Illinois Streams Research Articles

Movement behavior and passive dispersal of a reintroduced population of alligator snapping turtles

AbstractMaladaptive movement behavior is a leading cause of failure for reptile reintroductions, thus characterizing movement for translocated populations is important to project success. From 2014–2016 we radio‐tracked 183 immature reintroduced alligator snapping turtles (Macrochelys temminckii) using very high frequency telemetry in a stream in southern Illinois, USA. We assessed environmental, temporal, morphometric, and microhabitat factors influencing movement, including post‐release dispersal from reintroduction sites, movement probability, and step length. We used directional statistics to investigate the effects of precipitation and age on directional movement in the stream. Numerous factors influenced active movement, including ambient temperatures, time since release, use of log jams, turtle size, and age. Precipitation had an age‐biased effect on movement. Directional analyses suggested that movement was largely passive as turtles were swept downstream with increased discharge. Overall, the behavior of reintroduced alligator snapping turtles was similar to that reported in wild populations. Passive downstream transport has implications for reintroduced and natural populations as a force for unintentional emigration in channelized streams under current conditions and future high flow regimes.

Thermal tolerance of fish to heatwaves in agricultural streams: What does not kill you makes you stronger?

Abstract Heatwaves are increasing in frequency and intensity under climate change. Freshwater ecosystems are among the most thermally impacted systems, within which agricultural streams are experiencing the most extreme heatwaves and deserve prioritised focus. Heatwaves are approaching the upper thermal limits of many fishes but have received little attention to date. To study whether and how fish tolerate heatwaves from a physiological perspective, we simulated single, multiple, and extended heatwaves at 32 and 34°C in the laboratory, based on high‐resolution summer temperatures recorded in agricultural versus forested streams in Illinois, U.S.A. By investigating the effects of heatwaves on 25°C acclimated fathead minnow Pimephales promelas, an important prey species across North America, we witnessed its high thermal resilience, including a rapid return to metabolic homeostasis after single and multiple heatwaves, measured by oxygen consumption rate. During an extended heatwave, fathead minnow were still able to partially lower oxygen consumption rate after the initial exposure. We also found transient increases in their critical thermal maximum, especially after higher intensity and frequency of heatwaves. However, the thermal resilience of fathead minnow did come with costs, including reduced anaerobic capacity indicated by decreased lactate dehydrogenase activity and impaired antioxidant defence indicated by reduced superoxide dismutase in white muscle. By monitoring metabolic costs and physiological adjustments of fish during and after heatwaves, we showed that fathead minnow were resilient to simulated current and near‐future heatwaves, which may allow them to cope with thermal extremes expected in agricultural streams. Overall, the real‐time monitoring of fish responses to heatwaves incorporates natural dynamics of thermal patterns. It facilitates mechanistic understandings of how fish react to thermal challenges in the real world and offers opportunities to incorporate high‐resolution metabolic costs into future bioenergetic modelling.

Species richness of mussel assemblages and trait guilds in relation to environment and fish diversity in streams of Illinois, the USA

Species richness of mussel assemblages and trait guilds in relation to environment and fish diversity in streams of Illinois, the USA

How Surface Water Management Can Benefit Fish Conservation in Urban Streams

Abstract We analyzed 33 y of fish community data collected from a low-order, urban stream in central Illinois, USA, to determine the effects of municipal wastewater management projects and urbanization on fish communities. From 1985 to 2017, species richness, number of pollution-intolerant species, and alternative index of biotic integrity significantly increased at sites across this system. Species diversity likewise increased, but was mostly significant only at sites downstream of the effluent outflow. Ceasing the chlorination of wastewater in 1990 resulted in significant increases in fish community metrics both upstream and downstream of effluent outflow, although effects varied from site to site. Completing a combined sewer overflow abatement project in 2008 resulted in some significant increases in species richness, diversity, and number of pollution-intolerant species at sites downstream of effluent outflow. From 2001 to 2016, the change in the number of pollution-intolerant species correlated inversely with the increased percentage of impervious cover in the study system. There was no significant correlation of other metrics with the change in percent impervious surfaces. These results suggest that urbanization at upstream sites limited to some extent the benefits of water management interventions that improved fish community metrics at downstream sites.

