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Geology topics

Shannon K. Brewer

Publications and source records attributed to Shannon K. Brewer.

At least 73 records · Page 4Linked to original sources

Subterranean invasion by gapped ringed crayfish: Effectiveness of a removal effort and barrier installation

Non-native crayfish invasion is a major threat to many stream fauna; however, invasions in subterranean habitats are rarely documented. Our study objectives were to examine demographics and morphological and life-history traits of a gapped ringed crayfish Faxonius neglectus chaenodactylus population that invaded Tumbling Creek Cave and determine the effects of removal on the population. Crayfish were found throughout the cave though fewer individuals were observed upstream of an installed weir. Fecund females were collected in nearly all months, but were prevalent during spring (February–June). Males and females were of similar sizes. Males had larger chelae and chelae that were regenerated slightly more often than females. Removal of >4000 crayfish since 2011 resulted in reduced abundances, but the population persisted. Age estimates from counting bands on gastric mills indicated crayfish within the cave lived longer than populations in nearby Big Creek (6 vs. 4 years). Recent efforts to prevent upstream cave migrations included a barrier installation and since installation, few crayfish have been located upstream. We show that exploitation of new environments may lead to trait changes (i.e., reproduction and longevity). We also demonstrate that barriers reduce the spread of invasion at a comparable cost to removal. We hypothesize that increased reservoir elevation inundates springs hydrologically connected to the cave and this may be the invasion source.

Missouri↗

Movement and diel habitat use of juvenile Neosho Smallmouth Bass in an Ozark stream

Documenting fish movement patterns and examining relationships with both fish and habitat characteristics are essential aspects of sound conservation and management. Stream fish movement and habitat use have been associated with a myriad of factors, and variability among individuals is common. Movement and habitat use patterns of juvenile Smallmouth Bass Micropterus dolomieu in streams are poorly understood, particularly for the Neosho subspecies M. dolomieu velox . Our study objective was to determine diel movement patterns and microhabitat use by juvenile Neosho Smallmouth Bass during late autumn. In 2016, we surgically implanted radio transmitters into 13 juvenile Smallmouth Bass in Honey Creek, Oklahoma. We tracked the fish by using radiotelemetry on 41 occasions over the 26‐d tag life and located fish throughout the diel cycle to characterize movement and habitat use. Movement patterns varied among individual fish, with cumulative movements ranging from 33 to 1,302 m. Incremental displacement (the distance moved between two consecutive relocations) increased slightly with warmer water temperatures and increasing fish size. Although there was also considerable individual variation in habitat use patterns, deeper habitats were associated with larger juvenile Smallmouth Bass and daytime. Fish also tended to use higher‐velocity habitats during the day, and this trend increased over the duration of the study. Our results suggest high individual variation in both movement and habitat use by juvenile Neosho Smallmouth Bass across the diel cycle. We show that juvenile Smallmouth Bass move among microhabitats and would benefit from management actions that maintain and promote instream habitat complexity. Future efforts focused on juvenile Smallmouth Bass movement over longer time periods would be beneficial for understanding movement and habitat use dynamics across a greater range of seasonal and environmental variability.

Oklahoma↗

Relationships between landscape constraints and a crayfish assemblage with consideration of competitor presence

Aim Crayfish are globally diverse and one of the most important taxa in North American streams. Despite their importance, many species are of conservation concern and efforts to improve conditions are limited. Here, we address two major impediments to improving conditions: (a) our lack of knowledge of the interplay among natural landscape and human-induced changes; and (b) a very limited understanding of how species interactions affect overall crayfish distributions. Location Ozark Highlands ecoregion, USA. Methods We used both existing data and field-collected data to examine the relationships between 12 Faxonius species and physicochemical variables at multiple spatial scales. Data were analysed using a generalized linear mixed model. After fitting our environmental variables, we also considered possible relationships between species considered strong competitors and species occurrence. Results Our results indicated that elevation, lithology, an interaction between drainage area and anthropogenic disturbance, and the presence of strong competitors were associated with Faxonius occurrences. Faxonius occurrences were associated with assemblage-structuring variables: lithology and elevation. More interestingly, we found several patterns of interactions between drainage area and disturbance. The most common pattern among several species was a decline in occurrence in larger drainages when disturbance was high; however, longpincered crayfish ( Faxonius longidigitus ) was more likely to occupy large drainages as disturbance increased. Additionally, the presence of species considered strong competitors resulted in lower occurrence probability for many species, including two of the species classified as competitors. Main conclusions In addition to identifying the relationships between native species and assemblage-structuring variables, we show how the probability of species occurrences relate to interactions between disturbance and natural landscape features. Further, our results suggest competitor presence also plays a role in structuring distributions at the stream segment scale. Our findings emphasize the value of considering both competitor presence and interactions among landscape variables and disturbances in structuring crayfish assemblages.

