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Daren M Carlisle, Ph.D.

Dr. Daren Carlisle manages the Ecological Flows Program for the Water Resources Mission Area.

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The Chaudiere Dam diverts water from the Ottawa River, Canada

Streamflow Alteration

Humans, just like aquatic organisms, need water. Flood control, urban infrastructure, irrigation of agriculture, and myriad other ways we manage water affect the natural flow of streams and rivers. How do the ways we manage land and water affect the natural patterns of streamflow that ecosystems depend on?
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Water Resources Mission Area, National Water Quality Program
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Streamflow Alteration

Humans, just like aquatic organisms, need water. Flood control, urban infrastructure, irrigation of agriculture, and myriad other ways we manage water affect the natural flow of streams and rivers. How do the ways we manage land and water affect the natural patterns of streamflow that ecosystems depend on?
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Sampling during ecological surveys as part of the Regional Stream Quality Assessment

Stream Ecology

Who lives in your stream? Rivers and streams, even small ones, are teeming with a vast number of species, including fish, aquatic invertebrates, and algae. Stream ecology is the study of those aquatic species, the way they interrelate, and their interactions with all aspects of these flowing water systems.
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Water Resources Mission Area, National Water Quality Program
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Stream Ecology

Who lives in your stream? Rivers and streams, even small ones, are teeming with a vast number of species, including fish, aquatic invertebrates, and algae. Stream ecology is the study of those aquatic species, the way they interrelate, and their interactions with all aspects of these flowing water systems.
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New Croton Dam is part of New York City's water supply system

Effects of flow alteration on ecological health of streams across the Atlantic Highlands Ecoregion

Problem: The Clean Water Act (PL 92-500) requires that the health of the Nation’s rivers and streams be assessed on a regular basis, and in the Northeast such assessments often use information from aquatic biological communities that live in the stream. Biomonitoring programs implemented by individual states evaluate biological data to assess stream health on the premise that certain sensitive s
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New York Water Science Center
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Effects of flow alteration on ecological health of streams across the Atlantic Highlands Ecoregion

Problem: The Clean Water Act (PL 92-500) requires that the health of the Nation’s rivers and streams be assessed on a regular basis, and in the Northeast such assessments often use information from aquatic biological communities that live in the stream. Biomonitoring programs implemented by individual states evaluate biological data to assess stream health on the premise that certain sensitive s
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Predicted Streamflow Modification in Contiguous United States Streams

Empirical models described in previous publications were developed and applied to estimate the probability of streamflow modification for every stream segment in the conterminous United States from 1980-2015. This metadata record documents 6 comma separated tables populated with predictions of streamflow modification (please see the Supplemental Element for citations or please refer to the cross-r
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Water Resources Mission Area

Regional-scale Model Predictions of the Relation Between Biological Integrity and Streamflow Modification

The US Geological Survey (USGS) conducted a study (Carlisle and others 2017) with a national-scale dataset composed of ecological data from the USGS National Water-Quality Assessment Project and the US Environmental Protection Agency, matched to USGS streamgaging sites. In a follow-up study (Carlisle and others 2019), additional data from three regional assessments conducted by USGS were combined
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Water Resources Mission Area

Data Release for: A Web-Based Tool for Assessing the Condition of Benthic Diatom Assemblages in Streams and Rivers of the Conterminous United States

Benthic diatom assemblages are known to be indicative of water quality but have yet to be widely adopted in biological assessments in the United States due to several limitations. Our goal was to address some of these limitations by developing regional multi-metric indices (MMIs) that are robust to inter-laboratory taxonomic inconsistency, adjusted for natural covariates, and sensitive to a wide r
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Water Resources Mission Area

Functional Flow Metrics for Select Reference Sites in California: Data Release for Modeling

The hydrologic modeling approach used to predict functional flows relies on daily streamflow data from gages operated by the U.S. Geological Survey (USGS) in California. This dataset contains, for each of 219 gages, a collection of metrics computed on each water year for the period of record to and including Water Year 2016.
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Water Resources Mission Area

Monthly estimates of natural baseflow for 15,866 stream reaches, defined by the National Hydrography Dataset Plus Version 2.0 (NHDPlusV2), in the Delaware River Basin for the period 1950-2015

This metadata record describes monthly estimates of natural baseflow for 15,866 stream reaches, defined by the National Hydrography Dataset Plus Version 2.0 (NHDPlusV2), in the Delaware River Basin for the period 1950-2015. A statistical machine learning technique - random forest modeling (Liaw and Wiener, 2018; R Core Team, 2020) - was applied to estimate natural flows using about 150 potential p
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Water Resources Mission Area

Datasets for estimating invertebrate response to changes in total nitrogen, total phosphorus, and specific conductance at sites where invertebrate data are unavailable