The impact of channelization on macroinvertebrate bioindicators in small order Illinois streams: insights from long-term citizen science research

Channelization can have far-reaching and long-term impacts on stream ecology. In this study, we demonstrate that channelization is associated with lower stream quality as measured by macroinvertebrate bioindicators when compared to unchannelized streams. Citizen scientists collected the data for this study between 1995 and 2014, performing 3021 sampling events during the months of May and June across 567 Illinois streams. We found significantly lower taxa richness, EPT taxa richness, and macroinvertebrate biotic index values in channelized sites. Our findings also show prevalent siltation in channelized sites that is likely negatively affecting macroinvertebrates, along with a possible lower availability of quality habitat. We also measured stream velocity and found that average velocity did not differ between our channelized and unchannelized sites. Our findings suggest stream velocity was not a driving factor in determining the differences in macroinvertebrate assemblages, although we cannot comment on the possible change in velocity from pre to post channelization at each site. This study allows for a large dataset that covers diverse streams across the entire state of Illinois. Our work provides example and encouragement for other researchers to take advantage of the power of citizen science, and the existing large datasets available from these projects.

Predicting the range of a regionally threatened, benthic fish using species distribution models and field surveys.

Understanding a species' historical and current distribution is critical when making conservation and management decisions. Recent observations in headwater streams of northern Illinois, USA, where no previous records of Iowa Darters Etheostoma exile occurred, revealed the need to re-evaluate its state-wide distribution. We conducted a series of species distribution modelling procedures coupled with targeted field surveys to generate historical and contemporary distribution models. The historical distribution model indicated E. exile distributions were concentrated across extreme northern Illinois. Both contemporary models included results of the historical model as a model variable. Based on the initial contemporary model, 30 potential Iowa Darter sites, 10 each of three groups representing low, medium and high model scores, were sampled during the summer of 2016. Field surveys provided nine new E. exile localities and presence-absence data from field surveys were then applied to revise the contemporary model. The revised contemporary model suggests a decrease in certain areas of its historic Illinois range, as well as areas where it has potentially expanded its range.

Nitrous Oxide Fluxes from Agricultural Streams in East-Central Illinois

Indirect nitrous oxide (N2O) emissions account for the majority of uncertainty associated with the global N2O budget. Agricultural streams with subsurface (tile) drainage are potential hotspots of indirect N2O emissions from streams and groundwater. However, there are only a limited number of studies with direct measurements from stream surfaces. Research presented here represents the first study of N2O emissions from agricultural streams in Illinois, USA. We measured water chemistry data from 10 sites in three watersheds in east-central Illinois. Additionally, floating chambers and gas transfer velocity models were used to measure N2O fluxes from the stream surface at 4 of the 10 sites. Dissolved N2O concentrations ranged from < 0.1 to 7.46 μg N2O-N L−1. Floating chamber N2O fluxes ranged from 0 to 13.84 μg N2O-N m−2 min−1. We found strikingly different patterns of nitrate (NO3−) concentrations at sites downstream of a wastewater treatment plant (WWTP) effluent. Data from sites not affected by the WWTP expressed seasonal variations of NO3− with elevated concentrations in winter and spring months when subsurface tile drains were flowing. Floating chamber N2O fluxes were strongly correlated (p value 0.001) with NO3− at sites not affected by the WWTP. All sites were correlated with flow (p value 0.01) and dissolved N2O (p value 0.02). Our data suggest flow and dissolved N2O are stronger indicators of N2O flux from stream surfaces than NO3− concentrations in agricultural watersheds. Furthermore, this study supports growing concerns of estimating N2O emissions using linear relationships between N2O and NO3−, such as those used in IPCC estimates.