Arkansas, Missouri↗

Geomorphic identification of physical habitat features in a large, altered river system

Altered flow regimes in streams can significantly affect ecosystems and disturb ecological processes, leading to species loss and extinction. Many river management projects use stream classification and habitat assessment approaches to design practical solutions to reverse or mitigate adverse effects of flow regime alteration on stream systems. The objective of this study was to develop a methodology to provide a primary identification of physical habitats in an 80-km long segment of the Canadian River in central Oklahoma. The methodology relied on basic geomorphic Geomorphic identification of physical habitat features in a large, altered river system erial imagery and Lidar data using Geographic Information Systems. Geostatistical tests were implemented to delineate habitat units. This approach based on high resolution data and did not require in-site inspection provided a relatively refined habitat delineation, consistent with visual observations. Future efforts will focus on validation via field surveys and coupling with hydro-sedimentary modeling to provide a tool for environmental flow decisions.

Oklahoma↗

Hybridization and genetic structure of Neosho Smallmouth Bass in the Ozark Highlands

The Neosho Smallmouth Bass Micropterus dolomieu velox is endemic to Arkansas River tributaries originating in the Ozark Highlands and Boston Mountains. Although morphologically and genetically distinct from other populations of Smallmouth Bass M. dolomieu , the conservation‐genetic status of Neosho Smallmouth Bass is largely unknown. To assist in filling this data gap, we quantified introgressive hybridization, genetic diversity, and population structure of Neosho Smallmouth Bass in two major river basins (Grand River and Illinois River) using seven polymorphic microsatellite markers. Introgressive hybridization with stocked Tennessee lake‐strain Smallmouth Bass was most prevalent in the Illinois River, wherein the overall genomic proportion of Neosho Smallmouth Bass alleles was only 0.422. After accounting for hybrid individuals, genetic diversity of Neosho Smallmouth Bass was generally higher in larger rivers and lower in smaller, isolated streams. Three distinct population clusters were identified at the uppermost level of genetic structure—one from the Illinois River basin and two from the Grand River basin. These three population boundaries accounted for approximately 7% of the hierarchical genetic variation within our data set, and substructure below the uppermost level accounted for an additional 2% of genetic variation. The population structure we discovered can provide a blueprint for management that conserves diversity within and among populations; for example, population boundaries can be used to determine brood source locations for supplemental stocking efforts to counter nonnative introgression. Introgressive hybridization with nonnative Smallmouth Bass appears to be the most pertinent threat to the Neosho Smallmouth Bass subspecies, which is of conservation value to the overall adaptability of Smallmouth Bass as a species.

Missouri, Oklahoma↗

Efficiency of sampling sunfishes using snorkeling in clear, warmwater streams of the south-central United States

The continued evaluation of fish-sampling gears and methods is essential to identify their applicability across environmental conditions and among species. Although limited by visibility, snorkeling has potential advantages relative to other fish-sampling gears in wadeable streams (e.g., minimally intrusive, cost effective, and appropriate in deeper areas). Clear water is common to warm-water streams; however, the use of snorkeling for monitoring stream-fish populations has largely focused on cold-water systems. To assess relative snorkeling efficiency in warm-water streams, we compared standardized single-pass snorkel counts to tow-barge electrofishing abundance estimates for six sunfishes (Centrarchidae) in the Ozark Highlands ecoregion of northwest Oklahoma and southwest Missouri under relatively similar environmental conditions (i.e., clear water, cobble substrates, low-flow conditions). Snorkeling efficiency was variable among sunfishes and consistently low for species with cryptic traits and habitat use. We also did not detect cryptic sunfishes (i.e., a single individual was not encountered) using snorkeling at multiple stream reaches where estimated abundance was > 50 within a 0.5- to 1.0-km stream reach. Our findings indicate that snorkeling has applications for monitoring sunfish populations and assemblages when using an abundance estimator or accounting for imperfect detection; however, it is inappropriate for estimating population size of cryptic sunfishes. We encourage continued research into the applicability of snorkeling to estimate warm-water stream fish abundance.

