
evaluate objective “D.a. Water quality of forest streams”. The Predictive Assessment Tool for Oregon (PREDATOR),
a biological index using benthic macroinvertebrates, is used to assess objective “D.b. Biological integrity of forest
streams”. Both tools were developed by the Oregon Department of Environmental Quality (ODEQ) to evaluate the
status and trends of water quality and biological condition. The other indicator for Strategy D, “Forest road risks to
soil and water resources”, is not covered in this assessment.
Huhta, A., T. Muotka, A. Juntunen, and M. Yrjönen. 1999.
Behavioural Interactions in Stream Food Webs: The Case of Drift-feeding Fish, Predatory Invertebrates
and Grazing Mayflies.
Journal of Animal Ecology 68 (5): 917–927. doi:10.1046/j.1365-2656.1999.00339.x.
Keywords: Trophic interactions between macroinvertebrates and fish
Abstract: We examined direct and indirect behavioural responses of grazing mayfly nymphs (Baetis rhodani) to
predation risk from a drift-feeding fish (European min- now; odour manipulated), and two types of invertebrate
predators, Diura bicaudata (stonefly) and Rhyacophila nubila (caddis larva). We also assessed the direct responses
of the invertebrate predators to fish chemicals. 2. Based on diel gut content periodicity, D. bicaudata nymphs were
strongly nocturnal foragers. R. nubila was also nocturnal, but only in a fish stream; in a stream lacking fish, their
gut contents did not vary significantly on a diel basis. In the laboratory, Diura was nocturnal even in the absence of
fish and almost ceased moving when fish was present. Rhyacophila shifted from aperiodic to nocturnal foraging in
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the presence of fish. 3. The contrasting behaviours of the two predators may be explained by their respective field
distributions: D. bicaudata always co-occurs with fish, whereas R. nubila is also found in streams without fish.
Therefore, a capacity for plastic anti- fish responses is beneficial for R. nubila, but not for D. bicaudata. 4. Drift of
large Baetis nymphs was aperiodic when Rhyacophila was present, but nocturnal in all other treatments. Drift rate
was highest when both Diura and fish were present and lowest in treatments with Rhyacophila. Predatory
stoneflies, but not the caddis larva, induced a night-time peak in the drift of both Baetis size- classes. In the
absence of predators, small Baetis drifted aperiodically. Interaction terms in three-way ANOVAs testing for the
indirect effects of fish and invertebrate predators on mayfly drift periodicity and drift rate were all non-significant,
indicating that the response of Baetis to one type of predator was not modified by the other predator. 5. Our
results indicate that the drift periodicity of lotic mayflies may be fine-tuned to variations in the multi-predator
environment and that prey responses are size- specific. We conclude that the effects of invertebrate predators on
prey behaviour vary in relation to predator's foraging strategy and generalizations based on studies with only one
type of predator should be avoided.
ISAB. 2011.
ISAB Columbia River Basin Food Web Report, Document ISAB 2011http://www.nwcouncil.org/library/isab/2011-1/.
Keywords: Trophic interactions between macroinvertebrates and fish
Abstract: Food webs describe pathways by which energy, nutrients and other materials make their way to species
of cultural and economic interest. Food webs are often thought of as reflections of habitat, yet many other factors
shape the internal organization, linkages, productivity and resilience. Species diversity, the mix of native and nonnative species, chemical contaminants, habitat carrying capacity, nutrient delivery and cycling, competition,
predation, disease and associated system scale processes are all deeply involved in shaping food webs.
Nevertheless, highly complex food webs have been successfully manipulated at large scales to improve water
conditions as well as recreational fisheries while, at the same time ill-advised manipulations have resulted in
serious environmental issues – the introduction of mysids being one example.
The objectives of this report are to provide a fundamental understanding of aquatic food webs in the
Columbia River Basin and to illustrate and summarize their influences on native fish restoration efforts. The spatial
scope addresses tributaries, impoundments, the free-flowing Columbia and Snake rivers, as well as the estuary and
plume.
Johnson, J. H. 2007.
Comparative Diets of Subyearling Chinook Salmon (Oncorhynchus Tshawytscha) and Steelhead (O.
Mykiss) in the Salmon River, New York.
Journal of Great Lakes Research 33 (4): 906–911. doi:10.3394/03801330(2007)33[906:CDOSCS]2.0.CO;2.
Keywords: Trophic interactions between macroinvertebrates and fish
Abstract: Chinook salmon (Oncorhynchus tshawytscha) and steelhead (O. mykiss) have established naturalized
populations throughout the Great Lakes. Young-of-year of these species occur sympatrically for about one month
in Lake Ontario tributaries. This study examined the diets of subyearling Chinook salmon and steelhead relative to
available food in the Salmon River, New York. Terrestrial invertebrates and trichopterans were the major prey of
Chinook salmon, whereas steelhead fed primarily on baetid nymphs and chironomid larvae. Diet overlap was low
(0.45) between the species. The diet of Chinook was closely associated to the composition of the drift (0.88).
Steelhead diet drew equally from the drift and benthos during the first year of the study, but more closely
matched the benthos during the second year. Differences in prey selection, perhaps associated with differences in
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fish size, in addition to apparent differences in feeding mode (drift versus benthic), likely reduce competitive
interactions between these species.
Karr, J.R. 1991.
Biological Integrity: a Long-neglected Aspect of Water Resource Management.
Ecological Applications 1 (1): 66–84.
Keywords: Benthic macroinvertebrates as indicators of fish habitat quality
Abstract: Water of sufficient quality and quantity is critical to all life. Increasing human population and growth of
technology require human society to devote more and more attention to protection of adequate supplies of water.
Although perception of biological degradation stimulated current state and federal legislation on the quality of
water resources, that biological focus was lost in the search for easily measured physical and chemical surrogates.
The "fishable and swimmable" goal of the Water Pollution Control Act of 1972 (PL 92-500) and its charge to
"restore and maintain "biotic integrity illustrate that
law's biological underpinning. Further, the need for operational definitions of terms like" biological integrity" and
"unreasonable degradation "and for ecologically sound tools to measure divergence from societal goals have
increased interest in biological monitoring. Assessment of water resource quality by sampling biological
communities in the field (ambient biological monitoring) is a promising approach that requires expanded use of
ecological expertise. One such approach, the Index of Biotic Integrity (IB I), provides a broadly based,
multiparameter tool for the assessment of biotic integrity in running waters. IBI based on fish community
attributes has now been applied widely in North America. The success of IBI has stimulated the development of
similar approaches using other aquatic taxa. Expanded use of ecological expertise in ambient biological monitoring
is essential to the protection of water resources. Ecologists have the expertise to contribute significantly to those
programs
Kawaguchi, Y., Y. Taniguchi, and S. Nakano. 2003.
Terrestrial Invertebrate Inputs Determine the Local Abundance of Stream Fishes in a Forested Stream.
Ecology 84 (3): 701–708.
Keywords: Trophic interactions between macroinvertebrates and fish
Abstract: Transfer of energy from more productive donor habitats is frequently significant for the maintenance of
consumers in the recipient habitats. Nevertheless, the connection between the distribution of consumers and
allochthonous inputs has not been directly examined by field experiment. We present experimental evidence that
terrestrial invertebrate inputs directly influence the distribution of stream fishes in a forested headwater stream.
When terrestrial invertebrate input to the stream was experimentally reduced by using greenhouse covers, fish
biomass also decreased dramatically. Despite the greater amounts of input in the control than in the reduced
treatments, terrestrial invertebrates made up ~90% of stomach contents in both treatments during the study
period. Moreover, no difference in fish growth rates was evident between the treatments. These results provide
experimental evidence that the flow of such allochthonous resources in the donor-controlled system can explain
the distribution and dynamics of the consumer populations.
Kiernan, J.D., B.N. Harvey, and M.L. Johnson. 2010.
Direct Versus Indirect Pathways of Salmon-derived Nutrient Incorporation in Experimental Lotic Food
Webs.