Some Phoretic Associations of Macroinvertebrates on Transplanted Federally Endangered Freshwater Mussels

Abstract Benthic macroinvertebrates were washed from nearly 1000 federally endangered freshwater mussels that had been collected from Pennsylvania during a reintroduction project to 2 eastern Illinois streams. Most benthic macroinvertebrates collected were larvae of the Neophylax fuscus, but other caddisflies and segmented worms were also observed. No unoccupied caddisfly cases were observed on live mussels, leaving open the question as to the seasonal fate of these microhabitats after caddisflies pupate and emerge in the Autumn of each year. Unionid mussel shells might modify local-scale species diversity by influencing physical and hydrau lic properties of microhabitats.

Reconstructing the natural distribution of individual unionid mussel species and species diversity in wadeable streams of Illinois, USA, with reference to stream bioassessment

AbstractFreshwater mussels are considered one of the most imperiled aquatic species groups in the USA. One of the challenges in protecting and restoring mussel biodiversity effectively is a lack of understanding of their natural distributions at relevant spatial scales. Without this information, assessing the current status of individual species and overall biodiversity or evaluating restoration success is difficult. We compiled records for 45 mussel species and a range of natural environmental variables describing climate, geology, soil, land cover, and watershed topography in Illinois wadeable streams. We used reaches (segments between 2 neighboring tributaries) as the basic spatial unit of the stream network for modeling species distributions with Maxent. We applied these models statewide to all identified wadeable reaches. Stacking the predictions of individual models yielded an estimate of species richness for each reach. The estimates were compared with observed richness from 2 sets of independent s...

Modeling and mapping fish abundance across wadeable streams of Illinois, USA, based on landscape-level environmental variables

To effectively conserve and restore stream ecosystems, we need to better understand the distribution and abundance of individual fish species in relation to natural environments and anthropological stressors. In this study, we modeled the abundance of 97 fish species in small wadeable streams of Illinois, USA, based on random forests regression and landscape-level environmental variables. Model R2 values for intermediately common species were higher than for common species, but highly variable among rare ones. Models for 50 species reached R2 of 0.2–0.70 and were tested with a separate set of samples and applied to unsampled wadeable reaches to show the population hotspots of each species across the state. Furthermore, we evaluated the importance of individual environmental variables to a given fish species as well as the directional responses of each species to top 10 key predictors. Climate and land use were the best predictors for most species, followed by topography, geology, and soil permeability. Spatial connection of a stream also was associated with a large number of species. These findings improved our understanding of the relationships between fish species and landscape environments. The distribution maps could guide resource management, restoration, and monitoring of stream fish assemblages.

Heat tracing to examine seasonal groundwater flow beneath a low-gradient stream in rural central Illinois, USA

The thermal profile of a streambed is affected by a number of factors including: temperatures of stream water and groundwater, hydraulic conductivity, thermal conductivity, heat capacity of the streambed, and the geometry of hyporheic flow paths. Changes in these parameters over time cause changes in thermal profiles. In this study, temperature data were collected at depths of 30, 60, 90 and 150 cm at six streambed wells 5 m apart along the thalweg of Little Kickapoo Creek, in rural central Illinois, USA. This is a third-order low-gradient baseflow-fed stream. A positive temperature gradient with inflection at 90-cm depth was observed during the summer period. A negative temperature gradient with inflection at 30 cm was observed during the winter period, which suggests greater influence of stream-water temperatures in the substrate during the summer. Thermal models of the streambed were built using VS2DHI to simulate the thermal profiles observed in the field. Comparison of the parameters along with analysis of temperature envelopes and Peclet numbers suggested greater upwelling and stability in temperatures during the winter than during the summer. Upwelling was more pronounced in the downstream reach of the pool in the riffle and pool sequence.