Missouri, Oklahoma↗

Habitat associations of three crayfish endemic to the Ouachita Mountain Ecoregion

Many crayfish are of conservation concern because of their use of unique habitats and often narrow ranges. In this study, we determined fine-scale habitat use by 3 crayfishes that are endemic to the Ouachita Mountains, in Oklahoma and Arkansas. We sampled Faxonius menae (Mena Crayfish), F. leptogonopodus (Little River Creek Crayfish), and Fallicambarus tenuis (Ouachita Mountain Crayfish) from wet and dry erosional channel units of 29 reaches within the Little River catchment. We compared channel-unit and microhabitat selection for each species. Crayfish of all species and life stages selected erosional channel units more often than depositional units, even though these sites were often dry. Accordingly, crayfish at all life stages typically selected the shallowest available microhabitats. Adult crayfish of all species and juvenile Little River Creek Crayfish selected patches of coarse substrate, and all crayfish tended to use the lowest amount of bedrock available. In general, we showed that these endemic crayfish used erosional channel units of streams, even when the channel units were dry. Conservation efforts that protect erosional channel units and mitigate actions that cause channel downcutting to bedrock would benefit these crayfish, particularly during harsh, summer drying periods.

Oklahoma↗

Synthesizing models useful for ecohydrology and ecohydraulic approaches: An emphasis on integrating models to address complex research questions

Ecohydrology combines empiricism, data analytics, and the integration of models to characterize linkages between ecological and hydrological processes. A challenge for practitioners is determining which models best generalizes heterogeneity in hydrological behaviour, including water fluxes across spatial and temporal scales, integrating environmental and socio‐economic activities to determine best watershed management practices and data requirements. We conducted a literature review and synthesis of hydrologic, hydraulic, water quality, and ecological models designed for solving interdisciplinary questions. We reviewed 1,275 papers and identified 178 models that have the capacity to answer an array of research questions about ecohydrology or ecohydraulics. Of these models, 43 were commonly applied due to their versatility, accessibility, user‐friendliness, and excellent user‐support. Forty‐one of 43 reviewed models were linked to at least 1 other model especially: Water Quality Analysis Simulation Program (linked to 21 other models), Soil and Water Assessment Tool (19), and Hydrologic Engineering Center's River Analysis System (15). However, model integration was still relatively infrequent. There was substantial variation in model applications, possibly an artefact of the regional focus of research questions, simplicity of use, quality of user‐support efforts, or a limited understanding of model applicability. Simply increasing the interoperability of model platforms, transformation of models to user‐friendly forms, increasing user‐support, defining the reliability and risk associated with model results, and increasing awareness of model applicability may promote increased use of models across subdisciplines. Nonetheless, the current availability of models allows an array of interdisciplinary questions to be addressed, and model choice relates to several factors including research objective, model complexity, ability to link to other models, and interface choice.

Ecohydrology↗

Quantifying seining detection probability for fishes of Great Plains sand‐bed rivers

Species detection error (i.e., imperfect and variable detection probability) is an essential consideration when investigators map distributions and interpret habitat associations. When fish detection error that is due to highly variable instream environments needs to be addressed, sand‐bed streams of the Great Plains represent a unique challenge. We quantified seining detection probability for diminutive Great Plains fishes across a range of sampling conditions in two sand‐bed rivers in Oklahoma. Imperfect detection resulted in underestimates of species occurrence using naïve estimates, particularly for less common fishes. Seining detection probability also varied among fishes and across sampling conditions. We observed a quadratic relationship between water depth and detection probability, in which the exact nature of the relationship was species‐specific and dependent on water clarity. Similarly, the direction of the relationship between water clarity and detection probability was species‐specific and dependent on differences in water depth. The relationship between water temperature and detection probability was also species dependent, where both the magnitude and direction of the relationship varied among fishes. We showed how ignoring detection error confounded an underlying relationship between species occurrence and water depth. Despite imperfect and heterogeneous detection, our results support that determining species absence can be accomplished with two to six spatially replicated seine hauls per 200‐m reach under average sampling conditions; however, required effort would be higher under certain conditions. Detection probability was low for the Arkansas River Shiner Notropis girardi , which is federally listed as threatened, and more than 10 seine hauls per 200‐m reach would be required to assess presence across sampling conditions. Our model allows scientists to estimate sampling effort to confidently assess species occurrence, which maximizes the use of available resources. Increased implementation of approaches that consider detection error promote ecological advancements and conservation and management decisions that are better informed.

