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At least 163 records · Page 9Linked to original sources
USGS2022

Trout responses to stocking rates and river discharge within a southeast U.S. hydropeaking tailwater

Freshwater fish populations often exist in systems characterized by novel ecological processes resulting from human alteration. Salmonid populations embedded within coldwater sections of warmwater rivers are spatially constrained by habitat availability. Tailwater fish contend with fluctuating river discharges and density-dependent processes associated with fish stocking and exploitation. Salmonid populations sustained through stocking versus natural reproduction may respond differently to changes in hydrologic patterns (e.g., hydropeaking) as well as declines in fish abundance. We assessed differences between stocked (Rainbow Trout Oncorhynchus mykiss ) and naturalized (Brown Trout Salmo trutta ) trout populations in Greers Ferry tailwater, Arkansas, regarding (1) spatial and temporal patterns of mean length, electrofishing catch rates, and relative condition following reduced number of stocked Rainbow Trout and (2) evidence that hydrologic characteristics and fish stocking intensity influenced relative condition. A 56% reduction in Rainbow Trout stocking did not result in systemwide change in mean length or relative abundance for Rainbow Trout or Brown Trout over the 16-year study period. Hydrologic variability, where river discharge spanned both reduced and elevated levels, positively influenced condition of both Rainbow Trout and Brown Trout. Assessment of survival of stocked Rainbow Trout may aid in further refining the timing and amount of stocking needed to sustain the population at a desired abundance. Further, assessing the influence of stocking fewer but perhaps larger (in terms of mean length) fish to meet management goals may be warranted. The persistent differences in relative abundance among river sections can inform management actions directed at Brown Trout, including harvest regulations. Such regulations may aid in reaching desired management goals, including abundance and mean length targets not observed after reduced stocking.

Arkansas↗
USGS2013

Newly documented host fishes for the eastern elliptio mussel (Elliptio complanata)

The eastern elliptio Elliptio complanata is a common, abundant, and ecologically important freshwater mussel that occurs throughout the Atlantic Slope drainage in the United States and Canada. Previous research has shown E. complanata glochidia to be host fish generalists, parasitizing yellow perch Perca flavescens , banded killifish Fundulus diaphanus , banded sculpin Cottus carolinae , and seven centrarchid species. Past laboratory studies have been conducted in the Midwest; however, glochidia used in these studies were obtained from adult mussels in the Great Lakes or St. Lawrence River basins, or glochidia sources were not reported. The objective of this study was to identify host fishes for E. complanata from streams in the Mid-Atlantic region. We used artificial laboratory infections to test host suitability of 38 fish and 2 amphibian species with E. complanata glochidia from the Chesapeake Bay drainage. Glochidia successfully metamorphosed into juvenile mussels on five fish species: American eel Anguilla rostrata , brook trout Salvelinus fontinalis , lake trout Salvelinus namaycush , mottled sculpin Cottus bairdii , and slimy sculpin Cottus cognatus . American eel was the most effective host, yielding the highest overall metamorphosis success (percentage of attached glochidia that transformed into juvenile mussels; ≥0.90) and producing 13.2 juveniles per fish overall. No juvenile E. complanata metamorphosed on other fish or amphibian species tested, including many previously identified host fishes that appear in the literature. Reasons for discrepancies in published host fish could include geographic variation in host use across the species' range, differences in host use between lentic and lotic populations, or poorly resolved taxonomy within the genus Elliptio .

Journal of Fish and Wildlife Management↗
USGS2005

Fish can get diseases too

Infectious diseases are increasingly recognized as an important component of the ecology of fish in the wild. Many of the viral, bacterial, protozoan and fungal pathogens of fish that were initially discovered in captive fish have their origin among wild populations; however, the impact of disease among these free-ranging stocks has been difficult to study. At the WFRC, combinations of field and laboratory investigations, aided by the tools of molecular biology, have begun to provide information on the ecology of infectious diseases among natural populations of fish in both freshwater and marine ecosystems.