Modelling and mapping the distribution, diversity and abundance of freshwater mussels (Family Unionidae) in wadeable streams of Illinois, U.S.A.

Summary Freshwater mussels are one of the most imperilled animal groups in the world. Their effective conservation and restoration require a better understanding of their spatial distributions at a relevant scale and of their relationships with natural environmental factors and human disturbances. In this study, we sampled over 900 sites on wadeable streams throughout Illinois, U.S.A., and compiled environmental data for a wide range of natural and anthropogenic factors related to climate, geology, land use, and connections to large rivers, dams and ponds. Using random forest classification and regression, we modelled the presence–absence of mussels as a group (87% accuracy), the abundances of 29 individual mussel species (R2 = 0.2–0.51), species richness (R2 = 0.52) and total mussel abundance in a standard sample (R2 = 0.41). The abundances of most species increased with stream size, the proportion of agricultural land in the catchment and the distance to the nearest dam or pond, but decreased with increasing catchment or channel slope and the proportion of forest in the catchment. Species varied in their relationships with climate variables, suggesting that they respond differently to climate change. Geology, particularly bedrock depth, was important for many species. Species richness and total mussel abundance responded positively to stream size and negatively to the slope of streams or catchments. The models were applied to unsampled wadeable stream reaches to generate mussel distribution maps at the reach scale, useful tools for resource managers to effectively protect and restore mussel biodiversity. The models also improve our understanding of how mussel populations and assemblages are structured by natural factors and human disturbances at a broad scale.

Conspecific Aggression by Beavers (Castor canadensis) in the Sangamon River Basin in Central Illinois: Correlates with Habitat, Age, Sex and Season

Abstract Conspecific aggression may play an important role in partitioning resources and maintaining territories among beavers (Castor canadensis), yet few studies have examined physical evidence of agonistic encounters. We trapped and examined pelts from 147 beavers harvested between 2006 and 2012 from the Sangamon River (n = 96) and tributary streams (n = 51) in central Illinois. We modeled the influence of sex, age class, season (predispersal or dispersal), and habitat (river or tributary stream) on the number of recent injuries caused by conspecifics. One-third (51/147) of beavers had ≥1 injury; of those, the median number of injuries was 2.0. Kits had fewer injuries than adults (βKit = −2.24 ± 0.63), but yearlings and subadults did not (βyearling = 0.02 ± 0.38, βsubadult = −0.22 ± 0.48). Beavers on small streams had only one-quarter of the injuries recorded for beavers on the river (βStream = −1.34 ± 0.82). We failed to detect differences in injuries between the sexes. Our results suggest...

A review of the Nearctic genus Prostoia (Ricker) (Plecoptera, Nemouridae), with the description of a new species and a surprising range extension for P. hallasi Kondratieff & Kirchner.

The Nearctic genus Prostoia (Plecoptera: Nemouridae) is reviewed. Prostoia ozarkensis sp. n. is described from the male and female adult stages mainly from the Interior Highland region encompassing portions of Arkansas, Missouri, and Oklahoma. Prostoia ozarkensis sp. n. appears most closely related to two species, one distributed broadly across the western Nearctic region, P. besametsa (Ricker), and one found widely throughout the central and eastern Nearctic regions, P. completa (Walker). A surprising range extension is noted for P. hallasi Kondratieff & Kirchner, a species once known only from the Great Dismal Swamp, from small upland streams in southern Illinois. Additional new state records are documented for P. besametsa, P. completa, P. hallasi and P. similis (Hagen). Taxonomic keys to Prostoia males and females are provided, and scanning electron micrographs of adult genitalia of all species are given.