Canadian Journal of Fisheries and Aquatic Sciences 67 (12): 1909–1924.
Keywords: Trophic interactions between macroinvertebrates and fish
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Abstract: The objective of our study was to examine how salmon carcass subsidization through alternative trophic
pathways affected stream food web productivity. Three salmon carcass treatments (dissolved carcass nutrients
only, dissolved carcass nutrients + carcass material, and a carcass-free control) were replicated five times in
artificial stream channels. We quantified changes in water chemistry and the production of periphyton,
macroinvertebrates, and age 0+ steelhead trout (i.e., sea-run rainbow trout, Oncorhynchus mykiss) over 65 days.
Dissolved ammonium and periphyton chlorophyll a concentrations increased for an approximate 2-week period in
both carcass-augmented treatments. However, there was no commensurate effect on periphyton ash-free dry
mass. Total macroinvertebrate biomass was significantly greater in the presence of nutrients + material after 65
days, but no such increase was observed in response to the addition of dissolved nutrients only. Despite modest
and inconsistent effects at lower trophic levels, both the nutrients only and nutrients + material treatments
increased the growth and condition of age 0+ steelhead trout, with significantly greater gains occurring in the
presence of nutrients + material. These data suggest that while salmon carcasses can enhance the short-term
growth of juvenile salmonids via bottom-up pathways, the availability and direct consumption of carcass biomass
may promote a substantial amount of additional production.
Matousek, John. 2007.
Predicting prey availability for stream salmonids.
Thesis, Humboldt State University. http://hdl.handle.net/2148/175
Keywords:
Abstract: In this study I evaluated the effectiveness of the percentage by mass of behaviorally drifting
invertebrates within drift samples to serve as an index of a stream’s capacity to support salmonid growth. I tested
hypotheses over seasonal timeframes that: 1) the taxonomic composition of stream salmonid diets corresponds
more closely with the composition of the drift than of the benthos; 2) the percentage by mass of behaviorally
drifting invertebrates in salmonid diets corresponds with the percentage of behaviorally drifting invertebrates in
drift samples; and 3) salmonid growth is positively correlated with the percentage by mass of behavioral drift. The
study was conducted in two 100-m reaches in each of six 2nd - 3rd order streams within the Smith and Klamath
River basins in coastal northern California. Stream reaches received experimental manipulations of canopy opening
and salmon carcass addition that produced sites differing in salmonid production. Within each reach, invertebrate
benthos, drift, and diets from resident cutthroat trout (Oncorhynchus clarki), and rainbow trout (Oncorhynchus
mykiss) were sampled three times each during summer and winter base flow conditions and seasonal
measurements of salmonid growth from PIT-tagged individuals were obtained. Taxonomic composition of the
salmonid stomach samples was not substantially similar to either the drift samples or the benthic samples.
Salmonids did not appear to be actively selecting for behaviorally drifting invertebrates and no relationship was
observed between the growth of juvenile salmonids and the percentage of behaviorally drifting invertebrates in
the drift. As such, the relative percent of behavioral drift was found to be insufficient as an index of prey
availability. Contributing to the difficulty of assessing prey availability was stream flow variability, seasonal and diel
abundance of other prey sources, incomplete taxonomic classification, and the opportunistic feeding behavior of
juvenile salmonids.
Macneale, K. H, P. M Kiffney, and N. L Scholz. 2010.
Pesticides, Aquatic Food Webs, and the Conservation of Pacific Salmon.
Frontiers in Ecology and the Environment 8 (9) (November): 475–482.
Keywords: Trophic interactions between macroinvertebrates and fish
Abstract: Pesticides pose complex threats to the biological integrity of aquatic ecosystems. In the western US,
pesticides have contaminated many surface waters that provide habitat for endangered salmon. These iconic
species depend on the productivity of rivers, lakes, and estuaries to provide food for juvenile growth, a key
determinant of subsequent marine survival. Despite extensive societal investments in salmon habitat restoration in
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recent years, the role of pesticides as a limiting factor for salmon recovery has received little attention. Pesticides
can be toxic to primary producers and macroinvertebrates, thereby limiting salmon population recovery through
adverse, bottom-up impacts on aquatic food webs. The integration of toxicology, environmental chemistry,
population biology, community ecology, landscape ecology, conservation biology, and environmental policy is
needed to better understand these indirect effects of pesticides on endangered species. We highlight key
information gaps and discuss how future research on pesticides and food webs can most effectively guide the longterm conservation of imperiled fish species.
Mebane, C.A. 2001.
Testing Bioassessment Metrics: Macroinvertebrate, Sculpin, and Salmonid Responses to Stream Habitat,
Sediment, and Metals.
Environmental Management and Assessment 67: 293–322.
Keywords: Benthic macroinvertebrates as indicators of fish habitat quality
Abstract: The purpose of this article is to report on the testing of responses of multimetric macroinvertebrate and
habitat indices to common disturbances to streams: stream habitat alteration, excessive sediment, and elevated
metals concentrations. Seven macroinvertebrate community metrics were combined into a macroinvertebrate
biotic index (MBI), and 11 channel morphology, riparian, and substrate features were combined into a habitat
index. Indices were evaluated by comparing the habitat results to fish population surveys and comparing the
macroinvertebrate results to habitat ratings, percent fine sediments measured by Wolman pebble counts, and
copper concentrations. Macroinvertebrate scores decreased with increasing percentages of fine sediments
measured either across the bankfull or instream channel widths. Macroinvertebrate scores decreased with
increasing copper. One metric, richness of Ephemeroptera, Plecoptera, and Trichoptera (EPT) taxa, was more
responsive to both copper and sediment than was the multimetric MBI. Habitat scores corresponded well with the
age class structure of salmonids, but not with that of benthic sculpins. Both salmonid and sculpin age classes
declined with increasing percentages of fine sediments. The decline was graded with the sculpin age classes,
whether fine sediments were measured across the instream or bankfull channel, whereas salmonids consistently
responded only to the instream fine sediments.
Mebane, C. A., T. R. Maret, and R.M. Hughes. 2003.
An Index of Biological Integrity (IBI) for Pacific Northwest Rivers.
Transactions of the American Fisheries Society 132 (March): 239–261. doi:10.1577/15488659(2003)132<0239:AIOBII>2.0.CO;2.
Keywords: Benthic macroinvertebrates as indicators of fish habitat quality
Abstract: The index of biotic integrity (IBI) is a commonly used measure of relative aquatic ecosystem condition;
however, its application to coldwater rivers over large geographic areas has been limited. A seven-step process
was used to construct and test an IBI applicable to fish assemblages in coldwater rivers throughout the U.S. portion
of the Pacific Northwest. First, fish data from the region were compiled from previous studies and candidate
metrics were selected. Second, reference conditions were estimated from historical reports and minimally
disturbed reference sites in the region. Third, data from the upper Snake River basin were used to test metrics and
develop the initial index. Fourth, candidate metrics were evaluated for their redundancy, variability, precision, and
ability to reflect a wide range of conditions while distinguishing reference sites from disturbed sites. Fifth, the
selected metrics were standardized by being scored continuously from 0 to 1 and then weighted as necessary to
produce an IBI ranging from 0 to 100. The resulting index included 10 metrics: number of native coldwater species,
number of age-classes of sculpins Cottus spp., percentage of sensitive native individuals, percentage of coldwater
individuals, percentage of tolerant individuals, number of alien species, percentage of common carp Cyprinus
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carpio individuals, number of selected salmonid age-classes, catch per unit effort of coldwater individuals, and
percentage of individuals with selected anomalies. Sixth, the IBI responses were tested with additional data sets
from throughout the Pacific Northwest. Last, scores from two minimally disturbed reference rivers were evaluated
for longitudinal gradients along the river continuum. The IBI responded to environmental disturbances and was
spatially and temporally stable at over 150 sites in the Pacific Northwest. The results support its use across a large
geographic area to describe the relative biological condition of coolwater and coldwater rivers with low species
richness.
Meehan, W.R. 1996.
