Inter-annual patterns in macroinvertebrate communities of wilderness streams in Idaho, U.S.A.

This study examined the inter-annual variation in macroinvertebrate assemblages in six wilderness streams in central Idaho over a 6-year period (1990–1995). Benthic macroinvertebrates and associated environmental correlates were sampled during baseflow each summer. Little environmental change, as assessed using coefficients of variation (CVs) for substrate size and embeddedness, width, depth and periphyton standing crops, occurred in the streams over the period of study. There was also little temporal change in macroinvertebrate assemblages based on the relative abundance of the 10 most abundant taxa, all shredder taxa and all plecopteran taxa. CVs for individual taxa were substantially greater than those of most community measures, with rare taxa contributing 30–50% of the variation for any one stream. Frequency distributions for taxa CVs excluding rare taxa were more normally distributed. Differences in assemblage structure among streams were attributed to stream size (shift in shredder assemblages) and temperature (shift in plecopteran taxa). These data indicate a long-term (multi-year) persistence in the macroinvertebrate composition of these pristine streams, thus supporting the premise that such streams are excellent references for use in long-term biomonitoring programs.     

Effects of local and regional factors on the fish assemblage structure in Meridional Amazonian streams

The aim of this study was to evaluate the effects of local, regional and temporal factors structuring fish assemblages in Meridional Amazonian streams during the months of May (rainy season) and August (dry season) of 2008. To accomplish this task, 14 streams located in Serra do Expedito (Aripuanã River basin) were sampled along 30-m stretches. A total of 3,212 specimens distributed among five orders, 18 families, and 55 species were recorded. The fish assemblage structure in the streams presented variation among types of riparian vegetation (local factor) and watersheds (regional factor), but did not present variation between seasons (temporal factor) and stream order (regional factor). Larger streams with margins covered with pasture presented higher species richness and abundance than smaller streams with margins covered with forest.     

Scales of spatiotemporal variability in macroinvertebrate abundance and diversity in monsoonal streams: detecting environmental change

1. We quantified spatial and temporal variability in benthic macroinvertebrate species richness, diversity and abundance in six unpolluted streams in monsoonal Hong Kong at different scales using a nested sampling design. The spatial scales were regions, stream sites and stream sections within sites; temporal scales were years (1997–99), seasons (dry versus wet seasons) and days within seasons. 2. Spatiotemporal variability in total abundance and species richness was greater during the wet season, especially at small scales, and tended to obscure site‐ and region‐scale differences, which were more conspicuous during the dry season. Total abundance and richness were greater in the dry season, reflecting the effects of spate‐induced disturbance during the wet season. Species diversity showed little variation at the seasonal scale, but variability at the site scale was apparent during both seasons. 3. Despite marked variations in monsoonal rainfall, inter‐year differences in macroinvertebrate richness and abundance at the site scale during the wet season were minor. Inter‐year differences were only evident during the dry season when streams were at base flow and biotic interactions may structure assemblages. 4. Small‐scale patchiness within riffles was the dominant spatial scale of variation in macroinvertebrate richness, total abundance and densities of common species, although site or region was important for some species. The proportion of total variance contributed by small‐scale spatial variability increased during the dry season, whereas temporal variability associated with days was greater during the wet season. 5. The observed patterns of spatiotemporal variation have implications for detection of environmental change or biomonitoring using macroinvertebrate indicators in streams in monsoonal regions. Sampling should be confined to the dry season or, in cases where more resources are available, make use of data from both dry and wet seasons. Sampling in more than one dry season is required to avoid the potentially confounding effects of inter‐year variation, although variability at that scale was relatively small.     

Improving biological indicators to better assess the condition of streams

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.     

Leaf litter decomposition and macroinvertebrate communities in headwater streams draining pine and hardwood catchments