These data were used to describe a possible approach to estimate changes in invertebrate taxa richness at sites across the United States with known water-quality trends but no invertebrate data. This data release consists of invertebrate, water-quality, and covariate data from 1,322 sites and water-quality, covariate, and trend result data from an additional 259 sites with reported water-quality t
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Colorado Water Science Center

Data set for an ecological risk assessment of Firpronil compounds in US streams

The phenylpyrazole insecticide fipronil and its degradates are a potential surface-water contaminant and toxicant to nontarget species such as aquatic macroinvertebrates. To better understand how fipronil, fipronil sulfide, fipronil sulfone, desulfinyl fipronil, and fipronil amide affect aquatic communities, a 30-day mesocosm experiment was run. Rock trays were colonized with natural benthic commu
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Colorado Water Science Center

Trends in selected streamflow metrics at reference streamgages in the conterminous United States, 1980-2014

This dataset includes four tables related to annual trends in streamflow metrics at 599 reference streamgages in the conterminous United States for the period 1955-2014. Reference streamgages are defined here as gages with drainage basins that are minimally impacted by anthropogenic effects such as reservoirs or urbanization. The four tables are: 1) computed annual values for 16 streamflow metrics
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Water Resources Mission Area

Datasets used to asses the effects of antecedent streamflow and sample timing on trend assessments of fish, invertebrate and diatom communities (2002-12)

Detecting trends in biological attributes is central to many stream monitoring programs; however, understanding how natural variability in environmental factors affects trend results is not well understood. We evaluated the influence of antecedent streamflow and sample timing (covariates) on trend estimates for fish, invertebrate, and diatom taxa richness and biolgical condition from 2002 to 2012
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Water Resources Mission Area

Linking the Agricultural Landscape of the Midwest to Stream Health with Structural Equation Modeling: Model Input Data

Biological, chemical, physical habitat, riparian, and land-use data collected from the Midwest streams by the National Water Quality Project Regional Stream Quality Team. Data were used to develop structural equation models for the purpose of understanding how networks of potential stressors influence stream ecological health. For more information about the Midwest Regional Stream Quality Assessme
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Water Resources Mission Area, National Water Quality Program

Natural Monthly Flow Estimates for the Conterminous United States, 1950-2015

This metadata record describes monthly estimates of natural stream flows for greater than 2.5 million stream reaches, defined by the National Hydrography Dataset (NHD) Version 2.0, in the conterminous United States for the period 1950-2015. A statistical machine learning technique - random forest modeling - was applied to estimate natural flows using 200 potential predictor variables. The dataset
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Water Resources Mission Area, National Water Quality Program

Matched ecological assessment and stream gaging data for the CONUS

Ecological assessment data from the USGS National Water-Quality Assessment Program and the USEPA National River and Stream Assessment were reviewed and records were retained from sampling sites co-located with active USGS stream gages. A limited amount of ancillary data, including location, physical watershed features, and basic water chemistry data for each site were also retained.
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Water Resources Mission Area, National Water Quality Program
Filter Total Items: 52

Biological assessments of aquatic ecosystems

The aim of biological assessments (or bioassessments) is to provide decision makers and managers the scientific information and tools needed to protect and restore aquatic life. Biological assessments typically include several critical elements, including development of ecological indicators, indices of ecological status, benchmarks by which to gauge impairment, ways to identify the stressors caus
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Water Resources Mission Area

Ecological consequences of neonicotinoid mixtures in streams

Neonicotinoid mixtures are common in streams worldwide, but corresponding ecological responses are poorly understood. We combined experimental and observational studies to narrow this knowledge gap. The mesocosm experiment determined that concentrations of the neonicotinoids imidacloprid and clothianidin (range of exposures, 0 to 11.9 μg/liter) above the hazard concentration for 5% of species (0.0
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Ecosystems Mission Area, Water Resources Mission Area, Contaminant Biology, Environmental Health Program, Toxic Substances Hydrology, Wyoming-Montana Water Science Center

Modeling functional flows in California rivers

Environmental flows are critical to the recovery and conservation of freshwater ecosystems worldwide. However, estimating desired ranges of environmental flows across large, diverse landscapes is challenging. To advance protections of environmental flows for streams in California, USA, we developed a statewide modeling approach focused on functional components of the natural flow regime. Functiona
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Water Resources Mission Area

Toward improved prediction of streamflow effects on freshwater fishes

Understanding the effects of hydrology on fish populations is essential to managing for native fish conservation. However, despite decades of research illustrating streamflow influences on fish habitat, reproduction and survival, biologists remain challenged when tasked with predicting how fish populations will respond to changes in flow regimes. This uncertainty stems from insufficient understand
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Cooperative Research Units

A web-based tool for assessing the condition of benthic diatom assemblages in streams and rivers of the conterminous United States