Fact Sheet↗
USGS2011

Defining conservation priorities for freshwater fishes according to taxonomic, functional, and phylogenetic diversity

To date, the predominant use of systematic conservation planning has been to evaluate and conserve areas of high terrestrial biodiversity. Although studies in freshwater ecosystems have received recent attention, research has rarely considered the potential trade-offs between protecting different dimensions of biodiversity and the ecological processes that maintain diversity. We provide the first systematic prioritization for freshwaters (focusing on the highly threatened and globally distinct fish fauna of the Lower Colorado River Basin, USA) simultaneously considering scenarios of: taxonomic, functional, and phylogenetic diversity; contemporary threats to biodiversity (including interactions with nonnative species); and future climate change and human population growth. There was 75% congruence between areas of highest conservation priority for different aspects of biodiversity, suggesting that conservation efforts can concurrently achieve strong complementarity among all types of diversity. However, sizable fractions of the landscape were incongruent across conservation priorities for different diversity scenarios, underscoring the importance of considering multiple dimensions of biodiversity and highlighting catchments that contribute disproportionately to taxonomic, functional, and phylogenetic diversity in the region. Regions of projected human population growth were not concordant with conservation priorities; however, higher human population abundance will likely have indirect effects on native biodiversity by increasing demand for water. This will come in direct conflict with projected reductions in precipitation and warmer temperatures, which have substantial overlap with regions of high contemporary diversity. Native and endemic fishes in arid ecosystems are critically endangered by both current and future threats, but our results highlight the use of systematic conservation planning for the optimal allocation of limited resources that incorporates multiple and complementary conservation values describing taxonomic, functional, and phylogenetic diversity.

Ecological Applications↗
USGS2026

Putting weight to work: A review and examples of weight-based indicators in freshwater fish stock assessment

Despite being a direct measure of biomass and central to fisheries management, weight-based metrics remain underutilized in freshwater fish stock assessment. Here, we present a concise review of the application of weight in evaluating freshwater fish populations. We examine the historical use of weighing, assess how weight is applied across subdisciplines of freshwater fish science, contrast weight- and length-based approaches, and identify biases in their application. We then synthesize weight-based metrics, indices, and models within four broad categories—population and community weight structure; condition, growth, and efficiency; reproductive potential and production; and yield and exploitation dynamics—highlighting approaches that inform fish ecology, population and community dynamics, and vital rates. We conclude by identifying key opportunities and methodological innovations needed to expand the effective use of weight-based metrics in freshwater fish conservation and management.

North American Journal of Fisheries Management↗
USGS2014

Acoustic telemetry reveals large-scale migration patterns of walleye in Lake Huron

Fish migration in large freshwater lacustrine systems such as the Laurentian Great Lakes is not well understood. The walleye ( Sander vitreus ) is an economically and ecologically important native fish species throughout the Great Lakes. In Lake Huron walleye has recently undergone a population expansion as a result of recovery of the primary stock, stemming from changing food web dynamics. During 2011 and 2012, we used acoustic telemetry to document the timing and spatial scale of walleye migration in Lake Huron and Saginaw Bay. Spawning walleye ( n = 199) collected from a tributary of Saginaw Bay were implanted with acoustic tags and their migrations were documented using acoustic receivers ( n = 140) deployed throughout U.S. nearshore waters of Lake Huron. Three migration pathways were described using multistate mark-recapture models. Models were evaluated using the Akaike Information Criterion. Fish sex did not influence migratory behavior but did affect migration rate and walleye were detected on all acoustic receiver lines. Most (95%) tagged fish migrated downstream from the riverine tagging and release location to Saginaw Bay, and 37% of these fish emigrated from Saginaw Bay into Lake Huron. Remarkably, 8% of walleye that emigrated from Saginaw Bay were detected at the acoustic receiver line located farthest from the release location more than 350 km away. Most (64%) walleye returned to the Saginaw River in 2012, presumably for spawning. Our findings reveal that fish from this stock use virtually the entirety of U.S. nearshore waters of Lake Huron.

Michigan, Ontario↗
USGS2023

Glacial vicariance and secondary contact shape demographic histories in a freshwater mussel species complex