Benthic invertebrates, litter decomposition, andlitterbag invertebrates were examined in streamsdraining pine monoculture and undisturbed hardwoodcatchments at the Coweeta Hydrologic Laboratory in thesouthern Appalachian Mountains, USA. Bimonthlybenthic samples were collected from a stream draininga pine catchment at Coweeta during 1992, and comparedto previously collected (1989–1990) benthic data froma stream draining an adjacent hardwood catchment. Litter decomposition and litterbag invertebrates wereexamined by placing litterbags filled with pine ormaple litter in streams draining pine catchments andhardwood catchments during 1992–1993 and 1993–1994. Total benthic invertebrate abundance and biomass inthe pine stream was ca. 57% and 74% that of thehardwood stream, respectively. Shredder biomass wasalso lower in the pine stream but, as a result ofhigher Leuctra spp. abundance, shredderabundance was higher in the pine stream than thehardwood stream. Decomposition rates of both pine andred maple litter were significantly faster in pinestreams than adjacent hardwood streams (p<0.05). Total shredder abundance, biomass, and production weresimilar in maple bags from pine and hardwood streams. However, trichopteran shredder abundance and biomass,and production of some trichopteran taxa such asLepidostoma spp., were significantly higher in maplelitterbags from pine streams than hardwood streams(p<0.05). In contrast, plecopteran shredders(mainly Tallaperla sp.) were more important inmaple litterbags from hardwood streams. Shredderswere well represented in pine litterbags from pinestreams, but low shredder values were obtained frompine litterbags in hardwood streams. Resultssuggest conversion of hardwood forest to pinemonoculture influences taxonomic composition of streaminvertebrates and litter decomposition dynamics. Although the impact of this landscape-leveldisturbance on invertebrate shredder communitiesappeared somewhat subtle, significant differences indecomposition dynamics indicate vital ecosystem-levelprocesses are altered in streams draining pinecatchments.     

Temporal variability in fish assemblages from disturbed and undisturbed streams

Fish assemblages were sampled by electrofishingover a two- to ten-year period in undisturbedand anthropogenically disturbed South Carolinacoastal plain streams. Jaccard similarity,Bray–Curtis similarity, and Spearman rankcorrelations among samples collected from thesame sites over time were significantly greaterat undisturbed sites than at disturbed sites,suggesting greater fish assemblage persistenceand stability at the undisturbed sites. TheIndex of Biotic Integrity (IBI) also exhibitedsignificantly less variation over time atundisturbed sites than at disturbed sites.Physical habitat structure changed more overtime at disturbed sites than at undisturbedsites, and this variability was directlyrelated to temporal variability in fishassemblage structure. Comparisons betweenmultiple and single pass electrofishing samplessuggested that only a small proportion of thetemporal variability observed at the studysites was caused by inefficient sampling.Assessment of temporal variation in fishassemblage structure can serve as an indicatorof environmental disturbance and facilitate thedistinction of substantive ecological changefrom normal background variation.     

Effect of riparian land use on contributions of terrestrial invertebrates to streams

Since terrestrial invertebrates are often consumed by stream fishes, land-use practices that influence the input of terrestrial invertebrates to streams are predicted to have consequences for fish production. We studied the effect of riparian land-use regime on terrestrial invertebrate inputs by estimating the biomass, abundance and taxonomic richness of terrestrial invertebrate drift from 15 streams draining catchments with three different riparian land-use regimes and vegetation types: intensive grazing — exotic pasture grasses (4 streams), extensive grazing — native tussock grasses (6 streams), reserve — native forest (5 streams). Terrestrial invertebrate drift was sampled from replicated stream reaches enclosed by two 1 mm mesh drift nets that spanned the entire channel. The mean biomass of terrestrial invertebrates that entered tussock grassland (12 mg ash-free dry mass m^–2 d^–1) and forest streams (6 mg AFDM m^–2 d^–1) was not significantly different (p > 0.05). However, biomass estimated for tussock grassland and forest streams was significantly higher than biomass that entered pasture streams (1 mg AFDM m^–2 d^–1). Mean abundance and richness of drifting terrestrial invertebrates was not significantly different among land-use types. Winged insects contributed more biomass than wingless invertebrates to both pasture and tussock grassland streams. Winged and wingless invertebrates contributed equally to biomass entering forest streams. Land use was a useful variable explaining landscape-level patterns of terrestrial invertebrate input for New Zealand streams. Evidence from this study suggests that riparian land-use regime will have important influences on the availability of terrestrial invertebrates to stream fishes.     

Fishes of Indiana streams: current and historic assemblage structure

We examined Indiana fish assemblages using taxonomy and ecological categories to assess temporal shifts in community structure and recent environmental relationships. Historic (1945) and recent (1996–2007) presence/absence data were compiled by subbasin and analyzed with Nonmetric Multidimensional Scaling (NMS) ordination and by species richness. Canonical Correspondence Analysis (CCA) was used to test taxonomic identity and ecological category abundance data for explanation with recent (1996–2007) environmental variables. We found a decrease in assemblage heterogeneity for recent assemblages and an increase in the number of tolerant species per subbasin. Recent Indiana streams are dominated by tolerant fishes with generalist life history strategies and low functional variation. The use of ecological categories resulted in weaker relationships with environmental variables than analyses with taxonomic identities. Analyses using taxonomy resulted in strong assemblage explanation from stream size and flow variation, while analyses using ecological categories resulted in strong assemblage explanation from habitat variation in silt substrates and flow. Analyses of recent assemblage structure using ecological categories resulted in decreased assemblage variation among subbasins than in analyses using taxonomic identities. We found that fish assemblages of Indiana streams are structured primarily by habitat complexity and have been altered during the past 50 years through multiple disturbances including fragmentation, siltation, and species introductions.     