Oklahoma↗

Groundwater flux estimation in streams: A thermal equilibrium approach

Stream and groundwater interactions play an essential role in regulating flow, temperature, and water quality for stream ecosystems. Temperature gradients have been used to quantify vertical water movement in the streambed since the 1960s, but advancements in thermal methods are still possible. Seepage runs are a method commonly used to quantify exchange rates through a series of streamflow measurements but can be labor and time intensive. The objective of this study was to develop and evaluate a thermal equilibrium method as a technique for quantifying groundwater flux using monitored stream water temperature at a single point and readily available hydrological and atmospheric data. Our primary assumption was that stream water temperature at the monitored point was at thermal equilibrium with the combination of all heat transfer processes, including mixing with groundwater. By expanding the monitored stream point into a hypothetical, horizontal one-dimensional thermal modeling domain, we were able to simulate the thermal equilibrium achieved with known atmospheric variables at the point and quantify unknown groundwater flux by calibrating the model to the resulting temperature signature. Stream water temperatures were monitored at single points at nine streams in the Ozark Highland ecoregion and five reaches of the Kiamichi River to estimate groundwater fluxes using the thermal equilibrium method. When validated by comparison with seepage runs performed at the same time and reach, estimates from the two methods agreed with each other with an R 2 of 0.94, a root mean squared error (RMSE) of 0.08 (m/d) and a Nash–Sutcliffe efficiency (NSE) of 0.93. In conclusion, the thermal equilibrium method was a suitable technique for quantifying groundwater flux with minimal cost and simple field installation given that suitable atmospheric and hydrological data were readily available.

Oklahoma↗

Sampling the stream landscape: Improving the applicability of an ecoregion-level capture probability model for stream fishes

Temporal and spatial variability in streams result in heterogeneous gear capture probability (i.e., the proportion of available individuals identified) that confounds interpretation of data used to monitor fish abundance. We modeled tow-barge electrofishing capture probability at multiple spatial scales for nine Ozark Highland stream fishes. In addition to fish size, we identified seven reach-scale environmental characteristics associated with variable capture probability: stream discharge, water depth, conductivity, water clarity, emergent vegetation, wetted width–depth ratio, and proportion of riffle habitat. The magnitude of the relationship between capture probability and both discharge and depth varied among stream fishes. We also identified lithological characteristics among stream segments as a coarse-scale source of variable capture probability. The resulting capture probability model can be used to adjust catch data and derive reach-scale absolute abundance estimates across a wide range of sampling conditions with similar effort as used in more traditional fisheries surveys (i.e., catch per unit effort). Adjusting catch data based on variable capture probability improves the comparability of data sets, thus promoting both well-informed conservation and management decisions and advances in stream-fish ecology.

Arkansas, Missouri, Oklahoma↗

Incorporating an approach to aid river and reservoir fisheries in an altered landscape

Reservoir construction for human-use services alters connected riverine flow patterns and influences fish production. We sampled two pelagic fishes from two rivers and two reservoirs and related seasonal and annual hydrology patterns to the recruitment and growth of each species. River and reservoir populations of Freshwater Drum Aplodinotus grunniens reached similar ages (32 and 31, respectively). Likewise, longevity of Gizzard Shad Dorosoma cepedianum between the two systems was also similar (7 and 8 years, respectively). However, both species grew larger in the rivers compared to reservoir residents. Recruitment of Freshwater Drum in reservoirs was negatively related to water retention time (r2=0.59) suggesting moving water through the reservoir was beneficial. Riverine recruitment of Freshwater Drum populations was negatively related to the annual number of flow reversals and positively related to prespawn discharge (r2 = 0.33). Unlike Freshwater Drum, there was no relationship between flow metrics and Gizzard Shad recruitment in reservoirs. However, recruitment of riverine Gizzard Shad was positively related to high flow pulses during the prespawn and spawning seasons (r2 = 0.48). The growth of both species in reservoirs was positively related to the number of days each year that water levels were above the conservation pool. Growth of Freshwater Drum was also negatively related to minimum reservoir summer water levels (r2 = 0.84). Growth of both Freshwater Drum and Gizzard Shad occupying lotic systems was positively related to May (r2 = 0.86) and July discharge (r2 = 0.84), respectively. In general, growth and recruitment of the reservoir populations was more related to annual water patterns, whereas riverine fishes responded more to seasonal flow patterns. Results of this study provide important information on the relationship between hydrology and pelagic fish production in both rivers and reservoirs. This information is useful if agencies are interested in developing holistic river-reservoir water-allocation plans.