Scavenger or predator? Examining a potential predator–prey relationship between crayfish and benthic fish in stream food webs

AbstractCommonly referred to as keystone species, crayfish are ecologically important for their ability to transfer energy efficiently to higher trophic levels in aquatic food webs. They also are ecosystem engineers, modifying substrate and influencing distribution of other benthic invertebrates. However, crayfish have yet to be examined as potential predators of benthic fish in lotic systems. We examined a possible relationship between crayfish and benthic fish populations by quantifying natural densities of both groups and by using enclosure/exclosure and laboratory experiments to test for crayfish predation on benthic fish. Data obtained by sampling Illinois streams showed that increased crayfish density was correlated with decreased fish density, and this relationship was not influenced by habitat variables. Data from in-stream enclosure/exclosure experiments showed predation by crayfish (Orconectes sp.) on darters (Etheostoma sp.) in all treatments. The highest overall fish mortality occurred in the ...

Using Maxent to model the historic distributions of stonefly species in Illinois streams: The effects of regularization and threshold selections

Species distribution model (SDMs) is increasingly used to determine the distribution range of individual species and identify biodiversity hotspots. Of many technical issues, model over-fitting or over-parameterization is a major concern, which can lead to severe under-prediction. However, under-fitting and over-prediction may also occur if species requirements for environment are inadequately modeled. We used the collection data of stoneflies (Plecoptera, Insecta) from Illinois, USA to examine how often and severely maximum entropy (Maxent) over- or under-predicts species richness and species-occurrence frequency. A recently proposed AICc-based method (Warren and Seifert, 2011) was used for model-complexity control or regularization. Twenty-nine historically well-sampled watersheds were used to validate the predictions. The standard models, which used the default regularization (β=1), over- or under-predicted, depending on the watershed, species, and threshold used for converting suitability score into species presence–absence. The AICc-selected models (β=7–40) used 77% less parameters, but often strongly and consistently over-predicted. Three thresholds, equal training sensitivity and specificity, maximizing training sensitivity and specificity (MTSS) and minimum training presence, yielded most accurate estimates. Accordingly, we developed standard models for 41 species and identified the historically species-rich watersheds in Illinois. Our results offer new insight into the effects of regularization and choices of thresholds on Maxent performances.

Mercury in small Illinois fishes: historical perspectives and current issues

Documenting long-term trends in mercury deposition and/or accumulation is important in setting regulatory benchmarks, modeling contaminant transfer and flux, measuring success of environmental controls, and even assigning responsibility for pollution. We conducted a study to compare mercury concentrations in small fishes from "high-mercury" and "low-mercury" regions of Illinois, as well as to examine historic patterns of mercury availability using preserved fishes. Mercury concentrations were greater in four species of small fishes collected from a stream in a "high-mercury" region than in those same taxa collected from a stream in a "low-mercury" area in Illinois. Mercury concentrations in blackstripe topminnows (Fundulus notatus) declined dramatically between 1900 and 1961/2006 in the "high-mercury" stream, presumably due reductions in mercury releases from local and regional sources. Preserved fish had an apparent increase in mercury concentrations for up to 12months, which is consistent with changes in mass and loss of proteins observed in other studies, and we recommend that recent samples be preserved for at least 12months before comparison with older fluid-preserved material. Based on our results, further studies of mercury in small fishes in Illinois streams appear warranted.

Assessing sampling adequacy of mussel diversity surveys in wadeable Illinois streams