Characterizing the mechanisms influencing the distribution of genetic variation in aquatic species can be difficult due to the dynamic nature of hydrological landscapes. In North America’s Central Highlands, a complex history of glacial dynamics, long-term isolation, and secondary contact have shaped genetic variation in aquatic species. Although the effects of glacial history have been demonstrated in many taxa, responses are often lineage- or species-specific and driven by organismal ecology. In this study, we reconstruct the evolutionary history of a freshwater mussel species complex using a suite of mitochondrial and nuclear loci to resolve taxonomic and demographic uncertainties. Our findings do not support Pleurobema rubrum as a valid species, which is proposed for listing as threatened under the U.S. Endangered Species Act. We synonymize P. rubrum under Pleurobema sintoxia —a common and widespread species found throughout the Mississippi River Basin. Further investigation of patterns of genetic variation in P. sintoxia identified a complex demographic history, including ancestral vicariance and secondary contact, within the Eastern Highlands. We hypothesize these patterns were shaped by ancestral vicariance driven by the formation of Lake Green and subsequent secondary contact after the last glacial maximum. Our inference aligns with demographic histories observed in other aquatic taxa in the region and mirrors patterns of genetic variation of a freshwater fish species ( Erimystax dissimilis ) confirmed to serve as a parasitic larval host for P. sintoxia . Our findings directly link species ecology to observed patterns of genetic variation and may have significant implications for future conservation and recovery actions of freshwater mussels.

Mississippi River basin↗
USGS2011

Ictalurids in Iowa’s streams and rivers: Status, distribution, and relationships with biotic integrity

Anthropogenic alterations to Iowa’s landscape have greatly altered lotic systems with consequent effects on the biodiversity of freshwater fauna. Ictalurids are a diverse group of fishes and play an important ecological role in aquatic ecosystems. However, little is known about their distribution and status in lotic systems throughout Iowa. The purpose of this study was to describe the distribution of ictalurids in Iowa and examine their relationship with ecological integrity of streams and rivers. Historical data (i.e., 1884–2002) compiled for the Iowa Aquatic Gap Analysis Project (IAGAP) were used to detect declines in the distribution of ictalurids in Iowa streams and rivers at stream segment and watershed scales. Eight variables characterizing ictalurid assemblages were used to evaluate relationships with index of biotic integrity (IBI) ratings. Comparisons of recent and historic data from the IAGAP database indicated that 9 of Iowa’s 10 ictalurid species experienced distribution declines at one or more spatial scales. Analysis of variance indicated that ictalurid assemblages differed among samples with different IBI ratings. Specifically, total ictalurid, sensitive ictalurid, and Noturus spp. richness increased as IBI ratings increased. Results indicate declining ictalurid species distributions and biotic integrity are related, and management strategies aimed to improve habitat and increase biotic integrity will benefit ictalurid species.

American Fisheries Society Symposium↗
USGS1981

The freshwater‐inflow‐to‐estuaries issue

Over 55% of the United States commercial fish and shellfish catch is dependent upon estuaries for spawning and nursery functions, but estuaries cannot function ecologically without an adequate supply, seasonal inflow, and quality of freshwater from inland rivers. Such inland river development projects as constructing reservoirs, leveeing rivers, dredging navigation channels, and diverting water for agriculture, cities, and industry have drastically changed freshwater inflows to many estuaries on the Atlantic and Pacific coasts and the Gulf of Mexico. The problems on the Atlantic coast are primarily reduced water quality and increased rate of runoff although reductions in quantity appear to be developing. On the Gulf of Mexico decreases in freshwater inflow quantity have reduced estuarine production on the Florida and Texas coasts. On the highly productive Mississippi Delta, levee and navigation channel construction has diverted river inflow to the Gulf of Mexico rather than allowing overflow to the estuarine habitats; this has resulted in saltwater intrusion and marsh erosion. On the Pacific coast, inflow to the San Francisco Bay complex has been reduced by over 50%, resulting in drastic estuarine changes. Studies on freshwater inflow are underway in Chesapeake Bay, Louisiana, Texas, and the San Francisco Bay complex. The freshwater‐inflow‐to‐estuary problem can be addressed by (1) considering the ecological effects of proposed inland water projects on estuarine production and communities; (2) developing nationwide criteria for evaluating the freshwater needs of estuaries; (3) refining methods for defining the economic and noneconomic benefit of freshwater inflow to estuaries; and (4) using existing laws and directives more effectively.