Benthic diatom assemblages are known to be indicative of water quality but have yet to be widely adopted in biological assessments in the United States due to several limitations. Our goal was to address some of these limitations by developing regional multi-metric indices (MMIs) that are robust to inter-laboratory taxonomic inconsistency, adjusted for natural covariates, and sensitive to a wide r
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Water Resources Mission Area

Estimating invertebrate response to changes in total nitrogen, total phosphorus, and specific conductance at sites where invertebrate data are unavailable

The purpose of this report is to describe a possible approach to estimate changes in invertebrate taxa richness at sites with known water-quality trends but no invertebrate data. In this study, data from 1,322 sites were used to describe invertebrate response to changes in total nitrogen, total phosphorus, or specific conductance, and to estimate changes in invertebrate taxa richness at 259 sites
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Water Resources Mission Area, Colorado Water Science Center

Multiple in-stream stressors degrade biological assemblages in five U.S. regions

Biological assemblages in streams are affected by a wide variety of physical and chemical stressors associated with land-use development, yet the importance of combinations of different types of stressors is not well known. From 2013 to 2017, the U.S. Geological Survey completed multi-stressor/multi-assemblage stream ecological assessments in five regions of the United States (434 streams total).
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Ecosystems Mission Area, Water Resources Mission Area, Contaminant Biology, Environmental Health Program, Toxic Substances Hydrology, California Water Science Center, Kansas Water Science Center, Oklahoma-Texas Water Science Center, Oregon Water Science Center, South Atlantic Water Science Center (SAWSC), Washington Water Science Center, Wyoming-Montana Water Science Center

Linking altered flow regimes to biological condition: An example using benthic macroinvertebrates in small streams of the Chesapeake Bay watershed

Regionally scaled assessments of hydrologic alteration for small streams and its effects on freshwater taxa are often inhibited by a low number of stream gages. To overcome this limitation, we paired modeled estimates of hydrologic alteration to a benthic macroinvertebrate index of biotic integrity data for 4522 stream reaches across the Chesapeake Bay watershed. Using separate random-forest model
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Chesapeake Bay Activities

Multi-region assessment of chemical mixture exposures and predicted cumulative effects in USA wadeable urban/agriculture-gradient streams

Chemical-contaminant mixtures are widely reported in large stream reaches in urban/agriculture-developed watersheds, but mixture compositions and aggregate biological effects are less well understood in corresponding smaller headwaters, which comprise most of stream length, riparian connectivity, and spatial biodiversity. During 2014–2017, the U.S. Geological Survey (USGS) measured 389 unique orga

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Ecosystems Mission Area, Water Resources Mission Area, Contaminant Biology, Environmental Health Program, Toxic Substances Hydrology, California Water Science Center, Colorado Water Science Center, Maryland-Delaware-D.C. Water Science Center, New Jersey Water Science Center, Ohio-Kentucky-Indiana Water Science Center, Oklahoma-Texas Water Science Center, Oregon Water Science Center, South Atlantic Water Science Center (SAWSC)

Ecological forecasting—21st century science for 21st century management

Natural resource managers are coping with rapid changes in both environmental conditions and ecosystems. Enabled by recent advances in data collection and assimilation, short-term ecological forecasting may be a powerful tool to help resource managers anticipate impending near-term changes in ecosystem conditions or dynamics. Managers may use the information in forecasts to minimize the adverse ef

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Ecosystems Mission Area, Water Resources Mission Area, Wildlife Program (unpublished), Contaminant Biology, Environmental Health Program, Science Analytics and Synthesis (SAS) Program, Eastern Ecological Science Center, Fort Collins Science Center, Kansas Water Science Center, Maryland-Delaware-D.C. Water Science Center, National Wildlife Health Center, New Jersey Water Science Center, Pacific Island Ecosystems Research Center, Patuxent Wildlife Research Center, Southwest Biological Science Center, Upper Midwest Environmental Sciences Center, Upper Midwest Water Science Center

Biofilms provide new insight into pesticide occurrence in streams and links to aquatic ecological communities

Streambed sediment is commonly analyzed to assess occurrence of hydrophobic pesticides and risks to aquatic communities. However, stream biofilms also have the potential to accumulate pesticides and may be consumed by aquatic organisms. To better characterize risks to aquatic life, the U.S. Geological Survey Regional Stream Quality Assessment measured 93 current-use and 3 legacy pesticides in bed
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Water Resources Mission Area

Diatom enumeration method influences biological assessments of southeastern USA streams

Current fixed-count enumeration methods for benthic diatoms are likely inadequate for most research and monitoring objectives. These methods underestimate taxa richness and may fail to detect losses of species caused by human impacts. Consequently, the full potential of diatoms is not realized in current assessments of biological integrity or species diversity. In this study, we hypothesize that a
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Water Resources Mission Area
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Modification of Streamflow Across the U.S.

Human activities have caused flows in many of the Nation’s streams and rivers to be different from what they would be naturally. A new USGS study repo...

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