Freshwater mussels are one of the most imperiled groups of animals in North America. Effective resource management and conservation efforts require reliable estimates of species diversity and their distributions. However, sampling protocols for qualitative mussel surveys have not been well established and tested. Furthermore, the sampling effort required for a given data-quality goal (90% of species captured) often varies substantially among sites, and application of a standard effort probably would introduce bias into assemblage comparisons. We tested the sampling adequacy of time-based hand searches. We conducted 16-man-hour (mh) searches at each of 18 wadeable stream sites in Illinois that differed widely in environmental factors and historical species diversity and collected 27 to 942 individuals and 5 to 18 species per site. We accounted for imperfect species detectability by using the Chao-1 richness estimator and measured sampling adequacy as the % of the estimated number of species sampled. Four-mh searches, a frequently used effort, captured 15 to 100% of all species with an average of 61%, and yielded estimates of richness that were not significantly correlated with the estimated total richness (Pearson’s r = 0.39, p > 0.05). Ten-mh searches captured >70% of all species at >70% of sites and resulted in a significant correlation between observed and estimated richness (Pearson’s r ≥ 0.78, p < 0.01). A Random Forests (RF) model based on watershed and habitat characteristics (e.g., stream size and dominant substrate types) accounted for 45% of the variance in sampling adequacy of 4-mh searches. Sampling adequacy decreased with increasing stream size and substrate size but increased with % forest in the riparian zone and logs in the stream. A 2nd RF model was developed to predict the number of man-hours required to capture 70 ± 3% of all species, and it accounted for 37% of the variance. Our findings should serve as a guide for setting standard sampling efforts for mussel surveys in Illinois and probably other midwestern states and should provide a baseline for setting site-specific efforts. Our modeling approach is of general applicability for addressing sampling-adequacy issues in studies of any assemblage.

Secondary production in a southern Illinois headwater stream: relationships between organic matter standing stocks and macroinvertebrate productivity

We quantified macroinvertebrate production and organic matter standing stocks in riffle/run and pool habitats for 2 y in 2 reaches of Big Creek, a 3rd-order stream in southern Illinois, USA. Habitat-weighted secondary production was 24.9 and 26.2 g ash-free dry mass (AFDM) m−2 y−1 in the upper and lower reaches, respectively, in year 1 of the study and 17.6 and 15.1 AFDM m−2 y−1 in year 2. Annual production to biomass (P/B) ratios of the macroinvertebrate assemblages ranged from 7 to 10. Collector-gatherers, which were dominated by nontanypodine Chironomidae and Oligochaeta, accounted for >60% of total habitat-weighted production in both reaches, and consumption estimates based on production efficiencies indicated they consumed high proportions of available organic matter resources ≤250 µm. Macroinvertebrate production in Big Creek was strongly correlated with organic matter standing stocks, and our subsequent analyses of production and organic matter resources across several low-order North American streams suggested standing stocks of small wood, a relatively refractory component of organic matter, are an important component of the relationship between macroinvertebrate production and organic matter. However, the apparent influence of small wood on production may be related to associated physical characteristics of these streams, such as pH and canopy cover. Secondary production estimates in our data set were a function of both adjusted total organic matter exclusive of wood and wood standing stocks. Although production–organic matter relationships may be obscured by other factors at the local level, our results indicate that patterns of macroinvertebrate production across large geographic scales may be driven largely by the availability of detrital resources.

Whole Catchment Land Cover Effects on Water Quality in the Lower Kaskaskia River Watershed

Agricultural runoff is a major non-point source pollutant and is the leading impairment of streams and rivers in the USA. This study examined the effects of agricultural, forest and urban land cover on water quality at the watershed level. Forty-three catchments ranging from 12 to 50 km2 were selected based on a land cover gradient within Lower Kaskaskia River Watershed in Illinois. Grab samples were collected and analyzed for nutrients, bacteria, and total suspended solids (TSS). Forest land cover was included in six of the ten regression models produced. Four of these regression models were for base flow conditions, suggesting that forest land cover had a significant impact on base flow water quality. Urban land cover was also included in six of the regression models. However, the majority were during storm flow conditions implying urban land cover had a greater impact on storm flow conditions. Watersheds were further categorized into agriculture, village, and urban watersheds. During base flow conditions agriculture watersheds had significantly higher TSS concentrations and urban watersheds had significantly higher ortho-P concentrations. In all watersheds, ortho-P concentrations were above the statewide 95th percentile for Illinois streams. Escherichia coli levels during storm conditions exceeded the national US EPA criteria.