Cooperator Science Series↗

Passive integrated transponder tags: Review of studies on warmwater fishes with notes on additional species

Although numerous studies have assessed retention and survival of passive integrated transponder (PIT) tags, data are scattered and information gaps remain for many diminutive fishes. Our study objectives were to 1) systematically review PIT tag studies and summarize retention, growth, and survival data for warmwater fishes; and 2) conduct a laboratory study to evaluate the retention, survival, and growth effects of intracoelomic-placed, half duplex PIT tags on six small-bodied species common to warmwater streams. Our systematic review suggested small sample sizes were common within PIT tag retention and survival studies (39% with n ≤ 20) and that many experiments (15%, 14 of 97) failed to use control fish as part of their evaluations. Studies focused primarily on short-term changes (15 d to 2 y) in tag retention and survival. Tag retention was equal to or greater than 90% in 85% of the experiments reviewed and median survival was 92%. Growth was reported by fishes in the majority of reviewed studies. We found similar results after PIT tagging (peritoneum tagging using 12- or 23-mm half duplex tags) adult Cardinal Shiner Luxilus cardinalis , Central Stoneroller Campostoma annomalum , Greenside Darter Etheostoma blennioides , Orangethroat Darter Etheostoma spectabile , Slender Madtom Noturus exilis , and juvenile Smallmouth Bass Micropterus dolomieu . Tag retention for all species was high, with only one tag loss recorded after 60 d. Survival was also high (≥88%) for all of our species with the exception of Orangethroat Darter (56% survival). No significant difference in mean growth between treatment and control groups was found. Both our results and the findings of the literature review suggested generally high tag retention and low mortality in tagged fishes (across 31 species reviewed). However, within our study (e.g., Orangethroat Darter) and from the literature, examples of negative effects of PIT tagging on fishes were apparent, suggesting methodological testing is prudent before using PIT tags in field studies. We suggest future studies would benefit from addressing the behavioral implications that may be associated with tagging and examination of longer-term tag retention. Furthermore, standard reporting (i.e., sample sizes) in PIT tag studies would be beneficial, and use of control subjects or groups for statistical comparisons is needed.

Journal of Fish and Wildlife Management↗

Multinomial N-mixture models improve the applicability of electrofishing for developing population estimates of stream-dwelling Smallmouth Bass

Failure to account for variable detection across survey conditions constrains progressive stream ecology and can lead to erroneous stream fish management and conservation decisions. In addition to variable detection’s confounding long-term stream fish population trends, reliable abundance estimates across a wide range of survey conditions are fundamental to establishing species–environment relationships. Despite major advancements in accounting for variable detection when surveying animal populations, these approaches remain largely ignored by stream fish scientists, and CPUE remains the most common metric used by researchers and managers. One notable advancement for addressing the challenges of variable detection is the multinomial N -mixture model. Multinomial N -mixture models use a flexible hierarchical framework to model the detection process across sites as a function of covariates; they also accommodate common fisheries survey methods, such as removal and capture–recapture. Effective monitoring of stream-dwelling Smallmouth Bass Micropterus dolomieu populations has long been challenging; therefore, our objective was to examine the use of multinomial N -mixture models to improve the applicability of electrofishing for estimating absolute abundance. We sampled Smallmouth Bass populations by using tow-barge electrofishing across a range of environmental conditions in streams of the Ozark Highlands ecoregion. Using an information-theoretic approach, we identified effort, water clarity, wetted channel width, and water depth as covariates that were related to variable Smallmouth Bass electrofishing detection. Smallmouth Bass abundance estimates derived from our top model consistently agreed with baseline estimates obtained via snorkel surveys. Additionally, confidence intervals from the multinomial N -mixture models were consistently more precise than those of unbiased Petersen capture–recapture estimates due to the dependency among data sets in the hierarchical framework. We demonstrate the application of this contemporary population estimation method to address a longstanding stream fish management issue. We also detail the advantages and trade-offs of hierarchical population estimation methods relative to CPUE and estimation methods that model each site separately.