Influence of Riparian Canopy on Macroinvertebrate Composition and Food Habits of Juvenile Salmonids
in Several Oregon Streams.
Research Paper. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest
Research Station.
Keywords: Trophic interactions between macroinvertebrates and fish
Abstract: The community composition of macroinvertebrates and the feeding habits of juvenile salmonids were
studied in eight Oregon streams. Benthic, drift, sticky trap, and water trap samples were taken over a 3-year
period, along with stomach samples of the fish. Samples were taken in stream reaches with and without riparian
canopy. Both main effects fish diet versus macroinvertebrate composition in the environment, and canopies versus
noncanopied stream condition were highly significant, but probably not of practical importance in terms of the
amount of preferred food available to the fish. In all aquatic sample types, including fish stomachs, Diptera and
Ephemeroptera were the predominant invertebrates collected. In sticky trap and water trap samples, Diptera and
Collembola were the predominant orders, reflecting the input of terrestrial invertebrates.
Meissner, K. and T. Muotka. 2006.
The Role of Trout in Stream Food Webs: Integrating Evidence from Field Surveys and Experiments.
Journal of Animal Ecology 75 (2): 421–433.
Keywords: Trophic interactions between macroinvertebrates and fish
Abstract: 1. We evaluated the effects of brown trout on boreal stream food webs using field surveys and
enclosure/exclosure experiments. Experimental results were related to prey preference of uncaged trout in the
same stream, as well as to a survey of macroinvertebrate densities in streams with vs. without trout. Finally, we
assessed the generality of our findings by examining salmonid predation on three groups of macroinvertebrate
prey (chironomid midges, epibenthic grazers, invertebrate predators) in a meta-analysis. 2. In a preliminary
experiment, invertebrate predators showed a strong negative response to trout, whereas chironomids benefited
from trout presence. In the main experiment, trout impact increased with prey size. Trout had the strongest effect
on invertebrate predators and cased caddis larvae, whereas Baetis mayfly and chironomid larvae were unaffected.
Trout impact on the largest prey seemed mainly consumptive, because prey emigration rates were low and
independent of fish presence. Despite strong effects on macroinvertebrates, trout did not induce a trophic cascade
on periphyton. Uncaged trout showed a strong preference for the largest prey items (predatory invertebrates and
aerial prey), whereas Baetis mayflies and chironomids were avoided by trout. 3. Densities of invertebrate
predators were significantly higher in troutless streams. Baetis mayflies also were less abundant in trout streams,
whereas densities of chironomids were positively, although non-significantly, related to trout presence. Metaanalysis showed a strong negative impact of trout on invertebrate predators, a negative but variable impact on
mobile grazers (mainly mayfly larvae) and a slightly positive impact on chironomid larvae. 4. Being size-selective
predators, salmonid fishes have a strong impact on the largest prey types available, and this effect spans several
domains of scale. Discrepancies between our experimental findings and those from the field survey and metaanalysis show, however, that for most lotic prey, small-scale experiments do not reflect fish impact reliably at
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stream-wide scales. 5. Our findings suggest that small-scale experiments will be useful only if the experimental
results are evaluated carefully against natural history information about the experimental system and interacting
species across a wide array of spatial scales.
Merz, J. E., and L. K. O. Chan. 2005.
Effects of Gravel Augmentation on Macroinvertebrate Assemblages in a Regulated California River.
River Research and Applications 21 (1) (January): 61–74. doi:10.1002/rra.819.
Keywords: Benthic macroinvertebrates as indicators of fish habitat quality
Abstract: Enhancement projects within anadromous salmonid rivers of California have increased in recent years.
Much of this work is intended as mitigation in regulated streams where salmon and steelhead spawning habitat is
inaccessible or degraded due to dams, water diversions and channelization. Little research has been done to assess
the benefits of spawning habitat enhancement to stream organisms other than salmon. We monitored benthic
macroinvertebrates at seven spawning gravel augmentation sites in the lower Mokelumne River, a regulated
stream in the Central Valley of California. Placement of cleaned floodplain gravel decreased depths and increased
stream velocities. Benthic organisms colonized new gravels quickly, equalling densities and biomass of unenhanced
spawning sites within 4 weeks. Macroinvertebrate species richness equalled that of unenhanced sites within 4
weeks and diversity within 2 weeks. Standing crop, as indicated by densities and dry biomass, was significantly
higher in enhancement sites after 12 weeks than in unenhanced sites and remained so over the following 10
weeks. Although mobile collector/browsers initially dominated new gravels, sedentary collectors were the most
common feeding category after 4 weeks, similar to unenhanced sites. These data suggest that cleaned gravels from
adjacent floodplain materials, used to enhance salmonid spawning sites, are quickly incorporated into the stream
ecosystem, benefiting benthic macroinvertebrate densities and dry biomass.
Nakano, S., and M. Murakami. 2001.
Reciprical Subsidies: Dynamic Interdependence Between Terrestrial and Aquatic Food Webs.
Proceedings of the National Academy of Sciences 98: 166–170.
Keywords: Trophic interactions between macroinvertebrates and fish
Abstract: Mutual trophic interactions between contiguous habitats have remained poorly understood despite their
potential significance for community maintenance in ecological landscapes. In a deciduous forest and stream
ecotone, aquatic insect emergence peaked around spring, when terrestrial invertebrate biomass was low. In
contrast, terrestrial invertebrate input to the stream occurred primarily during summer, when aquatic invertebrate
biomass was nearly at its lowest. Such reciprocal, across-habitat prey flux alternately subsidized both forest birds
and stream fishes, accounting for 25.6% and 44.0% of the annual total energy budget of the bird and fish
assemblages, respectively. Seasonal contrasts between allochthonous prey supply and in situ prey biomass
determine the importance of reciprocal subsidies.
Nakano, S., H. Miyasaka, and N. Kuhara. 1999.
Terrestrial-aquatic Linkages: Riparian Arthropod Inputs Alter Trophic Cascades in a Stream Food Web.
Ecology 80 (7) (October): 2435.
Keywords: Trophic interactions between macroinvertebrates and fish
Abstract: Dynamics of headwater stream ecosystems are generally regarded as occurring at the interface of
aquatic and terrestrial ecosystems. Terrestrial arthropod inputs can provide an energy subsidy and increase the
abundance of predatory fish, and the ensuing effects potentially can cascade through the food web and ultimately
affect primary producers. Nevertheless, the community-based effects of such inputs on stream food web dynamics
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are still poorly understood. We present experimental evidence that terrestrial arthropod inputs have an indirect
but prominent effect on a stream benthic community by altering the intensity of fish predation in the food web.
Two key elements of the stream food web, terrestrial arthropod inputs and the presence of predatory fish, were
experimentally manipulated by using greenhouse-type covers and enclosures (or exclosures) in a forest stream
located in northern Japan. When terrestrial arthropod inputs to the stream were experimentally reduced, fish
predation pressure shifted dramatically from terrestrial to aquatic arthropods. The ensuing depletion of aquatic
arthropods resulted in a subsequent increase in periphyton biomass. This field experiment revealed that terrestrial
arthropod inputs were a primary factor controlling cascading trophic interactions among predatory fish,
herbivorous aquatic arthropods, and benthic periphyton. These results provide empirical support for the
perspective that transfers of energy and biomass from donor systems are frequently significant for the
maintenance of biotic communities in recipient systems.
Ott, D.S., and T.R. Maret. 2003.
Aquatic Assemblages and Their Relation to Temperature Variables of the Least-disturbed Streams in the
Salmon River Basin, Central Idaho, 2001.
Water-Resources Investigations Report. Boise, ID: U.S. Geological Survey and Idaho Department of
Environmental Quality.
Keywords: Benthic macroinvertebrates as indicators of fish habitat quality.