Quantifying the direct and indirect effects of flow‐related disturbance on stream fish assemblages

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Assessment of an index of biological integrity (IBI) to quantify the quality of two tributaries of river Chenab,Sialkot, Pakistan

Nullah Aik and Nullah Palkhu, two tributaries of river Chenab, were investigated for the assessment of fish habitat degradation as indicator of stream health. Fish abundance data were collected from 18 sites from September 2004 to April 2006 to develop multimetric indices for fish assemblage integrity and to detect the intensity of habitat degradation. A total of 12 metrics were calculated on the basis of taxonomic richness, habitat preference, trophic guild, stress tolerance and origin of species to develop stepped and continuous index of biological integrity (IBI) criteria. Cluster analysis (CA) classified sites based on species composition into three groups, viz., reference, moderately impaired and impaired groups. Non-metric multidimensional scaling (NMDS) was applied to identify underlying ecological gradient to highlight the habitat degradation. NMDS segregated two sites as less impaired, five sites as moderately impaired and eleven sites as impaired groups. Axes 1 and 2 explained a total variation of 53.3%. First axis explained the level of habitat impairment, whereas axis 2 indicated species richness along longitudinal gradient of streams. Sites located upstream of Nullah Aik showed higher IBI scores which dropped to its lowest in downstream sites near Sialkot city. Lowest values of IBI of sites in close proximity of city indicated the role of anthropogenic activities in catchment areas. The results indicated that variability in water chemistry can be related as a function of stream sites impairments (i.e., unimpaired, moderately impaired, and severely impaired). Water quality parameters showed strong correlation with IBI scores. Significantly negative correlation of IBI scores with COD, TDS, turbidity, Fe, Cr, Zn and positive correlation with DO and pH was found. The results can be used for restoration and future management of small streams passing through urban areas of Pakistan. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users. Handling editor: J. A. Cambray     

A fish index of biotic integrity for South Dakota's Northern Glaciated Plains Ecoregion

Ecosystem goods and services in streams are impaired when their biotic communities are degraded by anthropogenic stressors. An index of biotic integrity (IBI) translates community structure into a standardized ecoregion-specific stream health score. Documenting stream health is especially important in the Northern Glaciated Plains (NGP) Ecoregion, which is undergoing rapid landscape alterations through increased agriculture production. Our objectives were to develop a fish IBI and validate candidate reference sites for NGP wadeable perennial streams. Fish were sampled from 54 sites (consisting of reference sites, known-condition least and most disturbed sites, and random sites) during summers 2006–2011. Candidate metrics were sorted into nine metric classes based on attributes of fish assemblage form and function. Metric values were screened using metric range, signal-to-noise ratios, responsiveness to disturbance, and redundancy tests until each metric class contained only those metrics most responsive to anthropogenic stressors. The final IBI consisted of six metrics that were reflective of prairie stream fish assemblages, and differentiated between known-condition least and most disturbed sites. The mean reference sampling site IBI scores were found to be similar to both least and most disturbed sites (Mann–Whitney U-test; P < 0.05). Twelve reference site scores were below the NGP's median (69), whereas the other 11 sites were above the median and were representative of least disturbed conditions. We now have developed a standardized bioassessment tool for evaluating stream health, as well as a baseline for long-term monitoring in a dynamic ecoregion.     

An index of biotic integrity based on fish assemblages for subtropical streams in southern Brazil

Several methods for calculating indices of biological integrity (IBIs) have been developed for different ecogeographic regions of the world. All of them calculate IBI scores by comparing against reference sites or historical data on fish assemblage composition. Because of intensive agriculture and urbanization in our study area, we located no reference sites, and historical information about fish assemblage composition did not exist. Instead, we developed hypothetical reference scores based on seasonal electrofishing surveys at six study sites in adjacent but geomorphologically different watersheds. Our IBI included 10 metrics that varied with degree of degradation. We found that Shannon–Wiener indices varied significantly between seasons, indicating significant changes in species composition. Therefore, we calculated seasonal IBI scores also, but these did not significantly differ from each streams general IBI score, which was calculated on the basis of four samples per site. General stream IBI scores reflected differing levels of anthropogenic disturbance.     