Missouri, Oklahoma↗

Effects of temperature, total dissolved solids, and total suspended solids on survival and development rate of larval Arkansas River Shiner

Decreases in the abundance and diversity of stream fishes in the North American Great Plains have been attributed to habitat fragmentation, altered hydrological and temperature regimes, and elevated levels of total dissolved solids and total suspended solids. Pelagic-broadcast spawning cyprinids, such as the Arkansas River Shiner Notropis girardi , may be particularly vulnerable to these changing conditions because of their reproductive strategy. Our objectives were to assess the effects of temperature, total dissolved solids, and total suspended solids on the developmental and survival rates of Arkansas River Shiner larvae. Results suggest temperature had the greatest influence on the developmental rate of Arkansas River Shiner larvae. However, embryos exposed to the higher levels of total dissolved solids and total suspended solids reached developmental stages earlier than counterparts at equivalent temperatures. Although this rapid development may be beneficial in fragmented waters, our data suggest it may be associated with lower survival rates. Furthermore, those embryos incubating at high temperatures, or in high levels of total dissolved solids and total suspended solids resulted in less viable embryos and larvae than those incubating in all other temperature, total dissolved solid, and total suspended solid treatment groups. As the Great Plains ecoregion continues to change, these results may assist in understanding reasons for past extirpations and future extirpation threats as well as predict stream reaches capable of sustaining Arkansas River Shiners and other species with similar early life-history strategies.

Journal of Fish and Wildlife Management↗

Thermal tolerances of fishes occupying groundwater and surface-water dominated streams

A thermal tolerance study mimicking different stream environments could improve our ecological understanding of how increasing water temperatures affect stream ectotherms and improve our ability to predict organism responses based on river classification schemes. Our objective was to compare the thermal tolerances of stream fishes of different habitat guilds among 3 exposure periods: critical thermal maximum (CTmax, increase of 2°C/h until loss of equilibrium [LOE] and death [D]), and 2 longer-term treatments (net daily increase of 1°C) that mimicked spring-fed (SF; 4°C daily increase) and non-spring-fed (NSF; 8°C daily increase) conditions. Fishes in the pelagic habitat guild had a 1°C higher average CTmax than benthic fishes. Thermal responses of species depended on exposure period with higher and increased variation in tolerances associated with the SF and NSF exposure periods. Logperch, Orangebelly Darter, Orangethroat Darter, and Southern Redbelly Dace were more sensitive to thermal increases regardless of SF or NSF treatment than were the 3 remaining species (Brook Silverside, Central Stoneroller, and Redspot Chub), which represented average thermal responses among the species tested. The 3 species that had a higher thermal response to CTmax-D (lethal endpoint of death) also were able to increase their tolerances more than other species in both SF and NSF treatments. Our data indicate finer guild designations may be useful for predicting thermal-response patterns. A diel thermal refuge increases the thermal responses of ectotherms to daily maxima, but the patterns across our SF and NSF treatments were similar suggesting minimum refuge temperatures may be more important than maximums. Nonetheless, stream temperature cooling over a 24-h period is important to ectotherm thermal tolerances, a result suggesting that sources of cooler water to streams might benefit from protection.

Freshwater Science↗

Organizing environmental flow frameworks to meet hydropower mitigation needs

The global recognition of the importance of natural flow regimes to sustain the ecological integrity of river systems has led to increased societal pressure on the hydropower industry to change plant operations to improve downstream aquatic ecosystems. However, a complete reinstatement of natural flow regimes is often unrealistic when balancing water needs for ecosystems, energy production, and other human uses. Thus, stakeholders must identify a prioritized subset of flow prescriptions that meet ecological objectives in light of realistic constraints. Yet, isolating aspects of flow regimes to restore downstream of hydropower facilities is among the greatest challenges of environmental flow science due, in part, to the sheer volume of available environmental flow tools in conjunction with complex negotiation-based regulatory procedures. Herein, we propose an organizational framework that structures information and existing flow paradigms into a staged process that assists stakeholders in implementing environmental flows for hydropower facilities. The framework identifies areas where regulations fall short of the needed scientific process, and provide suggestions for stakeholders to ameliorate those situations through advanced preparation. We highlight the strengths of existing flow paradigms in their application to hydropower settings and suggest when and where tools are most applicable. Our suggested framework increases the effectiveness and efficiency of the e-flow implementation process by rapidly establishing a knowledge base and decreasing uncertainty so more time can be devoted to filling knowledge gaps. Lastly, the framework provides the structure for a coordinated research agenda to further the science of environmental flows related to hydropower environments.

Environmental Management↗