Abstract: In the late 1990s, Idaho’s established stream temperature criteria for the protection of coldwater biota
and salmonid spawning were considered inadequate because the criteria did not agree with observed biological
conditions in many instances and did not allow for variability in environmental condition or species diversity across
a broad area such as the entire State of Idaho. In 2001, benthic invertebrate and fish assemblages in 34 leastdisturbed streams in the Salmon River Basin, central Idaho, were evaluated in relation to stream temperature and
other environmental variables. The Salmon River Basin retains watersheds that are minimally affected by human
activities. These “natural” stream conditions provide a basis for deriving attainable stream temperatures that can
be used to set new, and revise existing, water-quality criteria for stream habitats affected by human activities.
During July through September 2001, data were collected to document the thermal regime of least-disturbed
streams, characterize the distribution of aquatic biota at streams representing a gradient of temperature, and
describe the relations between environmental variables and benthic invertebrate and fish assemblages. Nine
stream temperature metrics were compared with the U.S. Environmental Protection Agency’s criterion of 10 ° C
(degrees Celsius) for bull trout spawning and juvenile rearing. The maximum weekly-maximum temperature at all
33 sites where temperature data were available exceeded this criterion. The maximum daily-maximum
temperature (MDMT) at 30 of the sites exceeded the Idaho Department of Environmental Quality (IDEQ) criterion
of 13.0 ° C for the protection of salmonid spawning; and the maximum daily-average temperature at all 33 sites
exceeded the 9.0 ° C criterion for the protection of salmonid spawning. The thermal regime at most sites did not
exceed the IDEQ criteria for the protection of coldwater biota. Nine environmental variables—water-surface
gradient, discharge, wetted channel width, width:depth ratio, aspect, total seasonal thermal input, open canopy,
riparian canopy density, and elevation were selected for correlation with the nine stream temperature metrics.
Elevation showed the strongest inverse correlation with the stream temperature metrics. Two hundred and one
benthic invertebrate taxa from the 34 sampling sites were identified. The most abundant taxa were Baetis
tricaudatus, Oligochaeta, Tvetenia bavarica gr., Acari, Rhithrogena, Cinygmula, Heterlimnius, Micropsectra,
Eukiefferiella devonica gr., Drunella doddsi, and Cricotopus. Of the 201 benthic invertebrate taxa collected during
this study, 57 taxa (present at a minimum of 5 sampling sites) were significantly correlated with one or more of the
stream temperature metrics. Among the invertebrate taxa collected, 32 were identified as coldwater taxa. Of the
coldwater taxa collected, Zapada oregonensis gr. showed the strongest inverse correlation with the stream
temperature metrics and was collected at sites where maximum weekly-maximum temperature (based on date of
sample and 6 days prior) ranged from 11.3 ° to18.5 °C. Ten species of fish in the families Salmonidae, Cottidae, and
Cyprinidae were collected. Two species (bull trout and chinook salmon) listed as threatened under the U.S. Fish
and Wildlife Service Endangered Species Act were collected. Among all species, bull trout showed the strongest
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inverse correlation between relative fish abundance and stream temperature. Bull trout and juvenile bull trout
densities were inversely correlated with stream temperature. The probability of occurrence of juvenile bull trout
was significantly correlated with MDMT on the basis of results from a logistic regression model developed during
this study. However, this model differed from a similar model developed by the U.S. Forest Service on the basis of
regional data collected in the Pacific Northwest. The regression model based on data collected during this study
showed higher probabilities of occurrence of bull trout at colder stream temperatures (10° to 15° C) and lower
probabilities of occurrence at warmer stream temperatures (16 °to 21°C) than did the model based on regional
data. The model comparisons suggest that regional or local differences need to be considered when deriving
stream temperature criteria.
Ott, R.A., A.K. Ambourn, F. Keirn, and A.E. Arians. 2005.
Relevant Literature for an Evaluation of the Effectiveness of the Alaska Forest Resources and Practices
Act: An Annotated Bibliography.
Alaska Coastal Management Program, Department of Natural Resources.
Available at: http://forestry.alaska.gov/pdfs/05effmoncomplete.pdf
Keywords: Trophic interactions between macroinvertebrates and fish
Abstract: The intent of this annotated bibliography was to identify projects throughout Alaska that address the
effectiveness of the current Alaska Forest Resources and Practices Act (FRPA) in protecting fish habitat and water
quality. The Act requires protection of ten components:
A.) channel morphology,
B.) clean spawning gravels,
C.) food sources,
D.) large woody debris,
E.) nutrient cycling,
F.) stream bank stability,
G.) stream flow,
H.) sunlight,
I.) water quality,
J.) water temperature.
Very little research has been conducted specifically to evaluate the effectiveness of FRPA. Therefore, this review
takes a broader approach and identifies projects that contribute to knowledge of the ten fish habitat and water
quality components and the impact of forest management practices on these components. We expanded the
literature search beyond Alaskan projects to provide additional information contributing to a general
understanding of aquatic ecosystems and the impacts of forest management upon them.
Piccolo, J. J., and M. S. Wipfli. 2002.
Does Red Alder (Alnus rubra) in Upland Riparian Forests Elevate Macroinvertebrate and Detritus Export
from Headwater Streams to Downstream Habitats in Southeastern Alaska? Canadian
Journal of Fisheries and Aquatic Sciences 59 (3): 503–513.
Keywords: Trophic interactions between macroinvertebrates and fish
Abstract: We assessed the influence of riparian forest canopy type on macroinvertebrate and detritus export from
headwater streams to downstream habitats in the Tongass National Forest, southeastern Alaska. Twenty-four
fishless headwater streams were sampled monthly, from April to August 1998, across four riparian canopy types:
old growth, clearcut, young-growth alder, and young-growth conifer. Young-growth alder sites exported
significantly greater count (mean = 9.4 individuals·m–3 water, standard error (SE) = 3.7) and biomass (mean = 3.1
mg dry mass·m–3 water, SE = 1.2) densities of macroinvertebrates than did young-growth conifer sites (mean = 2.7
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individuals·m–3 water, SE = 0.4, and mean = 1.0 mg dry mass·m–3 water, SE = 0.2), enough prey to support up to
four times more fish biomass if downstream habitat is suitable. We detected no significant differences in
macroinvertebrate export between other canopy types or in detritus export among different canopy types.
Roughly 70% of the invertebrates were aquatic; the rest were terrestrial or could not be identified. Although we do
not recommend clearcutting as a means of generating red alder, maintaining an alder component in previously
harvested stands may offset other potentially negative effects of timber harvest (such as sedimentation and loss
of coarse woody debris) on downstream, salmonid-bearing food webs.
Power, M.E. 1990.
Effects of Fish in River Food Webs. Science 250 (4982): 811–814.
Keywords: Trophic interactions between macroinvertebrates and fish
Abstract: Experimental manipulations of fish in a Northern California river during summer base flow reveal that
they have large effects on predators, herbivores, and plants in river food webs. California roach and juvenile
steelhead consume predatory insects and fish fry, which feed on algivorous chironomid larvae. In the presence of
fish, filamentous green algae are reduced to low, prostrate webs, infested with chironomids. When the absence of
large fish releases smaller predators that suppress chironomids, algal biomass is higher, and tall upright algal turfs
become covered with diatoms and cyanobacteria. These manipulations provide evidence that the Hairston, Smith,
Slobodkin–Fretwell theory of trophic control, which predicts that plants will be alternately limited by resources or
herbivores in food webs with odd and even numbers of trophic levels, has application to river communities.
Raggon, M.F. 2010.
Seasonal Variability in Diet and Consumption by Cottid and Salmonid Fishes in Headwater Streams in
Western Oregon, USA.
Master of Science, Corvallis, OR: Oregon State University.