Fisheries↗
USGS1995

Southeastern freshwater fishes

North America has the richest fauna of temperate freshwater fishes in the world, with about 800 native species in the waters of Canada and the United States. The center of this diversity is in the southeastern United States, where as many as 500 species may exist (62% of the continental fauna north of Mexico). Many coastal marine species also enter fresh waters of the Southeast, and at least 34 foreign fish species are established in the region. Although freshwater fishes of the United States are better studied than any fish fauna of comparable scope in the world (Lee et al. 1980; Hocutt and Wiley 1986; Matthews and Heins 1987; Page and Burr 1991; Mayden 1992), large gaps exist in scientific knowledge about the biology and ecology of most species. New species are still being discovered, and the taxonomy of other species is being refined. Seriously declining populations of freshwater fishes in the United States concern the scientific community (Deacon et al. 1979; Williams et al. 1989; Moyle and Leidy 1992; Warren and Burr 1994). This article briefly summarizes the current conservation status of southeastern freshwater fishes; the Southeast is emphasized because of its important fish biodiversity and to focus attention on the growing problem of adverse human impacts on the region's aquatic habitats (Mount 1986; Burkhead and Jenkins 1991; Etnier and Starnes 1991; Warren and Burr 1994).

Book chapter↗
USGS2026

Two hundred years of historical spawning and nursery data for coregonine fishes in the Laurentian Great Lakes

Historical data can provide critical ecological information for species across the globe, many of which are facing unprecedented rates of ecosystem change. Yet, historical information related to freshwater species, especially fishes, remains scattered, often in original formats, and underutilized for informing conservation and restoration activities. Here, we present a Data Descriptor called Coregonine Spawning History (CORHIST), a database designed to house diverse data related to past spawning and nursery areas for fishes in the family Salmonidae, subfamily Coregoninae (ciscoes and whitefishes), in the Laurentian Great Lakes and their tributaries. Data for 11 species of coregonines historically occurring in the Great Lakes are included in CORHIST. Over 3,400 occurrence records at the coordinate scale have been entered, over 2,200 of which are for Cisco ( Coregonus artedi ) and Lake Whitefish ( C. clupeaformis )—two focal species for which there is either multinational conservation interest or restoration efforts underway in the Laurentian Great Lakes. CORHIST is already proving useful for several studies developing habitat suitability models and delineating spatial units for conservation or restoration planning.

Laurentian Great Lakes↗
USGS2014

A multi-indicator framework for mapping cultural ecosystem services: The case of freshwater recreational fishing

Despite recent interest, ecosystem services are not yet fully incorporated into private and public decisions about natural resource management. Cultural ecosystem services (CES) are among the most challenging of services to include because they comprise complex ecological and social properties and processes that make them difficult to measure, map or monetize. Like others, CES are vulnerable to landscape changes and unsustainable use. To date, the sustainability of services has not been adequately addressed and few studies have considered measures of service capacity and demand simultaneously. To facilitate sustainability assessments and management of CES, our study objectives were to (1) develop a spatially explicit framework for mapping the capacity of ecosystems to provide freshwater recreational fishing, an important cultural service, (2) map societal demand for freshwater recreational fishing based on license data and identify areas of potential overuse, and (3) demonstrate how maps of relative capacity and relative demand could be interfaced to estimate sustainability of a CES. We mapped freshwater recreational fishing capacity at the 12-digit hydrologic unit-scale in North Carolina and Virginia using a multi-indicator service framework incorporating biophysical and social landscape metrics and mapped demand based on fishing license data. Mapping of capacity revealed a gradual decrease in capacity eastward from the mountains to the coastal plain and that fishing demand was greatest in urban areas. When comparing standardized relative measures of capacity and demand for freshwater recreational fishing, we found that ranks of capacity exceeded ranks of demand in most hydrologic units, except in 17% of North Carolina and 5% of Virginia. Our GIS-based approach to view freshwater recreational fishing through an ecosystem service lens will enable scientists and managers to examine (1) biophysical and social factors that foster or diminish cultural ecosystem services delivery, (2) demand for cultural ecosystem services relative to their capacity, and (3) ecological pressures like potential overuse that affect service sustainability. Ultimately, we expect such analyses to inform decision-making for freshwater recreational fisheries and other cultural ecosystem services.