Beta diversity of aquatic macroinvertebrate assemblages associated with leaf patches in neotropical montane streams

Over 70% of the total channel length in all river basins is formed by low order streams, many of which originate on mountaintops. Headwater streams play fundamental roles in processing and transporting terrestrial and aquatic organic matter, often harboring high biodiversity in bottom leaf patches deposited from riparian vegetation. The objective of this study was to assess the variation in taxonomic composition (measured by beta diversity of aquatic macroinvertebrates) among stream sites located in the Espinhaço Meridional Mountain Range, part of a UNESCO Biosphere Reserve in eastern Brazil. We tested two hypotheses. (a) Taxa turnover is the main reason for differences in aquatic insect assemblages within stream sites; we predicted that turnover would be higher than nestedness in all stream sites. (b) Stream site altitude and catchment elevation range are the main explanatory variables for the differences in beta diversity; we predicted that local stream site variables would account for only minor amounts of variation. In both dry and wet seasons, we sampled twice in two habitat types (five leaf patches in pools and five in riffles) in each of nine stream sites distributed in three different river basins. We computed average pairwise beta diversity among sampling stations and seasons in each stream site by using Jaccard and Bray–Curtis indices, and calculated the percentages of diversity resulting from turnover and nestedness. Finally, we tested the degree that local‐ or catchment‐level predictor variables explained beta diversity. We found that turnover was the main component of beta diversity and that both dissolved oxygen and elevation range best explained Bray–Curtis beta diversity. These results reinforce the importance of leaf patches in montane (sky islands) Neotropical savanna streams as biodiversity hotbeds for macroinvertebrates, and that both local and landscape variables explained beta diversity.     

Temporally variable macroinvertebrate–stone relationships in streams

Stones were used to sample macroinvertebrates and characterise microhabitats at monthly or bimonthly intervals in six Ecuadorian streams covering a gradient in four different stability measures and other stream characteristics. The physical variables current velocity, water depth, horizontal position, embeddedness and size were measured to characterise stone microhabitats and presumed to be affected by or related to physical impact during hydrological disturbances. My first objective was to analyse how density, the number of families and a richness measure (residuals from a power regression of families vs. individuals) were related to the physical characteristics of individual stone habitats. My second objective was to quantify temporal variability in fauna–stone relationships and to analyse if such variability was related to overall stability of stream reaches. Partial Least Squares (PLS) multiple regression analyses showed high temporal variability between sampling dates in factor loadings of specific stone micro habitat variables. In spite of this, there was a clear negative effect of depth and a positive effect of current on density and number of families. Stone size was consistently negatively related to density and positively related to number of families. Patterns were less clear for richness residuals. Simple linear regressions of fauna vs. stone parameters generally confirmed the results reached by the PLS analysis, although few of the regressions were significant. For all fauna–stone regressions the variability in slopes was much higher among sampling dates within streams (temporal variability) than among streams (spatial variability), and significant slopes were even inverted on different sampling dates. Although the coefficients of variation (CV) of slopes of a given combination of fauna parameter and stone variable from different sampling dates (n=9–11) were rarely correlated to any of the measures of stream stability, this study has demonstrated high temporal variability in fauna–stone relationships (CV’s of regression slopes). Consequently, temporally un-replicated studies of such relationships do not necessarily reveal general patterns.     

Modification of an index of biotic integrity based on fish assemblages to characterize rivers of the Seine Basin,France

The Index of Biotic Integrity (IBI) is a measure of fish assemblage health that has been used to assess catchment and stream quality throughout North America. It reflects human perturbations on natural environmental structures and processes. While preserving the ecological foundation of the original North American metrics, we have modified and adapted the IBI to the mainstem Seine River and its major tributaries in France. This successful modification of the IBI to a considerably different fish fauna on a different continent further supports its wider use outside the midwestern United States. Using data collected in 1967, 1981, and 1988–1989 from a total of 46 sites, we show spatial and temporal variation in the Seine as indicated by IBI scores. Statistically significant relationships were found between IBI and catchment area but insignificant relationships existed between IBI and an independent Water Quality Index (WQI) based on water chemistry. Comparisons between the IBI and the WQI indicate that the former is a more sensitive and robust measure of water body quality. Our results demonstrate that the IBI, combined with a statistically designed national monitoring program, would offer a reliable means of assessing spatial patterns and temporal trends in water body improvement or degradation in France. The more primitive fish families in the Basin were affected first by perturbations. These families include all the diadromous species found in the Seine and suggest serious disruption of their life histories.     