Keywords: Trophic interactions between macroinvertebrates and fish
Abstract: Coastal cutthroat trout (Oncorhynchus clarkii clarkii) and cottids (Cottus spp) commonly co-occur in
headwater streams in western Oregon. Little is known about the comparative trophic ecology of these species or
how they respond to seasonal scarcity of resources. In this study I evaluated the seasonal variability in diets and
consumption as it related to food limitation for coastal cutthroat trout and cottids. Over 340 individual diets were
quantified from seasonal samples collected in May, July and September of 2008. Diet overlap was relatively low
among seasons and species. Coastal cutthroat trout exhibited a more diverse diet in terms of taxonomic richness
of prey and consumed both aquatic and terrestrially-derived prey, whereas cottids appeared to specialize on
aquatic prey. Based on diet composition and amount consumed, all species appeared to be increasingly food
limited from July to September, relative to May. However when diet composition was integrated with a
bioenergetic model, coastal cutthroat trout were found to be substantially more food limited than cottids.
Differences in the cost of activity between these species may explain this result. Activity costs may be higher for
trout, which reside in the water column and rely on active swimming, versus cottids, which lack a swim bladder
and are more benthic oriented. Results of this work suggest that cottids are dietary specialists, feeding almost
exclusively on benthic prey, whereas coastal cutthroat trout utilize a much broader resource base. In spite of this,
bioenergetic models suggest cottids fare better during periods of resource scarcity in headwater streams. Overall,
this suggests it is important to look beyond simple indicators of individual performance, such as directly observed
consumption or growth. Intense food limitation, especially for coastal cutthroat trout, may have important
implications for individuals, populations and species interactions during low flow conditions in streams in western
Oregon.
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Rehn, A. C., P. R. Ode, and C. P. Hawkins. 2007.
Comparisons of targeted-riffle and reach-wide benthic macroinvertebrate samples: implications for data
sharing in stream-condition assessments.
J.N. Am.Benthol. Soc. 26(2): 332-348.
Keywords:
Abstract. Recent comparisons of benthic macroinvertebrate (BMI) sampling protocols have shown that samples
collected from different habitat types generally produce consistent stream classifications and assessments.
However, these comparisons usually have not included biological endpoints used by monitoring agencies, such as
multimetric indices (e.g., benthic index of biotic integrity [B-IBI]) or observed to-expected (O/E) indices of
taxonomic completeness, as target variables, and estimates of method precision are rarely provided. Targetedriffle (TR) and reach-wide (RW) benthic samples have been collected at thousands of sites across the western USA,
but little guidance is available for understanding: 1) the extent to which raw data sets can be combined in regional
or large-scale analyses, 2) the degree of precision afforded by each method, or 3) the efficacy of cross-application
of biological indicators derived from one sample type to the other. To address these issues, we used data from 193
sites in California where the Environmental Monitoring and Assessment Program (EMAP) collected the 2 samples
side by side. We also conducted a separate study wherein 3 replicates of each sample type were collected from 15
streams to estimate minimum detectable difference (MDD) as a measure of each method’s precision. Metrics
calculated from TR and RWsamples showed similar dose–response relationships to stressor gradients and similar
raw scoring ranges. Biological indices (B-IBI, O/E0, and O/E50) derived from RW samples were more precise than
those derived from TR samples, but precision differences were not substantial. On average pairwise differences in
any index between TR and RW sample types were much less than the MDD associated with either sampling
method. We observed a weak but consistent bias toward higher O/E50 scores from TR samples than from RW
samples at the highest elevations and in the largest watersheds. Broad-scale condition assessments were nearly
identical when B-IBI and O/E0 were used as endpoints, and assessments based on O/E50 were only slightly less
similar. Our analyses indicate that raw data sets and biological indicators derived from TR and RW samples may be
generally interchangeable when used in ambient biomonitoring programs.
Relyea, C.D. 2007.
Fine Inorganic Sediment Effects on Stream Macroinvertebrates. Ph.D. dissertation,
Pocatello, ID: Idaho State University.
Available through: http://gradworks.umi.com/32/87/3287845.html
Keywords: Benthic macroinvertebrates as indicators of fish habitat quality
Abstract: This research explores the relationship between stream macroinvertebrates and fine inorganic sediment
across several spatial scales: regional (several ecoregions), single ecoregion (several catchments), single
catchment, and microhabitat. Three studies examined the distribution patterns of stream macroinvertebrates with
respect to habitat changes from fine sediment, and two examined mechanisms behind individual macro
invertebrate response to fine sediment. Using large-scale ecoregional distribution patterns of aquatic
macroinvertebrate response to fine sediment, I developed a Fine Sediment Biotic Index (FSBI) for use in
biomonitoring protocols. The Fine Sediment Biotic Index uses aquatic macroinvertebrates that respond to the
specific impact of increased fine sediment as bioindicators of fine sediment impacts. The FSBI was independently
tested and verified on three northwestern catchments and detected macro invertebrate community shifts
specifically due to increases in fine sediment. I also determined which rapid field and laboratory methods were
most accurate in measuring fine sediment deposits. The FSBI performs best in mountainous ecoregions at baseflow
conditions. In the smaller spatial scale studies; leaf decomposition declined with increases in fine sediment and
macroinvertebrates showed localized declines with even slight increases in sediment. Functional feeding groups
shifted and the presence of more shredding taxa did not hasten leaf decomposition if fine sediment was present.
Organic matter processing also was slower in flow tanks with high quantities of fine sediment. The response to
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increases in fine sediment was species-specific and several mechanisms may operate within one species. However,
it appears that loss of refugia in the substrate is one of the most important mechanisms behind macroinvertebrate
intolerance to fine sediment. Competition for space and predation appear to be important at the microhabitat
scale. Body morphology also plays a role in integrating substrate and hydraulic factors which allow an organism to
be found in a certain location on a rock. This study suggests that there is a transition point where hydraulic factors
are less important than substrate to macroinvertebrate distributions. For Drunella grandis, metabolic demand
associated with differences in movement activity increased on finer substrate. Overall, the response to increases in
fine sediment is complex involving substrate size, hydrodynamic factors, and animal behavior and morphology.
Reynoldson, T.B., R.H. Norris, V.H. Resh, K.E. Day, and D.M. Rosenburg. 1997.
“The Reference Condition: a Comparison of Multimetric and Multivariate Approaches to Assess Waterquality Impairment Using Benthic Macroinvertebrates.”
Journal of the North American Benthological Society 16 (4): 833–852.
Keywords: Benthic macroinvertebrates as indicators of fish habitat quality
Abstract: Traditional methods of establishing control sites in field-oriented biomonitoring studies of water quality
are limited. The reference-condition approach offers a powerful alternative because sites serve as replicates rather
than the multiple collections within sites that are the replicates in traditional designs using inferential statistics.
With the reference-condition approach, an array of reference sites characterizes the biological condition of a
region; a test site is then compared to an appropriate subset of the reference sites, or to all the reference sites
with probability weightings. This paper compares the procedures for establishing reference conditions, and
assesses the strengths and deficiencies of multimetric ( as used in the USA) and multivariate methods (as used in
the UK, Canada, and Australia) for establishing water-quality status. A data set of environmental measurements
and macroinvertebrate collections from the Fraser River, British Columbia, was used in the comparison. Precision
and accuracy of the 2 multivariate methods tested (AUStralian RIVer Assessment Scheme: AusRivAS, BEnthic
Assessment of SedimenT: BEAST) were consistently higher than for the multimetric assessment. Classification by
ecoregion, stream order, and biotic group yielded precisions of 100%f or the AusRivAS,8 0-100%f or the BEAST, and
40-80%f or multimetrics; and accuracies of 100%,1 00%, and 38-88%, respectively. Multimetrics are attractive
because they produce a single score that is comparable to a target value and they include ecological information.
However, not all information collected is used, metrics are often redundant in a combination index, errors can be
com-pounded, and it is difficult to acquire current procedures. Multivariate methods are attractive because they
require no prior assumptions either in creating groups out of reference sites or in comparing test sites with
reference groups. However, potential users may be discouraged by the complexity of initial model construction.
The complementary emphases in the multivariate methods examined (presence/absence in AusRivAS cf.
abundance in BEAST) lead us to recommend that they be used together, and in conjunction with, multimetric
studies
Reynoldson, T.B., R.C. Bailey, K.E. Day, and R.H. Norris. 1995.