Ecological Indicators↗
USGS2024

Length in assessing status of freshwater fish populations: A review

Objective Effective policy formulation regarding the conservation of freshwater fish necessitates an understanding of water‐specific prevailing conditions and trends. Assessing fish populations in inland waters is difficult and expensive because there are many independent systems that need to be evaluated. Therefore, numerous freshwater systems are beset by insufficient data and the lack of systematic assessments of their status. To alleviate this deficiency, the objective of this study was to review length‐based metrics that may have utility in evaluating the well‐being of freshwater fish populations. Methods Length measurements can serve as proxies for a range of ecological and population dynamics attributes that are essential for the effective management of fish and associated fisheries. A review of the historical development of length measurements in fish conservation is provided, along with an examination of the potential biases that may arise from the use of lengths in practical contexts. In addition, we examine techniques that enable the spatial and temporal visualization of length data sets, as well as a range of indices and metrics that can be computed using length measurements. Result Building populations assessments around length may be a cost‐effective strategy that allows a first cut at managing a large number of waters. Length‐based assessments can signal if management intervention is necessary, if management policies are yielding the intended outcome, or if surveys beyond mere length are necessary. Conclusion Our review indicates that length offers a straightforward and efficient approach to evaluate the status of fish populations in inland systems. We encourage pursuing additional study and to this end propose specific areas for investigation.

North American Journal of Fisheries Management↗
USGS2003

Aquatic invertebrate assemblages in shallow prairie lakes: Fish and environmental influences

We sampled zooplankton and benthic macroinvertebrate assemblages in 30 shallow natural lakes to determine the effects of the environment (i.e., habitat and fish abundance) on invertebrates. Zooplankters were identified to genus, and up to 120 individuals per genus were measured. Macroinvertebrates were identified to order, class, or family. Fish communities were also sampled. Relative abundances of zooplankton and macroinvertebrates were low at increased chlorophyll a concentrations, although mean zooplankton length increased with total phosphorus, possibly because of an increased proportion of microzooplankton (rotifers and copepod nauplii) at higher phosphorus levels. Canonical correspondence analysis revealed that zooplankton and macroinvertebrate abundance was influenced by submersed vegetation coverage, whereas zooplankton abundance and size structure were also related to productivity (i.e., chlorophyll a and total phosphorus). However, relative abundance of fish species or fish feeding guilds was not strongly correlated with zooplankton or macroinvertebrate abundance or zooplankton size structure. Physical habitat (e.g., vegetation coverage) may exert substantial influences on invertebrate assemblages in these lakes , possibly providing a refuge from fish predation.

Journal of Freshwater Ecology↗
USGS2023

Evaluation of threatened, endangered, and rare fish species and communities of the St. Lawrence River and its tributaries in the United States

Biodiversity is responsible for important ecological processes like productivity and ecosystem stability, and rare species are a major component of biodiversity. Rarity increases a species' vulnerability to disturbances and also makes them difficult to study. Globally, species of freshwater systems are some of the most threatened, and evaluation of rare freshwater species and their habitats is needed to help preserve natural flexibility and ecological function. We conducted an analysis of full fish communities of the upper St. Lawrence River and its major US tributaries, with the goals of determining species locations and abundances, associated environmental conditions, the distribution of distinct fish assemblages across the landscape (with emphasis on communities supporting rare species), and potential threats. From 2009 to 2015, the US Geological Survey (USGS) and Saint Regis Mohawk Tribe (SRMT) worked together using standardized methods to collect community samples within 4 different aquatic realms (shallow and deep lentic, and small and large lotic systems) and determine species-specific fish abundances, frequencies of occurrence, and associated habitat signatures and spatial distributions. Distinct fish assemblages and associated habitat conditions were objectively identified by multivariate and hypothesis-testing methods. We used a geographic information system (GIS) to spatially associate habitat, biotic, and landscape attributes within each stream reach throughout the study area, facilitating quantification of distribution patterns. Comparisons with historical data provided estimates of loss or gain of threatened and endangered species (T&E) colonies. We developed a disturbance index to highlight potential threats to aquatic species. More than 140,000 fishes of 87 species were collected from a total of 1140 sample sites, covering 278 stream reaches, including the endangered Notropis anogenus (Pugnose Shiner), and threatened Hiodon tergisus (Mooneye), Etheostoma pellucidum (Eastern Sand Darter), and Acipenser fulvescens (Lake Sturgeon). We identified 50 distinct fish assemblages differing in species composition, abundance, and/or diversity, but only 13 of those assemblages included a T&E species. The rareness, extent, and patchiness of fish assemblages created a mosaic of fish communities across the landscape, from headwaters to the mainstem of the St. Lawrence River. Comparisons with historic surveys (1978–2008) showed a stable number of T&E species colonies or an increase for some species. The geographic distribution of multimetric disturbance index values showed where combinations of disturbances to fish habitats might affect rare fish species and aquatic communities in the region. The species–habitat associations and fish assemblage distributions can be used for evaluation of species, communities, or habitats that may need protection or restoration.