Effects of pulsed and pressed disturbances on the benthic invertebrate community following a coal spill in a small stream in northeastern USA

In September 1999, a coal-carrying train derailed and spilled 180,000–270,000 kg of coal into the Cayuga Inlet near Ithaca, New York. This study determined the immediate effects of the coal spill and the clean up procedures on the aquatic invertebrate community, and whether the stream recovered from this event after 2 years. Benthic invertebrate samples were taken both upstream and downstream of the coal spill immediately following clean-up efforts and two years later. Just after the coal spill, the total abundance and species richness of aquatic invertebrates were significantly lower downstream of the spill, suggesting that the disturbance caused increased mortality and/or emigration compared to a reference site upstream. Taxa affected most were grazers and turbidity-susceptible invertebrates. Two years later the invertebrate communities were similar upstream and downstream of the spill, except for an increase in the percent of the dominant genus, Hydropsyche(Trichoptera: Hydropsychidae). We speculate that long-term effects of channelization of the stream that occurred during the clean-up prevented the invertebrate assemblage from returning to the conditions observed in a reference site upstream of the coal spill. We propose that large scale environmental clean-ups should be designed to avoid altering ecosystems permanently, and that streams should be allowed to recover naturally without destructive human intervention.     

Physico-chemistry and aquatic insects of a glacier-fed and a spring-fed alpine stream

1. Physico-chemical conditions and benthic macroinvertebrates were studied in two adjacent alpine streams in the Tyrolean Alps, Austria, for 2 years, and aquatic insect emergence was recorded for 1 year.
2. In the spring-fed system, maximum discharge and increased concentrations of suspended solids, nitrate and particulate phosphorus occurred during snowmelt in June. In the glacier-fed stream, high discharge and strong diel fluctuations in flow and concentrations of suspended solids created a harsh and unstable environment during summer. Glacial ablation, variation in groundwater inflow, and water inputs from tributaries draining calcareous rocks caused water chemistry to vary both seasonally and longitudinally in glacier-fed Rotmoosache.
3. A total of 126 aquatic or semi-aquatic invertebrate taxa were collected, 94 of which were found in the glacier-fed stream and 120 in the spring-fed stream. Chironomid abundance was 2–8 times and taxa richness 2–3 times lower in the glacier-fed stream than in the spring-fed stream, as was the number of chironomid taxa (72 versus 93 total).
4. These results broadly support the conceptual model by Milner & Petts (1994) concerning glacier-fed stream systems. However, single samples and seasonal means showed relatively high invertebrate abundance and richness, especially during winter, indicating a considerable degree of spatial and temporal variability.
5. We suggest that the seasonal shifts from harsh environmental conditions in summer to less severe conditions in autumn and a rather constant environment in winter are an important factor affecting larval development, life-history patterns and the maintenance of relatively high levels of diversity and productivity in glacier-fed streams.     

Influences of low-head dams on the fish assemblages in the headwater streams of the Qingyi watershed, China

The influences of low-head dams on the fish assemblages were examined in this study, using fish data collected in six treatment and five reference sites at three low-head dams in the headwater streams of the Qingyi watershed, China. Comparing with those in the reference sites, local habitat variables were significantly altered by low-head dams in the treatment sites, involving wider channel (only in the impoundment area), deeper water and slower flow. Fish species richness varied significantly across seasons, not across site categories, suggesting that these low-head dams did not alter species richness. However, significant decreases in fish abundance and density were observed in the impoundment areas immediately upstream of dams, but not in the plunge areas downstream. Fish assemblage structures kept relative stability across seasons, and their significant difference between-site was only observed between the impoundment areas and the sites far from dams upstream. This variation in assemblage structures was due to the differing relative abundance of some co-occurring species; more lentic but less lotic fish was observed in the impoundment areas. The spatial and temporal patterns of fish assemblages were correlated with local habitat in this study area. Wetted width had negative correlation with fish species richness, abundance and density, respectively. Water temperature also positively affected species richness. In addition, wetted width, water depth, current velocity and substrate were the important habitat variables influencing assemblage structures. Our results suggested that, by modifying local habitat characteristics, low-head dams altered fish abundance and density in the impoundment areas immediately upstream of dam, not in the plunge areas immediately downstream, and thereby influenced fish assemblage structures in these stream segments.     

Long-term recovery of a mountain stream from clear-cut logging: the effects of forest succession on benthic invertebrate community structure

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 clear-cutting 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 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.