Biological Guidelines for Freshwater Sediment Based on BEnthic Assessment of SedimenT (the BEAST)
Using a Multivariate Approach for Predicting Biological State.
Australian Journal of Ecology 20: 198–219.
Keywords: Benthic macroinvertebrates as indicators of fish habitat quality
Abstract This paper describes the first results for an alternative approach to the development of sediment quality
criteria in the nearshore areas of the Laurentian Great Lakes. The approach is derived from methods developed in
the United Kingdom for establishing predictive relationships between macroinvertebrate fauna and the physicochemistry of riverine environments. The technique involves a multivariate statistical approach using (i) data on the
structure of benthic invertebrate communities, (ii) functional responses (survival, growth and reproduction) in four
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sediment toxicity tests (bioassays) with benthic invertebrates; and (iii) selected environmental variables at 96
reference (‘clean’) sites in the nearshore areas of all five Great Lakes (Lakes Superior, Huron, Erie, Ontario and
Michigan). Two pattern recognition techniques (using the computer software package PATN) are employed in the
analysis: cluster analysis and ordination. The ordination vector scores from the original axes of the pattern analysis
are correlated (using CORR in SAS) with environmental variables which are anticipated to be least affected by
anthropogenic activities (e. g. alkalinity, depth, silt, sodium etc.). Multiple discriminant analysis (MDA) is used to
relate the site groupings from the pattern analysis to the environmental variables and to generate a model that
can be used to predict community assemblages and functional responses at new sites with unknown but potential
contamination. The predicted community assemblages and functional responses are then compared with the
actual benthic communities and responses at a site, and the need for remedial action is determined.
The predictive capability of the discriminant model was confirmed by performing several validation runs on
subsets of the data. An example of the use of the model for sediment in Collingwood Bay (an area of concern
designated by the IJC in Georgian Bay, Lake Huron) is presented and the technique is shown to be more precise in
determining the need for remediation than the currently used provincial sediment quality criteria based on
Screening Level Concentration (SLC) and laboratory toxicity tests. The ultimate goal of the study is the
development of a method to determine the need for, and the success of, remedial action and to predict what
benthic communities should look like at a site if it were clean and what responses of organisms in sediment toxicity
tests constitute an acceptable end-point.
Scheer, M. A. 2010.
Evaluating benthic macroinvertebrates as bio-indicators of freshwater habitat quality in an eastern
Oregon agro-ecosystem.
Thesis, Oregon State University. http://hdl.handle.net/1957/16303
Keywords:
Abstract: The effect of anthropogenic disturbance on river systems is gaining attention, and concerns about the
state of freshwater natural resources are increasing globally, as are efforts to restore habitat that has been
degraded by disturbance. In rivers, non-point source pollution affects the physical characteristics of the habitat
and the endemic biotic assemblages. Aquatic macroinvertebrates are numerous and exhibit graded responses to
various types of disturbance in the river, and may be used as indicators of habitat conditions. In this dissertation,
macroinvertebrates were examined as bioindicators in the Umatilla River in eastern Oregon. The first study is a
bioassessment of the impacts of agriculture on the benthic macroinvertebrate community in adjacent streams. The
results of this study show that there are physical differences in habitat associated with adjacent land use, and the
macroinvertebrate communities responded to these differences with changes in taxa richness and evenness.
Indicator species analysis identified thirteen taxa which were indicative of habitat conditions associated with ideal
habitat used as a reference condition, degraded habitat associated with agricultural land use, and transitional
habitat associated with conservation/restoration management. The second study is a laboratory study in which the
effects of temperature of a common mayfly nymph, Epeorus albertae (McDunnough) (Ephemeroptera:
Heptageniidae) were evaluated. The study showed that not only the developmental rate of the nymphs was
affected by temperature treatment (within a range of 18°C and 28°C), but the location of accumulated body tissues
over time varied by temperature, with significant difference in the type of growth observed for insects held at the
highest temperature. The third study examined the response of six indicator taxa to environmental variables as
predictors of abundance in a non-parametric multiplicative regression. This study found that for all taxa examined,
the two best predictors of abundance in the Umatilla River were turbidity and conductivity. Increased turbidity and
conductivity are common effects of intensive agriculture in streams located in agro-ecosystems, but may
potentially be mitigated by vegetative buffer strips and sustainable land use practices. Long term agricultural
disturbance in the landscape has been shown to have lasting effects in the ecosystem which may be further
exacerbated as global climate change increases dependence on freshwater resources. Understanding
anthropogenic impacts on organismal communities and natural resources is vital to establishment of effective
conservation, restoration, and maintenance of a healthy ecosystem.
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Southerland, M.T., G.M. Rogers, M.J. Kline, R.P. Morgon, R.P. Boward, P.F.
Kazyak, R.J. Klaudia, and S.A. Stranko. 2007.
Improving Biological Indicators to Better Assess the Conditions of Streams.
Ecological Indicators 7: 751–767.
Keywords: Benthic macroinvertebrates as indicators of fish habitat quality
Abstract: Biological indicators of stream condition are in use by water resource managers worldwide. The State of
Maryland and many other organizations that use Indices of Biotic Integrity (IBIs) must determine when and how to
refine their IBIs so that better stream condition information is provided. With completion of the second statewide
round in 2004, the Maryland Biological Stream Survey (MBSS) had collected data from 2500 stream sites, more
than doubling the number of sites that were available for the original IBI development. This larger dataset
provided an opportunity for the MBSS to address the following shortcomings in the original IBIs: (1) substantial
disturbance apparent in some reference sites, (2) fish IBIs could not be applied to very small streams, (3) natural
variability within IBIs (based on regions) resulted in some stream types (e.g., coldwater and blackwater streams)
receiving lower IBI scores and (4) one IBI was not able to discriminate degradation as desired (i.e., Coastal
Plain fish IBI). Therefore, development of new fish and benthic macroinvertebrate IBIs was undertaken to achieve
the goals of: (1) increased confidence that the reference conditions are minimally disturbed, (2) including more
natural variation (such as stream size) across the geographic regions and stream types of Maryland and (3)
increased sensitivity of IBIs by using more classes (strata) and different metric combinations. New fish IBIs were
developed for four geographical and stream type strata: Coastal Plain, Eastern Piedmont, warmwater Highlands
and coldwater Highlands streams; new benthic macroinvertebrate IBIs were developed for three geographical
strata: Coastal Plain, Eastern Piedmont and Highlands streams. The addition of one new fish IBI and one new
benthic macroinvertebrate IBI partitioned natural variability into more homogeneous strata. At the same time,
smaller streams (i.e., those draining catchments <300 ac), which constituted a greater proportion of streams (25%)
sampled in Round Two (2000–2004) than Round One (1995–1997), because of the finer map scale, were included
in the reference conditions used to develop the new IBIs. The resulting new IBIs have high classification efficiencies
of 83–96%and are well balanced between Type I and Type II errors. By scoring coldwater streams, smaller streams
and to some extent blackwater streams higher, the new IBIs improve on the original IBIs. Overall, the new IBIs
provide better assessments of stream condition to support sound management decisions, without requiring
substantial changes by cooperating stream assessment programs.
Stone, M. K, and J. B. Wallace. 1998.
Long‐term Recovery of a Mountain Stream from Clear‐cut Logging: The Effects of Forest Succession on
Benthic Invertebrate Community Structure.
Freshwater Biology 39 (1) (February 1): 151–169. doi:10.1046/j.1365-2427.1998.00272.x.
Keywords: Benthic macroinvertebrates as indicators of fish habitat quality
Abstract: 1. Changes in benthic invertebrate community structure following 16 years of forest succession after
logging were examined by estimating benthic invertebrate abundance, biomass and secondary production in
streams draining a forested reference and a recovering clear-cut catchment. Benthic invertebrate abundance was
three times higher, and invertebrate biomass and production were two times higher in the disturbed stream. 2.