St. Lawrence River study area↗
USGS2026

Effects of 6PPD, 6PPD-quinone, and potential alternatives on freshwater mussels.

N-(1,3-dimethylbutyl)-N'-phenyl-p-phenylenediamine (6PPD) is an antioxidant and antiozonant widely used in tires. When 6PPD reacts with ozone, it transforms into a breakdown product called 6PPD-quinone (6PPDQ). Both compounds are currently being studied because of their high aquatic toxicity to fish, particularly coho salmon ( Oncorhynchus kisutch ). The Washington State Legislature directed Ecology to perform an Alternatives Assessment on 6PPD in motor vehicle tires. The goal is to identify and evaluate potential replacement compounds for these products. As part of this work, Ecology is studying how potential alternatives interact with species of concern and compare those effects with what is already known about 6PPD and 6PPDQ. One of those species of concern is freshwater mussels. Freshwater mussels are an imperiled group of organisms with high cultural and ecological significance. However, there are major data gaps concerning how 6PPD affects aquatic species other than salmonids. Mussels are of particular concern due to their unique parasitic life cycle where a fish host is required to fully develop into a juvenile. If their fish host is sensitive to 6PPD, mussel populations could also be at risk. This project aims to determine lethal and sublethal toxicity of 6PPD, 6PPDQ, and any potential alternatives to freshwater mussels. This objective will be accomplished by conducting acute toxicity tests with the compounds to determine median lethal concentrations (LC 50 s) of the tested compounds to freshwater mussels. Sublethal toxicity will be studied by then determining if the presence of 6PPD, 6PPDQ, and potential alternatives impacts the mussel’s ability to use a fish host for the important parasitic stage of its life cycle.

Washington↗
USGS2009

Research in thermal biology: Burning questions for coldwater stream fishes

With the increasing appreciation of global warming impacts on ecological systems, in addition to the myriad of land management effects on water quality, the number of literature citations dealing with the effects of water temperature on freshwater fish has escalated in the past decade. Given the many biological scales at which water temperature effects have been studied, and the growing need to integrate knowledge from multiple disciplines of thermal biology to fully protect beneficial uses, we held that a survey of the most promising recent developments and an expression of some of the remaining unanswered questions with significant management implications would best be approached collectively by a diverse research community. We have identified five specific topic areas of renewed research where new techniques and critical thought could benefit coldwater stream fishes (particularly salmonids): molecular, organism, population/species, community and ecosystem, and policy issues in water quality. Our hope is that information gained through examination of recent research fronts linking knowledge at various scales will prove useful in managing water quality at a basin level to protect fish populations and whole ecosystems. Standards of the past were based largely on incipient lethal and optimum growth rate temperatures for fish species, while future standards should consider all integrated thermal impacts to the organism and ecosystem. ?? Taylor and Francis Group, LLC.

Reviews in Fisheries Science↗
USGS2011

How restructuring river connectivity changes freshwater fish biodiversity and biogeography

Interbasin water transfer projects, in which river connectivity is restructured via man-made canals, are an increasingly popular solution to address the spatial mismatch between supply and demand of fresh water. However, the ecological consequences of such restructuring remain largely unexplored, and there are no general theoretical guidelines from which to derive these expectations. River systems provide excellent opportunities to explore how network connectivity shapes habitat occupancy, community dynamics, and biogeographic patterns. We apply a neutral model (which assumes competitive equivalence among species within a stochastic framework) to an empirically derived river network to explore how proposed changes in network connectivity may impact patterns of freshwater fish biodiversity. Without predicting the responses of individual extant species, we find the addition of canals connecting hydrologically isolated river basins facilitates the spread of common species and increases average local species richness without changing the total species richness of the system. These impacts are sensitive to the parameters controlling the spatial scale of fish dispersal, with increased dispersal affording more opportunities for biotic restructuring at the community and landscape scales. Connections between isolated basins have a much larger effect on local species richness than those connecting reaches within a river basin, even when those within-basin reaches are far apart. As a result, interbasin canal projects have the potential for long-term impacts to continental-scale riverine communities.

Water Resources Research↗