Comparison of invertebrate community abundance 1, 5 and 16 years after clearcutting indicated that the
proportion of scrapers had decreased, whereas shredders had increased. Functional group percentage similarity
indicated that the invertebrate community in the disturbed stream 16 years after clear-cutting was more similar to
the reference than to that found earlier in the disturbed stream. 3. The five indices calculated from data collected
over the past 16 years, as well as the abundance, biomass and production data collected during this study, proved
to be of differing value in assessing recovery of the disturbed stream from logging. Percent dominant-taxon and
EPT (Ephemeroptera, Plecoptera and Trichoptera) taxon richness failed to show any initial differences between
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reference and disturbed streams, indicating that these indices may not be useful for measuring recovery from
logging. The percentage Baetis and shredder-scraper indices showed significant differences only during the 1977
study and suggest recovery (no difference between reference and disturbed) by 1982. The North Carolina Biotic
Index showed continued differences during 1982 in the riffle and depositional habitats and recovery by 1993. Total
macroinvertebrate abundance, biomass and production, as well as EPT abundance, indicated continued
differences between the reference and disturbed streams in the 1993 study.
Urabe, Hirokazu, Miyuki Nakajima, Mitsuru Torao, and Tomoya Aoyama. 2010.
Evaluation of Habitat Quality for Stream Salmonids Based on a Bioenergetics Model.
Transactions of the American Fisheries Society 139 (6) (November): 1665–1676. doi:10.1577/T09-210.1.
Keywords: Trophic interactions between macroinvertebrates and fish
Abstract: We examined the effectiveness of energetic potential (net energy intake [NEI]) estimated from
bioenergetics models as an index of habitat quality for stream salmonids in seven streams within four
watersheds in Hokkaido, northern Japan. In addition, we confirmed the utility of the NEI as an index of
habitat quality by comparing it with several other habitat variables, including pool volume, pool area ratio,
and prey density, that are often used as indices of habitat quality for stream salmonids. The mean NEI at each
study reach was closely related to salmonid abundance, although the physical environment and drifting prey
density differed considerably among study sites. In contrast, the relationships between habitat variables and
fish abundance were weaker (drift density) or nonsignificant (pool volume and area). These results suggest
that the NEI is more widely applicable as an index of habitat quality for drift-feeding fish, although its validity
should be tested in additional systems.
Weber, N. P., 2009
Evaluation of Macroinvertebrates as a Food Resource in the Assessment of Lotic Salmonid Habitat.
Thesis Utah State University.
http://digitalcommons.usu.edu/etd/286
Keywords:
Abstract: Criteria used to characterize lotic salmonid habitat are often based on observed correlations between
physical habitat characteristics and salmonid abundances. A focus on physical habitat features ignores other
habitat components, such as an adequate supply of food that set the physiological limitations on salmonid growth
and survival. This study outlines the development of a habitat assessment approach that focuses on how
invertebrate food availability interacts with stream temperatures to determine salmonid growth potentials.
Abundances of benthic and drifting invertebrate communities, stream temperatures, and juvenile steelhead trout
(Onchorhynchus mykiss gairdneri) summer growth rates and abundances were measured within 10 distinct stream
segments in central Oregon. Stream temperatures and growth rates were used as inputs for bioenergetics model
simulations to produce estimates of O. mykiss summer consumption rates. Measures of invertebrates providing
the best description of food availability were chosen based on their ability to explain observed variation in
salmonid consumption. Much of the variation in O. mykiss consumption estimates was explained by
measurements of total drift biomass along a type II predator response curve. A random effects analysis of variance
(ANOVA) was used to partition variation in invertebrate abundances across spatial and temporal scales.
Quantification of variation at multiple scales allowed identification of a relevant spatial scale at which to assess
macroinvertebrates relevant to salmonid populations, and compare the precision associated with measures of
benthic and drifting invertebrate abundances. Results suggested that spatial variation in drifting and benthic
invertebrate abundances are greatest at the scale of streams. Total drift biomass and total benthic biomass were
more precise at the stream and stream reach scale than drift and benthic density. The information provided by this
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study will be used to guide the development of sampling approaches that describe invertebrates in a manner more
directly related to salmonid production.
Weber, N.P. 2009.
Evaluation of Macroinvertebrates as a Food Resource in the Assessment of Lotic Salmonid Habitat.
Master’s Thesis, Logan, Utah: Utah State University.
Keywords: Trophic interactions between macroinvertebrates and fish
Abstract: Criteria used to characterize lotic salmonid habitat are often based on observed correlations between
physical habitat characteristics and salmonid abundances. A focus on physical habitat features ignores other
habitat components, such as an adequate supply of food that set the physiological limitations on salmonid growth
and survival. This study outlines the development of a habitat assessment approach that focuses on how
invertebrate food availability interacts with stream temperatures to determine salmonid growth potentials.
Abundances of benthic and drifting invertebrate communities, stream temperatures, and juvenile steelhead trout
(Onchorhynchus mykiss gairdneri) summer growth rates and abundances were measured within 10 distinct stream
segments in central Oregon. Stream temperatures and growth rates were used as inputs for bioenergetics model
simulations to produce estimates of O. mykiss summer consumption rates. Measures of invertebrates providing
the best description of food availability were chosen based on their ability to explain observed variation in
salmonid consumption. Much of the variation in O. mykiss consumption estimates was explained by
measurements of total drift biomass along a type II predator response curve. A random effects analysis of variance
(ANOVA) was used to partition variation in invertebrate abundances across spatial and temporal scales.
Quantification of variation at multiple scales allowed identification of a relevant spatial scale at which to assess
macroinvertebrates relevant to salmonid populations, and compare the precision associated with measures of
benthic and drifting invertebrate abundances. Results suggested that spatial variation in drifting and benthic
invertebrate abundances are greatest at the scale of streams. Total drift biomass and total benthic biomass were
more precise at the stream and stream reach scale than drift and benthic density. The information provided by this
study will be used to guide the development of sampling approaches that describe invertebrates in a manner more
directly related to salmonid production.
Wipfli, M. S, and D. P Gregovich. 2002.
Export of Invertebrates and Detritus from Fishless Headwater Streams in Southeastern Alaska:
Implications for Downstream Salmonid Production.
Freshwater Biology 47 (5): 957–969.
Keywords: Trophic interactions between macroinvertebrates and fish
Abstract: 1. We examined the export of invertebrates (aquatic and terrestrial) and coarse organic detritus from
forested headwaters to aquatic habitats downstream in the coastal mountains of southeast Alaska, U.S.A. Fiftytwo small streams (mean discharge range: 1.2–3.6 L s-1), representing a geographic range throughout southeast
Alaska, were sampled with 250-lm nets either seasonally (April, July, September) or every 2 weeks throughout the
year. Samples were used to assess the potential subsidy of energy from fishless headwaters to downstream
systems containing fish. 2. Invertebrates of aquatic and terrestrial origin were both captured, with aquatic taxa
making up 65–92% of the total. Baetidae, Chironomidae and Ostracoda were most numerous of the aquatic taxa
(34, 16 and 8%, respectively), although Coleoptera (mostly Amphizoidae) contributed the greatest biomass (30%).
Mites (Acarina) were the most numerous terrestrial taxon, while terrestrial Coleoptera accounted for most of the
terrestrial invertebrate biomass. 3. Invertebrates and detritus were exported from headwaters throughout the
year, averaging 163 mg invertebrate dry mass stream-1 day-1 and 10.4 g detritus stream1 day-1, respectively. The
amount of export was highly variable among streams and seasons (5–6000 individuals stream-1 day-1 and <1–22
individuals m)3 water; <1–286 g detritus stream)1 day)-1 and <0.1–1.7 g detritus m-3 water). Delivery of
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invertebrates from headwaters to habitats with fish was estimated at 0.44 g dry mass m-2 year-1. We estimate
that every kilometre of salmonid-bearing stream could receive enough energy (prey and detritus) from fishless
headwaters to support 100–2000 young-of-the-year (YOY) salmonids. These results illustrate that headwaters are
source areas of aquatic and terrestrial invertebrates and detritus, linking upland ecosystems with habitats lower in
the catchment.
Wipfli, M. S, and J. Musslewhite. 2004.
Density of Red Alder (Alnus rubra) in Headwaters Influences Invertebrate and Detritus Subsidies to
Downstream Fish Habitats in Alaska.
Hydrobiologia 520 (1): 153–163.
Keywords: Trophic interactions between macroinvertebrates and fish
Abstract: We investigated the influence of red alder (Alnus rubra) stand density in upland, riparian forests on
invertebrate and detritus transport from fishless headwater streams to downstream, salmonid habitats in
southeastern Alaska. Red alder commonly regenerates after soil disturbance (such as from natural land sliding or
timber harvesting), and is common along streams in varying densities, but its effect on food delivery from
headwater channels to downstream salmonid habitats is not clear. Fluvial transport of invertebrates and detritus
was measured at 13 sites in spring, summer and fall during two years (2000–2001). The 13 streams encompassed a
riparian red alder density gradient (1–82% canopy cover or 0–53% basal area) growing amongst young-growth
conifer (45-yr-old stands that regenerated after forest clearcutting). Sites with more riparian red alder exported
significantly more invertebrates than did sites with little alder (mean range across 1–82% alder gradient was about
1–4 invertebrates m−3 water, and 0.1–1 mg invertebrates m−3 water, respectively). Three-quarters of the
invertebrates were of aquatic origin; the remainder was of terrestrial origin. Aquatic taxa were positively related to
the alder density gradient, while terrestrially-derived taxa were not. Streams with more riparian alder also
exported significantly more detritus than streams with less alder (mean range across 1–82% alder gradient was
0.01–0.06 g detritus m−3 water). Based on these data, we predict that headwater streams with more riparian alder
will provide more invertebrates and support more downstream fish biomass than those basins with little or no
riparian alder, provided these downstream food
webs fully utilize this resource subsidy.
Wipfli, M.S., and C.V. Baxter. 2010.
Linking Ecosystems, Food Webs, and Fish Production: Subsidies in Salmonid Watersheds.
Fisheries 35 (8): 373–387.
Keywords: Trophic interactions between macroinvertebrates and fish
Abstract: Physical characteristics of riverine habitats, such as large wood abundance, pool geometry and
abundance, riparian vegetation cover, and surface flow conditions, have traditionally been thought to constrain
fish production in these ecosystems. Conversely, the role of food resources (quantity and quality) in controlling fish
production has received far less attention and consideration, though they can also be key productivity drivers.
Traditional freshwater food web illustrations have typically conveyed the notion that most fish food is produced
within the local aquatic habitat itself, but the concepts and model we synthesize in this article show that most fish
food comes from external or very distant sources—including subsidies from marine systems borne from adult
returns of anadromous fishes, from fishless headwater tributaries that transport prey to downstream fish, and
from adjacent streamside vegetation and associated habitats. The model we propose further illustrates how key
trophic pathways and food sources vary through time and space throughout watersheds. Insights into how food
supplies affect fishes can help guide how we view riverine ecosystems, their structure and function, their
interactions with marine and terrestrial systems, and how we manage natural resources, including fish, riparian
habitats, and forests.
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Wiseman, C.D., M. LeMoine, R. Plotnikoff, J. Diamond, A. Stewart, and S.
Cormier. 2010.
Identification of Most Probable Stressors to Aquatic Life in the Touchet River,
Washington. U.S. Environmental Protection Agency, National Center for Environmental Assessment,
Cincinnati, OH. EPA/600/R-08/145.
Keywords:
Abstract: The Washington State Department of Ecology (WSDE) currently practices “single-entry” total maximum
daily load (TMDL) studies. A single-entry TMDL addresses multiple water quality impairments concurrently, which
can reduce sampling costs, organize sampling group efforts, and provide an objective framework for basing
management decisions in the regulatory process. The Touchet River, a subwatershed of the Walla Walla River in
eastern Washington State, was listed for fecal coliform bacteria, temperature, and pH water quality impairments
and slated for a single-entry TMDL. The U.S. Environmental Protection Agency (U.S. EPA)’s Stressor Identification
procedures were used to identify and prioritize factors causing biological impairment and to develop effective
restoration plans for this river. Six sites were sampled along the Touchet River over a two-year period; parameters
measured included WSDE benthic macroinvertebrate assemblage metrics and physical habitat measures; chemical
analysis of pesticides and other pollutants; and in-situ temperature and pH measurements. Nearly every measure
of biological condition declined from upstream sites to downstream sites. A conceptual diagram was constructed
to identify potential sources of stressors, pathways, stressors, and biological measures of effect.
Seven candidate causes of biological impairment were considered: toxics, low dissolved oxygen (DO),
alkaline pH, water temperature, sedimentation, reduced detritus, and reduced habitat complexity. Toxic chemicals
measured did not exceed aquatic life criteria, and the low levels of pesticides were not considered a stressor by
toxicologists. Dissolved oxygen data rarely exceeded aquatic life criteria and were judged unlikely to cause the
observed effects. The remaining candidate causes were evaluated based on multiple types of evidence from the
case (spatial/temporal co-occurrence, stressor-response relationships from the field, and causal pathways) and
from elsewhere (stressor-response from other field studies, mechanistically plausible cause) and consistency of
evidence and consistency with other assessments. Evidence was qualitatively scored and the body of evidence was
weighed based on consistency of the evidence and best professional judgment of the ecology of the region.
Evidence corroborated temperature and sedimentation as highly probable causes of biological impairment.
Alkaline pH was also implicated for some areas but was judged to be less severe than temperature and sediment.
Reduced habitat complexity and cover were not directly causal, but could lead to sedimentation and warmer
water.
This screening causal assessment of the Touchet River, a subwatershed of the Walla Walla River in eastern
Washington State, is the first application of the United States Environmental Protection Agency (U.S. EPA) Stressor
Identification (SI) process to a long stretch of river or to the Northwest. To do this, several physiographically
matched reference sites were used for comparisons and evaluation of natural and cumulative stressor gradients. It
is also the first U.S. EPA report of a case using the SI method in an arid system or for endangered salmonids. Thus,
this case illustrates the range of applicability of the U.S. EPA methodology. The assessment identified probable
causes of impairments to macroinvertebrates and by association, certain salmonids.
Woodward, G. and A. G Hildrew. 2002.
Food Web Structure in Riverine Landscapes.
Freshwater Biology 47 (4) (April): 777–798. doi:10.1046/j.1365-2427.2002.00908.x.
Keywords: Trophic interactions between macroinvertebrates and fish
Abstract: 1. Most research on freshwater (and other) food webs has focused on apparently discrete communities,
in well-defined habitats at small spatial and temporal scales, whereas in reality food webs are embedded in
complex landscapes, such as river corridors. Food web linkages across such landscapes may be crucial for
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ecological pattern and process, however. Here, we consider the importance of large scale influences upon lotic
food webs across the three spatial dimensions and through time. 2. We assess the roles of biotic factors (e.g.
predation, competition) and physical habitat features (e.g. geology, land-use, habitat fragmentation) in moulding
food web structure at the landscape scale. As examples, external subsidies to lotic communities of nutrients,
detritus and prey vary along the river corridor, and food web links are made and broken across the land–water
interface with the rise and fall of the flood. 3. We identify several avenues of potentially fruitful research,
particularly the need to quantify energy flow and population dynamics. Stoichiometric analysis of changes in C : N :
P nutrient ratios over large spatial gradients (e.g. from river source to mouth, in forested versus agricultural
catchments), offers a novel method of uniting energy flow and population dynamics to provide a more holistic
view of riverine food webs from a landscape perspective. Macroecological approaches can be used to examine
large-scale patterns in riverine food webs (e.g. trophic rank and species–area relationships). New multivariate
statistical techniques can be used to examine community responses to environmental gradients and to assign traits
to individual species (e.g. body-size, functional feeding group), to unravel the organisation and trophic structure of
riverine food webs.
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